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Sample records for advanced flame quality

  1. The advanced flame quality indicator system

    Energy Technology Data Exchange (ETDEWEB)

    Oman, R.; Rossi, M.J.; Calia, V.S.; Davis, F.L.; Rudin, A. [Insight Technologies, Inc., Bohemia, NY (United States)

    1997-09-01

    By combining oil tank monitoring, systems diagnostics and flame quality monitoring in an affordable system that communicates directly with dealers by telephone modem, Insight Technologies offers new revenue opportunities and the capability for a new order of customer relations to oil dealers. With co-sponsorship from New York State Energy Research and Development Authority, we have incorporated several valuable functions to a new product based on the original Flame Quality Indicator concept licensed from the US DOE`s Brookhaven National Laboratory. The new system is the Advanced Flame Quality Indicator, or AFQI. As before, the AFQI monitors and reports the intensity of the burner flame relative to a calibration established when the burner is set up at AFQI installation. Repairs or adjustments are summoned by late-night outgoing telephone calls when limits are exceeded in either direction, indicating an impending contamination or other malfunction. A independently, a pressure transducer for monitoring oil tank level and filter condition, safety lockout alarms and a temperature monitor; all reporting automatically at instructed intervals via an on-board modem to a central station PC computer (CSC). Firmware on each AFQI unit and Insight-supplied software on the CSC automatically interact to maintain a customer database for an oil dealer, an OEM, or a regional service contractor. In addition to ensuring continuously clean and efficient operation, the AFQI offers the oil industry a new set of immediate payoffs, among which are reduced outages and emergency service calls, shorter service calls from cleaner operation, larger oil delivery drops, the opportunity to stretch service intervals to as along as three years in some cases, new selling features to keep and attract customers, and greatly enhanced customer contact, quality and reliability.

  2. Recent Advances in Flame Tomographyt

    Institute of Scientific and Technical Information of China (English)

    闫勇; 邱天; 卢钢; M.M.Hossain; G.Gilabert; 刘石

    2012-01-01

    To reduce greenhouse gas emissions from fossil fuel fired power plants,a range of new combustion technologies are being developed or refined,including oxy-fuel combustion,co-firing biomass with coal and fluidized bed combustion.Flame characteristics under such combustion conditions are expected to be different from those in normal air fired combustion processes.Quantified flame characteristics such as temperature distribution,oscillation frequency,and ignition volume play an important part in the optimized design and operation of the environmentally friendly power generation systems.However,it is challenging to obtain such flame characteristics particularly through a three-dimensional and non-intrusive means.Various tomography methods have been proposed to visualize and characterize flames,including passive optical tomography,laser based tomography,and electrical tomography.This paper identifies the challenges in flame tomography and reviews existing techniques for the quantitative characterization of flames.Future trends in flame tomography for industrial applications are discussed.

  3. Removing baseline flame's spectrum by using advanced recovering spectrum techniques.

    Science.gov (United States)

    Arias, Luis; Sbarbaro, Daniel; Torres, Sergio

    2012-09-01

    In this paper, a novel automated algorithm to estimate and remove the continuous baseline from measured flame spectra is proposed. The algorithm estimates the continuous background based on previous information obtained from a learning database of continuous flame spectra. Then, the discontinuous flame emission is calculated by subtracting the estimated continuous baseline from the measured spectrum. The key issue subtending the learning database is that the continuous flame emissions are predominant in the sooty regions, in absence of discontinuous radiation. The proposed algorithm was tested using natural gas and bio-oil flames spectra at different combustion conditions, and the goodness-of-fit coefficient (GFC) quality metric was used to quantify the performance in the estimation process. Additionally, the commonly used first derivative method (FDM) for baseline removing was applied to the same testing spectra in order to compare and to evaluate the proposed technique. The achieved results show that the proposed method is a very attractive tool for designing advanced combustion monitoring strategies of discontinuous emissions. PMID:22945158

  4. Advanced monitoring of industrial burners based on fluctuating flame signals

    Energy Technology Data Exchange (ETDEWEB)

    A. Sanz; J. Ballester; R. Hernandez; L.M. Cerecedo [University of Zaragoza, Zaragoza (Spain). Fluid Mechanics Group/LITEC

    2008-06-15

    The present work explores the potential of pressure and radiation sensors for the advanced monitoring/control of industrial flames. These instruments are rugged, non-intrusive and non-expensive and might be used in routine plant operation to obtain direct information from the flame. However, further research is needed to assess the existence of relationships among their outputs and operating conditions as well as to define suitable methods for signal processing. Those aspects have been addressed by means of a thorough experimental programme in a model industrial burner. Parametric analysis of flame signals recorded for a broad range of operating conditions revealed that they varied widely with the actual combustion state. In order to perform a systematic study, different correlation techniques were tried. Multiple regression methods provided some insight into mutual influences among different variables, although only in case of linear dependences. Artificial neural networks have been used as a more versatile type of algorithms, suitable for complex functional forms between input and output variables. Remarkably good results were obtained when NOx emissions or some burner settings were estimated from selected features of the flame signals, supporting their applicability for the development of advanced diagnostic methods in combustion processes. 40 refs., 13 figs., 3 tabs.

  5. Premixing quality and flame stability: A theoretical and experimental study

    Science.gov (United States)

    Radhakrishnan, K.; Heywood, J. B.; Tabaczynski, R. J.

    1979-01-01

    Models for predicting flame ignition and blowout in a combustor primary zone are presented. A correlation for the blowoff velocity of premixed turbulent flames is developed using the basic quantities of turbulent flow, and the laminar flame speed. A statistical model employing a Monte Carlo calculation procedure is developed to account for nonuniformities in a combustor primary zone. An overall kinetic rate equation is used to describe the fuel oxidation process. The model is used to predict the lean ignition and blow out limits of premixed turbulent flames; the effects of mixture nonuniformity on the lean ignition limit are explored using an assumed distribution of fuel-air ratios. Data on the effects of variations in inlet temperature, reference velocity and mixture uniformity on the lean ignition and blowout limits of gaseous propane-air flames are presented.

  6. An Overview of Combustion Mechanisms and Flame Structures for Advanced Solid Propellants

    Science.gov (United States)

    Beckstead, M. W.

    2000-01-01

    Ammonium perchlorate (AP) and cyclotretamethylenetetranitramine (HMX) are two solid ingredients often used in modern solid propellants. Although these two ingredients have very similar burning rates as monopropellants, they lead to significantly different characteristics when combined with binders to form propellants. Part of the purpose of this paper is to relate the observed combustion characteristics to the postulated flame structures and mechanisms for AP and HMX propellants that apparently lead to these similarities and differences. For AP composite, the primary diffusion flame is more energetic than the monopropellant flame, leading to an increase in burning rate over the monopropellant rate. In contrast the HMX primary diffusion flame is less energetic than the HMX monopropellant flame and ultimately leads to a propellant rate significantly less than the monopropellant rate in composite propellants. During the past decade the search for more energetic propellants and more environmentally acceptable propellants is leading to the development of propellants based on ingredients other than AP and HMX. The objective of this paper is to utilize the more familiar combustion characteristics of AP and HMX containing propellants to project the combustion characteristics of propellants made up of more advanced ingredients. The principal conclusion reached is that most advanced ingredients appear to burn by combustion mechanisms similar to HMX containing propellants rather than AP propellants.

  7. Flame experiments at the advanced light source: new insights into soot formation processes.

    Science.gov (United States)

    Hansen, Nils; Skeen, Scott A; Michelsen, Hope A; Wilson, Kevin R; Kohse-Höinghaus, Katharina

    2014-01-01

    The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory(1-4). This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range(5,6). The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species' profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates(7). The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles(4). The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation

  8. Flame experiments at the advanced light source: new insights into soot formation processes.

    Science.gov (United States)

    Hansen, Nils; Skeen, Scott A; Michelsen, Hope A; Wilson, Kevin R; Kohse-Höinghaus, Katharina

    2014-01-01

    The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory(1-4). This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range(5,6). The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species' profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates(7). The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles(4). The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation

  9. Recent Advances for Flame Retardancy of Textiles Based on Phosphorus Chemistry

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2016-08-01

    Full Text Available This paper aims at updating the progress on the phosphorus-based flame retardants specifically designed and developed for fibers and fabrics (particularly referring to cotton, polyester and their blends over the last five years. Indeed, as clearly depicted by Horrocks in a recent review, the world of flame retardants for textiles is still experiencing some changes that are focused on topics like the improvement of its effectiveness and the replacement of toxic chemical products with counterparts that have low environmental impact and, hence, are more sustainable. In this context, phosphorus-based compounds play a key role and may lead, possibly in combination with silicon- or nitrogen-containing structures, to the design of new, efficient flame retardants for fibers and fabrics. Therefore, this review thoroughly describes the advances and the potentialities offered by the phosphorus-based products recently developed at a lab-scale, highlighting the current limitations, open challenges and some perspectives toward their possible exploitation at a larger scale.

  10. Chemical quality of surface water in the Flaming Gorge Reservoir area, Wyoming and Utah

    Science.gov (United States)

    Madison, R.J.; Waddell, Kidd M.

    1973-01-01

    Construction of Flaming Gorge Dam on the Green River by the U.S. Bureau of Reclamation started in 1959, and storage began in November 1962. A reconnaissance study was made during the period 1966-68 to determine the effects of the reservoir on the chemical quality of the effluent water and to describe the quality of the impounded water and inflowing water. The major inflow to the reservoir is from the Green River, which contributes an average of 81 percent of the water and 59 percent of the inflow load of dissolved solids. Together, Blacks Fork and Henrys Fork contribute an average of about 16 percent of the water and about 23 percent of the dissolved-solids load, whereas minor tributaries contribute approximately 3 percent of the total inflow water to the reservoir, but about 18 percent of the total incoming load of dissolved solids. The concentration of dissolved solids in the reservoir in October 1966 was about 150 mg/l (milligrams per liter) greater than the concentration of the 1962-66 inflow and in September 1968 about 95 mg/l greater than the concentration of the 1962-68 inflow. The increased concentration is due. mostly to leaching of minerals from the reservoir bottom. For the 1963-68 water years, about 1.2 million tons of dissolved solids was leached from inundated areas. The major observable difference between the chemical composition of the inflow during 1963-66 and that of the reservoir in 1966 is an increase in the percentage of sulfate and a decrease in the percentage of bicarbonate. Impoundment of water in Flaming Gorge Reservoir during the 1963-68 water years caused the concentration of dissolved solids in the river system to increase by 130 mg/l, or about 32 percent over what would have occurred without the reservoir. Evaporation accounted for an increase of 15 mg/l, and leaching accounted for an increase of 115 mg/l.

  11. Advances in Internet Quality of Service

    OpenAIRE

    Firoiu, Victor; Le Boudec, Jean-Yves; Towsley, Don; Zhang, Zhi-Li

    2001-01-01

    We describe recent advances in theories and architecture that support performance guarantees needed for quality of service networks. We start with deterministic computations and give applications to integrated services, differentiated services, and playback delays. We review the methods used for obtaining a scalable integrated services support, based on the concept of a stateless core. New probabilistic results that can be used for a statistical dimensioning of differentiated services are exp...

  12. Emissions and Char Quality of Flame-Curtain "Kon Tiki" Kilns for Farmer-Scale Charcoal/Biochar Production.

    Directory of Open Access Journals (Sweden)

    Gerard Cornelissen

    Full Text Available Pyrolysis of organic waste or woody materials yields charcoal, a stable carbonaceous product that can be used for cooking or mixed into soil, in the latter case often termed "biochar". Traditional kiln technologies for charcoal production are slow and without treatment of the pyrolysis gases, resulting in emissions of gases (mainly methane and carbon monoxide and aerosols that are both toxic and contribute to greenhouse gas emissions. In retort kilns pyrolysis gases are led back to a combustion chamber. This can reduce emissions substantially, but is costly and consumes a considerable amount of valuable ignition material such as wood during start-up. To overcome these problems, a novel type of technology, the Kon-Tiki flame curtain pyrolysis, is proposed. This technology combines the simplicity of the traditional kiln with the combustion of pyrolysis gases in the flame curtain (similar to retort kilns, also avoiding use of external fuel for start-up.A field study in Nepal using various feedstocks showed char yields of 22 ± 5% on a dry weight basis and 40 ± 11% on a C basis. Biochars with high C contents (76 ± 9%; n = 57, average surface areas (11 to 215 m2 g-1, low EPA16-PAHs (2.3 to 6.6 mg kg-1 and high CECs (43 to 217 cmolc/kg(average for all feedstocks, mainly woody shrubs were obtained, in compliance with the European Biochar Certificate (EBC.Mean emission factors for the flame curtain kilns were (g kg-1 biochar for all feedstocks; CO2 = 4300 ± 1700, CO = 54 ± 35, non-methane volatile organic compounds (NMVOC = 6 ± 3, CH4 = 30 ± 60, aerosols (PM10 = 11 ± 15, total products of incomplete combustion (PIC = 100 ± 83 and NOx = 0.4 ± 0.3. The flame curtain kilns emitted statistically significantly (p<0.05 lower amounts of CO, PIC and NOx than retort and traditional kilns, and higher amounts of CO2.With benefits such as high quality biochar, low emission, no need for start-up fuel, fast pyrolysis time and, importantly, easy and cheap

  13. Free Radical Imaging Techniques Applied to Hydrocarbon Flames Diagnosis

    Institute of Scientific and Technical Information of China (English)

    A. Caldeira-Pires

    2001-01-01

    This paper evaluates the utilization of free radical chemiluminescence imaging and tomographic reconstruction techniques to assess advanced information on reacting flows. Two different laboratory flow configurations were analyzed, including unconfined non-premixed jet flame measurements to evaluate flame fuel/air mixing patterns at the burner-port of a typical glass-furnace burner. The second case characterized the reaction zone of premixed flames within gas turbine combustion chambers, based on a laboratory scale model of a lean prevaporized premixed (LPP) combustion chamber.The analysis shows that advanced imaging diagnosis can provide new information on the characterization of flame mixing and reacting phenomena. The utilization of local C2 and CH chemiluminescence can assess useful information on the quality of the combustion process, which can be used to improve the design of practical combustors.

  14. Advancing predictive models for particulate formation in turbulent flames via massively parallel direct numerical simulations.

    Science.gov (United States)

    Bisetti, Fabrizio; Attili, Antonio; Pitsch, Heinz

    2014-08-13

    Combustion of fossil fuels is likely to continue for the near future due to the growing trends in energy consumption worldwide. The increase in efficiency and the reduction of pollutant emissions from combustion devices are pivotal to achieving meaningful levels of carbon abatement as part of the ongoing climate change efforts. Computational fluid dynamics featuring adequate combustion models will play an increasingly important role in the design of more efficient and cleaner industrial burners, internal combustion engines, and combustors for stationary power generation and aircraft propulsion. Today, turbulent combustion modelling is hindered severely by the lack of data that are accurate and sufficiently complete to assess and remedy model deficiencies effectively. In particular, the formation of pollutants is a complex, nonlinear and multi-scale process characterized by the interaction of molecular and turbulent mixing with a multitude of chemical reactions with disparate time scales. The use of direct numerical simulation (DNS) featuring a state of the art description of the underlying chemistry and physical processes has contributed greatly to combustion model development in recent years. In this paper, the analysis of the intricate evolution of soot formation in turbulent flames demonstrates how DNS databases are used to illuminate relevant physico-chemical mechanisms and to identify modelling needs.

  15. Advancing predictive models for particulate formation in turbulent flames via massively parallel direct numerical simulations

    KAUST Repository

    Bisetti, Fabrizio

    2014-07-14

    Combustion of fossil fuels is likely to continue for the near future due to the growing trends in energy consumption worldwide. The increase in efficiency and the reduction of pollutant emissions from combustion devices are pivotal to achieving meaningful levels of carbon abatement as part of the ongoing climate change efforts. Computational fluid dynamics featuring adequate combustion models will play an increasingly important role in the design of more efficient and cleaner industrial burners, internal combustion engines, and combustors for stationary power generation and aircraft propulsion. Today, turbulent combustion modelling is hindered severely by the lack of data that are accurate and sufficiently complete to assess and remedy model deficiencies effectively. In particular, the formation of pollutants is a complex, nonlinear and multi-scale process characterized by the interaction of molecular and turbulent mixing with a multitude of chemical reactions with disparate time scales. The use of direct numerical simulation (DNS) featuring a state of the art description of the underlying chemistry and physical processes has contributed greatly to combustion model development in recent years. In this paper, the analysis of the intricate evolution of soot formation in turbulent flames demonstrates how DNS databases are used to illuminate relevant physico-chemical mechanisms and to identify modelling needs. © 2014 The Author(s) Published by the Royal Society.

  16. Preharvest salicylic acid treatments to improve quality and postharvest life of table grapes (Vitis vinifera L.) cv. Flame Seedless.

    Science.gov (United States)

    Champa, W A Harindra; Gill, M I S; Mahajan, B V C; Arora, N K

    2015-06-01

    Significance of preharvest salicylic acid (SA) treatments on maturity, quality and postharvest life of grape cv. Flame Seedless were studied during two years. The experiment was performed on 12-year old own rooted, grapevines planted at 3 m × 3 m spacing trained on overhead system. Vines were treated with aqueous solutions of SA (0.0, 1.0, 1.5 and 2.0 mM) at pea stage and at veraison. After harvesting, clusters were divided into two lots in which one was subjected to initial quality evaluation, while the other was stored in cold room (3-4 °C, 90-95 % RH) for evaluation of postharvest quality. SA at the dose of 1.5 and 2.0 mM hastened berry maturity by 3 to 5 days, produced less compact bunches alongside larger berries in contrast to control and the lowest dose. The same doses effectively maintained peel colour, higher firmness, lower pectin methyl esterase activity and electrolyte leakage alongside suppressing degradation of TSS and TA during cold storage. These two doses also exhibited higher efficacy on maintaining anthocyanins, phenols and organoleptic properties while reducing weight loss, rachis browning and decay incidence. Correlation analysis demonstrated that many quality parameters are interdependent. In conclusion, preharvest spray of 1.5 mM SA proved to be an effective means of improving quality and extending postharvest life of grape cv. Flame Seedless. PMID:26028743

  17. Demonstration of new frequency-based flame monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    Khesin, M. [MK Engineering Inc., North Andover, MA (United States)

    1996-11-01

    Methods of flame monitoring and combustion diagnostics based on analysis of temporal frequency spectra of flame radiation are attracting growing attention. It has been demonstrated that valuable flame quality information can be extracted from the chaos of burner flames by applying advanced signal analysis. A new flame diagnostics system (Flamenco), based on the application of new signal processing algorithms, have been developed and tested. The system generates an array of statistical values correlating with main combustion parameters of individual burner flames. Along with the main system, several derivative software systems were developed to enhance the testing and analysis capabilities. This paper presents preliminary results of pilot-scale testing of the new system, conducted at a single-burner combustion test facility, with support of Forney Corporation. Pilot-scale testing was conducted on a 1.0 Mbtu/hr single-burner gas-fired boiler, equipped with analytical instrumentation to measure NOx, O{sub 2}, CO{sub 2} and CO. The tests were conducted for the full range of air flow changes at different loads. The results have proven that the new system generates output signals correlated with measured burner parameters, such as NOx and airflow. The new system offers an effective and economical new method of flame monitoring and combustion diagnostics, to facilitate balancing and adjustment of individual burners and it is applicable to both single and multi-burner installations.

  18. Methodology and Supporting Toolset Advancing Embedded Systems Quality

    DEFF Research Database (Denmark)

    Berger, Michael Stübert; Soler, José; Brewka, Lukasz Jerzy;

    2013-01-01

    Software quality is of primary importance in the development of embedded systems that are often used in safety-critical applications. Moreover, as the life cycle of embedded products becomes increasingly tighter, productivity and quality are simultaneously required and closely interrelated towards...... delivering competitive products. In this context, the MODUS (Methodology and supporting toolset advancing embedded systems quality) project aims to provide a pragmatic and viable solution that will allow SMEs to substantially improve their positioning in the embedded-systems development market. This paper...... will describe the MODUS project with focus on the technical methodologies that will be developed advancing embedded system quality....

  19. Quality of pathology reports for advanced ovarian cancer

    DEFF Research Database (Denmark)

    Verleye, Leen; Ottevanger, Petronella B; Kristensen, Gunnar B;

    2011-01-01

    To assess the quality of surgical pathology reports of advanced stage ovarian, fallopian tube and primary peritoneal cancer. This quality assurance project was performed within the EORTC-GCG 55971/NCIC-CTG OV13 study comparing primary debulking surgery followed by chemotherapy with neoadjuvant ch...

  20. Quality of pathology reports for advanced ovarian cancer

    DEFF Research Database (Denmark)

    Verleye, Leen; Ottevanger, Petronella B; Kristensen, Gunnar B;

    2011-01-01

    To assess the quality of surgical pathology reports of advanced stage ovarian, fallopian tube and primary peritoneal cancer. This quality assurance project was performed within the EORTC-GCG 55971/NCIC-CTG OV13 study comparing primary debulking surgery followed by chemotherapy with neoadjuvant...

  1. Advances in Intumescent Flame Retardation of Rubbers%橡胶膨胀型阻燃研究进展

    Institute of Scientific and Technical Information of China (English)

    王正洲; 孔清锋; 江平开

    2012-01-01

    Nowadays,flame retardants commonly used in rubbers are mainly halogen-containing compounds and/or their combination with antimony oxides.Due to the environmental concern and increasing prices of halogen-containing compounds,halogen-free flame retardation of rubbers has aroused a great attention in recent years.Incorporation of one kind of halogen-free flame-retardants alone into rubbers,such as phosphorus-containing compounds,phosphorus and nitrogen-containing compounds,and metal hydroxides etc.cannot meet stringent flame retardant requirements of some rubber products,i.e.conveyer belts.Intumescent flame retardants(IFRs) are considered to be a promising flame retardant system.In this paper,it was introduced that the development and mechanism of IFRs,research achievements of intumescent flame retardation of rubbers(i.e.SBR,NBR,NR,SR,etc.),and some existing problems and developing trend of intumescent flame retarded rubbers.%目前,橡胶的阻燃主要是采用含卤阻燃剂与氧化锑复合体系。近年来,由于对一些含卤阻燃剂的使用限制及价格因素使得橡胶的无卤阻燃引起了人们的广泛关注。在一些对阻燃性能要求比较高的橡胶制品(如输送带)中,采用单一类型的无卤阻燃剂,如磷类化合物、磷氮类化合物、金属氢氧化物等,通常是难以满足严格的阻燃要求。膨胀型阻燃体系被认为是具有较好发展前景的阻燃体系之一。文中主要介绍膨胀型阻燃剂的发展、阻燃机理,橡胶(如丁苯橡胶、天然橡胶、乙丙橡胶、硅橡胶等)膨胀型阻燃方面的研究进展,以及膨胀型阻燃橡胶目前存在的问题及未来发展方向。

  2. ADVANCES IN TRANSGENIC MAIZE FOR QUALITY IMPROVEMENT

    Directory of Open Access Journals (Sweden)

    M.Rajendar Reddy

    2015-12-01

    Full Text Available Maize (Zea mays is a major food and animal feed worldwide and occupies a relevant place in the world economy and trade as an industrial grain crop. Currently more than 70% of maize production is used for food and feed; therefore, knowledge of genes involved in grain structure and chemical is important for improving the nutritional and food-making properties of maize. It is a good source of carbohydrates, fats, proteins, vitamins and minerals but deficient in two essential amino acids, Viz., lysine and tryptophan. To overcome this problem and to improve the above quality characters the maize breeders have followed different strategies like opaque 2, QPM and development of transgenic maize with improved quality characters. Finally we can conclude that the conventional breeding techniques and now plant biotechnology are helping meet the growing demand for food production, nutrition security while preserving our environment for future generations

  3. Contributions of CCLM to advances in quality control.

    Science.gov (United States)

    Kazmierczak, Steven C

    2013-01-01

    Abstract The discipline of laboratory medicine is relatively young when considered in the context of the history of medicine itself. The history of quality control, within the context of laboratory medicine, also enjoys a relatively brief, but rich history. Laboratory quality control continues to evolve along with advances in automation, measurement techniques and information technology. Clinical Chemistry and Laboratory Medicine (CCLM) has played a key role in helping disseminate information about the proper use and utility of quality control. Publication of important advances in quality control techniques and dissemination of guidelines concerned with laboratory quality control has undoubtedly helped readers of this journal keep up to date on the most recent developments in this field.

  4. Dramatic Advance in Quality in Flexographic Printing

    Directory of Open Access Journals (Sweden)

    Jochen Richter

    2004-12-01

    Full Text Available The enormous changes in flexography printing in recent years concerning the printing quality achievable cannot generally be ascribed to a single revolutionary invention, but are the result of continuous developments to the complete system. Thus the direct drive technology in all machine types and its associated advantages in terms of printing length corrections has become established since drupa 2000. The race for ever finer raster rolls has also been completed to the benefit of improvements in bowl geometry and in ceramic surfaces. Clearly improved colour transfer behaviour has become feasible as a result. In a closely intermeshed system such as flexography printing this naturally has to have an effect on the printing colours used. Further improvements in bonding agents and pigment concentrations now allow users to print ever thinner colour layers while maintaining all of the required authenticities.Furthermore, it has become possible to reduce additional disturbing characteristics in the UV colour area, such as the unpleasant odour. While the digital imaging of printing plates has primarily been improved in terms of economic efficiency by the use of up to eight parallel laser beams, extreme improvements in the system are noticeable especially in the area of directly engraved printing moulds. Whereas many still dismissed directly engraved polymer plates at the last drupa as a laboratory system, the first installation was recently placed on the market a mere three years later. A further noteworthy innovation of recent years that has reached market maturity is thin sleeve technology, which combines the advantages of a photopolymer plate with a round imaged printing mould. There are no high sleeve costs for each printing mould, except for one-off cost for an adapter sleeve. To conclude, it can be said that although flexography printing has experienced many new features in the time between drupa 2000 and today, it still has enormous potential for

  5. Recent Advances and Future Directions for Quality Engineering

    DEFF Research Database (Denmark)

    Vining, Geoff; Kulahci, Murat; Pedersen, Søren

    2015-01-01

    The origins of quality engineering are in manufacturing, where quality engineers apply basic statistical methodologies to improve the quality and productivity of products and processes. In the past decade, people have discovered that these methodologies are effective for improving almost any type...... of system or process, such as financial, health care, and supply chains. This paper begins with a review of key advances and trends within quality engineering over the past decade. The second part uses the first part as a foundation to outline new application areas for the field. It also discusses how...... quality engineering needs to evolve in order to make significant contributions to these new areas. © 2015 The Authors Quality and Reliability Engineering International Published by John Wiley & Sons Ltd....

  6. Rocket flames

    Directory of Open Access Journals (Sweden)

    W. M. Vaidya

    1952-09-01

    Full Text Available Among the important parameters which characterize the rocket flames are the (1 velocity, (2 pressure, (3 temperature of the exhaust gases and (4 the nature of chemical reactions in the flame of such gases. For the determination of these quantities ordinary methods fail because the flow of exhaust gases is supersonic in character. An introduction of a probe or any foreign body will create such strong disturbances in the supersonic flow that the readings of observing instruments will have no value. Spectroscopic methods are therefore eminently suitable because observations can be taken on the flame under running conditions.

  7. Advances in genomics for the improvement of quality in coffee.

    Science.gov (United States)

    Tran, Hue Tm; Lee, L Slade; Furtado, Agnelo; Smyth, Heather; Henry, Robert J

    2016-08-01

    Coffee is an important crop that provides a livelihood to millions of people living in developing countries. Production of genotypes with improved coffee quality attributes is a primary target of coffee genetic improvement programmes. Advances in genomics are providing new tools for analysis of coffee quality at the molecular level. The recent report of a genomic sequence for robusta coffee, Coffea canephora, is a major development. However, a reference genome sequence for the genetically more complex arabica coffee (C. arabica) will also be required to fully define the molecular determinants controlling quality in coffee produced from this high quality coffee species. Genes responsible for control of the levels of the major biochemical components in the coffee bean that are known to be important in determining coffee quality can now be identified by association analysis. However, the narrow genetic base of arabica coffee suggests that genomics analysis of the wild relatives of coffee (Coffea spp.) may be required to find the phenotypic diversity required for effective association genetic analysis. The genomic resources available for the study of coffee quality are described and the potential for the application of next generation sequencing and association genetic analysis to advance coffee quality research are explored. © 2016 Society of Chemical Industry. PMID:26919810

  8. Flame Length

    Data.gov (United States)

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

  9. Advanced spot quality analysis in two-colour microarray experiments

    Directory of Open Access Journals (Sweden)

    Vetter Guillaume

    2008-09-01

    Full Text Available Abstract Background Image analysis of microarrays and, in particular, spot quantification and spot quality control, is one of the most important steps in statistical analysis of microarray data. Recent methods of spot quality control are still in early age of development, often leading to underestimation of true positive microarray features and, consequently, to loss of important biological information. Therefore, improving and standardizing the statistical approaches of spot quality control are essential to facilitate the overall analysis of microarray data and subsequent extraction of biological information. Findings We evaluated the performance of two image analysis packages MAIA and GenePix (GP using two complementary experimental approaches with a focus on the statistical analysis of spot quality factors. First, we developed control microarrays with a priori known fluorescence ratios to verify the accuracy and precision of the ratio estimation of signal intensities. Next, we developed advanced semi-automatic protocols of spot quality evaluation in MAIA and GP and compared their performance with available facilities of spot quantitative filtering in GP. We evaluated these algorithms for standardised spot quality analysis in a whole-genome microarray experiment assessing well-characterised transcriptional modifications induced by the transcription regulator SNAI1. Using a set of RT-PCR or qRT-PCR validated microarray data, we found that the semi-automatic protocol of spot quality control we developed with MAIA allowed recovering approximately 13% more spots and 38% more differentially expressed genes (at FDR = 5% than GP with default spot filtering conditions. Conclusion Careful control of spot quality characteristics with advanced spot quality evaluation can significantly increase the amount of confident and accurate data resulting in more meaningful biological conclusions.

  10. Water quality management of aquifer recharge using advanced tools.

    Science.gov (United States)

    Lazarova, Valentina; Emsellem, Yves; Paille, Julie; Glucina, Karl; Gislette, Philippe

    2011-01-01

    Managed aquifer recharge (MAR) with recycled water or other alternative resources is one of the most rapidly growing techniques that is viewed as a necessity in water-short areas. In order to better control health and environmental effects of MAR, this paper presents two case studies demonstrating how to improve water quality, enable reliable tracing of injected water and better control and manage MAR operation in the case of indirect and direct aquifer recharge. Two water quality management strategies are illustrated on two full-scale case studies, including the results of the combination of non conventional and advanced technologies for water quality improvement, comprehensive sampling and monitoring programs including emerging pollutants, tracer studies using boron isotopes and integrative aquifer 3D GIS hydraulic and hydrodispersive modelling.

  11. Advanced methods of quality control in nuclear fuel fabrication

    International Nuclear Information System (INIS)

    Under pressure of current economic and electricity market situation utilities implement more demanding fuel utilization schemes including higher burn ups and thermal rates, longer fuel cycles and usage of Mo fuel. Therefore, fuel vendors have recently initiated new R and D programmes aimed at improving fuel quality, design and materials to produce robust and reliable fuel. In the beginning of commercial fuel fabrication, emphasis was given to advancements in Quality Control/Quality Assurance related mainly to product itself. During recent years, emphasis was transferred to improvements in process control and to implementation of overall Total Quality Management (TQM) programmes. In the area of fuel quality control, statistical control methods are now widely implemented replacing 100% inspection. This evolution, some practical examples and IAEA activities are described in the paper. The paper presents major findings of the latest IAEA Technical Meetings (TMs) and training courses in the area with emphasis on information received at the TM and training course held in 1999 and other latest publications to provide an overview of new developments in process/quality control, their implementation and results obtained including new approaches to QC

  12. Knowledge Management Platform in Advanced Product Quality Planning

    Science.gov (United States)

    Chiliban, Bogdan; Baral, Lal Mohan; Kifor, Claudiu

    2014-12-01

    Knowledge is an essential part of organizational competitiveness. This vital resource must be managed correctly within organizations in order to achieve desired performance levels within all undertakings. The process of managing knowledge is a very difficult one due to the illusive nature of the resource itself. Knowledge is stored within every aspect of an organization starting from people and ending with documents and processes. The Knowledge Management Platform is designed as a facilitator for managers and employees in all endeavours knowledge related within the Advanced Product Quality Planning Procedure

  13. High quality mask storage in an advanced Logic-Fab

    Science.gov (United States)

    Jähnert, Carmen; Fritsche, Silvio

    2012-02-01

    High efficient mask logistics as well as safe and high quality mask storage are essential requirements within an advanced lithography area of a modern logic waferfab. Fast operational availability of the required masks at the exposure tool with excellent mask condition requires a safe mask handling, safeguarding of high mask quality over the whole mask usage time without any quality degradation and an intelligent mask logistics. One big challenge is the prevention of haze on high advanced phase shift masks used in a high volume production line for some thousands of 248nm or 193nm exposures. In 2008 Infineon Dresden qualified a customer specific developed semi-bare mask storage system from DMSDynamic Micro Systems in combination with a high advanced mask handling and an interconnected complex logistic system. This high-capacity mask storage system DMS M1900.22 for more than 3000 masks with fully automated mask and box handling as well as full-blown XCDA purge has been developed and adapted to the Infineon Lithotoollandscape using Nikon and SMIF reticle cases. Advanced features for ESD safety and mask security, mask tracking via RFID and interactions with the exposure tools were developed and implemented. The stocker is remote controlled by the iCADA-RSM system, ordering of the requested mask directly from the affected exposure tool allows fast access. This paper discusses the advantages and challenges for this approach as well as the practical experience gained during the implementation of the new system which improves the fab performance with respect to mask quality, security and throughput. Especially the realization of an extremely low and stable humidity level in addition with a well controlled air flow at each mask surface, preventing masks from haze degradation and particle contamination, turns out to be a notable technical achievement. The longterm stability of haze critical masks has been improved significantly. Relevant environmental parameters like

  14. Quality-of-life assessment in advanced cancer.

    LENUS (Irish Health Repository)

    Donnelly, S

    2000-07-01

    In the past 5 years, quality-of-life (QOL) assessment measures such as the McGill, McMaster, Global Visual Analogue Scale, Assessment of QOL at the End of Life, Life Evaluation Questionnaire, and Hospice QOL Index have been devised specifically for patients with advanced cancer. The developers of these instruments have tried to respond to the changing needs of this specific population, taking into account characteristics including poor performance status, difficulty with longitudinal study, rapidly deteriorating physical condition, and change in relevant issues. Emphasis has been placed on patient report, ease and speed of completion, and the existential domain or meaning of life. Novel techniques in QOL measurement have also been adapted for palliative care, such as judgment analysis in the Schedule for the Evaluation of Individual Quality of Life. It is generally agreed that a single tool will not cover all QOL assessment needs.

  15. Advances in the study of current-use non-PBDE brominated flame retardants and dechlorane plus in the environment and humans

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The fate of the high production volume,currently in use,and not regulated non-polybrominated diphenyl ether(PBDE) flame retardants,such as tetrabromobisphenol A(TBBPA) ,hexabromocyclododecane(HBCD) and dechlorane plus(DP),and the alternative flame retardants of PBDE,such as BTBPE and DBDPE,in the environment has attracted increasing attention and aroused concern due to the increasing regulation and phasing-out of PBDEs.This paper reviews the distribution,bioaccumulation,human exposure and environmental behavior of those non-PBDE flame retardants in various environmental compartments.The data gaps and needs for future research are discussed.

  16. Study of Hydrogen flame annealed Au thin-film surface morphology, integrity and film quality on various substrate surfaces

    Science.gov (United States)

    Schell, Michael; Senevirathne, Indrajith

    2013-03-01

    Au thin-films have many applications in both industry and proof of concept investigations in device engineering. Typical Au depositions on substrate give rise to Stanski-Krastanov (SK) like growth while Frank-van der Merwe (FM) mode like growth is desired in many molecular self assembly and other engineering applications. Au films are magnetron sputter deposited at 100mtorr at low deposition rates (~ 1ML/min) on cleaved/fresh mica, glass microscopy slides and Si surfaces. Samples are hydrogen flame annealed to facilitate surface diffusion with minimal film contamination. Resulting Au surfaces were investigated and compared against purchased Au(111) on mica (standard) surface. Regular and custom built hydrophilic and hydrophobic AFM (Atomic Force Microcopy) probes were used in contact, and non contact AFM with topography and phase imaging to access the contamination and surface defects. Surface integrity, roughness, corrugation and morphology on Au surfaces were estimated. LHU Nanotechnology Program, PASSHE FPDC (LOU # 2010-LHU-03).

  17. Quality Nursing Care for Hospitalized Patients with Advanced Illness: Concept Development

    OpenAIRE

    Izumi, Shigeko; Baggs, Judith G.; Knafl, Kathleen A.

    2010-01-01

    The quality of nursing care as perceived by hospitalized patients with advanced illness has not been examined. A concept of quality nursing care for this population was developed by integrating the literature on constructs defining quality nursing care with empirical findings from interviews of 16 patients with advanced illness. Quality nursing care was characterized as competence and personal caring supported by professionalism and delivered with an appropriate demeanor. Although the attribu...

  18. Experiment and Simulation of Autoignition in Jet Flames and its Relevance to Flame Stabilization and Structure

    KAUST Repository

    Al-Noman, Saeed M.

    2016-06-01

    Autoignition characteristics of pre-vaporized iso-octane, primary reference fuels, gasolines, and dimethyl ether (DME) have been investigated experimentally in a coflow with elevated temperature of air. With the coflow air at relatively low initial temperatures below autoignition temperature Tauto, an external ignition source was required to stabilize the flame. Non-autoignited lifted flames had tribrachial edge structures and their liftoff heights correlated well with the jet velocity scaled by the stoichiometric laminar burning velocity, indicating the importance of the edge propagation speed on flame stabilization balanced with local flow velocity. At high initial temperatures over Tauto, the autoignited flames were stabilized without requiring an external ignition source. The autoignited lifted flames exhibited either tribrachial edge structures or Mild combustion behaviors depending on the level of fuel dilution. For the iso-octane and n-heptane fuels, two distinct transition behaviors were observed in the autoignition regime from a nozzle-attached flame to a lifted tribrachial-edge flame and then a sudden transition to lifted Mild combustion as the jet velocity increased at a certain fuel dilution level. The liftoff data of the autoignited flames with tribrachial edges were analyzed based on calculated ignition delay times for the pre-vaporized fuels. Analysis of the experimental data suggested that ignition delay time may be much less sensitive to initial temperature under atmospheric pressure conditions as compared with predictions. For the gasoline fuels for advanced combustion engines (FACEs), and primary reference fuels (PRFs), autoignited liftoff data were correlated with Research Octane Number and Cetane Number. For the DME fuel, planar laser-induced fluorescence (PLIF) of formaldehyde (CH2O) and CH* chemiluminescence were visualized qualitatively. In the autoignition regime for both tribrachial structure and mild combustion, formaldehyde were found

  19. Diagnostics and Control of Natural Gas-Fired furnaces via Flame Image Analysis using Machine Vision & Artificial Intelligence Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Shahla Keyvan

    2005-12-01

    A new approach for the detection of real-time properties of flames is used in this project to develop improved diagnostics and controls for natural gas fired furnaces. The system utilizes video images along with advanced image analysis and artificial intelligence techniques to provide virtual sensors in a stand-alone expert shell environment. One of the sensors is a flame sensor encompassing a flame detector and a flame analyzer to provide combustion status. The flame detector can identify any burner that has not fired in a multi-burner furnace. Another sensor is a 3-D temperature profiler. One important aspect of combustion control is product quality. The 3-D temperature profiler of this on-line system is intended to provide a tool for a better temperature control in a furnace to improve product quality. In summary, this on-line diagnostic and control system offers great potential for improving furnace thermal efficiency, lowering NOx and carbon monoxide emissions, and improving product quality. The system is applicable in natural gas-fired furnaces in the glass industry and reheating furnaces used in steel and forging industries.

  20. An old flame

    Science.gov (United States)

    Thompson, Frank

    2014-07-01

    Flames are seen more often in chemistry than in physics laboratories. However, as a continuation of the previous colourful demonstration of a levitating Bunsen flame described recently in this journal (De Carvalho 2012 Phys Educ. 47 517), two short experiments are reported. Firstly, flame rectification is investigated and secondly, the electrical potential around a charged object is measured.

  1. Advances in Application of Models in Soil Quality Evaluation

    Institute of Scientific and Technical Information of China (English)

    SI Zhi-guo; WANG Ji-jie; YU Yuan-chun; LIANG Guan-feng; CHEN Chang-ren; SHU Hong-lan

    2012-01-01

    Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety of evaluation methods,but it still lacks universal soil quantity evaluation models and methods.In this paper,the applications and prospects of grey relevancy comprehensive evaluation model,attribute hierarchical model,fuzzy comprehensive evaluation model,matter-element model,RAGA-based PPC /PPE model and GIS model in soil quality evaluation are reviewed.

  2. Flame structure of methane inverse diffusion flame

    KAUST Repository

    Elbaz, Ayman M.

    2014-07-01

    This paper presents high speed images of OH-PLIF at 10. kHz simultaneously with 2D PIV (particle image velocimetry) measurements collected along the entire length of an inverse diffusion flame with circumferentially arranged methane fuel jets. For a fixed fuel flow rate, the central air jet Re was varied, leading to four air to fuel velocity ratios, namely Vr = 20.7, 29, 37.4 and 49.8. A double flame structure could be observed composed of a lower fuel entrainment region and an upper mixing and intense combustion region. The entrainment region was enveloped by an early OH layer, and then merged through a very thin OH neck to an annular OH layer located at the shear layer of the air jet. The two branches of this annular OH layer broaden as they moved downstream and eventfully merged together. Three types of events were observed common to all flames: breaks, closures and growing kernels. In upstream regions of the flames, the breaks were counterbalanced by flame closures. These breaks in OH signal were found to occur at locations where locally high velocity flows were impinging on the flame. As the Vr increased to 37.4, the OH layers became discontinuous over the downstream region of the flame, and these regions of low or no OH moved upstream. With further increases in Vr, these OH pockets act as flame kernels, growing as they moved downstream, and became the main mechanism for flame re-ignition. Along the flame length, the direction of the two dimensional principle compressive strain rate axis exhibited a preferred orientation of approximately 45° with respect to the flow direction. Moreover, the OH zones were associated with elongated regions of high vorticity. © 2013 Elsevier Inc.

  3. Quality Control of the Flame Normalizing in Rail Flash-butt Welded Joint%钢轨闪光焊接头火焰正火的质量控制

    Institute of Scientific and Technical Information of China (English)

    周涛

    2016-01-01

    Flame normalizing is one of the methods to improve the mechanical properties of the welded joint. This paper summarizes the construction experience, on the basis of tests by means of theoretical analysis, obtains a specific set of quality control measures of flame normalizing in rail flash-butt welded joint.%正火是继钢轨焊接结束后一种重要的提高其机械性能的方法,本文总结以往的施工经验,在试验的基础上通过理论分析,得出一套具体的钢轨焊接火焰正火的质量控制措施。

  4. Research Advance in Pollution of Flame Retardant Tetrabromobisphenol-A to Environment%阻燃剂四溴双酚-A环境污染研究进展

    Institute of Scientific and Technical Information of China (English)

    武焕阳

    2011-01-01

    随着多溴联苯醚(PBDEs)生产的逐渐限制和淘汰,目前尚未被限制且大量生产的非PBDEs阻燃剂,如四溴双酚-A(TBBP-A),在环境中的污染现状逐渐引起重视.该文介绍了在不同环境下TBBP-A的分布、生物富集、人类暴露和环境行为影响.%Along with the gradual limit and elimination of polybrominated diphenyl ether (PBDEs) production, the environment pollution status of un- regulated and mass -producing non -PBDEs flame retardants, such as tetrabromobisphenol -A (TBBP -A) has attracted increasing attention and concern. This paper reviews the distribution, bioaccumulation, human exposure and environmental behavior of flame retardant TBBP - A in various environments.

  5. Quality of experience advanced concepts, applications and methods

    CERN Document Server

    Raake, Alexander

    2014-01-01

    This pioneering book develops definitions and concepts related to Quality of Experience in the context of multimedia- and telecommunications-related applications, systems and services, and applies these to various fields of communication and media technologies. The editors bring together numerous key-protagonists of the new discipline “Quality of Experience” and combine the state-of-the-art knowledge in one single volume. 

  6. ANALYSIS ON EFFLUENT WATER QUALITY AND ELECTRICITY CONSUMPTION AFTER INTRODUCING ADVANCED SEWAGE TREATMENT

    Science.gov (United States)

    Shiojiri, Yasuo; Maekawa, Shunich

    We analyze effluent water quality and electricity consumption after in troducing advanced treatment in sewage treatment plant. We define 'advanced treatment ratio' as volume of treated water through advanced treatment processes divided by total volume of treated water in plant. Advanced treatment ratio represents degree of introducing advanced treatment. We build two types of equation. One represents relation between effluent water quality and advanced treatment ratio, the other between electricity consumption and advanced treatment ratio. Each equation is fitted by least squares on 808 samples: 8 fiscal years operation data of 101 plants working in Kanagawa, Tokyo, Saitama and Chiba areas, and coefficient of advanced treatment ratio is estimated. The result is as follows. (1) After introducing advanced treatment aimed at nitrogen removal, T-N in effluent water decreases by 51.3% and electricity consum ption increases by 52.2%. (2) After introducing advanced treatment aimed at phosphorus removal, T-P in effluent water decreases by 27.8%. Using the above result, we try prioritizing 71 plants in Tokyo Bay watershed about raising advanced treatment ratio, so that, in total, pollutant in effluent water decreases with minimized increase of electricity consumption.

  7. Field Effects of Buoyancy on Lean Premixed Turbulent Flames

    Science.gov (United States)

    Cheng, R. K.; Johnson, M. R.; Greenberg, P. S.; Wernet, M. P.

    2003-01-01

    The study of field effects of buoyancy on premixed turbulent flames is directed towards the advancement of turbulent combustion theory and the development of cleaner combustion technologies. Turbulent combustion is considered the most important unsolved problem in combustion science and laboratory studies of turbulence flame processes are vital to theoretical development. Although buoyancy is dominant in laboratory flames, most combustion models are not yet capable to consider buoyancy effects. This inconsistency has impeded the validation of theories and numerical simulations with experiments. Conversely, the understanding of buoyancy effects is far too limited to help develop buoyant flame models. Our research is also relevant to combustion technology because lean premixed combustion is a proven method to reduce the formation of oxides of nitrogen (NOx). In industrial lean premixed combustion systems, their operating conditions make them susceptible to buoyancy thus affecting heat distribution, emissions, stability, flashback and blowoff. But little knowledge is available to guide combustion engineers as to how to avoid or overcome these problems. Our hypothesis is that through its influence on the mean pressure field, buoyancy has direct and indirect effects on local flame/turbulence interactions. Although buoyancy acts on the hot products in the farfield the effect is also felt in the nearfield region upstream of the flame. These changes also influence the generation and dissipation of turbulent kinetic energy inside the flame brush and throughout the flowfield. Moreover, the plume of an open flame is unstable and the periodic fluctuations make additional contributions to flame front dynamics in the farfield. Therefore, processes such as flame wrinkling, flow acceleration due to heat release and flame- generated vorticity are all affected. Other global flame properties (e.g. flame stabilization limits and flame speed) may all be coupled to buoyancy. This

  8. Reconstructing the Cryptanalytic Attack behind the Flame Malware

    NARCIS (Netherlands)

    Fillinger, M.J.

    2013-01-01

    Flame was an advanced malware, used for espionage, which infected computers running a Microsoft Windows operating system. Once a computer in a local network was infected, Flame could spread to the other computers in the network via Windows Update, disguised as a security patch from Microsoft. Window

  9. The new advances in radiotherapy technique challenges of quality assurance

    International Nuclear Information System (INIS)

    What is Quality Assurance (QA)? This is all those planned and systematic actions necessary to provide confidence that a product or service will satisfy given requirements for quality. ISO 9000. It is the overall process which is supported by quality control activities. While, quality control describes the actual mechanisms and procedures by which one can assure quality. Consequences for radiotherapy A good acceptance testing and commissioning program is fundamental for any QA activities QA applies to both physical and clinical aspects of the treatment Treatment records must be kept of all relevant aspects of the treatment - including -Session and Summary Record information -Records all treatment parameters -Dose Calculations -Dose Measurements Particular emphasis is placed on QA of dosimetry A QA system itself and its outcomes must be critically reviewed. External audits are recommended to verify that the checks are not only done but that they also achieve what they are supposed to do Every good system requires an independent look at times A Comprehensive QA Program typically comprises Quality Assurance Committee, Policies and Procedures Manual, Quality Assurance team, Quality audit, Resources Introduction,..OBI in general. The On-Board Imager system is designed to correct for motion and setup errors of patients undergoing radiation therapy. It provides three imaging modes: Two-dimensional 2-D radiographic acquisition, Fluoroscopic image acquisition, and Three-dimensional 3-D cone-beam computed tomography CBCT acquisition. The fluoroscopic images are used to verify the gating thresholds of the respiratory gating system to account for intra-fraction i.e. respiratory motion. The radiographic images manage inter-fractional motion and setup errors. Using the 2D2DMatch and 3D3DMatch analysis tools a user can register the acquired kV or CBCT images with their associated reference image like DRR or planning CT for CBCT. Couch corrections are then downloaded to the linear

  10. Recent advances in omic technologies for meat quality management.

    Science.gov (United States)

    Picard, B; Lebret, B; Cassar-Malek, I; Liaubet, L; Berri, C; Le Bihan-Duval, E; Hocquette, J F; Renand, G

    2015-11-01

    The knowledge of the molecular organization of living organisms evolved considerably during the last years. The methodologies associated also progressed with the development of the high-throughput sequencing (SNP array, RNAseq, etc.) and of genomic tools allowing the simultaneous analysis of hundreds or thousands of genes, proteins or metabolites. In farm animals, some proteins, mRNAs or metabolites whose abundance has been associated with meat quality traits have been detected in pig, cattle, chicken. They constitute biomarkers for the assessment and prediction of qualities of interest in each species, with potential biomarkers across species. The ongoing development of rapid methods will allow their use for decision-making and management tools in slaughterhouses, to better allocate carcasses or cuts to the appropriate markets. Besides, their application on living animals will help to improve genetic selection and to adapt a breeding system to fulfill expected quality level. The ultimate goal is to propose effective molecular tools for the management of product quality in meat production chains.

  11. Shapes of Buoyant and Nonbuoyant Methane Laminar Jet Diffusion Flames

    Science.gov (United States)

    Sunderland, Peter B.; Yuan, Zeng-Guang; Urban, David L.

    1997-01-01

    Laminar gas jet diffusion flames represent a fundamental combustion configuration. Their study has contributed to numerous advances in combustion, including the development of analytical and computational combustion tools. Laminar jet flames are pertinent also to turbulent flames by use of the laminar flamelet concept. Investigations into the shapes of noncoflowing microgravity laminar jet diffusion flames have primarily been pursued in the NASA Lewis 2.2-second drop tower, by Cochran and coworkers and by Bahadori and coworkers. These studies were generally conducted at atmospheric pressure; they involved soot-containing flames and reported luminosity lengths and widths instead of the flame-sheet dimensions which are of Greater value to theory evaluation and development. The seminal model of laminar diffusion flames is that of Burke and Schumann, who solved the conservation of momentum equation for a jet flame in a coflowing ambient by assuming the velocity of fuel, oxidizer and products to be constant throughout. Roper and coworkers improved upon this model by allowing for axial variations of velocity and found flame shape to be independent of coflow velocity. Roper's suggestion that flame height should be independent of gravity level is not supported by past or present observations. Other models have been presented by Klajn and Oppenheim, Markstein and De Ris, Villermaux and Durox, and Li et al. The common result of all these models (except in the buoyant regime) is that flame height is proportional to fuel mass flowrate, with flame width proving much more difficult to predict. Most existing flame models have been compared with shapes of flames containing soot, which is known to obscure the weak blue emission of flame sheets. The present work involves measurements of laminar gas jet diffusion flame shapes. Flame images have been obtained for buoyant and nonbuoyant methane flames burning in quiescent air at various fuel flow-rates, burner diameters and ambient

  12. Recent Advances in Point-of-Access Water Quality Monitoring

    Science.gov (United States)

    Korostynska, O.; Arshak, K.; Velusamy, V.; Arshak, A.; Vaseashta, Ashok

    Clean water is one of our most valuable natural resources. In addition to providing safe drinking water it assures functional ecosystems that support fisheries and recreation. Human population growth and its associated increased demands on water pose risks to maintaining acceptable water quality. It is vital to assess source waters and the aquatic systems that receive inputs from industrial waste and sewage treatment plants, storm water systems, and runoff from urban and agricultural lands. Rapid and confident assessments of aquatic resources form the basis for sound environmental management. Current methods engaged in tracing the presence of various bacteria in water employ bulky laboratory equipment and are time consuming. Thus, real-time water quality monitoring is essential for National and International Health and Safety. Environmental water monitoring includes measurements of physical characteristics (e.g. pH, temperature, conductivity), chemical parameters (e.g. oxygen, alkalinity, nitrogen and phosphorus compounds), and abundance of certain biological taxa. Monitoring could also include assays of biological activity such as alkaline phosphatase, tests for toxins such as microcystins and direct measurements of pollutants such as heavy metals or hydrocarbons. Real time detection can significantly reduce the level of damage and also the cost to remedy the problem. This paper presents overview of state-of-the-art methods and devices used for point-of-access water quality monitoring and suggest further developments in this area.

  13. DATA ANALYSIS TECHNIQUES IN SERVICE QUALITY LITERATURE: ESSENTIALS AND ADVANCES

    Directory of Open Access Journals (Sweden)

    Mohammed naved Khan

    2013-05-01

    Full Text Available Academic and business researchers have for long debated on the most appropriate data analysis techniques that can be employed in conducting empirical researches in the domain of services marketing. On the basis of an exhaustive review of literature, the present paper attempts to provide a concise and schematic portrayal of generally followed data analysis techniques in the field of services quality literature. Collectively, the extant literature suggests that there is a growing trend among researchers to rely on higher order multivariate techniques viz. confirmatory factor analysis, structural equation modeling etc. to generate and analyze complex models, while at times ignoring very basic and yet powerful procedures such as mean, t-Test, ANOVA and correlation. The marked shift in orientation of researchers towards using sophisticated analytical techniques can largely beattributed to the competition within the community of researchers in social sciences in general and those working in the area of service quality in particular as also growing demands of reviewers ofjournals. From a pragmatic viewpoint, it is expected that the paper will serve as a useful source of information and provide deeper insights to academic researchers, consultants, and practitionersinterested in modelling patterns of service quality and arriving at optimal solutions to increasingly complex management problems.

  14. Flame Holder System

    Science.gov (United States)

    Haskin, Henry H. (Inventor); Vasquez, Peter (Inventor)

    2013-01-01

    A flame holder system includes a modified torch body and a ceramic flame holder. Catch pin(s) are coupled to and extend radially out from the torch body. The ceramic flame holder has groove(s) formed in its inner wall that correspond in number and positioning to the catch pin(s). Each groove starts at one end of the flame holder and can be shaped to define at least two 90.degree.turns. Each groove is sized to receive one catch pin therein when the flame holder is fitted over the end of the torch body. The flame holder is then manipulated until the catch pin(s) butt up against the end of the groove(s).

  15. Diffusion Flame Stabilization

    Science.gov (United States)

    Takahashi, Fumiaki; Katta, Viswanath R.

    2007-01-01

    Diffusion flames are commonly used for industrial burners in furnaces and flares. Oxygen/fuel burners are usually diffusion burners, primarily for safety reasons, to prevent flashback and explosion in a potentially dangerous system. Furthermore, in most fires, condensed materials pyrolyze, vaporize, and burn in air as diffusion flames. As a result of the interaction of a diffusion flame with burner or condensed-fuel surfaces, a quenched space is formed, thus leaving a diffusion flame edge, which plays an important role in flame holding in combustion systems and fire spread through condensed fuels. Despite a long history of jet diffusion flame studies, lifting/blowoff mechanisms have not yet been fully understood, compared to those of premixed flames. In this study, the structure and stability of diffusion flames of gaseous hydrocarbon fuels in coflowing air at normal earth gravity have been investigated experimentally and computationally. Measurements of the critical mean jet velocity (U(sub jc)) of methane, ethane, or propane at lifting or blowoff were made as a function of the coflowing air velocity (U(sub a)) using a tube burner (i.d.: 2.87 mm) (Fig. 1, left). By using a computational fluid dynamics code with 33 species and 112 elementary reaction steps, the internal chemical-kinetic structures of the stabilizing region of methane and propane flames were investigated (Fig. 1, right). A peak reactivity spot, i.e., reaction kernel, is formed in the flame stabilizing region due to back-diffusion of heat and radical species against an oxygen-rich incoming flow, thus holding the trailing diffusion flame. The simulated flame base moved downstream under flow conditions close to the measured stability limit.

  16. Sandia National Laboratories Advanced Simulation and Computing (ASC) software quality plan : ASC software quality engineering practices Version 3.0.

    Energy Technology Data Exchange (ETDEWEB)

    Turgeon, Jennifer L.; Minana, Molly A.; Hackney, Patricia; Pilch, Martin M.

    2009-01-01

    The purpose of the Sandia National Laboratories (SNL) Advanced Simulation and Computing (ASC) Software Quality Plan is to clearly identify the practices that are the basis for continually improving the quality of ASC software products. Quality is defined in the US Department of Energy/National Nuclear Security Agency (DOE/NNSA) Quality Criteria, Revision 10 (QC-1) as 'conformance to customer requirements and expectations'. This quality plan defines the SNL ASC Program software quality engineering (SQE) practices and provides a mapping of these practices to the SNL Corporate Process Requirement (CPR) 001.3.6; 'Corporate Software Engineering Excellence'. This plan also identifies ASC management's and the software project teams responsibilities in implementing the software quality practices and in assessing progress towards achieving their software quality goals. This SNL ASC Software Quality Plan establishes the signatories commitments to improving software products by applying cost-effective SQE practices. This plan enumerates the SQE practices that comprise the development of SNL ASC's software products and explains the project teams opportunities for tailoring and implementing the practices.

  17. Influence of the radiation absorbed by micro particles on the flame propagation and combustion regimes

    CERN Document Server

    Ivanov, M F; Liberman, M A

    2015-01-01

    Thermal radiation of the hot combustion products usually does not influence noticeably the flame propagating through gaseous mixture. the situation is changed drastically in the presence even small concentration of particles, which absorb radiation, transfer the heat to the surrounding unburned gaseous mixture by means of heat conduction, so that the gas phase temperature in front of the advancing flame lags that of the particles. It is shown that radiative preheating of unreacted mixture ahead of the flame results in a modest increase of the advancing flame velocity for a highly reactive gaseous fuel, or to considerable increase of the flame velocity in the case of a slow reactive mixture. The effects of radiation preheating as stronger as smaller the normal flame velocity. The radiation heat transfer can become a dominant mechanism compared with molecular heat conduction, determining the structure and the speed of combustion wave in the case of a small enough velocity of the advancing flame. It is shown tha...

  18. Advanced monitoring of wastewater quality: data collection and data quality assurance

    DEFF Research Database (Denmark)

    Alferes, Janelcy; Lamaire-Chad, C.; Chhetri, Ravi Kumar;

    and in evaluating the impact of discharges on the receiving water bodies. As measurements are carried out under arduous conditions, practical implementation of such monitoring systems entails several challenges, and automation of data collection and data quality assessment has been recognised as a critical issue......Reliable water quality monitoring is increasingly recognised as an essential element of a strategy to reach current environmental quality objectives. In the last few years, continuous water quality monitoring has demonstrated to be useful in capturing the dynamics of sewer and wastewater systems....... In this paper, a data quality assessment strategy is presented to achieve efficient water quality monitoring in real-world scenarios. Next to practical aspects concerning installation and maintenance of sensors, the paper also presents a software tool aimed at assessing the quality of the data being collected...

  19. Independent contributors to overall quality of life in people with advanced cancer

    OpenAIRE

    M Rodríguez, A; Mayo, N. E.; Gagnon, B.

    2013-01-01

    Background: The definition of health for people with cancer is not focused solely on the physiology of illness and the length of life remaining, but is also concerned with improving the well-being and the quality of the life (QOL) remaining to be lived. This study aimed to identify the constructs most associated with QOL in people with advanced cancer. Methods: Two hundred three persons with recent diagnoses of different advanced cancers were evaluated with 65 variables representing individua...

  20. Advanced terahertz techniques for quality control and counterfeit detection

    Science.gov (United States)

    Ahi, Kiarash; Anwar, Mehdi

    2016-04-01

    This paper reports our invented methods for detection of counterfeit electronic. These versatile techniques are also handy in quality control applications. Terahertz pulsed laser systems are capable of giving the material characteristics and thus make it possible to distinguish between the materials used in authentic components and their counterfeit clones. Components with material defects can also be distinguished in section in this manner. In this work different refractive indices and absorption coefficients were observed for counterfeit components compared to their authentic counterparts. Existence of unexpected ingredient materials was detected in counterfeit components by Fourier Transform analysis of the transmitted terahertz pulse. Thicknesses of different layers are obtainable by analyzing the reflected terahertz pulse. Existence of unexpected layers is also detectable in this manner. Recycled, sanded and blacktopped counterfeit electronic components were detected as a result of these analyses. Counterfeit ICs with die dislocations were detected by depicting the terahertz raster scanning data in a coordinate plane which gives terahertz images. In the same manner, raster scanning of the reflected pulse gives terahertz images of the surfaces of the components which were used to investigate contaminant materials and sanded points on the surfaces. The results of the later technique, reveals the recycled counterfeit components.

  1. Hi-tech Flame

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Modern science plays a crucial role in lighting the Olympic flame on the world’s highest mountain when the world saw live telecasts of the Olympic flame burning onthe top of Mount Qomolangma(Mount Everest) at 9:17 on the morning of May 8, few realized the years of work and high level of technology that had

  2. State of Health and Quality of Life of Women at Advanced Age

    Science.gov (United States)

    Pinkas, Jarosław; Gujski, Mariusz; Humeniuk, Ewa; Raczkiewicz, Dorota; Bejga, Przemysław; Owoc, Alfred; Bojar, Iwona

    2016-01-01

    Background Evaluation of the state of health, quality of life, and the relationship between the level of the quality of life and health status in a group of women at an advanced age (90 years of age and older) in Poland. Material/Methods The study was conducted in 2014 in an all-Polish sample of 870 women aged 90 years and older. The research instruments were: the authors’ questionnaire and several standardized tests: Katz Index of Independence in Activities of Daily Living (Katz ADL), Abbreviated Mental Test Score (AMTS), and the World Health Organization Quality of Life (WHOQOL)-BREF. The results of the study were statistically analyzed using significant t-test for mean and regression analysis. Results The majority of women at an advanced age suffered from chronic pain (76%) and major geriatric problems such as hypoacusis (81%), visual disturbances (69%) and urinary incontinence (60%); the minority of women at an advanced age suffered from falls and fainting (39%), stool incontinence (17%), severe functional impairment (24%), and cognitive impairment (10%). On a scale of 1 to 5, women at an advanced age assessed positively for overall quality of life (mean 3.3), social relationships (3.5), and environment (3.2), but negatively for general health, physical health, and psychological health (2.7, 2.7, and 2.8, respectively). The presence of chronic pain and geriatric problems, including urinary and stool incontinences, falls and faint ing, visual disturbances and hypoacusis, significantly decreased overall quality of life; general health, physical health, psychological health, social relationships, and environment. Overall quality of life, general health, physical health, psychological health, social relationships, and environment was correlated with functional and cognitive impairments. Conclusions Quality of life of women at an advanced age decreased if chronic pain, major geriatric problems, or functional or cognitive impairments occurred. PMID:27580565

  3. Flat flame burner

    Energy Technology Data Exchange (ETDEWEB)

    Matsumura, Y.; Mitsudomi, H.

    1976-03-09

    Osaka Gas Co., Ltd.'s new flat-flame burner has an air-swirling chamber with a flame opening in one side so constructed that combustion gas is forced out from the flame opening in a spiral direction by the swirling air current within the air chamber. The orifice effect of permitting the flame to emanate from a small opening to an unconfined outer space assures formation of a flat flame spreading out over a very wide area, thereby ensuring very rapid, uniform and highly efficient heat treatment of an article to be heated. With the present invention, moreover, it is possible to materially reduce the thickness of the overall device.

  4. Unsteady Flame Embedding

    KAUST Repository

    El-Asrag, Hossam A.

    2011-01-01

    Direct simulation of all the length and time scales relevant to practical combustion processes is computationally prohibitive. When combustion processes are driven by reaction and transport phenomena occurring at the unresolved scales of a numerical simulation, one must introduce a dynamic subgrid model that accounts for the multiscale nature of the problem using information available on a resolvable grid. Here, we discuss a model that captures unsteady flow-flame interactions- including extinction, re-ignition, and history effects-via embedded simulations at the subgrid level. The model efficiently accounts for subgrid flame structure and incorporates detailed chemistry and transport, allowing more accurate prediction of the stretch effect and the heat release. In this chapter we first review the work done in the past thirty years to develop the flame embedding concept. Next we present a formulation for the same concept that is compatible with Large Eddy Simulation in the flamelet regimes. The unsteady flame embedding approach (UFE) treats the flame as an ensemble of locally one-dimensional flames, similar to the flamelet approach. However, a set of elemental one-dimensional flames is used to describe the turbulent flame structure directly at the subgrid level. The calculations employ a one-dimensional unsteady flame model that incorporates unsteady strain rate, curvature, and mixture boundary conditions imposed by the resolved scales. The model is used for closure of the subgrid terms in the context of large eddy simulation. Direct numerical simulation (DNS) data from a flame-vortex interaction problem is used for comparison. © Springer Science+Business Media B.V. 2011.

  5. Emerging technology: A key enabler for modernizing pharmaceutical manufacturing and advancing product quality.

    Science.gov (United States)

    O'Connor, Thomas F; Yu, Lawrence X; Lee, Sau L

    2016-07-25

    Issues in product quality have produced recalls and caused drug shortages in United States (U.S.) in the past few years. These quality issues were often due to outdated manufacturing technologies and equipment as well as lack of an effective quality management system. To ensure consistent supply of safe, effective and high-quality drug products available to the patients, the U.S. Food and Drug Administration (FDA) supports modernizing pharmaceutical manufacturing for improvements in product quality. Specifically, five new initiatives are proposed here to achieve this goal. They include: (i) advancing regulatory science for pharmaceutical manufacturing; (ii) establishing a public-private institute for pharmaceutical manufacturing innovation; (iii) creating incentives for investment in the technological upgrade of manufacturing processes and facilities; (iv) leveraging external expertise for regulatory quality assessment of emerging technologies; and (v) promoting the international harmonization of approaches for expediting the global adoption of emerging technologies. PMID:27260134

  6. Emerging technology: A key enabler for modernizing pharmaceutical manufacturing and advancing product quality.

    Science.gov (United States)

    O'Connor, Thomas F; Yu, Lawrence X; Lee, Sau L

    2016-07-25

    Issues in product quality have produced recalls and caused drug shortages in United States (U.S.) in the past few years. These quality issues were often due to outdated manufacturing technologies and equipment as well as lack of an effective quality management system. To ensure consistent supply of safe, effective and high-quality drug products available to the patients, the U.S. Food and Drug Administration (FDA) supports modernizing pharmaceutical manufacturing for improvements in product quality. Specifically, five new initiatives are proposed here to achieve this goal. They include: (i) advancing regulatory science for pharmaceutical manufacturing; (ii) establishing a public-private institute for pharmaceutical manufacturing innovation; (iii) creating incentives for investment in the technological upgrade of manufacturing processes and facilities; (iv) leveraging external expertise for regulatory quality assessment of emerging technologies; and (v) promoting the international harmonization of approaches for expediting the global adoption of emerging technologies.

  7. Flat flame burner

    Energy Technology Data Exchange (ETDEWEB)

    Matsumura, Y.; Mitsudomi, H.

    1976-02-24

    Osaka Gas Co., Ltd.'s new flat-flame heat-treatment burner offers lower material costs, reduced combustion noise, and elimination of the need for a high-pressure fuel gas to provide a high-velocity combustion burner. The flat-flame burner contains an air-swirling chamber with a flame opening in one side; the wall defining the flame opening has a small thickness around the opening and a flat outer face. This construction causes the combustion gas to be forced out from the flame opening in a spiral direction by the swirling air current within the air chamber; together with the orifice effect of permitting the flame to emanate from a small opening to an unconfined outer space, this helps assure the formation of a flat flame spreading out over a very wide area for very rapid, uniform, and highly efficient heat treatment of an article to be heated. This approach also permits the thickness of the overall device to be reduced. The supply of combustion air in the form of a swirling stream makes it possible to provide a high-velocity combustion burner without using a high-pressure fuel gas, with the advantage of satisfactory mixture of the fuel gas and combustion air and consequently markedly reduced combustion noise.

  8. Advances to improve the eating and cooking qualities of rice by marker-assisted breeding.

    Science.gov (United States)

    Phing Lau, Wendy Chui; Latif, Mohammad Abdul; Y Rafii, Mohd; Ismail, Mohd Razi; Puteh, Adam

    2016-01-01

    The eating and cooking qualities of rice are heavily emphasized in breeding programs because they determine market values and they are the appealing attributes sought by consumers. Conventional breeding has developed traditional varieties with improved eating and cooking qualities. Recently, intensive genetic studies have pinpointed the genes that control eating and cooking quality traits. Advances in genetic studies have developed molecular techniques, thereby allowing marker-assisted breeding (MAB) for improved eating and cooking qualities in rice. MAB has gained the attention of rice breeders for the advantages it can offer that conventional breeding cannot. There have been successful cases of using MAB to improve the eating and cooking qualities in rice over the years. Nevertheless, MAB should be applied cautiously given the intensive effort needed for genotyping. Perspectives from conventional breeding to marker-assisted breeding will be discussed in this review for the advancement of the eating and cooking qualities of fragrance, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT) in rice. These four parameters are associated with eating and cooking qualities in rice. The genetic basis of these four parameters is also included in this review. MAB is another approach to rice variety improvement and development in addition to being an alternative to genetic engineering. The MAB approach shortens the varietal development time, and is therefore able to deliver improved rice varieties to farmers within a shorter period of time.

  9. Advance in Researches on Toxicology of Brominated Flame Retardants%溴系阻燃剂的毒理学研究进展

    Institute of Scientific and Technical Information of China (English)

    杜苗苗; 张娴; 颜昌宙

    2012-01-01

    溴系阻燃剂(brominated flame retardants,BFRs)广泛应用于塑料、电子、建筑、纺织等材料和产品中,在多种环境介质中都可以检测到BFRs的存在.目前市场上的溴系阻燃剂主要有3种:四溴双酚A(tetrabromobisphenol A,TBBPA)、多溴联苯醚(polybrominated diphenyl ethers,PBDEs)和六溴环十二烷(hexabromocyclododecanes,HBCDs).近年来,进入环境中的BFRs在数量和种类上迅速增加,由此引发的环境效应日益受到国际社会广泛关注,有关BFRs的毒理学研究也成为相关领域的焦点内容.在总结近年来国内外相关研究的基础上,就BFRs在内分泌干扰效应、肝脏毒性、生殖毒性和神经毒性等方面的研究现状及需要进一步研究的内容进行了综述.

  10. Advances in energy and environment. Vol. 2: Air quality, water quality

    International Nuclear Information System (INIS)

    The 5th conference of energy and environment was held on 3-6 June 1996 in Cairo. The specialists discussed the effects of advances in energy and environment. The applications of solar energy, heat transfer, thermal application, storage and bio-conversion, fuels, energy and development. This second volume covers papers presented on the subjects air pollution, environmental protection, solid and hazardous wastes, water and wastewater treatment. tabs., figs

  11. Igniting the Paralympic Flame

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Deaf-mute Jiang Xintian lights a small cauldron in the hands of wheelchairbound fencer Jin Jing at the Paralympic Flame Lighting Ceremony in Beijing’s symbolic Temple of Heaven on August 28. For nine days until September 6, when the 13th Paralympics opens in Beijing, a total of 850 torchbearers would relay the Paralympic flame along two routes through 11 Chinese provinces,

  12. Recent Advances and Applications of Near Infrared Spectroscopy for Honey Quality Assessment

    Directory of Open Access Journals (Sweden)

    Guiyun Chen

    2014-04-01

    Full Text Available Currently, most of the technologies used to identify honey quality are inefficient and costly. There is a necessity to develop a more effective one for honey quality assessment. Near Infrared Spectroscopy (NIRS has the potential to be such a technique for its unique characteristics. This study reviews recent advances and applications of NIR spectroscopy in honey authentication domain including constituents, adulteration, brand, botanical origin and geographical origin. It presents a comprehensive using of this technology, with advantages and limitations, in honey quality detection, which offers insights on selecting the most appropriate NIR spectroscopic method for samples presentation, spectral acquisition, spectral pretreatment and modeling. Future research is to be focused on increasing model robustness, developing overall NIR spectroscopic database and a NIR-based integrated technology system on honey quality assessment.

  13. Water quality monitoring of Jialing-River in Chongqing using advanced ion chromatographic system

    Institute of Scientific and Technical Information of China (English)

    Kazuhiko TANAKA; Chao-Hong SHI; Nobukazu NAKAGOSHI

    2012-01-01

    The water quality monitoring operation to evaluate the water quality of polluted river is an extremely important task for the river-watershed management/control based on the environmental policy.In this study,the novel,simple and convenient water quality monitoring of Jialing-River in Chongqing,China was carried out using an advanced ion chromatography (IC) consisting of ion-exclusion/cation-exchange chromatography (IEC/CEC) with conductivity detection for determining simultaneously the common anions such as SO42 -,Cl -,and NO3- and the cations such as Na+,NH4+,K+,Mg2+,and Ca2+,the ion-exclusion chromatography (IEC) with visible detection for determining simultaneously the nutrient components such as phosphate and silicate ions,and the IEC with the enhanced conductivity detection using a post column of K+ -form cation-exchange resin for determining HCO3- -alkalinity as an inorganic-carbon source for biomass synthesis in biological reaction process under the aerobic conditions.According to the ionic balance theory between the total equivalent con-centrations of anions and cations,the water quality evaluation of the Jialing-River waters taking at different sampling sites in Chongqing metropolitan area was carried out using the advanced IC system.As a result,the effectiveness of this novel water quality monitoring methodology using the IC system was demonstrated on the several practical applications to a typical biological sewage treatment plant on Jialing-River of Chongqing.

  14. Improving the Data Quality of Advanced LIGO Based on Early Engineering Run Results

    CERN Document Server

    Nuttall, L K; Areeda, J; Betzwieser, J; Dwyer, S; Effler, A; Fisher, R P; Fritschel, P; Kissel, J S; Lundgren, A P; Macleod, D M; Martynov, D; McIver, J; Mullavey, A; Sigg, D; Smith, J R; Vajente, G; Williamson, A R; Wipf, C C

    2015-01-01

    The Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors have completed their initial upgrade phase and will enter the first observing run in late 2015, with detector sensitivity expected to improve in future runs. Through the combined efforts of on-site commissioners and the Detector Characterization group of the LIGO Scientific Collaboration, interferometer performance, in terms of data quality, at both LIGO observatories has vastly improved from the start of commissioning efforts to present. Advanced LIGO has already surpassed Enhanced LIGO in sensitivity, and the rate of noise transients, which would negatively impact astrophysical searches, has improved. Here we give details of some of the work which has taken place to better the quality of the LIGO data ahead of the first observing run.

  15. Multivariate data analysis as a tool in advanced quality monitoring in the food production chain

    DEFF Research Database (Denmark)

    Bro, R.; van den Berg, F.; Thybo, A.;

    2002-01-01

    This paper summarizes some recent advances in mathematical modeling of relevance in advanced quality monitoring in the food production chain. Using chemometrics-multivariate data analysis - it is illustrated how to tackle problems in food science more efficiently and, moreover, solve problems...... processing, and will cover areas such as analysis of variance, monitoring and handling of sampling variation, calibration, exploration/data mining and hard modeling. (C) 2002 Elsevier Science Ltd. All rights reserved....... that could not otherwise be handled before. The different mathematical models are all exemplified by food related subjects to underline the generic use of the models within the food chain. Applications will be given from meat, storage, vegetable characterization, fish quality monitoring and industrial food...

  16. Advanced wastewater treatment by nanofiltration and activated carbon for high quality water reuse

    OpenAIRE

    Kazner, Christian

    2012-01-01

    Hybrid processes combining activated carbon and nanofiltration have been studied to identify the optimum solution for advanced wastewater treatment in high quality water reclamation and reuse. With a focus on the removal of bulk and trace organic compounds the investigation identified three promising process combinations, namely powdered activated carbon followed by nanofiltration (PAC/NF), granular activated carbon followed by nanofiltration (GAC/NF) and nanofiltration followed by granular a...

  17. Quality of life among advanced breast cancer patients with and without distant metastasis

    OpenAIRE

    Wyatt, G.; Sikorskii, A.; TAMKUS, D.; You, M

    2012-01-01

    This study presents the results of a secondary analysis of data collected during a trial of reflexology that aimed to improve health-related quality of life (HRQOL) among women with advanced breast cancer in treatment. A comparison of HRQOL (functioning, symptoms, spirituality) of those with (n = 298) and without (n = 87) distant metastasis is presented. Following the intake interview, 385 women were randomised to reflexology, lay foot manipulation or conventional care control, and were inter...

  18. Quality assurance issues in conducting multi-institutional advanced technology clinical trials.

    Science.gov (United States)

    Purdy, James A

    2008-01-01

    The National Cancer Institute-sponsored Advanced Technology Quality Assurance (QA) Consortium, which consisted of the Image-Guided Therapy QA Center, Radiation Therapy Oncology Group, Radiological Physics Center, Quality Assurance Review Center, and Resource Center for Emerging Technologies, has pioneered the development of an infrastructure and QA method for advanced technology clinical trials that requires volumetric digital data submission of a protocol patient's treatment plan and verification data. In particular, the Image-Guided Therapy QA Center has nearly 15 years experience in facilitating QA review for Radiation Therapy Oncology Group advanced technology clinical trials. This QA process includes (1) a data integrity review for completeness of protocol required elements, the format of data, and possible data corruption, and recalculation of dose-volume histograms; (2) a review of compliance with target volume and organ-at-risk contours by study chairs; and (3) a review of dose prescription and dose heterogeneity compliance by the Radiation Therapy Oncology Group Headquarters Dosimetry Group or the Radiological Physics Center dosimetrists (for brachytherapy protocols). This report reviews the lessons learned and the QA challenges presented by the use of advanced treatment modalities in clinical trials requiring volumetric digital data submission. PMID:18406941

  19. Chemical quality and temperature of water in Flaming Gorge Reservoir, Wyoming and Utah, and the effect of the reservoir on the Green River

    Science.gov (United States)

    Bolke, E.L.; Waddell, Kidd M.

    1975-01-01

    The major tributaries to Flaming Gorge Reservoir contribute an average of about 97 percent of the total streamflow and 82 percent of the total load of dissolved solids. The Green River is the largest tributary, and for the 1957-72 water years it contributed 81 percent of the total streamflow and 70 percent of the total load of dissolved solids. The principal constituents in the tributary streamflow are calcium and sulfate during periods of lowest flow and calcium and bicarbonate during periods of highest flow. Flaming Gorge Dam was closed in November 1962, and the most significant load changes of chemical constituents due to the net effect of inflow, outflow, leaching, and chemical precipitation in the reservoir have been load changes of sulfate and bicarbonate. The average increase of dissolved load of sulfate in the reservoir for the 1969-72 water years was 110,000 tons (99,790 t) per year, which was 40,000 tons (36,287 t) per year less than for the 1963-66 water years. The average decrease of dissolved load of bicarbonate in the reservoir for 1969-72 was 40,000 tons (36,287 t) per year, which was the same as the decrease for 1963-66. Anaerobic conditions were observed in the deep, uncirculated part of the reservoir near the dam during the 1971 and 1972 water years, and anaerobic or near-anaerobic conditions were observed near the confluence of the Blacks Fork and Green River during the summers of 1971 and 1972. The water in Flaming Gorge Reservoir is in three distinct layers, and the upper two layers (the epilimnion and the metalimnion) mixed twice during each of the 1971-72 water years. The two circulation periods were in the spring and fall. The water in the deepest layer (the hypolimnion) did not mix with the waters of the upper zones because the density difference was too great and because the deep, narrow shape of the basin probably inhibits mixing. The depletion of flow in the Green River downstream from Flaming Gorge Dam between closure of the dam and the

  20. Sandia National Laboratories Advanced Simulation and Computing (ASC) software quality plan. Part 1: ASC software quality engineering practices, Version 2.0.

    Energy Technology Data Exchange (ETDEWEB)

    Sturtevant, Judith E.; Heaphy, Robert; Hodges, Ann Louise; Boucheron, Edward A.; Drake, Richard Roy; Minana, Molly A.; Hackney, Patricia; Forsythe, Christi A.; Schofield, Joseph Richard, Jr. (,; .); Pavlakos, Constantine James; Williamson, Charles Michael; Edwards, Harold Carter

    2006-09-01

    The purpose of the Sandia National Laboratories Advanced Simulation and Computing (ASC) Software Quality Plan is to clearly identify the practices that are the basis for continually improving the quality of ASC software products. The plan defines the ASC program software quality practices and provides mappings of these practices to Sandia Corporate Requirements CPR 1.3.2 and 1.3.6 and to a Department of Energy document, ASCI Software Quality Engineering: Goals, Principles, and Guidelines. This document also identifies ASC management and software project teams responsibilities in implementing the software quality practices and in assessing progress towards achieving their software quality goals.

  1. Sandia National Laboratories Advanced Simulation and Computing (ASC) Software Quality Plan. Part 2, Mappings for the ASC software quality engineering practices. Version 1.0.

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Molly A.; Heaphy, Robert; Sturtevant, Judith E.; Hodges, Ann Louise; Boucheron, Edward A.; Drake, Richard Roy; Forsythe, Christi A.; Schofield, Joseph Richard, Jr.; Pavlakos, Constantine James; Williamson, Charles Michael; Edwards, Harold Carter

    2005-01-01

    The purpose of the Sandia National Laboratories Advanced Simulation and Computing (ASC) Software Quality Plan is to clearly identify the practices that are the basis for continually improving the quality of ASC software products. The plan defines the ASC program software quality practices and provides mappings of these practices to Sandia Corporate Requirements CPR 1.3.2 and 1.3.6 and to a Department of Energy document, 'ASCI Software Quality Engineering: Goals, Principles, and Guidelines'. This document also identifies ASC management and software project teams responsibilities in implementing the software quality practices and in assessing progress towards achieving their software quality goals.

  2. Motion-base simulator results of advanced supersonic transport handling qualities with active controls

    Science.gov (United States)

    Feather, J. B.; Joshi, D. S.

    1981-01-01

    Handling qualities of the unaugmented advanced supersonic transport (AST) are deficient in the low-speed, landing approach regime. Consequently, improvement in handling with active control augmentation systems has been achieved using implicit model-following techniques. Extensive fixed-based simulator evaluations were used to validate these systems prior to tests with full motion and visual capabilities on a six-axis motion-base simulator (MBS). These tests compared the handling qualities of the unaugmented AST with several augmented configurations to ascertain the effectiveness of these systems. Cooper-Harper ratings, tracking errors, and control activity data from the MBS tests have been analyzed statistically. The results show the fully augmented AST handling qualities have been improved to an acceptable level.

  3. Evaluation of Water Quality Renovation by Advanced Soil-Based Wastewater Treatment Systems

    Science.gov (United States)

    Cooper, J.; Loomis, G.; Kalen, D.; Boving, T.; Morales, I.; DeLuca, J.; Amador, J.

    2013-12-01

    25% of US households utilize onsite wastewater treatment systems (OWTS) for wastewater management. Advanced technologies were designed to overcome the inadequate wastewater treatment by conventional OWTS in critical shallow water table areas, such as coastal zones, in order to protect ground water quality. In addition to the septic tank and soil drainfield that comprise a conventional OWTS, advanced systems claim improved water renovation with the addition of sand filtration, timed dosing controls, and shallow placement of the infiltrative zone. We determined water quality renovation functions under current water table and temperature conditions, in anticipation of an experiment to measure OWTS response to a climate change scenario of 30-cm increase in water table elevation and 4C temperature increase. Replicate (n=3) intact soil mesocosms were used to evaluate the effectiveness of drainfields with a conventional wastewater delivery (pipe-and-stone) compared to two types of pressurized, shallow narrow drainfield. Results under steady state conditions indicate complete removal of fecal coliform bacteria, phosphorus and BOD by all soil-based systems. By contrast, removal of total nitrogen inputs was 16% in conventional and 11% for both advanced drainfields. Effluent waters maintained a steady state pH between 3.2 - 3.7 for all technologies. Average DO readings were 2.9mg/L for conventional drainfield effluent and 4.6mg/L for advanced, showing the expected oxygen uptake with shallow placement of the infiltrative zone. The conventional OWTS is outperforming the advanced with respect to nitrogen removal, but renovating wastewater equivalently for all other contaminants of concern. The results of this study are expected to facilitate development of future OWTS regulation and planning guidelines, particularly in coastal zones and in the face of a changing climate.

  4. Flaming on YouTube

    NARCIS (Netherlands)

    Moor, Peter J.; Heuvelman, Ard; Verleur, Ria

    2010-01-01

    In this explorative study, flaming on YouTube was studied using surveys of YouTube users. Flaming is defined as displaying hostility by insulting, swearing or using otherwise offensive language. Three general conclusions were drawn. First, although many users said that they themselves do not flame,

  5. FLAME OF GLORY

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The Olympic torch relay will spread peace and harmony across the world Two old nations,one shared dream.A symbolic integration of Eastern and Western civi- lizations was realized when a dramatically dressed Greek priestess kindled a specially designed torch for the Beijing Olympics at the ancient stadium in Olympia,Greece.In a flawless ceremony amid sunrays on March 24,High Priestess Maria Nafpliotou lit the Olympic flame with a concave mirror in front of the Hera Temple in Olympia.The flame was then held in a replica of an ancient urn to ignite the first torch for the upcoming Summer Games in

  6. Quality of life among advanced breast cancer patients with and without distant metastasis.

    Science.gov (United States)

    Wyatt, G; Sikorskii, A; Tamkus, D; You, M

    2013-03-01

    This study presents the results of a secondary analysis of data collected during a trial of reflexology that aimed to improve health-related quality of life (HRQOL) among women with advanced breast cancer in treatment. A comparison of HRQOL (functioning, symptoms, spirituality) of those with (n = 298) and without (n = 87) distant metastasis is presented. Following the intake interview, 385 women were randomised to reflexology, lay foot manipulation or conventional care control, and were interviewed again at weeks 5 and 11. Those with distant metastasis were older, had fewer comorbid conditions, and a smaller proportion were employed. Longitudinal analysis of HRQOL at intake, 5 and 11 weeks revealed that those with distant metastasis had lower functioning and more pain; however, no differences were found on fatigue, nausea, shortness of breath, sleep quality, anxiety, depressive symptoms or spirituality. Despite advanced disease, 56% of all women in this study were below the clinical screening cut-off for depressive symptoms. These findings may indicate that patients with advanced breast cancer have adapted emotionally and spiritually; however, the management of physical symptoms remains a priority. PMID:23252474

  7. Flame Stretch Analysis in Diffusion Flames with Inert Gas

    Institute of Scientific and Technical Information of China (English)

    Ay Su; Ying-Chieh Liu

    2001-01-01

    Experimental investigations of impinging flame with fuel mixed with non-reaction gas were conducted.According to the observations of combustion test and temperature measurement, the non-reaction gas might dilute the local concentration of fuel in the diffusion process. The shape of the flame was symmetrical due to the flame stretch force. Results show that the conical flame might be de-structured by the addition of inert gas in pure methane fuel. The impinging flame became shorter and bluer as nitrogen was added to the fuel. The conditions of N2/CH4 equal to 1/2 and 1/1 show a wider plane in the YZ plane. The effect of inert gas overcomes the flame stretch and destroys the symmetrical column flame as well as the cold flow. Nitrogen addition also enhances the diffusion rate and combustion efficiency.

  8. Palliative home care intervention to improve the quality of life of women with advanced breast cancer

    International Nuclear Information System (INIS)

    The quality of life is affected frequently observed in women with advanced breast cancer and is considered a leading indicator of effectiveness of palliative care. A descriptive, quasi-experimental study is presented ex-ante / ex-post, by applying open-ended interviews to explore the effects on the processes of adaptation of each patient and a self-administrable scale identified specific dimensions of quality of life, satisfaction with care and overall quality of life. The intervention was performed palliative home care to 52 women, according to the damages identified in the baseline diagnosis. The overall strategy included four steps: clinical and socio-demographic characterization of women; identification of the effects on the processes of adaptation by the theoretical model of Roy and dimensions of quality of life frequently affected, to design individually oriented actions on the drive shaft of Nursing Interventions Classification and evaluation of results intervention. The dimensions achieved higher frequency of involvement were: behavior, physical symptoms, pain interference and leisure activities, social life and family. Data were analyzed with qualitative methodologies and uni and multivariate statistical processing. After the intervention favorable changes in adaptive processes and dimensions of quality of life were observed; well as in the assessment of overall satisfaction with life. It was interesting that the dimensions of satisfaction assessed at the end of the intervention obtained an unfavorable assessment, outcome associated with sociodemographic variables. (author)

  9. [The quality of life after chemotherapy in advanced non-small cell lung cancer patients].

    Science.gov (United States)

    Słowik-Gabryelska, A; Szczepanik, A; Kalicka, A

    1999-01-01

    The intensity of complains, short survival and great number of patients makes many oncologists to apply chemotherapy in advanced non-small cell lung cancer/NSCLC/. The achieved median duration of life after chemotherapy was 6 to 12 month. From the other hand non small cell lung cancer chemotherapy is a big burden even to healthy persons. It can worsen the quality of life. That was the reason we evaluated the quality of life after chemotherapy in advanced non small cell lung cancer patients. Taking into account, that the evaluation of quality of life, used in most diseases is useless in advanced NSCLC patients, for appreciation the quality of life in these cases the lung cancer symptoms scale/LCSS/was adopted. In 110 non small cell lung cancer patients in stage IIIB and IV, who received combined chemotherapy by Le Chevalier/Vindesine, Cisplatin, Cyclophosphamide, Lomustin/or by Rosell/Mitomycin, Cyclophosphamide, Cisplatin/the quality of life was evaluated. In 20-persons control group all patients received the symptomatic treatment. In observed group of 110 patients, tumor regressions after 4 courses of chemotherapy allowed to resect cancer in 14 cases, to apply radiotherapy in 42 and to continue chemiotherapy in 23 persons. In every person from above mentioned group the quality of life was evaluated on the basis of intensity of cancer symptoms, accordingly to LCSS. The intensity of cancer symptoms was compared before and after treatment. There were compared; the innensity of complains, weakness, appetite, malnutrition, and hematological, neurological, performans state as well as respiratory sufficiency, infections, cardiac disorders and pain. Apart it, the side effects of applied therapy were assessed in 5 degree scale. The level of hemoglobin, the number of leucocytes, thrombocytes, bilirubine and transaminases in peripheral blood, hematurie, proteinurie, bleedings, appetite, nausea, vomitings, diarrhea, mucosal lesions, infections, skin lesions, cardiac lesions

  10. Modeling turbulent flame propagation

    Energy Technology Data Exchange (ETDEWEB)

    Ashurst, W.T.

    1994-08-01

    Laser diagnostics and flow simulation techniques axe now providing information that if available fifty years ago, would have allowed Damkoehler to show how turbulence generates flame area. In the absence of this information, many turbulent flame speed models have been created, most based on Kolmogorov concepts which ignore the turbulence vortical structure, Over the last twenty years, the vorticity structure in mixing layers and jets has been shown to determine the entrainment and mixing behavior and these effects need to be duplicated by combustion models. Turbulence simulations reveal the intense vorticity structure as filaments and simulations of passive flamelet propagation show how this vorticity Creates flame area and defines the shape of the expected chemical reaction surface. Understanding how volume expansion interacts with flow structure should improve experimental methods for determining turbulent flame speed. Since the last decade has given us such powerful new tools to create and see turbulent combustion microscopic behavior, it seems that a solution of turbulent combustion within the next decade would not be surprising in the hindsight of 2004.

  11. Flame retardant tarpaulin

    Energy Technology Data Exchange (ETDEWEB)

    Nozaki, Saiji; Takahashi, Yutaka; Uehara, Hiroshi

    1998-07-28

    A flame retardant tarpaulin is used for protecting equipments upon periodical repairing in places for handling radioactive materials such as a nuclear power plant. It is formed by coating a woven fabric, a knitted fabric or a non-woven fabric with from 100 to 1000% by weight of a composition formed by blending from 3 to 10 parts by weight of red phosphorus and from 7 to 25 parts by weight of melamine sulfate to 100 parts by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of from 8 to 28% by weight. Further, it comprises metal hydroxides such as Mg hydroxide and Al hydroxide. Aids such as plasticizers, stabilizers, lubricants and colorants can optionally be blended so long as they do not inhibit the flame retardant effect. It has an excellent flame retardancy, and does not produce poisonous gases or a great amount of ashes when burnt and discarded. It can be processed with satisfactory dimensional accuracy upon cutting and stitching, and has flame-proofness as specified by the fire laws. (T.M.)

  12. ERCC1, toxicity and quality of life in advanced NSCLC patients randomized in a large multicentre phase III trial

    DEFF Research Database (Denmark)

    Vilmar, Adam Christian; Santoni-Rugiu, Eric; Sørensen, Jens Benn

    2010-01-01

    Excision repair cross complementation group 1 (ERCC1) is a promising biomarker in advanced non-small cell lung cancer (NSCLC). However, current evidence regarding the impact of ERCC1 on toxicity and quality of life (QOL) is limited.......Excision repair cross complementation group 1 (ERCC1) is a promising biomarker in advanced non-small cell lung cancer (NSCLC). However, current evidence regarding the impact of ERCC1 on toxicity and quality of life (QOL) is limited....

  13. Goals of care in advanced dementia: quality of life, dignity and comfort.

    Science.gov (United States)

    Volicer, L

    2007-01-01

    Prolongation of human lifespan is increasing the number of individuals suffering from Alzheimer's disease and other progressive dementia worldwide. There are about 5 million of these individuals in both United States and European Union and many more in other countries of the world (1). Because there is no curative treatment for these diseases, most individuals with dementia survive to an advanced stage of dementia at which time many of them require institutional care. Home care for individuals with advanced dementia and especially institutional care are very expensive and are becoming major public health problems. The cost of care for advanced dementia is often increased by the use of aggressive medical interventions that may not be in the best interest of the patient. Because advanced dementia is currently incurable, it should be considered a terminal illness, similar to terminal cancer. Therefore, palliative care may be the most appropriate strategy for management of advanced dementia (2). The goals of palliative care are maintenance of quality of life, dignity and comfort and the four articles in this special issue are addressing these goals. Enhancement of quality of life in dementia requires attention to three main domains: provision of meaningful activities, appropriate medical care, and treatment of behavioral symptoms (3). Individuals with advanced dementia may not be able to participate in many activity programs but they still may maintain some quality of life if they are provided care in a pleasant environment with constant presence of a caregiver. Simard describes a program, Namaste Care, which is specifically tailored for individuals with advanced dementia. This program requires neither major expenditure nor increased staffing and should be instituted in all facilities that care for individuals with advanced dementia. Maintaining functional status of individuals with advanced dementia is important because it improves their self esteem and facilitates

  14. Turbulent oxygen flames in type Ia supernovae

    OpenAIRE

    Aspden, Andrew; Bell, J.; Woosley, S.

    2011-01-01

    In previous studies, we examined turbulence-flame interactions in carbon-burning thermonuclear flames in Type Ia supernovae. In this study, we consider turbulence-flame interactions in the trailing oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the oxygen flame. Scaling arguments analogous to the carbon flames are presented and then compared agains...

  15. Advanced river water quality monitoring stations at the Moravica river in Serbia

    Directory of Open Access Journals (Sweden)

    Đorđević Đ.

    2006-01-01

    Full Text Available The overall objective of this project is the immediate enhancement of the water quality management in Serbia as an example of excellence for the South East Balkan region. Therefore, close links between the local and regional economy and the Serbian Higher Education sector will be created through technology and knowledge transfer. New technologies like GPRS Technology to realize data transfer from distance hydro measure stations will be introduced in the water quality monitoring management. Outcomes of the project are a measurement program for Advanced River Water Quality Monitoring, a pilot station and operator staff for the realization of the monitoring scheme devices including GPRS-Technology for the monitoring scheme, a monitoring station to conduct a test run, a quality management scheme, training measures for operators of monitoring stations, analyzed data from measurement program and dissemination and networking measures like a final international conference. The project is funded within the scope of the Tempus Program (Tempus Cards Structural and Complementary Projects of the EU.

  16. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of organophosphate pesticides in filtered water by gas chromatography with flame photometric detection

    Science.gov (United States)

    Jha, Virendra K.; Wydoski, Duane S.

    2002-01-01

    A method for the isolation of 20 parent organophosphate pesticides and 5 pesticide degradates from filtered natural-water samples is described. Seven of these compounds are reported permanently with an estimated concentration because of performance issues. Water samples are filtered to remove suspended particulate matter, and then 1 liter of filtrate is pumped through disposable solid-phase extraction columns that contain octadecyl-bonded porous silica to extract the compounds. The C-18 columns are dried with nitrogen gas, and method compounds are eluted from the columns with ethyl acetate. The extract is analyzed by dual capillary-column gas chromatography with flame photometric detection. Single-operator method detection limits in all three water-matrix samples ranged from 0.004 to 0.012 microgram per liter. Method performance was validated by spiking all compounds into three different matrices at three different concentrations. Eight replicates were analyzed at each concentration level in each matrix. Mean recoveries of method compounds spiked in surface-water samples ranged from 39 to 149 percent and those in ground-water samples ranged from 40 to 124 percent for all pesticides except dimethoate. Mean recoveries of method compounds spiked in reagent-water samples ranged from 41 to 119 percent for all pesticides except dimethoate. Dimethoate exhibited reduced recoveries (mean of 43 percent in low- and medium-concentration level spiked samples and 20 percent in high-concentration level spiked samples) in all matrices because of incomplete collection on the C-18 column. As a result, concen-trations of dimethoate and six other compounds (based on performance issues) in samples are reported in this method with an estimated remark code.

  17. Health-related quality of life among patients with advanced cancer: an integrative review

    Directory of Open Access Journals (Sweden)

    Maria Eliane Moreira Freire

    2014-04-01

    Full Text Available This integrative literature review aimed to characterize scientific articles on health-related quality of life – HRQoL – among patients with advanced cancer from national and international literature, and summarize those factors evidenced in the literature that contributed to the improvement or worsening of HRQoL among patients with advanced cancer. The search for materials was conducted in the following databases: CINAHL, EMBASE, PubMed, SciELO and LILACS. Among the 21 articles in the sample, 13 showed an improvement of HRQoL among patients with advanced cancer related to the development of physical, emotional and spiritual interventions. In eight studies, we identified predictive symptoms of low HRQoL, such as pain, fatigue, sleep disorders, depression, nutritional changes, and others. The results showed that clinical manifestations, which many times were inherent in cancer, such as factors that can lower patients’ HRQoL, while physical, psychological and spiritual benefits resulting from therapeutic interventions may promote its improvement.

  18. Recent Developments in Halogen Free Flame Retardants for Epoxy Resins for Electrical and Electronic Applications

    Directory of Open Access Journals (Sweden)

    Manfred Döring

    2010-08-01

    Full Text Available The recent implementation of new environmental legislations led to a change in the manufacturing of composites that has repercussions on printed wiring boards (PWB. This in turn led to alternate processing methods (e.g., lead-free soldering, which affected the required physical and chemical properties of the additives used to impart flame retardancy. This review will discuss the latest advancements in phosphorus containing flame retardants for electrical and electronic (EE applications and compare them with commercially available ones. The mechanism of degradation and flame retardancy of phosphorus flame retardants in epoxy resins will also be discussed.

  19. Evaluation of water quality functions of conventional and advanced soil-based onsite wastewater treatment systems.

    Science.gov (United States)

    Cooper, Jennifer A; Loomis, George W; Kalen, David V; Amador, Jose A

    2015-05-01

    Shallow narrow drainfields are assumed to provide better wastewater renovation than conventional drainfields and are used for protection of surface and ground water. To test this assumption, we evaluated the water quality functions of two advanced onsite wastewater treatment system (OWTS) drainfields-shallow narrow (SND) and Geomat (GEO)-and a conventional pipe and stone (P&S) drainfield over 12 mo using replicated ( = 3) intact soil mesocosms. The SND and GEO mesocosms received effluent from a single-pass sand filter, whereas the P&S received septic tank effluent. Between 97.1 and 100% of 5-d biochemical oxygen demand (BOD), fecal coliform bacteria, and total phosphorus (P) were removed in all drainfield types. Total nitrogen (N) removal averaged 12.0% for P&S, 4.8% for SND, and 5.4% for GEO. A mass balance analysis accounted for 95.1% (SND), 94.1% (GEO), and 87.6% (P&S) of N inputs. When the whole treatment train (excluding the septic tank) is considered, advanced systems, including sand filter pretreatment and SND or GEO soil-based treatment, removed 99.8 to 99.9% of BOD, 100% of fecal coliform bacteria and P, and 26.0 to 27.0% of N. In contrast, the conventional system removed 99.4% of BOD and 100% of fecal coliform bacteria and P but only 12.0% of N. All drainfield types performed similarly for most water quality functions despite differences in placement within the soil profile. However, inclusion of the pretreatment step in advanced system treatment trains results in better N removal than in conventional treatment systems despite higher drainfield N removal rates in the latter.

  20. Spirituality, distress, depression, anxiety, and quality of life in patients with advanced cancer

    Directory of Open Access Journals (Sweden)

    A Kandasamy

    2011-01-01

    Full Text Available Objective: To study the influence of spiritual well being (Sp WB on symptoms of distress, depression, and other dimensions of quality of life in advanced cancer patients receiving palliative care. Materials and Methods: The study was cross-sectional in nature. Fifty patients with advanced cancer from a hospice were assessed with the following instruments: the visual analog scale for pain (VAP, M.D. Anderson symptom inventory (MDASI, Hospital Anxiety Depression Scale (HADS, Functional assessment of cancer therapy - Palliative Care (FACT-pal, and Functional assessment of chronic illness therapy-spiritual well-being (FACIT-sp. We studied the correlations between spirituality and other variables on these scales. Results: Depression and anxiety were negatively correlated with spiritual well-being (Sp WB. Sp WB was significantly correlated with fatigue (r = -0.423, P = 0.002, symptom distress (r = -0.717, P < 0.001, memory disturbance (r = -0.520, P < 0.001, loss of appetite (r = -0.399, P = 0.004, drowsiness (r = -0.400, P = 0.004, dry mouth (r = -0.381, P = 0.006, and sadness (r = -0.720, P < 0.001. Sp WB was positively correlated with all the other aspects of QOL measures. Predictors such as palliative care well-being (t = 2.840, P = 0.008, distress (t = -2.582, P = 0.015, sadness (t = -2.765, P = 0.010, mood (t = 2.440, P = 0.021, and enjoyment in life (t = -3.586, P = 0.001 were significantly correlated with Sp WB, after regression analysis. Conclusions: This study suggests that spiritual well being is an important component of the quality of life of advanced cancer patients, and is closely related to the physical and psychological symptoms of distress. It should be addressed appropriately and adequately in palliative care settings.

  1. [Advanced nursing practice: a must for the quality of care and mental health services].

    Science.gov (United States)

    Ricard, Nicole; Page, Claire; Laflamme, France

    2014-01-01

    New professional legislation and reorganization of mental health services have had a significant influence on mental health nursing practice. Many nurses have demonstrated clinical leadership and have been able to adapt their services to the needs of the population specially in the primary health care setting. However, many believe that the role of nurses is not sufficiently known and optimally utilized in mental health services. In this article we take a critical look at the mental health nursing practice in Quebec and at the essential requirements for its development. This review aims to: 1) describe current trends in the changing roles and the modernization of mental health nursing practice in Quebec, 2) provide an overview of the development of advanced nursing practice and its impact on the quality of mental health services; 3) clarify the concept of advanced nursing practice and position its development in Quebec and 4) propose various strategies for optimizing the role of nurses and their complementarity with other professionals providing mental health services. This review presents innovative practices developed by nurses in the context of the restructuring of mental health services. For example, new nursing roles have been developed to improve the collaboration with general practitioners groups in primary care settings and facilitate the evaluation and monitoring of patient presenting medical and psychological problems. Another interesting innovation was set up by nurses in developing a new service to allow timely access to integrated care for patients with substance abuse and mental health problems. The various testimonies reported in this article illustrate the potential contribution of these nursing innovations in improving the mental health services in Quebec. Also, in few countries, the reform of mental health services has been a good time to recognize this potential. Thus, some countries have repositioned the role of mental health nurses and

  2. [Advanced nursing practice: a must for the quality of care and mental health services].

    Science.gov (United States)

    Ricard, Nicole; Page, Claire; Laflamme, France

    2014-01-01

    New professional legislation and reorganization of mental health services have had a significant influence on mental health nursing practice. Many nurses have demonstrated clinical leadership and have been able to adapt their services to the needs of the population specially in the primary health care setting. However, many believe that the role of nurses is not sufficiently known and optimally utilized in mental health services. In this article we take a critical look at the mental health nursing practice in Quebec and at the essential requirements for its development. This review aims to: 1) describe current trends in the changing roles and the modernization of mental health nursing practice in Quebec, 2) provide an overview of the development of advanced nursing practice and its impact on the quality of mental health services; 3) clarify the concept of advanced nursing practice and position its development in Quebec and 4) propose various strategies for optimizing the role of nurses and their complementarity with other professionals providing mental health services. This review presents innovative practices developed by nurses in the context of the restructuring of mental health services. For example, new nursing roles have been developed to improve the collaboration with general practitioners groups in primary care settings and facilitate the evaluation and monitoring of patient presenting medical and psychological problems. Another interesting innovation was set up by nurses in developing a new service to allow timely access to integrated care for patients with substance abuse and mental health problems. The various testimonies reported in this article illustrate the potential contribution of these nursing innovations in improving the mental health services in Quebec. Also, in few countries, the reform of mental health services has been a good time to recognize this potential. Thus, some countries have repositioned the role of mental health nurses and

  3. Turbulent Flame Propagation Characteristics of High Hydrogen Content Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Seitzman, Jerry [Georgia Inst. of Technology, Atlanta, GA (United States); Lieuwen, Timothy [Georgia Inst. of Technology, Atlanta, GA (United States)

    2014-09-30

    This final report describes the results of an effort to better understand turbulent flame propagation, especially at conditions relevant to gas turbines employing fuels with syngas or hydrogen mixtures. Turbulent flame speeds were measured for a variety of hydrogen/carbon monoxide (H2/CO) and hydrogen/methane (H2/CH4) fuel mixtures with air as the oxidizer. The measurements include global consumption speeds (ST,GC) acquired in a turbulent jet flame at pressures of 1-10 atm and local displacement speeds (ST,LD) acquired in a low-swirl burner at atmospheric pressure. The results verify the importance of fuel composition in determining turbulent flame speeds. For example, different fuel-air mixtures having the same unstretched laminar flame speed (SL,0) but different fuel compositions resulted in significantly different ST,GC for the same turbulence levels (u'). This demonstrates the weakness of turbulent flame speed correlations based simply on u'/SL,0. The results were analyzed using a steady-steady leading points concept to explain the sensitivity of turbulent burning rates to fuel (and oxidizer) composition. Leading point theories suggest that the premixed turbulent flame speed is controlled by the flame front characteristics at the flame brush leading edge, or, in other words, by the flamelets that advance farthest into the unburned mixture (the so-called leading points). For negative Markstein length mixtures, this is assumed to be close to the maximum stretched laminar flame speed (SL,max) for the given fuel-oxidizer mixture. For the ST,GC measurements, the data at a given pressure were well-correlated with an SL,max scaling. However the variation with pressure was not captured, which may be due to non-quasi-steady effects that are not included in the current model. For the ST,LD data, the leading points model again faithfully captured the variation of turbulent flame speed over a wide range of fuel-compositions and turbulence intensities. These

  4. Photonic flame effect

    OpenAIRE

    Tcherniega, N. V.; Kudryavtseva, A. D.

    2006-01-01

    We observed new effect which we called photonic flame effect (PFE). Several 3-dimensional photonic crystals (artificial opals) were posed on Cu plate at the temperature of liquid nitrogen (77K). Typical distance between them was 1-5 centimeters. Long-continued optical luminescence was excited in one of them by the ruby laser pulse. Analogous visible luminescence manifesting time delay appeared in other samples of the crystals. Experiments were realized for opal crystals and for nanocomposites...

  5. Flame image monitoring and analysis in combustion management

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, D. [CEZ, a.s. Elektrarna Detmarovice, Detmarovice (Czech Republic); Huttunen, A.J.; Nihtinen, J.J. [Imatran Voima Oy, IVO Technology Centre, Vantaa (Finland)

    1997-12-31

    When NO{sub x} emissions are reduced with new low-NO{sub x} burners and infurnace modifications in old pulverised fuel boilers, many changes in the firing conditions may occur. Depending on coal quality and the original furnace design, low-NO{sub x} burners, overtire air, low-excess-air firing and other primary modifications in various combinations may cause flame instability, increased slagging, increased minimum load and other difficulties in controlling the burning process. To find and solve these problems quicker, a new type of burner management system for pulverised fuel and oil-fired boilers was developed by Imatran Voima Oy. The DIMAC combustion management system monitors and analyses individually each burner or burner level. There are special software for wall and corner fired boilers. The DIMAC system is comprised of two functional subsystems: flame monitoring and flame analysis. The DIMAC enables the power plant operators to minimise NO{sub x} emissions and optimise the burning efficiency with varying coal qualities and boiler loads at the same time so that slagging, unburnt carbon in fly ash and flame stability stay in acceptable limits. It also guarantees that burners operate in good safety conditions in each burner level. The DIMAC system monitors perpendicularly each individual burner and evaluates flame parameters. Real-time flame monitoring and analysis allows the operator to directly see the effect of changing fuel distribution on flame pattern and flame stability. Based on data from the DIMAC references the system can improve boiler efficiency by 0.2 - 0.5 per cent unit as a result of more efficient control of the burning process. At the same time, the NO{sub x} formation can be reduced by 10 - 20 % 2 refs.

  6. Effects of advanced wastewater treatment on the quality of White River, Indiana

    Science.gov (United States)

    Crawford, Charles G.; Wangsness, David J.

    1991-01-01

    In 1983, the City of Indianapolis, Indiana, completed construction of advanced wastewater treatment (AWT) systems to enlarge and upgrade its existing Belmont Road and Southport Road secondary treatment plants. A nonparametric statistical procedure, a modified form of the Wilcoxon-Mann-Whitney rank-sum test, was used to test for trends in water quality at two upstream and two downstream sites on White River and at the two treatment plants. Results comparing the pre- (1978-1980) and post- (1983-1988) AWT periods show statistically significant improvements in the quality of the treated effluent and of the White River downstream from the plants. Water quality at sites upstream from the city was relatively constant during the period of study. Total ammonia (as N) decreased 14.6 mg/L and BOD5 (five-day biochemical oxygen demand) decreased 10 to 19 mg/L in the two effluents. Total ammonia in the river downstream from the plants decreased 0.8 to 1.9 mg/L and BOD5 decreased 2.3 to 2.5 mg/L. Nitrate (as N) increased 14.5 mg/L in the plant effluents and 2.0 to 2.4 mg/L in the river because of in-plant nitrification. Dissolved oxygen concentration in the river increased about 3 mg/L because of reduced oxygen demand for nitrification and biochemical oxidation processes.

  7. Recent advances in rapid and non-destructive assessment of meat quality using hyperspectral imaging

    Science.gov (United States)

    Tao, Feifei; Ngadi, Michael

    2016-05-01

    Meat is an important food item in human diet. Its production and consumption has greatly increased in the last decades with the development of economies and improvement of peoples' living standards. However, most of the traditional methods for evaluation of meat quality are time-consuming, laborious, inconsistent and destructive to samples, which make them not appropriate for a fast-paced production and processing environment. Development of innovative and non-destructive optical sensing techniques to facilitate simple, fast, and accurate evaluation of quality are attracting increasing attention in the food industry. Hyperspectral imaging is one of the promising techniques. It integrates the combined merits of imaging and spectroscopic techniques. This paper provides a comprehensive review on recent advances in evaluation of the important quality attributes of meat including color, marbling, tenderness, pH, water holding capacity, and also chemical composition attributes such as moisture content, protein content and fat content in pork, beef and lamb. In addition, the future potential applications and trends of hyperspectral imaging are also discussed in this paper.

  8. Dynamics of unconfined spherical flames

    CERN Document Server

    Leblanc, Louis; Dennis, Kadeem; Zhe,; Liang,; Radulescu, Matei I

    2012-01-01

    Using the soap bubble technique, we visualize the dynamics of unconfined hydrogen-air flames using high speed schlieren video. We show that for sufficiently weak mixtures, i.e., low flame speeds, buoyancy effects become important. Flame balls of a critical dimension begin to rise. The experiments are found in very good agreement with the scaling laws proposed by Zingale and Dursi. We report the results in a fluid dynamics video.

  9. Quality assurance and risk management: Perspectives on Human Factors Certification of Advanced Aviation Systems

    Science.gov (United States)

    Taylor, Robert M.; Macleod, Iain S.

    1994-01-01

    This paper is based on the experience of engineering psychologists advising the U.K. Ministry of Defense (MoD) on the procurement of advanced aviation systems that conform to good human engineering (HE) practice. Traditional approaches to HE in systems procurement focus on the physical nature of the human-machine interface. Advanced aviation systems present increasingly complex design requirements for human functional integration, information processing, and cognitive task performance effectiveness. These developing requirements present new challenges for HE quality assurance (QA) and risk management, requiring focus on design processes as well as on design content or product. A new approach to the application of HE, recently adopted by NATO, provides more systematic ordering and control of HE processes and activities to meet the challenges of advanced aircrew systems design. This systematic approach to HE has been applied by MoD to the procurement of mission systems for the Royal Navy Merlin helicopter. In MoD procurement, certification is a judicial function, essentially independent of the service customer and industry contractor. Certification decisions are based on advice from MoD's appointed Acceptance Agency. Test and evaluation (T&E) conducted by the contractor and by the Acceptance Agency provide evidence for certification. Certification identifies limitations of systems upon release to the service. Evidence of compliance with HE standards traditionally forms the main basis of HE certification and significant non-compliance could restrict release. The systems HE approach shows concern for the quality of processes as well as for the content of the product. Human factors certification should be concerned with the quality of HE processes as well as products. Certification should require proof of process as well as proof of content and performance. QA criteria such as completeness, consistency, timeliness, and compatibility provide generic guidelines for

  10. Influence of sulfur in fuel on the properties of diffusion flame soot

    Science.gov (United States)

    Zhao, Yan; Ma, Qingxin; Liu, Yongchun; He, Hong

    2016-10-01

    Previous studies indicate that sulfur in fuel affects the hygroscopicity of soot. However, the issue of the effect of sulfur in fuel on soot properties is not fully understood. Here, the properties of soot prepared from fuel with a variable sulfur content were investigated under lean and rich flame conditions. Lean flame soot was influenced more by sulfur in fuel than rich flame soot. The majority of sulfur in fuel in lean flame was converted to gaseous SO2, while a small fraction appeared as sulfate and bisulfate (referred to as sulfate species) in soot. As the sulfur content in fuel increased, sulfate species in lean flame soot increased nonlinearly, while sulfate species on the surface of lean flame soot increased linearly. The hygroscopicity of lean flame soot from sulfur-containing fuel was enhanced mainly due to sulfate species. Meanwhile, more alkynes were formed in lean flame. The diameter of primary lean flame soot particles increased and accumulation mode particle number concentrations of lean flame soot from sulfur-containing fuel increased as a result of more alkynes. Because the potential effects of soot particles on air pollution development greatly depend on the soot properties, which are related to both chemical aging and combustion conditions, this work will aid in understanding the impacts of soot on air quality and climate.

  11. Sandia National Laboratories Advanced Simulation and Computing (ASC) software quality plan part 2 mappings for the ASC software quality engineering practices, version 2.0.

    Energy Technology Data Exchange (ETDEWEB)

    Heaphy, Robert; Sturtevant, Judith E.; Hodges, Ann Louise; Boucheron, Edward A.; Drake, Richard Roy; Minana, Molly A.; Hackney, Patricia; Forsythe, Christi A.; Schofield, Joseph Richard, Jr. (,; .); Pavlakos, Constantine James; Williamson, Charles Michael; Edwards, Harold Carter

    2006-09-01

    The purpose of the Sandia National Laboratories Advanced Simulation and Computing (ASC) Software Quality Plan is to clearly identify the practices that are the basis for continually improving the quality of ASC software products. The plan defines the ASC program software quality practices and provides mappings of these practices to Sandia Corporate Requirements CPR001.3.2 and CPR001.3.6 and to a Department of Energy document, ''ASCI Software Quality Engineering: Goals, Principles, and Guidelines''. This document also identifies ASC management and software project teams' responsibilities in implementing the software quality practices and in assessing progress towards achieving their software quality goals.

  12. Photochemical treatment as an alternative to improve the quality of wastewater after advanced primary treatment.

    Directory of Open Access Journals (Sweden)

    Hernández Fernando

    2014-12-01

    Full Text Available The present research contains the photochemical treatment (PCT of residual wastewater effluent derived from an advanced primary treatment process (APT. The application employed an ultraviolet light system, hydrogen peroxide and ozone as a free hydroxyl’s radicals generator; strong oxidants for the organic contaminants mineralization which affects the water quality. The aliquots of the APT and PCT were analyzed by determination of the parameters as the color, turbidity, electric conductivity, COD, UV-Vis spectrometry, anion and cation techniques, enabling the determination of the photo-oxidative wastewater treatment efficiency. The microbiological assays denote the one hundred percent photo-oxidative effectiveness for the removal of undesirable microorganisms. After the treatment, the water is suitable for its reuse, commercialization or spill into a body receptor without any risk for the environment or the health.

  13. Fluctuating functions related to quality of life in advanced Parkinson disease: effects of duodenal levodopa infusion

    DEFF Research Database (Denmark)

    Isacson, D; Bingefors, K; Sønbø Kristiansen, Ivar

    2008-01-01

    OBJECTIVE: To assess fluctuations in quality of life (QoL) and motor performance in patients with advanced Parkinson disease (PD) treated with continuous daytime duodenal levodopa/carbidopa infusion or conventional therapy. METHODS: Of 18 patients completing a 6-week trial (DIREQT), 12 were...... followed for up to 6 months and assessed using electronic diaries and the PD Questionnaire-39 (PDQ-39). RESULTS: During the trial and follow-up, major diurnal fluctuations were observed, especially for hyperkinesia, 'off' time, ability to walk and depression. Duodenal infusion was associated...... with significantly more favourable outcomes compared with conventional treatment for satisfaction with overall functioning, 'off' time and ability to walk, with improved outcomes with PDQ-39. CONCLUSIONS: Relative to conventional treatment, infusion therapy may stabilize and significantly improve motor function...

  14. Sandia National Laboratories Advanced Simulation and Computing (ASC) software quality plan. Part 1 : ASC software quality engineering practices version 1.0.

    Energy Technology Data Exchange (ETDEWEB)

    Minana, Molly A.; Sturtevant, Judith E.; Heaphy, Robert; Hodges, Ann Louise; Boucheron, Edward A.; Drake, Richard Roy; Forsythe, Christi A.; Schofield, Joseph Richard, Jr.; Pavlakos, Constantine James; Williamson, Charles Michael; Edwards, Harold Carter

    2005-01-01

    The purpose of the Sandia National Laboratories (SNL) Advanced Simulation and Computing (ASC) Software Quality Plan is to clearly identify the practices that are the basis for continually improving the quality of ASC software products. Quality is defined in DOE/AL Quality Criteria (QC-1) as conformance to customer requirements and expectations. This quality plan defines the ASC program software quality practices and provides mappings of these practices to the SNL Corporate Process Requirements (CPR 1.3.2 and CPR 1.3.6) and the Department of Energy (DOE) document, ASCI Software Quality Engineering: Goals, Principles, and Guidelines (GP&G). This quality plan identifies ASC management and software project teams' responsibilities for cost-effective software engineering quality practices. The SNL ASC Software Quality Plan establishes the signatories commitment to improving software products by applying cost-effective software engineering quality practices. This document explains the project teams opportunities for tailoring and implementing the practices; enumerates the practices that compose the development of SNL ASC's software products; and includes a sample assessment checklist that was developed based upon the practices in this document.

  15. Impact of Duodopa on Quality of Life in Advanced Parkinson's Disease: A UK Case Series

    Directory of Open Access Journals (Sweden)

    T. Foltynie

    2013-01-01

    Full Text Available Treatment options in advanced Parkinson’s disease (PD include subcutaneous apomorphine, pallidal or subthalamic nucleus Deep Brain Stimulation (DBS, or levodopa/carbidopa intestinal gel (LCIG/Duodopa. In this study, we describe the outcome of 12 PD patients with PD related complications started on LCIG, with respect to their quality of life measured by a disease specific validated scale—the PDQ39, together with diaries recording time spent “On,” “Off,” “Dyskinetic,” or “Asleep.” At the time of latest follow up, improvements were observed in both the PDQ39 Summary index as well as diary reports of PD symptom control following introduction of LCIG, supporting its use in well selected patients. The use of a trial period of LCIG via naso-jejunal administration allows objective evaluation of improvement in PD symptom control in advance of the placement of the more invasive percutaneous jejunostomy procedure. The decision to embark on LCIG, apomorphine or DBS should be supported by input from centres with experience of all 3 approaches. Since LCIG is an expensive option, development of the most appropriate future commissioning of this therapy in the absence of Class 1 evidence requires careful scrutiny of the outcomes of its use in a broad range of published series.

  16. FLAME MONITORING IN POWER STATION BOILERS USING IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    K. Sujatha

    2012-05-01

    Full Text Available Combustion quality in power station boilers plays an important role in minimizing the flue gas emissions. In the present work various intelligent schemes to infer the flue gas emissions by monitoring the flame colour at the furnace of the boiler are proposed here. Flame image monitoring involves capturing the flame video over a period of time with the measurement of various parameters like Carbon dioxide (CO2, excess oxygen (O2, Nitrogen dioxide (NOx, Sulphur dioxide (SOx and Carbon monoxide (CO emissions plus the flame temperature at the core of the fire ball, air/fuel ratio and the combustion quality. Higher the quality of combustion less will be the flue gases at the exhaust. The flame video was captured using an infrared camera. The flame video is then split up into the frames for further analysis. The video splitter is used for progressive extraction of the flame images from the video. The images of the flame are then pre-processed to reduce noise. The conventional classification and clustering techniques include the Euclidean distance classifier (L2 norm classifier. The intelligent classifier includes the Radial Basis Function Network (RBF, Back Propagation Algorithm (BPA and parallel architecture with RBF and BPA (PRBFBPA. The results of the validation are supported with the above mentioned performance measures whose values are in the optimal range. The values of the temperatures, combustion quality, SOx, NOx, CO, CO2 concentrations, air and fuel supplied corresponding to the images were obtained thereby indicating the necessary control action taken to increase or decrease the air supply so as to ensure complete combustion. In this work, by continuously monitoring the flame images, combustion quality was inferred (complete/partial/incomplete combustion and the air/fuel ratio can be automatically varied. Moreover in the existing set-up, measurements like NOx, CO and CO2 are inferred from the samples that are collected periodically or by

  17. Advancement in the chemical analysis and quality control of flavonoid in Ginkgo biloba.

    Science.gov (United States)

    Liu, Xin-Guang; Wu, Si-Qi; Li, Ping; Yang, Hua

    2015-09-10

    Flavonoids are the main active constituents in Ginkgo biloba L., which have been suggested to have broad-spectrum free-radical scavenging activities. This review summarizes the recent advances in the chemical analysis of the flavonoids in G. biloba and its finished products (from 2009 to 2014), including chemical composition, sample preparation, separation, detection and different quality criteria. More than 70 kinds of flavonoids have been identified in this plant. In this review, various analytical approaches as well as their chromatographic conditions have been described, and their advantages/disadvantages are also compared. Quantitative analyses of Ginkgo flavonoids applied by most pharmacopeias start with an acidic hydrolysis followed by determination of the resulting aglycones using HPLC. But increasing direct assay of individual flavonol glycosides found that many adulterated products were still qualified by the present tests. To obtain an authentic and applicable analytical approach for quality evaluation of Ginkgo and its finished products, related suggestions and opinions in the recent publications are mainly discussed in this review. This discussion on chemical analyses of Ginkgo flavonoids will also be found as a significant guide for widely varied natural flavonoids.

  18. The Moving Flame Experiment

    OpenAIRE

    Stern, Melvin E.

    2011-01-01

    When a flame is rotated around the outside bottom rim of a cylindrical pan of water initially at rest, D. Fultz has observed that the fluid acquires a net vertical component of angular momentum opposite to the rotation of the heat source. We have repeated this experiment in a cylindrical annulus in order to restrict the radial motions and have found that the same phenomenon occurs. Using a simple model based on the latter experiment we investigate the mechanism by which a fluid can acquire an...

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

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2015-03-01

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

  20. Dynamics and structure of stretched flames

    Energy Technology Data Exchange (ETDEWEB)

    Law, C.K. [Princeton Univ., NJ (United States)

    1993-12-01

    This program aims to gain fundamental understanding on the structure, geometry, and dynamics of laminar premixed flames, and relate these understanding to the practical issues of flame extinction and stabilization. The underlying fundamental interest here is the recent recognition that the response of premixed flames can be profoundly affected by flame stretch, as manifested by flow nonuniformity, flame curvature, and flame/flow unsteadiness. As such, many of the existing understanding on the behavior of premixed flames need to be qualitatively revised. The research program consists of three major thrusts: (1) detailed experimental and computational mapping of the structure of aerodynamically-strained planar flames, with emphasis on the effects of heat loss, nonequidiffusion, and finite residence time on the flame thickness, extent of incomplete reaction, and the state of extinction. (2) Analytical study of the geometry and dynamics of stretch-affected wrinkled flame sheets in simple configurations, as exemplified by the Bunsen flame and the spatially-periodic flame, with emphasis on the effects of nonlinear stretch, the phenomena of flame cusping, smoothing, and tip opening, and their implications on the structure and burning rate of turbulent flames. (3) Stabilization and blowoff of two-dimensional inverted premixed and stabilization and determining the criteria governing flame blowoff. The research is synergistically conducted through the use of laser-based diagnostics, computational simulation of the flame structure with detailed chemistry and transport, and mathematical analysis of the flame dynamics.

  1. Editorial: Advances in healthcare provider and patient training to improve the quality and safety of patient care

    OpenAIRE

    Borycki, Elizabeth M

    2015-01-01

    This special issue of the Knowledge Management & E-Learning: An International Journal is dedicated to describing “Advances in Healthcare Provider and Patient Training to Improve the Quality and Safety of Patient Care.” Patient safety is an important and fundamental requirement of ensuring the quality of patient care. Training and education has been identified as a key to improving healthcare provider patient safety competencies especially when working with new technologies such as electronic ...

  2. Understanding the impact of recent advances in isoprene photooxidation on simulations of regional air quality

    Directory of Open Access Journals (Sweden)

    Y. Xie

    2013-08-01

    Full Text Available The CMAQ (Community Multiscale Air Quality us model in combination with observations for INTEX-NA/ICARTT (Intercontinental Chemical Transport Experiment–North America/International Consortium for Atmospheric Research on Transport and Transformation 2004 are used to evaluate recent advances in isoprene oxidation chemistry and provide constraints on isoprene nitrate yields, isoprene nitrate lifetimes, and NOx recycling rates. We incorporate recent advances in isoprene oxidation chemistry into the SAPRC-07 chemical mechanism within the US EPA (United States Environmental Protection Agency CMAQ model. The results show improved model performance for a range of species compared against aircraft observations from the INTEX-NA/ICARTT 2004 field campaign. We further investigate the key processes in isoprene nitrate chemistry and evaluate the impact of uncertainties in the isoprene nitrate yield, NOx (NOx = NO + NO2 recycling efficiency, dry deposition velocity, and RO2 + HO2 reaction rates. We focus our examination on the southeastern United States, which is impacted by both abundant isoprene emissions and high levels of anthropogenic pollutants. We find that NOx concentrations increase by 4–9% as a result of reduced removal by isoprene nitrate chemistry. O3 increases by 2 ppbv as a result of changes in NOx. OH concentrations increase by 30%, which can be primarily attributed to greater HOx production. We find that the model can capture observed total alkyl and multifunctional nitrates (∑ANs and their relationship with O3 by assuming either an isoprene nitrate yield of 6% and daytime lifetime of 6 hours or a yield of 12% and lifetime of 4 h. Uncertainties in the isoprene nitrates can impact ozone production by 10% and OH concentrations by 6%. The uncertainties in NOx recycling efficiency appear to have larger effects than uncertainties in isoprene nitrate yield and dry deposition velocity. Further progress depends on improved understanding of

  3. Establishing a portfolio of quality-improvement projects in pediatric surgery through advanced improvement leadership systems.

    Science.gov (United States)

    Gerrein, Betsy T; Williams, Christina E; Von Allmen, Daniel

    2013-01-01

    Formal quality-improvement (QI) projects require that participants are educated in QI methods to provide them with the capability to carry out successful, meaningful work. However, orchestrating a portfolio of projects that addresses the strategic mission of the institution requires an extension of basic QI training to provide the division or business unit with the capacity to successfully develop and manage the portfolio. Advanced Improvement Leadership Systems is a program to help units create a meaningful portfolio. This program, used by the Division of Pediatric General and Thoracic Surgery at Cincinnati Children's Hospital Medical Center, helped establish a portfolio of targeted QI projects designed to achieve outstanding outcomes at competitive costs in multiple clinical areas aligned with the institution's strategic goals (improve disease-based outcomes, patient safety, flow, and patient and family experience). These objectives are addressed in an institutional strategic plan built around 5 core areas: Safety, Productivity, Care Coordination and Outcomes, Patient and Family Experience, and Value. By combining the portfolio of QI projects with improvements in the divisional infrastructure, effective improvement efforts were realized throughout the division. In the 9 months following the program, divisional capability resulted in a 16.5% increase (5.7% to 22.2%) of formally trained staff working on 10 QI teams. Concurrently, a leadership team, designed to coordinate projects, remove barriers, and provide technical support, provided the capacity to pursue this ongoing effort. The Advanced Improvement Leadership Systems program increased the Division's efficiency and effectiveness in pursing the QI mission that is integral at our hospital. PMID:24361020

  4. The Quality-of-Life Effects of Neoadjuvant Chemoradiation in Locally Advanced Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Herman, Joseph M., E-mail: jherma15@jhmi.edu [Department of Radiation Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Narang, Amol K. [Department of Radiation Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Griffith, Kent A. [Department of Biostatistics, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Zalupski, Mark M. [Department of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Reese, Jennifer B. [Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Gearhart, Susan L. [Department of Medical Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Azad, Nolifer S. [Department of Medical Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Chan, June; Olsen, Leah [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Efron, Jonathan E. [Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Lawrence, Theodore S.; Ben-Josef, Edgar [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)

    2013-01-01

    Purpose: Existing studies that examine the effect of neoadjuvant chemoradiation (CRT) for locally advanced rectal cancer on patient quality of life (QOL) are limited. Our goals were to prospectively explore acute changes in patient-reported QOL endpoints during and after treatment and to establish a distribution of scores that could be used for comparison as new treatment modalities emerge. Methods and Materials: Fifty patients with locally advanced rectal cancer were prospectively enrolled at 2 institutions. Validated cancer-specific European Organization for Research and Treatment of Cancer (EORTC QLQ-CR30) and colorectal cancer-specific (EORTC QLQ-CR38 and EORTC QLQ-CR 29) QOL questionnaires were administered to patients 1 month before they began CRT, at week 4 of CRT, and 1 month after they had finished CRT. The questionnaires included multiple symptom scales, functional domains, and a composite global QOL score. Additionally, a toxicity scale was completed by providers 1 month before the beginning of CRT, weekly during treatment, and 1 month after the end of CRT. Results: Global QOL showed a statistically significant and borderline clinically significant decrease during CRT (-9.50, P=.0024) but returned to baseline 1 month after the end of treatment (-0.33, P=.9205). Symptoms during treatment were mostly gastrointestinal (nausea/vomiting +9.94, P<.0001; and diarrhea +16.67, P=.0022), urinary (dysuria +13.33, P<.0001; and frequency +11.82, P=.0006) or fatigue (+16.22, P<.0001). These symptoms returned to baseline after therapy. However, sexual enjoyment (P=.0236) and sexual function (P=.0047) remained persistently diminished after therapy. Conclusions: Rectal cancer patients undergoing neoadjuvant CRT may experience a reduction in global QOL along with significant gastrointestinal and genitourinary symptoms during treatment. Moreover, provider-rated toxicity scales may not fully capture this decrease in patient-reported QOL. Although most symptoms are transient

  5. Establishing a portfolio of quality-improvement projects in pediatric surgery through advanced improvement leadership systems.

    Science.gov (United States)

    Gerrein, Betsy T; Williams, Christina E; Von Allmen, Daniel

    2013-01-01

    Formal quality-improvement (QI) projects require that participants are educated in QI methods to provide them with the capability to carry out successful, meaningful work. However, orchestrating a portfolio of projects that addresses the strategic mission of the institution requires an extension of basic QI training to provide the division or business unit with the capacity to successfully develop and manage the portfolio. Advanced Improvement Leadership Systems is a program to help units create a meaningful portfolio. This program, used by the Division of Pediatric General and Thoracic Surgery at Cincinnati Children's Hospital Medical Center, helped establish a portfolio of targeted QI projects designed to achieve outstanding outcomes at competitive costs in multiple clinical areas aligned with the institution's strategic goals (improve disease-based outcomes, patient safety, flow, and patient and family experience). These objectives are addressed in an institutional strategic plan built around 5 core areas: Safety, Productivity, Care Coordination and Outcomes, Patient and Family Experience, and Value. By combining the portfolio of QI projects with improvements in the divisional infrastructure, effective improvement efforts were realized throughout the division. In the 9 months following the program, divisional capability resulted in a 16.5% increase (5.7% to 22.2%) of formally trained staff working on 10 QI teams. Concurrently, a leadership team, designed to coordinate projects, remove barriers, and provide technical support, provided the capacity to pursue this ongoing effort. The Advanced Improvement Leadership Systems program increased the Division's efficiency and effectiveness in pursing the QI mission that is integral at our hospital.

  6. Control of the flame front advance in a sintering bed of iron ores; Control del avance del frente de llama en el lecho de sinterizacion de minerales de hierro

    Energy Technology Data Exchange (ETDEWEB)

    Cores, A.; Mochon, J.; Ruiz-Bustinza, I.; Parra, R.

    2010-07-01

    A sintering pan of 40 cm cubed is loaded with a mixture of iron ores, limestone and coke weighing 110 kg in a sintering pilot plant. In this sintering pan, a series of thermocouples have been introduced at different depths. Tests have been carried out to study the width of the combustion zone and the maximum temperature of the flame front across the sintering bed. For the analysis of the results, a data acquisition system was used. This consisted of two modules connected in serie, for performing the analogue-digital conversion. The analogue entry point is the exit point of the thermocouples and the digital exit point was the temperature average. A computer was used for conserving and storing the data and for carrying out interpolations, simulating the state and evolution of the flame front across the bed. (Author) 21 refs.

  7. Premixed flame propagation in vertical tubes

    CERN Document Server

    Kazakov, Kirill A

    2015-01-01

    Analytical treatment of premixed flame propagation in vertical tubes with smooth walls is given. Using the on-shell flame description, equations describing quasi-steady flame with a small but finite front thickness are obtained and solved numerically. It is found that near the limits of inflammability, solutions describing upward flame propagation come in pairs having close propagation speeds, and that the effect of gravity is to reverse the burnt gas velocity profile generated by the flame. On the basis of these results, a theory of partial flame propagation driven by the gravitational field is developed. A complete explanation is given of the intricate observed behavior of limit flames, including dependence of the inflammability range on the size of the combustion domain, the large distances of partial flame propagation, and the progression of flame extinction. The role of the finite front-thickness effects is discussed in detail. Also, various mechanisms governing flame acceleration in smooth tubes are ide...

  8. Advancing the quality of oncology nursing care: Interlink Community Cancer Nurses' model for reflective practice.

    Science.gov (United States)

    Howell, D; Pelton, B

    2001-01-01

    Since 1996, Interlink Community Cancer Nurses have been using reflective practice as a team to share knowledge and experience amongst peers. The use of reflective practice enables the nurse to examine decision-making in patient situations and uncover the knowledge and artistry that is embedded in nursing practice. This article describes how reflection is practised by specialist cancer nurses to advance the quality of caregiving. The use of a structured framework for reflection which incorporates ways of knowing in nursing is an essential feature of the Interlink model for reflection. The development of a process for reflection within the Interlink program has at times been challenging. However, the Interlink nurses' experience with reflection is believed to be critical to the ongoing development of the program and the individual nurse. Interlink nurses have found that guided reflection, the creation of an environmental milieu for reflection and personal knowing, and self-evaluation are critical to the process of becoming a self-reflective practitioner. PMID:11842450

  9. Health-Related Quality of Life after surgery for primary advanced rectal cancer and recurrent rectal cancer

    DEFF Research Database (Denmark)

    Thaysen, Henriette Vind; Jess, Per; Laurberg, Søren

    2012-01-01

    Aim: A review of the literature was undertaken to provide an overview of Health-related quality of life (HRQoL) after surgery for primary advanced or recurrent rectal cancer and to outline proposals for future HRQoL studies in this area. Method: A systematic literature search was undertaken. Only...... studies concerning surgery for primary advanced or recurrent rectal cancer and describing methods used for measuring HRQoL were considered. Results Seven studies were identified including two prospective longitudinal, three cross-sectional and two based on qualitative data. Global quality of life...... cancer. Larger prospective longitudinal studies are needed to improve information on the effects of this extensive surgery on quality of life....

  10. Electrical Aspects of Impinging Flames

    Science.gov (United States)

    Chien, Yu-Chien

    This dissertation examines the use of electric fields as one mechanism for controlling combustion as flames are partially extinguished when impinging on nearby surfaces. Electrical aspects of flames, specifically, the production of chemi-ions in hydrocarbon flames and the use of convective flows driven by these ions, have been investigated in a wide range of applications in prior work but despite this fairly comprehensive effort to study electrical aspects of combustion, relatively little research has focused on electrical phenomena near flame extinguishment, nor for flames near impingement surfaces. Electrical impinging flames have complex properties under global influences of ion-driven winds and flow field disturbances from the impingement surface. Challenges of measurements when an electric field is applied in the system have limited an understanding of changes to the flame behavior and species concentrations caused by the field. This research initially characterizes the ability of high voltage power supplies to respond on sufficiently short time scales to permit real time electrical flame actuation. The study then characterizes the influence of an electric field on the impinging flame shape, ion current and flow field of the thermal plume associated with the flame. The more significant further examinations can be separated into two parts: 1) the potential for using electric fields to control the release of carbon monoxide (CO) from surface-impinging flames, and 2) an investigation of controlling electrically the heat transfer to a plate on which the flame impinges. Carbon monoxide (CO) results from the incomplete oxidation of hydrocarbon fuels and, while CO can be desirable in some syngas processes, it is usually a dangerous emission from forest fires, gas heaters, gas stoves, or furnaces where insufficient oxygen in the core reaction does not fully oxidize the fuel to carbon dioxide and water. Determining how carbon monoxide is released and how heat transfer

  11. The Quality-of-Life Effects of Neoadjuvant Chemoradiation in Locally Advanced Rectal Cancer

    International Nuclear Information System (INIS)

    Purpose: Existing studies that examine the effect of neoadjuvant chemoradiation (CRT) for locally advanced rectal cancer on patient quality of life (QOL) are limited. Our goals were to prospectively explore acute changes in patient-reported QOL endpoints during and after treatment and to establish a distribution of scores that could be used for comparison as new treatment modalities emerge. Methods and Materials: Fifty patients with locally advanced rectal cancer were prospectively enrolled at 2 institutions. Validated cancer-specific European Organization for Research and Treatment of Cancer (EORTC QLQ-CR30) and colorectal cancer-specific (EORTC QLQ-CR38 and EORTC QLQ-CR 29) QOL questionnaires were administered to patients 1 month before they began CRT, at week 4 of CRT, and 1 month after they had finished CRT. The questionnaires included multiple symptom scales, functional domains, and a composite global QOL score. Additionally, a toxicity scale was completed by providers 1 month before the beginning of CRT, weekly during treatment, and 1 month after the end of CRT. Results: Global QOL showed a statistically significant and borderline clinically significant decrease during CRT (−9.50, P=.0024) but returned to baseline 1 month after the end of treatment (−0.33, P=.9205). Symptoms during treatment were mostly gastrointestinal (nausea/vomiting +9.94, P<.0001; and diarrhea +16.67, P=.0022), urinary (dysuria +13.33, P<.0001; and frequency +11.82, P=.0006) or fatigue (+16.22, P<.0001). These symptoms returned to baseline after therapy. However, sexual enjoyment (P=.0236) and sexual function (P=.0047) remained persistently diminished after therapy. Conclusions: Rectal cancer patients undergoing neoadjuvant CRT may experience a reduction in global QOL along with significant gastrointestinal and genitourinary symptoms during treatment. Moreover, provider-rated toxicity scales may not fully capture this decrease in patient-reported QOL. Although most symptoms are

  12. Understanding the impact of recent advances in isoprene photooxidation on simulations of regional air quality

    Directory of Open Access Journals (Sweden)

    Y. Xie

    2012-10-01

    Full Text Available The CMAQ model in combination with observations for INTEX-NA/ICARTT 2004 are used to evaluate recent advances in isoprene oxidation chemistry and provide constraints on isoprene nitrate yields, isoprene nitrate lifetimes, and NOx recycling rates. We incorporate recent advances in isoprene oxidation chemistry into the SAPRC-07 chemical mechanism within the US EPA Community Multiscale Air Quality (CMAQ model. The results show improved model performance for a range of species compared against aircraft observations from the INTEX-NA/ICARTT 2004 field campaign. We further investigate the key processes in isoprene nitrate chemistry and evaluate the impact of uncertainties in the isoprene nitrate yield, NOx (NOx = NO + NO2 recycling efficiency, dry deposition velocity, and RO2 + HO2 reaction rates. We focus our examination in the Southeastern United States, which is impacted by both abundant isoprene emissions and high levels of anthropogenic pollutants. We find that NOx concentrations increase by 4–9% as a result of reduced removal by isoprene nitrate chemistry. O3 increases by 2 ppbv as a result of changes in NOx. OH concentrations increase by 30%, which can be primarily attributed to greater HOx production. We find that the model can capture observed total alkyl and multifunctional nitrates (∑ANs and their relationship with O3, by assuming either an isoprene nitrate yield of 6% and daytime lifetime of 6 h or a yield of 12% and lifetime of 4 h. Uncertainties in the isoprene nitrates can impact ozone production by 10% and OH concentrations by 6%. The uncertainties in NOx recycling efficiency appear to have larger effects than uncertainties in isoprene nitrate yield and dry deposition velocity. Further progress depends on improved understanding of isoprene oxidation pathways, the rate of NOx recycling from

  13. FABRICATION PROCESS AND PRODUCT QUALITY IMPROVEMENTS IN ADVANCED GAS REACTOR UCO KERNELS

    Energy Technology Data Exchange (ETDEWEB)

    Charles M Barnes

    2008-09-01

    A major element of the Advanced Gas Reactor (AGR) program is developing fuel fabrication processes to produce high quality uranium-containing kernels, TRISO-coated particles and fuel compacts needed for planned irradiation tests. The goals of the AGR program also include developing the fabrication technology to mass produce this fuel at low cost. Kernels for the first AGR test (“AGR-1) consisted of uranium oxycarbide (UCO) microspheres that werre produced by an internal gelation process followed by high temperature steps tot convert the UO3 + C “green” microspheres to first UO2 + C and then UO2 + UCx. The high temperature steps also densified the kernels. Babcock and Wilcox (B&W) fabricated UCO kernels for the AGR-1 irradiation experiment, which went into the Advance Test Reactor (ATR) at Idaho National Laboratory in December 2006. An evaluation of the kernel process following AGR-1 kernel production led to several recommendations to improve the fabrication process. These recommendations included testing alternative methods of dispersing carbon during broth preparation, evaluating the method of broth mixing, optimizing the broth chemistry, optimizing sintering conditions, and demonstrating fabrication of larger diameter UCO kernels needed for the second AGR irradiation test. Based on these recommendations and requirements, a test program was defined and performed. Certain portions of the test program were performed by Oak Ridge National Laboratory (ORNL), while tests at larger scale were performed by B&W. The tests at B&W have demonstrated improvements in both kernel properties and process operation. Changes in the form of carbon black used and the method of mixing the carbon prior to forming kernels led to improvements in the phase distribution in the sintered kernels, greater consistency in kernel properties, a reduction in forming run time, and simplifications to the forming process. Process parameter variation tests in both forming and sintering steps led

  14. Land Surface Microwave Emissivities Derived from AMSR-E and MODIS Measurements with Advanced Quality Control

    Science.gov (United States)

    Moncet, Jean-Luc; Liang, Pan; Galantowicz, John F.; Lipton, Alan E.; Uymin, Gennady; Prigent, Catherine; Grassotti, Christopher

    2011-01-01

    A microwave emissivity database has been developed with data from the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and with ancillary land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the same Aqua spacecraft. The primary intended application of the database is to provide surface emissivity constraints in atmospheric and surface property retrieval or assimilation. An additional application is to serve as a dynamic indicator of land surface properties relevant to climate change monitoring. The precision of the emissivity data is estimated to be significantly better than in prior databases from other sensors due to the precise collocation with high-quality MODIS LST data and due to the quality control features of our data analysis system. The accuracy of the emissivities in deserts and semi-arid regions is enhanced by applying, in those regions, a version of the emissivity retrieval algorithm that accounts for the penetration of microwave radiation through dry soil with diurnally varying vertical temperature gradients. These results suggest that this penetration effect is more widespread and more significant to interpretation of passive microwave measurements than had been previously established. Emissivity coverage in areas where persistent cloudiness interferes with the availability of MODIS LST data is achieved using a classification-based method to spread emissivity data from less-cloudy areas that have similar microwave surface properties. Evaluations and analyses of the emissivity products over homogeneous snow-free areas are presented, including application to retrieval of soil temperature profiles. Spatial inhomogeneities are the largest in the vicinity of large water bodies due to the large water/land emissivity contrast and give rise to large apparent temporal variability in the retrieved emissivities when satellite footprint locations vary over time. This issue will be dealt with in the future by

  15. Quality of dying in nursing home residents dying with dementia: does advanced care planning matter? A nationwide postmortem study.

    Directory of Open Access Journals (Sweden)

    An Vandervoort

    Full Text Available Advance care planning is considered a central component of good quality palliative care and especially relevant for people who lose the capacity to make decisions at the end of life, which is the case for many nursing home residents with dementia. We set out to investigate to what extent (1 advance care planning in the form of written advance patient directives and verbal communication with patient and/or relatives about future care and (2 the existence of written advance general practitioner orders are related to the quality of dying of nursing home residents with dementia.Cross-sectional study of deaths (2010 using random cluster-sampling. Representative sample of nursing homes in Flanders, Belgium. Deaths of residents with dementia in a three-month period were reported; for each the nurse most involved in care, GP and closest relative completed structured questionnaires.We identified 101 deaths of residents with dementia in 69 nursing homes (58% response rate. A written advance patient directive was present for 17.5%, GP-orders for 56.7%. Controlling for socio-demographic/clinical characteristics in multivariate regression analyses, chances of having a higher mean rating of emotional well-being (less fear and anxiety on the Comfort Assessment in Dying with Dementia scale were three times higher with a written advance patient directive and more specifically when having a do-not-resuscitate order (AOR 3.45; CI,1.1-11 than for those without either (AOR 2.99; CI,1.1-8.3. We found no association between verbal communication or having a GP order and quality of dying.For nursing home residents with dementia there is a strong association between having a written advance directive and quality of dying. Where wishes are written, relatives report lower levels of emotional distress at the end of life. These results underpin the importance of advance care planning for people with dementia and beginning this process as early as possible.

  16. Effect of Intermittent Androgen Blockade on the Quality of Life of Patients with Advanced Prostate Carcinoma

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    OBJECTIVE To investigate the effect of intermittent androgen blockade (IAB) on the quality of life (QOL) of patients with advanced prostatic carcinoma (APC).METHODS Investigations on the QOL of 51 APC patients receiving IAB treatment, totaling 3 times, i.e. 6 months before and after, and 12 months after treatment, were perform using the EORTC QLQ-C30 measuring scale and QLQ-PR25 scale.RESULTS Although IAB became an economic burden for the families, it was lessened during the intermission (P<0.05). The overall health status significantly improved 6 months after IAB treatment (P<0.01), especially during the intermission (P<0.05), with a total or local easement of pain (P<0.01) and an improvement of urinary function (P<0.01). Although there was impairment,to various degrees, in many functions of the patients on the 6th month of treatment, such as the physical function (P<0.05), role function (P<0.05), the emotional (P<0.01) and the social functions (P<0.01), with an enhancement of fatigue (P<0.01), these functions gradually recovered by the 12th month as the intermission started. Treatment-related symptoms such as flushing and mammary swelling significantly emerged on the 6th treatment month (P<0.01), and lessened on the 12th (P<0.01). During the treatment period,therewas an notable drop in sexual interest (P<0.01), with a deprivation of sex life, but revived to various degrees during the intermission (P<0.01).CONCLUSION Although IAB treatment of APC patients did impair the physiologic and psychologic status of patients to varying degrees, these were improved and restored during the intermission.

  17. Hybrid algorithm for three-dimensional flame chemiluminescence tomography based on imaging overexposure compensation.

    Science.gov (United States)

    Jin, Ying; Song, Yang; Qu, Xiangju; Li, Zhenhua; Ji, Yunjing; He, Anzhi

    2016-08-01

    Flame tomography of chemiluminescence is a necessary combustion diagnostic technique that provides instantaneous 3D information on flame structure and excited species concentrations. During combustion diagnostics, imaging overexposure always causes missing information, which obviously decreases the accuracy in further reconstructions. In order to compensate imaging overexposure, a hybrid algorithm combining weight correction and Tikhonov's regularization is proposed in this paper. The intensity of the overexposure region can be estimated via the accumulation of weight coefficients. Meanwhile, Tikhonov's regularization is utilized to ameliorate the quality of reconstruction. The numerical simulation quantitatively evaluates the performance of the hybrid algorithm. Additionally, an experiment system consisting of 12 cameras was established to reconstruct the 3D combustion structure of axisymmetric flame with different exposure time settings. This work further investigates dynamic nonaxisymmetric propane diffusion flame. The obtained results show that the hybrid algorithm can effectively reveal the flame structure less influenced by imaging overexposure and achieve better results. PMID:27505371

  18. Why Do Electricity Policy and Competitive Markets Fail to Use Advanced PV Systems to Improve Distribution Power Quality?

    Directory of Open Access Journals (Sweden)

    Mark P. McHenry

    2016-01-01

    Full Text Available The increasing pressure for network operators to meet distribution network power quality standards with increasing peak loads, renewable energy targets, and advances in automated distributed power electronics and communications is forcing policy-makers to understand new means to distribute costs and benefits within electricity markets. Discussions surrounding how distributed generation (DG exhibits active voltage regulation and power factor/reactive power control and other power quality capabilities are complicated by uncertainties of baseline local distribution network power quality and to whom and how costs and benefits of improved electricity infrastructure will be allocated. DG providing ancillary services that dynamically respond to the network characteristics could lead to major network improvements. With proper market structures renewable energy systems could greatly improve power quality on distribution systems with nearly no additional cost to the grid operators. Renewable DG does have variability challenges, though this issue can be overcome with energy storage, forecasting, and advanced inverter functionality. This paper presents real data from a large-scale grid-connected PV array with large-scale storage and explores effective mitigation measures for PV system variability. We discuss useful inverter technical knowledge for policy-makers to mitigate ongoing inflation of electricity network tariff components by new DG interconnection requirements or electricity markets which value power quality and control.

  19. Quality of life assessment in advanced cancer patients treated at home, an inpatient unit, and a day care center

    OpenAIRE

    Leppert, Wojciech; Majkowicz, Mikolaj; Forycka, Maria; Mess, Eleonora; Zdun-Ryzewska, Agata

    2014-01-01

    Aim of the study To assess quality of life (QoL) in cancer patients treated at home, at an in-patient palliative care unit (PCU), and at a day care center (DCC). Patients and methods QoL was assessed in advanced cancer patients at baseline and after 7 days of symptomatic treatment using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 15-Palliative Care (EORTC QLQ-C15-PAL), the Edmonton Symptom Assessment System (ESAS), and the Karnofsky Perfor...

  20. Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Menapace, J A; Schaffers, K I; Bayramian, A J; Davis, P J; Ebbers, C A; Wolfe, J E; Caird, J A; Barty, C J

    2008-02-26

    Advanced magnetorheological finishing (MRF) techniques have been applied to Ti:sapphire crystals to compensate for sub-millimeter lattice distortions that occur during the crystal growing process. Precise optical corrections are made by imprinting topographical structure onto the crystal surfaces to cancel out the effects of the lattice distortion in the transmitted wavefront. This novel technique significantly improves the optical quality for crystals of this type and sets the stage for increasing the availability of high-quality large-aperture sapphire and Ti:sapphire optics in critical applications.

  1. Free Speech, Quality Control, and Flame Wars

    Science.gov (United States)

    Leary, Patrick; Labanowski, Jan K.; Korenman, Joan

    2007-01-01

    The authors who happened to be moderators of academic online discussions bring tales from the trenches. Whether it's computational chemistry, the history of the book, or women's studies, the technology and the users can both prove difficult. The first author talks about two scholarly discussion lists. SHARP-L, whose name comes from the Society for…

  2. Advanced Taste Sensors Based on Artificial Lipids with Global Selectivity to Basic Taste Qualities and High Correlation to Sensory Scores

    OpenAIRE

    Yoshikazu Kobayashi; Masaaki Habara; Hidekazu Ikezazki; Ronggang Chen; Yoshinobu Naito; Kiyoshi Toko

    2010-01-01

    Effective R&D and strict quality control of a broad range of foods, beverages, and pharmaceutical products require objective taste evaluation. Advanced taste sensors using artificial-lipid membranes have been developed based on concepts of global selectivity and high correlation with human sensory score. These sensors respond similarly to similar basic tastes, which they quantify with high correlations to sensory score. Using these unique properties, these sensors can quantify the basic t...

  3. A study of the relationships between perceived pain, social support, coping and quality of life in patients with advanced cancer

    OpenAIRE

    Wright, Shelagh

    1999-01-01

    The aim of the study was to assess the implications of perceived pain and social support for coping ability, levels of distress and quality of life in a group of patients with advanced cancer. A total of 98 patients who were undergoing palliative treatment and/or care and were aware of their cancer diagnosis, but not necessarily of their prognosis, consented verbally to participate. A questionnaire was administered to each participant comprised of scales to measure perceived pain intensity an...

  4. Advanced Quality Control Theory for Training and Education: A Guide to Optimizing Training and Education Efforts

    Science.gov (United States)

    Heppler, Brad

    2008-01-01

    This is a book about quality and how to control quality through deliberate actions on the part of the professionals developing and implementing the instances of instruction available at an organization. Quality control theory favors no particular learning philosophy and is only directed towards aspects of how, what, where and when measurements are…

  5. 新型成炭剂在聚合物膨胀阻燃中的应用和研究进展%Advance in Application and Research of Novel Charring Agents in Intumescent Flame Retardant Polymers

    Institute of Scientific and Technical Information of China (English)

    陈绪煌; 黄碧伟; 龙鹏; 邢为高

    2011-01-01

    The charring agent in tranditional intumescent flame retardants (IFR) are some small molecule alcoholates, which make the flame retardants have easy moisture absorption, easy migration and incompatible to polymer matrix. To improve these faults, some novel charring agents were researched. This article reviewed the applications and researches of some novel charring agents, such as novolac resin; polyamide; thermoplastic polyurethane and some derivatives of macromolecule compounds in IFR polymers.%传统膨胀型阻燃剂中炭源为小分子醇类化合物,导致阻燃剂具有易吸湿、易迁移、和聚合物基体不相容等缺点。为了改进这些缺点,各种新型成炭剂相继被研究开发出来。本文对一些新型成炭剂,如热塑性酚醛树脂、聚酰胺、热塑性聚氨酯以及一些大分子化合物的衍生物在化学膨胀阻燃聚合物中的应用和研究进行了综述。

  6. DOES URINARY DIVERSION IMPROVE THE QUALITY OF LIFE IN OBSTRUCTIVE UROPATHY SECONDARY TO ADVANCED PELVIC MALIGNANCY?

    Directory of Open Access Journals (Sweden)

    Shivashankarappa

    2016-02-01

    Full Text Available INTRODUCTION The incidence of patients presenting with advanced pelvic malignancy with obstructive uropathy is high in our country. Relentless progress of the malignancy will cause deterioration of renal function, aggravation of pain, infection, deterioration of Quality of Life (QOL, uremia and death. Decreased renal function is considered as a contraindication for palliative chemo and radiotherapy. However urinary diversion in these patients will lead to improvement in renal function and may help in administration of palliative therapy and thus, improve the quality of life of these patients. MATERIALS AND METHODS The present study includes the obstructive uropathy patients secondary to pelvic malignancy referred to our institution for urinary diversion between Jan 2010 to Dec 2014. Total 40 patients were included, of which, 25 patients underwent PCN, 9 patients retrograde DJ stenting, 4 patients refused the treatment, 2 patients were not fit for any intervention due to coagulopathy & comorbid conditions. Of 34 treated patients, 30 were female patients and 4 were male patients. All the patients were explained about the procedure and proper consent taken. Laboratory investigations like CBC, coagulation profile, LFT, routine urine analysis, urine C&S and serum electrolytes were carried out. Haemodialysis was done for 10 patients whose serum creatinine was >6mg% & potassium >6meq. USG guided PCN insertion was done in 8 patients, and in those who failed in this procedure, fluoroscopic C-ARM guided PCN insertion done in 17 patients. Post operatively RFT and serum electrolytes were assessed on 3, 7, 15, & 30th day. PCN catheter was changed once in 3 months. RESULTS 8 patients succeeded in USG guided PCN insertion and 17 patients who failed USG PCN insertion, was done under C–Arm guidance. 3 patients received blood transfusion. No deaths were seen during or post procedure in the hospital. Renal functions improved and normalised in most of the

  7. Role of the outer-edge flame on flame extinction in nitrogen-diluted non-premixed counterflow flames with finite burner diameters

    KAUST Repository

    Chung, Yong Ho

    2013-03-01

    This study of nitrogen-diluted non-premixed counterflow flames with finite burner diameters investigates the important role of the outer-edge flame on flame extinction through experimental and numerical analyses. It explores flame stability diagrams mapping the flame extinction response of nitrogen-diluted non-premixed counterflow flames to varying global strain rates in terms of burner diameter, burner gap, and velocity ratio. A critical nitrogen mole fraction exists beyond which the flame cannot be sustained; the critical nitrogen mole fraction versus global strain rate curves have C-shapes for various burner diameters, burner gaps, and velocity ratios. At sufficiently high strain-rate flames, these curves collapse into one curve; therefore, the flames follow the one-dimensional flame response of a typical diffusion flame. Low strain-rate flames are significantly affected by radial conductive heat loss, and therefore flame length. Three flame extinction modes are identified: flame extinction through shrinkage of the outer-edge flame with or without oscillations at the outer-edge flame prior to the extinction, and flame extinction through a flame hole at the flame center. The extinction modes are significantly affected by the behavior of the outer-edge flame. Detailed explanations are provided based on the measured flame-surface temperature and numerical evaluation of the fractional contribution of each term in the energy equation. Radial conductive heat loss at the flame edge to ambience is the main mechanism of extinction through shrinkage of the outer-edge flame in low strain-rate flames. Reduction of the burner diameter can extend the flame extinction mode by shrinking the outer-edge flame in higher strain-rate flames. © 2012 Elsevier Ltd. All rights reserved.

  8. 33 CFR 154.822 - Detonation arresters, flame arresters, and flame screens.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Detonation arresters, flame arresters, and flame screens. 154.822 Section 154.822 Navigation and Navigable Waters COAST GUARD... BULK Vapor Control Systems § 154.822 Detonation arresters, flame arresters, and flame screens. (a)...

  9. Advanced methods of process/quality control in nuclear reactor fuel manufacture. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    Nuclear fuel plays an essential role in ensuring the competitiveness of nuclear energy and its acceptance by the public. The economic and market situation is not favorable at present for nuclear fuel designers and suppliers. The reduction in fuel prices (mainly to compete with fossil fuels) and in the number of fuel assemblies to be delivered to customers (mainly due to burnup increase) has been offset by the rising number of safety and other requirements, e.g. the choice of fuel and structural materials and the qualification of equipment. In this respect, higher burnup and thermal rates, longer fuel cycles and the use of MOX fuels are the real means to improve the economics of the nuclear fuel cycle as a whole. Therefore, utilities and fuel vendors have recently initiated new research and development programmes aimed at improving fuel quality, design and materials to produce robust and reliable fuel for safe and reliable reactor operation more demanding conditions. In this connection, improvement of fuel quality occupies an important place and this requires continuous effort on the part of fuel researchers, designers and producers. In the early years of commercial fuel fabrication, emphasis was given to advancements in quality control/quality assurance related mainly to the product itself. Now, the emphasis is transferred to improvements in process control and to implementation of overall total quality management (TQM) programmes. In the area of fuel quality control, statistical methods are now widely implemented, replacing 100% inspection. The IAEA, recognizing the importance of obtaining and maintaining high standards in fuel fabrication, has paid particular attention to this subject. In response to the rapid progress in development and implementation of advanced methods of process/quality control in nuclear fuel manufacture and on the recommendation of the International Working Group on Water Reactor Fuel Performance and Technology, the IAEA conducted a

  10. Asymptotic analysis of outwardly propagating spherical flames

    Institute of Scientific and Technical Information of China (English)

    Yun-Chao Wu; Zheng Chen

    2012-01-01

    Asymptotic analysis is conducted for outwardly propagating spherical flames with large activation energy.The spherical flame structure consists of the preheat zone,reaction zone,and equilibrium zone.Analytical solutions are separately obtained in these three zones and then asymptotically matched.In the asymptotic analysis,we derive a correlation describing the spherical flame temperature and propagation speed changing with the flame radius.This correlation is compared with previous results derived in the limit of infinite value of activation energy.Based on this correlation,the properties of spherical flame propagation are investigated and the effects of Lewis number on spherical flame propagation speed and extinction stretch rate are assessed.Moreover,the accuracy and performance of different models used in the spherical flame method are examined.It is found that in order to get accurate laminar flame speed and Markstein length,non-linear models should be used.

  11. Organ function and quality of life after transoral laser microsurgery and adjuvant radiotherapy for locally advanced laryngeal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Olthoff, Arno; Hess, Clemens F. [Dept. of Phoniatrics and Pedaudiology, Univ. of Goettingen (Germany); Ewen, Andreas; Wolff, Hendrik Andreas; Hermann, Robert Michael; Vorwerk, Hilke; Hille, Andrea; Christiansen, Hans [Dept. of Radiotherapy, Univ. of Goettingen (Germany); Roedel, Ralph; Steiner, Wolfgang [Dept. of Otorhinolaryngology, Univ. of Goettingen (Germany); Pradier, Olivier [Dept. of Cancerology, CHU Morvan, Brest (France)

    2009-05-15

    Background and purpose: transoral laser microsurgery (TLM) and adjuvant radiotherapy are an established therapy regimen for locally advanced laryngeal cancer at our institution. Aim of the present study was to assess value of quality of life (QoL) data with special regard to organ function under consideration of treatment efficacy in patients with locally advanced laryngeal cancer treated with larynx-preserving TLM and adjuvant radiotherapy. Patients and methods: from 1994 to 2006, 39 patients (ten UICC stage III, 29 UICC stage IVA/B) with locally advanced laryngeal carcinomas were treated with TLM and adjuvant radiotherapy. Data concerning treatment efficacy, QoL (using the VHI [Voice Handicap Index], the EORTC QLQ-C30 and QLQ-H and N35 questionnaires) and organ function (respiration, deglutition, voice quality) were obtained for ten patients still alive after long-term follow-up. Correlations were determined using the Spearman rank test. Results: after a median follow-up of 80.8 months, the 5-year overall survival rate was 46.8% and the locoregional control rate 76.5%, respectively. The larynx preservation rate was 89.7% for all patients and 100% for patients still alive after follow-up. Despite some verifiable problems in respiration, speech and swallowing, patients showed a subjectively good QoL. Conclusion: TLM and adjuvant radiotherapy is a curative option for patients with locally advanced laryngeal cancer and an alternative to radical surgery. Even if functional deficits are unavoidable in the treatment of locally advanced laryngeal carcinomas, larynx preservation is associated with a subjectively good QoL. (orig.)

  12. Studies of Flame Structure in Microgravity

    Science.gov (United States)

    Law, C. K.; Sung, C. J.; Zhu, D. L.

    1997-01-01

    The present research endeavor is concerned with gaining fundamental understanding of the configuration, structure, and dynamics of laminar premixed and diffusion flames under conditions of negligible effects of gravity. Of particular interest is the potential to establish and hence study the properties of spherically- and cylindrically-symmetric flames and their response to external forces not related to gravity. For example, in an earlier experimental study of the burner-stabilized cylindrical premixed flames, the possibility of flame stabilization through flow divergence was established, while the resulting one-dimensional, adiabatic, stretchless flame also allowed an accurate means of determining the laminar flame speeds of combustible mixtures. We have recently extended our studies of the flame structure in microgravity along the following directions: (1) Analysis of the dynamics of spherical premixed flames; (2) Analysis of the spreading of cylindrical diffusion flames; (3) Experimental observation of an interesting dual luminous zone structure of a steady-state, microbuoyancy, spherical diffusion flame of air burning in a hydrogen/methane mixture environment, and its subsequent quantification through computational simulation with detailed chemistry and transport; (4) Experimental quantification of the unsteady growth of a spherical diffusion flame; and (5) Computational simulation of stretched, diffusionally-imbalanced premixed flames near and beyond the conventional limits of flammability, and the substantiation of the concept of extended limits of flammability. Motivation and results of these investigations are individually discussed.

  13. Hysteresis and transition in swirling nonpremixed flames

    NARCIS (Netherlands)

    Tummers, M.J.; Hübner, A.W.; Veen, van E.H.; Hanjalic, K.; Meer, van der Th.H.

    2009-01-01

    Strongly swirling nonpremixed flames are known to exhibit a hysteresis when transiting from an attached long, sooty, yellow flame to a short lifted blue flame, and vice versa. The upward transition (by increasing the air and fuel flow rates) corresponds to a vortex breakdown, i.e. an abrupt change f

  14. Premixed flame propagation in vertical tubes

    Science.gov (United States)

    Kazakov, Kirill A.

    2016-04-01

    Analytical treatment of the premixed flame propagation in vertical tubes with smooth walls is given. Using the on-shell flame description, equations for a quasi-steady flame with a small but finite front thickness are obtained and solved numerically. It is found that near the limits of inflammability, solutions describing upward flame propagation come in pairs having close propagation speeds and that the effect of gravity is to reverse the burnt gas velocity profile generated by the flame. On the basis of these results, a theory of partial flame propagation driven by a strong gravitational field is developed. A complete explanation is given of the intricate observed behavior of limit flames, including dependence of the inflammability range on the size of the combustion domain, the large distances of partial flame propagation, and the progression of flame extinction. The role of the finite front-thickness effects is discussed in detail. Also, various mechanisms governing flame acceleration in smooth tubes are identified. Acceleration of methane-air flames in open tubes is shown to be a combined effect of the hydrostatic pressure difference produced by the ambient cold air and the difference of dynamic gas pressure at the tube ends. On the other hand, a strong spontaneous acceleration of the fast methane-oxygen flames at the initial stage of their evolution in open-closed tubes is conditioned by metastability of the quasi-steady propagation regimes. An extensive comparison of the obtained results with the experimental data is made.

  15. Experimental characterization of methane inverse diffusion flame

    KAUST Repository

    Elbaz, Ayman M.

    2014-06-26

    This article presents 10-kHz images of OH-PLIF simultaneously with 2-D PIV measurements in an inverse methane diffusion flame. Under a constant fuel flow rate, the central air jet Re was varied, leading to air to fuel velocity ratio, Vr, to vary from 8.3 to 66.5. Starting from Vr = 20.7, the flame is commonly characterized by three distinct zones. The length of the lower fuel entrainment region is inversely proportional to Vr. The flames investigated resemble a string shear layer confining this zone, and converging into the second distinct region, the flame neck zone. The third region is the rest of the flame, which spreads in a jet-like manner. The inverse diffusion flames exhibit varying degrees of partial premixing, depending upon on the velocity ratio Vr, and this region of partial premixing evolves into a well-mixed reaction zone along the flame centerline. The OH distribution correlated with the changes in the mean characteristics of the flow through reduction in the local Reynolds number due to heat release. The existence of a flame suppresses or laminarizes the turbulence at early axial locations and promotes fluctuations at the flame tip for flames with Vr < 49.8. In addition, the flame jet width can be correlated to the OH distribution. In upstream regions of the flames, the breaks in OH are counterbalanced by flame closures and are governed by edge flame propagation. These local extinctions were found to occur at locations where large flow structures were impinging on the flame and are associated with a locally higher strain rate or correlated to the local high strain rates at the flame hole edges without this flow impinging. Another contributor to re-ignition was found to be growing flame kernels. As the flames approach global blow-off, these kernels become the main mechanism for re-ignition further downstream of the flames. At low Vr, laminarization within the early regions of the flame provides an effective shield, preventing the jet flow from

  16. Direct Numerical Simulations of Statistically Stationary Turbulent Premixed Flames

    KAUST Repository

    Im, Hong G.

    2016-07-15

    Direct numerical simulations (DNS) of turbulent combustion have evolved tremendously in the past decades, thanks to the rapid advances in high performance computing technology. Today’s DNS is capable of incorporating detailed reaction mechanisms and transport properties of hydrocarbon fuels, with physical parameter ranges approaching laboratory scale flames, thereby allowing direct comparison and cross-validation against laser diagnostic measurements. While these developments have led to significantly improved understanding of fundamental turbulent flame characteristics, there are increasing demands to explore combustion regimes at higher levels of turbulent Reynolds (Re) and Karlovitz (Ka) numbers, with a practical interest in new combustion engines driving towards higher efficiencies and lower emissions. The article attempts to provide a brief overview of the state-of-the-art DNS of turbulent premixed flames at high Re/Ka conditions, with an emphasis on homogeneous and isotropic turbulent flow configurations. Some important qualitative findings from numerical studies are summarized, new analytical approaches to investigate intensely turbulent premixed flame dynamics are discussed, and topics for future research are suggested. © 2016 Taylor & Francis.

  17. Clinical observation on scores of anxiety, depression and quality of life for advanced gastrointestinal carcinoma patients with palliation intervention therapy

    International Nuclear Information System (INIS)

    Objective: To evaluate the influence of palliative intervention therapy on advanced gastrointestinal carcinoma patients with depression and anxiety before and after the treatment. Methods: 56 advanced gastrointestinal carcinoma patients were selected and treated with intra-arterial perfusion chemotherapy or intra-arterial perfusion chemotherapy with embolization. Curative effects were assessed with the SDS, SAS and FACT-G before and after the treatment. In addition, all patients took self-assessment with SCL-90, comparing with the Chinese norms. Results: SCL-90 scores including the somatization agent, depression agent, and anxiety agent scores of the advanced gastrointestinal carcinoma were higher than those of Chinese norms, with significant difference (P<0.05). After palliative intervention therapy, the scores of SDS and SAS were lower than those before the palliative intervention therapy with significant difference (P< 0.05); and furthermore with an obvious improvement in the scores of FACT-G (P<0.05). Conclusion: Palliative intervention therapy for advanced gastrointestinal carcinoma patients can improve the complaints of depression anxiety and quality of life. (authors)

  18. Patient, carer and professional perspectives on barriers and facilitators to quality care in advanced heart failure.

    Directory of Open Access Journals (Sweden)

    Susan Browne

    Full Text Available BACKGROUND: Those with advanced heart failure (HF experience high levels of morbidity and mortality, similar to common cancers. However, there remains evidence of inequity of access to palliative care services compared to people with cancer. This study examines patient, carer, and professional perspectives on current management of advanced HF and barriers and facilitators to improved care. METHODS: Qualitative study involving semi-structured interviews and focus groups with advanced HF patients (n = 30, carers (n = 20, and professionals (n = 65. Data analysed using Normalisation Process Theory (NPT as the underpinning conceptual framework. FINDINGS: Uncertainty is ubiquitous in accounts from advanced HF patients and their caregivers. This uncertainty relates to understanding of the implications of their diagnosis, appropriate treatments, and when and how to seek effective help. Health professionals agree this is a major problem but feel they lack knowledge, opportunities, or adequate support to improve the situation. Fragmented care with lack of coordination and poor communication makes life difficult. Poor understanding of the condition extends to the wider circle of carers and means that requests for help may not be perceived as legitimate, and those with advanced HF are not prioritised for social and financial supports. Patient and caregiver accounts of emergency care are uniformly poor. Managing polypharmacy and enduring concomitant side effects is a major burden, and the potential for rationalisation exists. This study has potential limitations because it was undertaken within a single geographical location within the United Kingdom. CONCLUSIONS: Little progress is being made to improve care experiences for those with advanced HF. Even in the terminal stages, patients and caregivers are heavily and unnecessarily burdened by health care services that are poorly coordinated and offer fragmented care. There is evidence that these poor

  19. Health-related Quality of Life after complex rectal surgery for primary advanced rectal cancer and locally recurrent rectal cancer

    DEFF Research Database (Denmark)

    Thaysen, Henriette Vind

    2013-01-01

    Advances in the treatment of rectal cancer, have made it possible to perform complex rectal cancer surgery (COMP-RCS) with curative intent in patients with primary advanced rectal caner (PARC) and local recurrent rectal cancer (LRRC). Due to the complexity of the treatment and its high...... postoperative morbidity, Health-related Quality of Life (HRQoL) is an important issue. The overall aim of this thesis was therefore to evaluate HRQoL in patients with PARC and LRRC treated with COMP-RCS and curative intent. In study I a review of the literature was undertaken to provide an overview of HRQo...... in the study was 164 (86%) patients treated with standard rectal cancer surgery (STAN-RCS). The Danish version showed satisfactory psychometric properties for the scales concerning body image, sexual functioning, male sexual problems and defecations problems. Reduced psychometric properties were found...

  20. The applicability of advanced treatment processes in the management of deteriorating water quality in the Mid-Vaal river system / Zelda Hudson

    OpenAIRE

    Hudson, Zelda

    2015-01-01

    The main objective of this study was to determine the applicability of advanced water treatment processes namely granular activated carbon (GAC) adsorption, ultraviolet (UV) light disinfectant and ozone in the management of deteriorating water quality in the Mid-Vaal River system for drinking purposes. Both the scarcity and the deteriorating quality of water in South Africa can be addressed by investigating advanced water treatment processes such as GAC adsorption, UV light disinfectant and o...

  1. Editorial: Advances in healthcare provider and patient training to improve the quality and safety of patient care

    Directory of Open Access Journals (Sweden)

    Elizabeth M. Borycki

    2015-09-01

    Full Text Available This special issue of the Knowledge Management & E-Learning: An International Journal is dedicated to describing “Advances in Healthcare Provider and Patient Training to Improve the Quality and Safety of Patient Care.” Patient safety is an important and fundamental requirement of ensuring the quality of patient care. Training and education has been identified as a key to improving healthcare provider patient safety competencies especially when working with new technologies such as electronic health records and mobile health applications. Such technologies can be harnessed to improve patient safety; however, if not used properly they can negatively impact on patient safety. In this issue we focus on advances in training that can improve patient safety and the optimal use of new technologies in healthcare. For example, use of clinical simulations and online computer based training can be employed both to facilitate learning about new clinical discoveries as well as to integrate technology into day to day healthcare practices. In this issue we are publishing papers that describe advances in healthcare provider and patient training to improve patient safety as it relates to the use of educational technologies, health information technology and on-line health resources. In addition, in the special issue we describe new approaches to training and patient safety including, online communities, clinical simulations, on-the-job training, computer based training and health information systems that educate about and support safer patient care in real-time (i.e. when health professionals are providing care to patients. These educational and technological initiatives can be aimed at health professionals (i.e. students and those who are currently working in the field. The outcomes of this work are significant as they lead to safer care for patients and their family members. The issue has both theoretical and applied papers that describe advances in patient

  2. Advancing the Value and Quality of Occupational Therapy in Health Service Delivery

    OpenAIRE

    Leland, Natalie E.; Crum, Karen; Phipps, Shawn; Roberts, Pamela; Gage, Barbara

    2014-01-01

    The authors set forth a foundation on which to build further dialogue and evidence to highlight occupational therapy’s distinctive contribution, significance, and viability as health care policies shift to focus on quality and value.

  3. Determinants of quality of life in advanced kidney disease: time to screen?

    Science.gov (United States)

    Iyasere, Osasuyi; Brown, Edwina A

    2014-06-01

    The incidence of older patients with end stage renal disease is on the increase. This group of patients have multiple comorbidities and a high symptom burden. Dialysis can be life sustaining for such patients. But it is often at the expense of quality of life, which starts to decline early in the pathway of chronic kidney disease. Quality of life is also important to patients and is a major determinant in decisions regarding renal replacement. As a result, validated patient-reported outcome measures are increasingly used to assess quality of life in renal patients. Cognitive impairment, depression, malnutrition and function decline are non-renal determinants of quality of life and mortality. They are under-recognised in the renal population but are potentially treatable, if not preventable. This review article discusses aetio-pathogenesis, prevalence and impact of these four outcomes, advocating regular screening for early identification and management.

  4. Flame monitoring enhances burner management

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, T.; Bailey, R.; Fuller, T.; Daw, S.; Finney, C.; Stallings, J. [Babcock & Wilcox Research Center (USA)

    2003-02-01

    A new burner monitoring and diagnostic system called Flame Doctor offers users a more precise and discriminating understanding of burner conditions. Alpha testing on Unit 4 at AmerenUE's Meramec power plant in St. Louis, MO, USA and Beta testing is underway at plants owned by Dynegy and Allegheny Energy. 6 refs., 3 figs.

  5. Olympic Flame Burning In Athens

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正>At 6:00pm March 25 (Beijing time), 2004 Athens Olympic flame was lit in Greece’s ancient sanctuary, indicating that the torch relay started.The torch relay, established at the Berlin Games in 1936, will for the first time visit all five continents

  6. The VLT FLAMES Tarantula Survey

    NARCIS (Netherlands)

    C. Evans; W. Taylor; H. Sana; V. Hénault-Brunet; T. Bagnoli; N. Bastian; J. Bestenlehner; A. Bonanos; E. Bressert; I. Brott; M. Campbell; M. Cantiello; G. Carraro; S. Clark; E. Costa; P. Crowther; A. de Koter; S. de Mink; E. Doran; P. Dufton; P. Dunstall; M. Garcia; M. Gieles; G. Gräfener; A. Herrero; I. Howarth; R. Izzard; K. Köhler; N. Langer; D. Lennon; J. Maíz Apellániz; N. Markova; P. Najarro; J. Puls; O. Ramirez; C. Sabín-Sanjulián; S. Simón-Díaz; S. Smartt; V. Stroud; J. van Loon; J.S. Vink; N. Walborn

    2011-01-01

    We introduce the VLT FLAMES Tarantula Survey, an ESO Large Programme from which we have obtained optical spectroscopy of over 800 massive stars in the spectacular 30 Doradus region of the Large Magellanic Cloud. A key feature is the use of multi-epoch observations to provide strong constraints on th

  7. Comparison of Quality Oncology Practice Initiative (QOPI) Measure Adherence Between Oncology Fellows, Advanced Practice Providers, and Attending Physicians.

    Science.gov (United States)

    Zhu, Jason; Zhang, Tian; Shah, Radhika; Kamal, Arif H; Kelley, Michael J

    2015-12-01

    Quality improvement measures are uniformly applied to all oncology providers, regardless of their roles. Little is known about differences in adherence to these measures between oncology fellows, advance practice providers (APP), and attending physicians. We investigated conformance across Quality Oncology Practice Initiative (QOPI) measures for oncology fellows, advance practice providers, and attending physicians at the Durham Veterans Affairs Medical Center (DVAMC). Using data collected from the Spring 2012 and 2013 QOPI cycles, we abstracted charts of patients and separated them based on their primary provider. Descriptive statistics and the chi-square test were calculated for each QOPI measure between fellows, advanced practice providers (APPs), and attending physicians. A total of 169 patients were reviewed. Of these, 31 patients had a fellow, 39 had an APP, and 99 had an attending as their primary oncology provider. Fellows and attending physicians performed similarly on 90 of 94 QOPI metrics. High-performing metrics included several core QOPI measures including documenting consent for chemotherapy, recommending adjuvant chemotherapy when appropriate, and prescribing serotonin antagonists when prescribing emetogenic chemotherapies. Low-performing metrics included documentation of treatment summary and taking action to address problems with emotional well-being by the second office visit. Attendings documented the plan for oral chemotherapy more often (92 vs. 63%, P=0.049). However, after the chart audit, we found that fellows actually documented the plan for oral chemotherapy 88% of the time (p=0.73). APPs and attendings performed similarly on 88 of 90 QOPI measures. The quality of oncology care tends to be similar between attendings and fellows overall; some of the significant differences do not remain significant after a second manual chart review, highlighting that the use of manual data collection for QOPI analysis is an imperfect system, and there may

  8. Methods for assessing quality characteristics of non-grain starch staples. (Part 4. Advanced methods.)

    OpenAIRE

    Bainbridge, Z.; Tomlins, K.; Wellings, K; Westby, A.

    1996-01-01

    This manual sets out in a four-part publication the main methods necessary to evaluate the quality characteristics of nongrain starch staple (NGSS) food crops (cassava, sweet potato, banana, plantain, yam and cocoyam) and their processed products. It is designed to be a reference source and laboratory guide for food analysis laboratories and those concerned with the quality of NGSS. It is hoped that the provision of this manual and its active promotion through workshops will assist in the upt...

  9. Enhancements of Impinging Flame by Pulsation

    Institute of Scientific and Technical Information of China (English)

    AySu; Ying-ChiehLiu

    2000-01-01

    Experimental investigations on the pulsating jet-impinging diffusion flame were executed.A soleoid valve was aligned upstream of the jet orifice and the methane fuel was controlled in open-closed cycles from 0 Hz to 20Hz.Results show that the open-closed cycles,indeed increase the fluctuations of the methane fuel obviously.The evolutions of pulsating flame therefore develop faster than the continuous impinging flame.The optimized pulating frequencies are near 9 to 11 hz from the Re=170 to 283.The temperature differences between that under optimized pulsating rate and full open condition(no pulsation)are ranging from 100 to 150 degree.The pulsating effect is more singnificant at low Reynolds number.The cross section of continuous impinging flame behaves as elliptic shape with axial ratio equals to 2/3.The tip of the impinging flame obviously crosses at 42mm above the impinging point.ecause of the phenomenon of pulsation flame,the flame sheet or flame front may not be identified clearly in the averaged temperature contours.Results shows that the averaged end-contour of pulsation flame rears at 38mm above the impinging point.By observation and experiment,the pulsating flame behaves more stable and efficient than the continuous impinging flame.

  10. Improvements of natural rubber for flame resistance

    Directory of Open Access Journals (Sweden)

    Orasa Patarapaiboolchai

    2010-07-01

    Full Text Available The present invention provides a process for treating natural rubber to increase its flame retardant capability. Theprocess comprises a mixture of a natural rubber with, (a halogenated free flame retardant agent (zinc hydroxystannate;STORFLAM ZHS and (b halogenated flame retardant agent (decabromodiphenyl; Great Lake DE-83R and chlorinatedparaffins; Plastoil 152 and another material like antimony trioxide and aluminium hydroxide in appropriate amount, with ratio of halogenated flame retardant agent: antimony trioxide 3:1. In the resulting product with halogen flame retardant showed a more efficient flame retardant property than halogen free flame retardant, i.e. brominated flame retardant provide higher efficiency than chlorinated and ZHS, respectively. The minimum requirement ratio for being flame retardant of antimonytrioxide: brominated or chlorinated agent is 7:21 or 10:30 phr while aluminium hydroxide: ZHS is 10: 150 phr. It was found thatburning rate was zero for brominated and chlorinated agent used but not for zinc hydroxyl stannate system. Average time of burning (ATB was 135, 118 and 41 second for brominated, chlorinated and ZHS flame retardant, respectively. Average extent of burning (AEB was 24, 19 and 14 millimeters, respectively. An advantage of this invention is that chemicals (antimony trioxide and either brominated or chlorinated agent added to natural rubber have the effect of rendering the natural rubber flame-resistant like synthetic rubbers, chloroprene.

  11. Studies on fibre quality of a long staple cotton variety using high volume instrument and advanced fibre information system for fibre quality improvement

    Directory of Open Access Journals (Sweden)

    S Manickam and S Venkatakrishnan

    2014-06-01

    Full Text Available Fibre quality parameters of 20 plants of a long staple cotton variety Suraj were analyzed using High Volume Instrument (HVI and Advanced Fibre Information System (AFIS and were compared. From AFIS data, narrow range of coefficient of variability (of less than 10 % was noticed in characters like length (by weight, upper quartile length (by weight, length (by number, 5 % length (by number, fineness (mtex, maturity ratio and fibre neps. Comparatively larger extent of variability was noticed (of more than 10 % for short fibre content (both by weight and by number, immature fibre content, fibre neps – count/g, seed coat neps – count/g and for seed coat neps – mean size. However, the coefficient of variability for 2.5 % span length (mm, uniformity ratio (%, micronaire (μg/inch and tenacity at 3.2 mm gauge (g/tex was low when the fibre quality data was generated in HVI. This shows that variability estimates were narrow in the selected plants when fibre quality was analysed in HVI and exposes inherent weakness in analysing the fibre quality with HVI in breeders’ perspective. Correlation coefficients between immature fibre content and short fibre content, both by number (r = 0.89 and by weight (r = 0.84 were very high indicating that by reducing short fibre content the immature fibre content can be reduced drastically. Further, the correlation between immature fibre content and tenacity at 3.2 mm gauge was negative and was high (-0.91. Plants with ideal combination of yield and fibre quality parameters were identified for further exploitation.

  12. Flame Reconstruction Using Synthetic Aperture Imaging

    CERN Document Server

    Murray, Preston; Tree, Dale; Truscott, Tadd

    2011-01-01

    Flames can be formed by burning methane (CH4). When oxygen is scarce, carbon particles nucleate into solid particles called soot. These particles emit photons, making the flame yellow. Later, methane is pre-mixed with air forming a blue flame; burning more efficiently, providing less soot and light. Imaging flames and knowing their temperature are vital to maximizing efficiency and validating numerical models. Most temperature probes disrupt the flame and create differences leading to an inaccurate measurement of the flame temperature. We seek to image the flame in three dimensions using synthetic aperture imaging. This technique has already successfully measured velocity fields of a vortex ring [1]. Synthetic aperture imaging is a technique that views one scene from multiple cameras set at different angles, allowing some cameras to view objects that are obscured by others. As the resulting images are overlapped different depths of the scene come into and out of focus, known as focal planes, similar to tomogr...

  13. Turbulent Jet Flames Into a Vitiated Coflow. PhD Thesis awarded Spring 2003

    Science.gov (United States)

    Holdeman, James D. (Technical Monitor); Cabra, Ricardo

    2004-01-01

    Examined is the vitiated coflow flame, an experimental condition that decouples the combustion processes of flows found in practical combustors from the associated recirculating fluid mechanics. The configuration consists of a 4.57 mm diameter fuel jet into a coaxial flow of hot combustion products from a lean premixed flame. The 210 mm diameter coflow isolates the jet flame from the cool ambient, providing a hot environment similar to the operating conditions of advanced combustors; this important high temperature element is lacking in the traditional laboratory experiments of jet flames into cool (room) air. A family of flows of increasing complexity is presented: 1) nonreacting flow, 2) all hydrogen flame (fuel jet and premixed coflow), and 3) set of methane flames. This sequence of experiments provides a convenient ordering of validation data for combustion models. Laser Raman-Rayleigh-LIF diagnostics at the Turbulent Diffusion Flame laboratory of Sandia National Laboratories produced instantaneous multiscalar point measurements. These results attest to the attractive features of the vitiated coflow burner and the well-defined boundary conditions provided by the coflow. The coflow is uniform and steady, isolating the jet flame from the laboratory air for a downstream distance ranging from z/d = 50-70. The statistical results show that differential diffusion effects in this highly turbulent flow are negligible. Complementing the comprehensive set of multiscalar measurements is a parametric study of lifted methane flames that was conducted to analyze flame sensitivity to jet and coflow velocity, as well as coflow temperature. The linear relationship found between the lift-off height and the jet velocity is consistent with previous experiments. New linear sensitivities were found correlating the lift-off height to coflow velocity and temperature. A blow-off study revealed that the methane flame blows off at a common coflow temperature (1260 K), regardless of

  14. CFD simulation of vented explosion and turbulent flame propagation

    Directory of Open Access Journals (Sweden)

    Tulach Aleš

    2015-01-01

    Full Text Available Very rapid physical and chemical processes during the explosion require both quality and quantity of detection devices. CFD numerical simulations are suitable instruments for more detailed determination of explosion parameters. The paper deals with mathematical modelling of vented explosion and turbulent flame spread with use of ANSYS Fluent software. The paper is focused on verification of preciseness of calculations comparing calculated data with the results obtained in realised experiments in the explosion chamber.

  15. CFD simulation of vented explosion and turbulent flame propagation

    OpenAIRE

    Tulach Aleš; Mynarz Miroslav; Kozubková Milada

    2015-01-01

    Very rapid physical and chemical processes during the explosion require both quality and quantity of detection devices. CFD numerical simulations are suitable instruments for more detailed determination of explosion parameters. The paper deals with mathematical modelling of vented explosion and turbulent flame spread with use of ANSYS Fluent software. The paper is focused on verification of preciseness of calculations comparing calculated data with the results obtained in realised experiments...

  16. CFD simulation of vented explosion and turbulent flame propagation

    Science.gov (United States)

    Tulach, Aleš; Mynarz, Miroslav; Kozubková, Milada

    2015-05-01

    Very rapid physical and chemical processes during the explosion require both quality and quantity of detection devices. CFD numerical simulations are suitable instruments for more detailed determination of explosion parameters. The paper deals with mathematical modelling of vented explosion and turbulent flame spread with use of ANSYS Fluent software. The paper is focused on verification of preciseness of calculations comparing calculated data with the results obtained in realised experiments in the explosion chamber.

  17. A flame particle tracking analysis of turbulence–chemistry interaction in hydrogen–air premixed flames

    KAUST Repository

    Uranakara, Harshavardhana A.

    2015-11-21

    Interactions of turbulence, molecular transport, and energy transport, coupled with chemistry play a crucial role in the evolution of flame surface geometry, propagation, annihilation, and local extinction/re-ignition characteristics of intensely turbulent premixed flames. This study seeks to understand how these interactions affect flame surface annihilation of lean hydrogen–air premixed turbulent flames. Direct numerical simulations (DNSs) are conducted at different parametric conditions with a detailed reaction mechanism and transport properties for hydrogen–air flames. Flame particle tracking (FPT) technique is used to follow specific flame surface segments. An analytical expression for the local displacement flame speed (Sd) of a temperature isosurface is considered, and the contributions of transport, chemistry, and kinematics on the displacement flame speed at different turbulence-flame interaction conditions are identified. In general, the displacement flame speed for the flame particles is found to increase with time for all conditions considered. This is because, eventually all flame surfaces and their resident flame particles approach annihilation by reactant island formation at the end of stretching and folding processes induced by turbulence. Statistics of principal curvature evolving in time, obtained using FPT, suggest that these islands are ellipsoidal on average enclosing fresh reactants. Further examinations show that the increase in Sd is caused by the increased negative curvature of the flame surface and eventual homogenization of temperature gradients as these reactant islands shrink due to flame propagation and turbulent mixing. Finally, the evolution of the normalized, averaged, displacement flame speed vs. stretch Karlovitz number are found to collapse on a narrow band, suggesting that a unified description of flame speed dependence on stretch rate may be possible in the Lagrangian description.

  18. Modelling thermal radiation and soot formation in buoyant diffusion flames

    International Nuclear Information System (INIS)

    The radiative heat transfer plays an important role in fire problems since it is the dominant mode of heat transfer between flames and surroundings. It controls the pyrolysis, and therefore the heat release rate, and the growth rate of the fire. In the present work a numerical study of buoyant diffusion flames is carried out, with the main objective of modelling the thermal radiative transfer and the soot formation/destruction processes. In a first step, different radiative property models were tested in benchmark configurations. It was found that the FSCK coupled with the Modest and Riazzi mixing scheme was the best compromise in terms of accuracy and computational requirements, and was a good candidate to be implemented in CFD codes dealing with fire problems. In a second step, a semi-empirical soot model, considering acetylene and benzene as precursor species for soot nucleation, was validated in laminar co flow diffusion flames over a wide range of hydrocarbons (C1-C3) and conditions. In addition, the optically-thin approximation was found to produce large discrepancies in the upper part of these small laminar flames. Reliable predictions of soot volume fractions require the use of an advanced radiation model. Then the FSCK and the semi-empirical soot model were applied to simulate laboratory-scale and intermediate-scale pool fires of methane and propane. Predicted flame structures as well as the radiant heat flux transferred to the surroundings were found to be in good agreement with the available experimental data. Finally, the interaction between radiation and turbulence was quantified. (author)

  19. Advanced Water Quality Modelling in Marine Systems: Application to the Wadden Sea, the Netherlands

    Science.gov (United States)

    Boon, J.; Smits, J. G.

    2006-12-01

    There is an increasing demand for knowledge and models that arise from water management in relation to water quality, sediment quality (ecology) and sediment accumulation (ecomorphology). Recently, models for sediment diagenesis and erosion developed or incorporated by Delft Hydraulics integrates the relevant physical, (bio)chemical and biological processes for the sediment-water exchange of substances. The aim of the diagenesis models is the prediction of both sediment quality and the return fluxes of substances such as nutrients and micropollutants to the overlying water. The resulting so-called DELWAQ-G model is a new, generic version of the water and sediment quality model of the DELFT3D framework. One set of generic water quality process formulations is used to calculate process rates in both water and sediment compartments. DELWAQ-G involves the explicit simulation of sediment layers in the water quality model with state-of-the-art process kinetics. The local conditions in a water layer or sediment layer such as the dissolved oxygen concentration determine if and how individual processes come to expression. New processes were added for sulphate, sulphide, methane and the distribution of the electron-acceptor demand over dissolved oxygen, nitrate, sulphate and carbon dioxide. DELWAQ-G also includes the dispersive and advective transport processes in the sediment and across the sediment-water interface. DELWAQ-G has been applied for the Wadden Sea. A very dynamic tidal and ecologically active estuary with a complex hydrodynamic behaviour located at the north of the Netherlands. The predicted profiles in the sediment reflect the typical interactions of diagenesis processes.

  20. Palliative Care Improves Survival, Quality of Life in Advanced Lung Cancer | Division of Cancer Prevention

    Science.gov (United States)

    Results from the first randomized clinical trial of its kind have revealed a surprising and welcome benefit of early palliative care for patients with advanced lung cancer—longer median survival. Although several researchers said that the finding needs to be confirmed in other trials of patients with other cancer types, they were cautiously optimistic that the trial results could influence oncologists’ perceptions and use of palliative care. |

  1. Prospective clinical study on long-term swallowing function and voice quality in advanced head and neck cancer patients treated with concurrent chemoradiotherapy and preventive swallowing exercises

    NARCIS (Netherlands)

    S.A.C. Kraaijenga; L. van der Molen; I. Jacobi; O. Hamming-Vrieze; F.J.M. Hilgers; M.W.M. van den Brekel

    2014-01-01

    Concurrent chemoradiotherapy (CCRT) for advanced head and neck cancer (HNC) is associated with substantial early and late side effects, most notably regarding swallowing function, but also regarding voice quality and quality of life (QoL). Despite increased awareness/knowledge on acute dysphagia in

  2. Quality of life of patients with locally advanced rectal cancer: anterior rectal resection with colorectal anastomosis versus abdominoperineal excision

    Directory of Open Access Journals (Sweden)

    Maria-Gabriela Aniţei

    2013-09-01

    Full Text Available BACKGROUND: Despite advances in neoadjuvant treatment, rectal resection remains the gold-standard treatment for rectal cancer. AIM: The aim of this study was to assess the benefits of anal sphincter preservation and to compare the quality of life in terms of functional outcome in long term survivors who underwent low (or ultra low anterior resection with total mesorectal excision to patients with abdominoperineal excision for locally advanced rectal cancer with neoadjuvant therapy. MATERIAL AND METHODS: We retrospectively analyzed the medical records of 319 patients who underwent surgery for rectal cancer from 2006 to 2011. Quality of life in 69 eligible patients with preoperative treatment and rectal resection with total mesorectal excision was assessed using the EORTC QLQ C 30 and EORTC QLQ CR29 questionnaires. We evaluated the overall status of quality of life and functional status of these patients symptoms scale. High score for functional scores shows better function whereas high symptom score shows more problems. Results were compared for patients with anal sphincter preservation (SP, 20 patients versus abdominoperineal excision (APE, 49 patients using t-Student test for independent samples. RESULTS: The median follow up in 69 patients was 32 months (range 11-74 months, 32±2,3SD. Quality of life for our group is significantly higher than the reference EORTC population (P < 0.001. Physical functioning (P = 0.050, cognitive functioning (P = 0.039, emotional functioning (P = 0.006, physical and social functioning (P = 0.005, constipation (P = 0.018, body image (P = 0.003, abdominal pain (P = 0.004, embarrassment (P = 0.003 were significantly better for patients with SP. There was no significant differences in the general symptoms of the radiochemotherapy treatment (mouth dryness, hair loss, flavor. Most of the symptom scales like sexual interest, impotence, dyspareunia, diarrhoea did not differ. APE patients suffered more from anxiety (P = 0

  3. Quality of life after hyperthermic isolated limb perfusion for locally advanced extremity soft tissue sarcoma

    NARCIS (Netherlands)

    Thijssens, KMJ; Hoekstra-Weebers, JEHM; van Ginkel, RJ; Hoekstra, HJ

    2006-01-01

    Background: Quality of life (QoL) and posttraumatic stress symptoms (PTSS) were studied in patients with soft tissue sarcoma (STS) of the extremities treated with isolated limb perfusion and delayed resection, with or without adjuvant irradiation. Methods: Forty-one patients received a questionnaire

  4. Effects of Buoyancy on Lean Premixed V-Flames Part I: Laminar and Turblent Flame Structure

    Science.gov (United States)

    Cheng, Robert K.; Bedat, Benoit; Kostiuk, Larry W.

    1998-01-01

    Laser schlieren and planar laser-induced fluorescence techniques have been used to investigate laminar and turbulent v-flames in +g, -g, and micro g under flow conditions that span the regimes of momentum domination (Ri buoyancy domination (Ri > 0.1). Overall flame features shown by schlieren indicate that buoyancy dominates the entire flow field for conditions close to Ri = 1. With decreasing Ri, buoyancy effects are observed only in the far-field regions. Analyses of the mean flame angles demonstrate that laminar and turbulent flames do not have similar responses to buoyancy. Difference in the laminar +g and -g flame angles decrease with Ri (i.e., increasing Re) and converge to the microgravity flame angle at the momentum limit (Ri - 0). This is consistent with the notion that the effects of buoyancy diminish with increasing flow momentum. The +g and -g turbulent flame angles, however, do not converge at Ri = 0. As shown by OH-PLIF images, the inconsistency in +g and -g turbulent flame angles is associated with the differences in flame wrinkles. Turbulent flame wrinkles evolve more slowly in +g than in -g. The difference in flame wrinkle structures, however, cannot be explained in terms of buoyancy effects on flame instability mechanisms. It seems to be associated with the field effects of buoyancy that stretches the turbulent flame brushes in +g and compresses the flame brush in -g. Flame wrinkling offers a mechanism through which the flame responds to the field effects of buoyancy despite increasing flow momentum. These observations point to the need to include both upstream and downstream contributions in theoretical analysis of flame turbulence interactions.

  5. Flame Propagation Through Concentration Gradient

    Institute of Scientific and Technical Information of China (English)

    JunyaIINO; MitsuakiTANABE; 等

    2000-01-01

    The experiment was carried out in homogeneous propane-air mixture and in several concentration gradient of mixture.Igniter is put on the upper side of the combustion chamber,In concentration gradient experiment.ixture was ignited from lean side.An experimental study was conducted in a combustion chamber.The combustion chamber has glass windows for optical measurements at any side.For the measurement of distribution of fuel concentration,infraed absorption method using 3.39μm He-Ne laser was used,and for the observation of proagating flams,Schlieren method was employed.As a measurment result of flame propagation velocity and flammable limit,for a mixture of an identical local equivalence ratio.flame propagation velocity in concentration gradient is faster than that in homogeneous mixture,and rich flammable limit in concentration gradient shows a tendency to be higher than that in homogeneous mixture.

  6. [Advances in psychosocial interventions on quality of life of cancer survivors].

    Science.gov (United States)

    Chen, Xuefen; Wang, Jiwei; Gong, Xiaohuan; Yu, Jinming

    2015-02-01

    In recent years, there has been increasing recognition of the importance of psychosocial interventions' studies on quality of life in cancer survivors because of improving cancer survival rate. This paper was an integrative literatures review of various psychosocial interventions including cognitive behavioral therapy, group-based supportive therapy, counseling or psychotherapy, education or psychoeducation and music therapy et al, and analyzing the complexity of psychosocial interventions' RCTs in oncology and the current characteristic of these studies in China. PMID:26081409

  7. Numerical study of effects of the intermediates and initial conditions on flame propagation in a real homogeneous charge compression ignition engine

    Directory of Open Access Journals (Sweden)

    Zhang Meng

    2014-01-01

    Full Text Available The premixed flame speed under a small four stock homogeneous charge compression ignition engine, fueled with dimethyl ether, was investigated. The effects of intermediate species, initial temperature, initial pressure, exhaust gas recirculation, and equivalence ratio were studied and compared to the baseline condition. Results show that, under all conditions, the flame speeds calculated without intermediates are higher than those which took the intermediates in consideration. Flame speeds increase with the increase of crank angle. The increase rate is divided into three regions and the increase rate is obviously high in the event of low temperature heat release. Initial temperature and pressure only affect the crank angle of flame speed, but have little influence on its value. Equivalence ratio and exhaust gas recirculation ratio do not only distinctly decrease the flame speed, but also advance the crank angle of flame speed.

  8. Chemical drinking water quality in Ghana: Water costs and scope for advanced treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rossiter, Helfrid M.A. [School of Engineering, The University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom); Owusu, Peter A.; Awuah, Esi [Department of Civil Engineering, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana); MacDonald, Alan M. [British Geological Survey, Murchison House, West Mains Road, Edinburgh, EH9 3LA (United Kingdom); Schaefer, Andrea I., E-mail: Andrea.Schaefer@ed.ac.uk [School of Engineering, The University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)

    2010-05-01

    To reduce child mortality and improve health in Ghana boreholes and wells are being installed across the country by the private sector, NGO's and the Ghanaian government. Water quality is not generally monitored once a water source has been improved. Water supplies were sampled across Ghana from mostly boreholes, wells and rivers as well as some piped water from the different regions and analysed for the chemical quality. Chemical water quality was found to exceed the WHO guidelines in 38% of samples, while pH varied from 3.7 to 8.9. Excess levels of nitrate (NO{sub 3}{sup -}) were found in 21% of the samples, manganese (Mn) and fluoride (F{sup -}) in 11% and 6.7%, respectively. Heavy metals such as lead (Pb), arsenic (As) and uranium (U) were localised to mining areas. Elements without health based guideline values such as aluminium (Al, 95%) and chloride (Cl, 5.7%) were found above the provisional guideline value. Economic information was gathered to identify water costs and ability to pay. Capital costs of wells and boreholes are about Pounds 1200 and Pounds 3800 respectively. The majority of installation costs are generally paid by the government or NGO's, while the maintenance is expected to be covered by the community. At least 58% of the communities had a water payment system in place, either an annual fee/one-off fee or 'pay-as-you-fetch'. The annual fee was between Pounds 0.3-21, while the boreholes had a water collection fee of Pounds 0.07-0.7/m{sup 3}, many wells were free. Interestingly, the most expensive water ( Pounds 2.9-3.5/m{sup 3}) was brought by truck. Many groundwater sources were not used due to poor chemical water quality. Considering the cost of unsuccessful borehole development, the potential for integrating suitable water treatment into the capital and maintenance costs of water sources is discussed. Additionally, many sources were not in use due to lack of water capacity, equipment malfunction or lack of economic

  9. Extinction of corrugated hydrogen/air flames

    International Nuclear Information System (INIS)

    Recent studies on flammability limits reveal the importance of flow nonuniformity, flame curvature, and molecular and thermal diffusivities in determining the extinguishability and the associated limits of premixed fuel/air flames. In particular, it is found that conditions which favor extinction of a lean flame may cause intensification of a rich flame. In the present study the authors have experimentally determined the extinction characteristics and limits of highly curved hydrogen/air flames as represented by the opening of bunsen flame tips. Results show that the tip opens at a constant fuel equivalence ratio of phi = 1.15, regardless of the velocity and uniformity of the upstream flow. This critical mixture concentration, while being rich, is still on the lean side of that corresponding to the maximum burning velocity (phi = 1.8), implying that for highly diffusive systems, the relevant reference concentration is that for maximum burning velocity instead of stoichiometry

  10. BALANCED SCORECARD AS AN ADVANCED MANAGEMENT CONCEPT WITHIN THE INTEGRATED QUALITY MANAGEMENT MODEL

    Directory of Open Access Journals (Sweden)

    Stevan Zivojinovic

    2008-03-01

    Full Text Available The significance of >Integratedquality management< (IQM model, originating form St.Gallen-model, is reflected in the need for synergic application of new and advanced concepts of management theory and practise. Balanced score card (BSC within IQM model becomes a catalyst of business success for a modern organization by focusing on organizational variables-business strategy, organization structure and corporate culture. BSC is the leading system of performance tracking and strategy implementation, consistent with other management concepts and methods for managing process improvement. Through BSC, IQM processes' activities correlate with organization business results. BSC management processes enable integration of all decision-making levels, from institutional via strategic to operative, in the process starting from planing, i.e. formulating and implementation of strategy, to feed back by performance measurement and control.

  11. In-flight Quality and Accuracy of Attitude Measurements from the CHAMP Advanced Stellar Compass

    DEFF Research Database (Denmark)

    Jørgensen, Peter Siegbjørn; Jørgensen, John Leif; Denver, Troelz;

    2005-01-01

    The German geo-observations satellite CHAMP carries highly accurate vector instruments. The orientation of these relative to the inertial reference frame is obtained using star trackers. These advanced stellar compasses (ASC) are fully autonomous units, which provide, in real time, the absolute...... attitude with accuracy in the arc second range. In order to investigate the in-flight accuracy of the ASC, the terminology to characterize noise and biases is introduced. Relative instrument accuracy (RIA) and absolute instrument accuracy (AIA) can in principle be determined in-flight. However problems...... with modeling external noise sources often arise. The special CHAMP configuration with two star tracker cameras mounted fixed together provides an excellent opportunity to determine the AIA in-flight using the inter boresight angle....

  12. Pole solutions for flame front propagation

    CERN Document Server

    Kupervasser, Oleg

    2015-01-01

    This book deals with solving mathematically the unsteady flame propagation equations. New original mathematical methods for solving complex non-linear equations and investigating their properties are presented. Pole solutions for flame front propagation are developed. Premixed flames and filtration combustion have remarkable properties: the complex nonlinear integro-differential equations for these problems have exact analytical solutions described by the motion of poles in a complex plane. Instead of complex equations, a finite set of ordinary differential equations is applied. These solutions help to investigate analytically and numerically properties of the flame front propagation equations.

  13. Quality

    International Nuclear Information System (INIS)

    What is quality? How do you achieve it? How do you keep it once you have got it. The answer for industry at large is the three-step hierarchy of quality control, quality assurance and Total quality Management. An overview is given of the history of quality movement, illustrated with examples from Schlumberger operations, as well as the oil industry's approach to quality. An introduction of the Schlumberger's quality-associated ClientLink program is presented. 15 figs., 4 ills., 16 refs

  14. Advances in the meta-analysis of heterogeneous clinical trials II: The quality effects model.

    Science.gov (United States)

    Doi, Suhail A R; Barendregt, Jan J; Khan, Shahjahan; Thalib, Lukman; Williams, Gail M

    2015-11-01

    This article examines the performance of the updated quality effects (QE) estimator for meta-analysis of heterogeneous studies. It is shown that this approach leads to a decreased mean squared error (MSE) of the estimator while maintaining the nominal level of coverage probability of the confidence interval. Extensive simulation studies confirm that this approach leads to the maintenance of the correct coverage probability of the confidence interval, regardless of the level of heterogeneity, as well as a lower observed variance compared to the random effects (RE) model. The QE model is robust to subjectivity in quality assessment down to completely random entry, in which case its MSE equals that of the RE estimator. When the proposed QE method is applied to a meta-analysis of magnesium for myocardial infarction data, the pooled mortality odds ratio (OR) becomes 0.81 (95% CI 0.61-1.08) which favors the larger studies but also reflects the increased uncertainty around the pooled estimate. In comparison, under the RE model, the pooled mortality OR is 0.71 (95% CI 0.57-0.89) which is less conservative than that of the QE results. The new estimation method has been implemented into the free meta-analysis software MetaXL which allows comparison of alternative estimators and can be downloaded from www.epigear.com.

  15. Advances in a study of sky quality for astronomical observations in Colombia

    Science.gov (United States)

    González-Díaz, D.; Pinzón, G.

    2015-10-01

    The aim of this study is to determine the sky quality in Colombia for astronomical observations in the optic. About 10,000 images in infrared (6.7 mu m and 10.7 mu m) were analyzed from the GOES meteorological satellites in three night times taken during a period of five years (2008 to 2014). A novel methodology was followed to determine how clear or covered was the sky in a given image. Meteorological data also were used from the weather stations network of the national meteorological institute, IDEAM. A correlation between threshold temperature and altitude was found for a historical data series of about 30 years. The results of the average percentage of nights with clear skies per year or clear sky fraction (CSF) were validated with the reports on the number of hours of astronomical observation from the logbooks of Llano del Hato Observatory in Merida-Venezuela, obtaining a cumulative percentage difference during the five years less than 10%. Annual cloud covering was computed over the whole country and it was classified the nights as clear or usable based on the definition of a quality factor.

  16. Content and quality of websites supporting self-management of chronic breathlessness in advanced illness: a systematic review.

    Science.gov (United States)

    Luckett, Tim; Disler, Rebecca; Hosie, Annmarie; Johnson, Miriam; Davidson, Patricia; Currow, David; Sumah, Anthony; Phillips, Jane

    2016-01-01

    Chronic breathlessness is a common, burdensome and distressing symptom in many advanced chronic illnesses. Self-management strategies are essential to optimise treatment, daily functioning and emotional coping. People with chronic illness commonly search the internet for advice on self-management. A review was undertaken in June 2015 to describe the content and quality of online advice on breathlessness self-management, to highlight under-served areas and to identify any unsafe content. Google was searched from Sydney, Australia, using the five most common search terms for breathlessness identified by Google Trends. We also hand-searched the websites of national associations. Websites were included if they were freely available in English and provided practical advice on self-management. Website quality was assessed using the American Medical Association Benchmarks. Readability was assessed using the Flesch-Kincaid grades, with grade 8 considered the maximum acceptable for enabling access. Ninety-one web pages from 44 websites met the inclusion criteria, including 14 national association websites not returned by Google searches. Most websites were generated in the USA (n=28, 64%) and focused on breathing techniques (n=38, 86%) and chronic obstructive pulmonary disease (n=27, 61%). No websites were found to offer unsafe advice. Adherence to quality benchmarks ranged from 9% for disclosure to 77% for currency. Fifteen (54%) of 28 written websites required grade ⩾9 reading level. Future development should focus on advice and tools to support goal setting, problem solving and monitoring of breathlessness. National associations are encouraged to improve website visibility and comply with standards for quality and readability. PMID:27225898

  17. Quality of life assessment in advanced cancer patients treated at home, an inpatient unit, and a day care center

    Directory of Open Access Journals (Sweden)

    Leppert W

    2014-05-01

    Full Text Available Wojciech Leppert,1 Mikolaj Majkowicz,2 Maria Forycka,1 Eleonora Mess,3 Agata Zdun-Ryzewska2 1Department of Palliative Medicine, Poznan University of Medical Sciences, Poznan, Poland; 2Department of Quality of Life Research, Gdansk Medical University, Gdansk, Poland; 3Palliative Care Nursing Department, Wroclaw Medical University, Wroclaw, Poland Aim of the study: To assess quality of life (QoL in cancer patients treated at home, at an in-patient palliative care unit (PCU, and at a day care center (DCC. Patients and methods: QoL was assessed in advanced cancer patients at baseline and after 7 days of symptomatic treatment using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 15-Palliative Care (EORTC QLQ-C15-PAL, the Edmonton Symptom Assessment System (ESAS, and the Karnofsky Performance Status (KPS scale. Results: A total of 129 patients completed the study, with 51 patients treated at home, 51 patients treated at the PCU, and 27 patients at DCC. In the EORTC QLQ-C15-PAL, improvement in functional and symptom scales was observed except in physical functioning and fatigue levels; patients at DCC had a better physical functioning, global QoL, appetite, and fatigue levels. In the ESAS, improvement in all items was found except for drowsiness levels, which was stable in patients treated at DCC and deteriorated in home and PCU patients. Higher activity, better appetite and well-being, and less drowsiness were observed in patients treated at DCC. KPS was better in DCC patients compared to those treated at home and at the PCU; the latter group deteriorated. Conclusions: QoL improved in all patient groups, with better results in DCC patients and similar scores in those staying at home and at the PCU. Along with clinical assessment, baseline age, KPS, physical and emotional functioning may be considered when assigning patients to care at a DCC, PCU, or at home. Keywords: oncology, patient care

  18. Assessing the quality of a deliberative democracy mini-public event about advanced biofuel production and development in Canada.

    Science.gov (United States)

    Longstaff, Holly; Secko, David M

    2016-02-01

    The importance of evaluating deliberative public engagement events is well recognized, but such activities are rarely conducted for a variety of theoretical, political and practical reasons. In this article, we provide an assessment of the criteria presented in the 2008 National Research Council report on Public Participation in Environmental Assessment and Decision Making (NRC report) as explicit indicators of quality for the 2012 'Advanced Biofuels' deliberative democracy event. The National Research Council's criteria were selected to evaluate this event because they are decision oriented, are the products of an exhaustive review of similar past events, are intended specifically for environmental processes and encompass many of the criteria presented in other evaluation frameworks. It is our hope that the results of our study may encourage others to employ and assess the National Research Council's criteria as a generalizable benchmark that may justifiably be used in forthcoming deliberative events exploring different topics with different audiences. PMID:25164558

  19. Advanced Taste Sensors Based on Artificial Lipids with Global Selectivity to Basic Taste Qualities and High Correlation to Sensory Scores

    Directory of Open Access Journals (Sweden)

    Yoshikazu Kobayashi

    2010-04-01

    Full Text Available Effective R&D and strict quality control of a broad range of foods, beverages, and pharmaceutical products require objective taste evaluation. Advanced taste sensors using artificial-lipid membranes have been developed based on concepts of global selectivity and high correlation with human sensory score. These sensors respond similarly to similar basic tastes, which they quantify with high correlations to sensory score. Using these unique properties, these sensors can quantify the basic tastes of saltiness, sourness, bitterness, umami, astringency and richness without multivariate analysis or artificial neural networks. This review describes all aspects of these taste sensors based on artificial lipid, ranging from the response principle and optimal design methods to applications in the food, beverage, and pharmaceutical markets.

  20. Advanced Methods for Air Distribution in Occupied Spaces for Reduced Risk from Air-Borne Diseases and Improved Air Quality

    DEFF Research Database (Denmark)

    Bolashikov, Zhecho Dimitrov

    and by protecting medical staff, patients and visitors from cross-infection in hospital wards. The first part of the thesis focuses on improvement of inhaled air quality and thus reduction in the risk from cross-infection by advanced ventilation, providing clean air close to the occupants with personalized...... ventilation (PV) by applying control over the airflow interaction at the breathing zone. Two new control methods, namely control over the free convection layer around the human body and control over the personalized flow are studied when applied for different PV designs. The first method aims to reduce......, airplanes, etc. The second part of the thesis focuses on a novel ventilation strategy for reduction the risk of cross-infection for medical staff, visitors, and patients in hospital wards. The novel ventilation strategy is implemented by a specially developed device, named Hospital Bed Integrated...

  1. OH radical imaging in a DI diesel engine and the structure of the early diffusion flame

    Energy Technology Data Exchange (ETDEWEB)

    Dec, J.E.; Coy, E.B.

    1996-03-01

    Laser-sheet imaging studies have considerably advanced our understanding of diesel combustion; however, the location and nature of the flame zones within the combusting fuel jet have been largely unstudied. To address this issue, planar laser-induced fluorescence (PLIF) imaging of the OH radical has been applied to the reacting fuel jet of a direct-injection diesel engine of the ``heavy-duty`` size class, modified for optical access. An Nd:YAG-based laser system was used to pump the overlapping Q{sub 1}9 and Q{sub 2}8 lines of the (1,0) band of the A{yields}X transition at 284.01 nm, while the fluorescent emission from both the (0,O) and (1, I) bands (308 to 320 nm) was imaged with an intensified video camera. This scheme allowed rejection of elastically scattered laser light, PAH fluorescence, and laser-induced incandescence. OH PLIF is shown to be an excellent diagnostic for diesel diffusion flames. The signal is strong, and it is confined to a narrow region about the flame front because the threebody recombination reactions that reduce high flame-front OH concentrations to equilibrium levels occur rapidly at diesel pressures. No signal was evident in the fuel-rich premixed flame regions where calculations and burner experiments indicate that OH concentrations will be below detectable limits. Temporal sequences of OH PLIF images are presented showing the onset and development of the early diffusion flame up to the time that soot obscures the images. These images show that the diffusion flame develops around the periphery of the-downstream portion of the reacting fuel jet about half way through the premixed burn spike. Although affected by turbulence, the diffusion flame remains at the jet periphery for the rest of the imaged sequence.

  2. Interaction of Two Micro-slot Flames: Heat Release Rate and Flame Shape

    International Nuclear Information System (INIS)

    This paper studies the interaction between two identical micro-slot diffusion flames. Here, we define a micro-slot flame as a slot flame of which the slot width is less than about 1 mm. Because of its smallness, a micro-slot flame has a high heating density and can be used as a small heat source. However, the heat release rate of a single micro-slot flame is limited, and therefore, multiple micro-slot flames may be used to increase total heat release rate. As a first step, this paper considers a situation in which two micro-slot flames are used with certain burner spacing. When two diffusion flames are placed closely, flame shape changes from that of an isolated flame. Studying such flame shape change and resultant change in total heat release rate is the topic of this paper. Experiment is conducted and total heat release rate is measured by integrating CH* chemiluminescence recorded using a CCD camera and an optical filter of the wavelength of 430 nm. Two different burner materials, copper and glass, are tested to study the effect of heat loss to burners. An analytical model is applied to predict flame shape. In addition to the classical Burke-Schumann assumptions, two slot flames are modeled as line sources with zero width, enabling a simple analytical solution for the critical burner spacing at which two flames touch each other. The critical burner spacing is a key parameter that characterizes the interaction between two micro-slot flames. Computational fluid dynamics (CFD) simulations are then conducted to test the validity of the present theory. CFD results are favorably compared with the theoretical prediction

  3. Automated, Miniaturized and Integrated Quality Control-on-Chip (QC-on-a-Chip for Advanced Cell Therapy Applications

    Directory of Open Access Journals (Sweden)

    David eWartmann

    2015-09-01

    Full Text Available The combination of microfabrication-based technologies with cell biology has laid the foundation for the development of advanced in vitro diagnostic systems capable of evaluating cell cultures under defined, reproducible and standardizable measurement conditions. In the present review we describe recent lab-on-a-chip developments for cell analysis and how these methodologies could improve standard quality control in the field of manufacturing cell-based vaccines for clinical purposes. We highlight in particular the regulatory requirements for advanced cell therapy applications using as an example dendritic cell-based cancer vaccines to describe the tangible advantages of microfluidic devices that overcome most of the challenges associated with automation, miniaturization and integration of cell-based assays. As its main advantage lab-on-a-chip technology allows for precise regulation of culturing conditions, while simultaneously monitoring cell relevant parameters using embedded sensory systems. State-of-the-art lab-on-a-chip platforms for in vitro assessment of cell cultures and their potential future applications for cell therapies and cancer immunotherapy are discussed in the present review.

  4. Automated, Miniaturized and Integrated Quality Control-on-Chip (QC-on-a-Chip) for Advanced Cell Therapy Applications

    Science.gov (United States)

    Wartmann, David; Rothbauer, Mario; Kuten, Olga; Barresi, Caterina; Visus, Carmen; Felzmann, Thomas; Ertl, Peter

    2015-09-01

    The combination of microfabrication-based technologies with cell biology has laid the foundation for the development of advanced in vitro diagnostic systems capable of evaluating cell cultures under defined, reproducible and standardizable measurement conditions. In the present review we describe recent lab-on-a-chip developments for cell analysis and how these methodologies could improve standard quality control in the field of manufacturing cell-based vaccines for clinical purposes. We highlight in particular the regulatory requirements for advanced cell therapy applications using as an example dendritic cell-based cancer vaccines to describe the tangible advantages of microfluidic devices that overcome most of the challenges associated with automation, miniaturization and integration of cell-based assays. As its main advantage lab-on-a-chip technology allows for precise regulation of culturing conditions, while simultaneously monitoring cell relevant parameters using embedded sensory systems. State-of-the-art lab-on-a-chip platforms for in vitro assessment of cell cultures and their potential future applications for cell therapies and cancer immunotherapy are discussed in the present review.

  5. Flame dynamics of a meso-scale heat recirculating combustor

    Energy Technology Data Exchange (ETDEWEB)

    Vijayan, V.; Gupta, A.K. [Department of Mechanical Engineering, University of Maryland, College Park, MD 20742 (United States)

    2010-12-15

    The dynamics of premixed propane-air flame in a meso-scale ceramic combustor has been examined here. The flame characteristics in the combustor were examined by measuring the acoustic emissions and preheat temperatures together with high-speed cinematography. For the small-scale combustor, the volume to surface area ratio is small and hence the walls have significant effect on the global flame structure, flame location and flame dynamics. In addition to the flame-wall thermal coupling there is a coupling between flame and acoustics in the case of confined flames. Flame-wall thermal interactions lead to low frequency flame fluctuations ({proportional_to}100 Hz) depending upon the thermal response of the wall. However, the flame-acoustic interactions can result in a wide range of flame fluctuations ranging from few hundred Hz to few kHz. Wall temperature distribution is one of the factors that control the amount of reactant preheating which in turn effects the location of flame stabilization. Acoustic emission signals and high-speed flame imaging confirmed that for the present case flame-acoustic interactions have more significant effect on flame dynamics. Based on the acoustic emissions, five different flame regimes have been identified; whistling/harmonic mode, rich instability mode, lean instability mode, silent mode and pulsating flame mode. (author)

  6. Unsteady planar diffusion flames: Ignition, travel, burnout

    Science.gov (United States)

    Fendell, F.; Wu, F.

    1995-01-01

    In microgravity, a thin planar diffusion flame is created and thenceforth travels so that the flame is situated at all times at an interface at which the hydrogen and oxygen meet in stoichiometric proportion. If the initial amount of hydrogen is deficient relative to the initial amount of oxygen, then the planar flame will travel further and further into the half volume initially containing hydrogen, until the hydrogen is (virtually) fully depleted. Of course, when the amount of residual hydrogen becomes small, the diffusion flame is neither vigorous nor thin; in practice, the flame is extinguished before the hydrogen is fully depleted, owing to the finite rate of the actual chemical-kinetic mechanism. The rate of travel of the hydrogen-air diffusion flame is much slower than the rate of laminar flame propagation through a hydrogen-air mixture. This slow travel facilitates diagnostic detection of the flame position as a function of time, but the slow travel also means that the time to burnout (extinction) probably far exceeds the testing time (typically, a few seconds) available in earth-sited facilities for microgravity-environment experiments. We undertake an analysis to predict (1) the position and temperature of the diffusion flame as a function of time, (2) the time at which extinction of the diffusion flame occurs, and (3) the thickness of quench layers formed on side walls (i.e., on lateral boundaries, with normal vectors parallel to the diffusion-flame plane), and whether, prior to extinction, water vapor formed by burning will condense on these cold walls.

  7. Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf Carbonate Reservoir, Class II

    Energy Technology Data Exchange (ETDEWEB)

    Hickman, T. Scott; Justice, James J.; Egg, Rebecca

    2001-08-07

    The Oxy operated Class 2 Project at West Welch Project is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO2 injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir demonstration characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO2 flood design based on the reservoir characterization.

  8. Advances in the cryopreservation of sea-urchin embryos: Potential application in marine water quality assessment.

    Science.gov (United States)

    Bellas, Juan; Paredes, Estefanía

    2011-06-01

    Among the most widely used biological techniques in marine pollution assessment, the sea-urchin embryo-larval bioassay is in an advanced developmental stage. Cryopreservation might help to overcome the problem of the spawning seasonality and therefore strengthen the use of those embryo-larval bioassays. This work investigates different factors influencing cryopreservation of sea-urchin embryos, including the cooling rates and holding temperatures, the seeding, or the impact of plunging into liquid nitrogen. The blastula stage yielded better results than the fertilised egg, and the most effective cryoprotectants combination was dimethyl sulfoxide 1.5M plus trehalose 0.04M. The optimised protocol developed begins with an initial hold at 4°C for 2min, followed by cooling at -1°Cmin(-1) to -12°C. At this point a seeding step was incorporated with a 2min hold, followed by a second cooling at -1°Cmin(-1) to -80°C. After a final hold of 2min the cryovials are transferred into liquid nitrogen for storage. Although the cryopreservation processes might cause a delay in the development of sea-urchin embryos, high larval growth (71-98% of controls) was obtained when cryopreserved blastulae were further incubated for 72-96h in artificial seawater. We conclude that embryo-larval bioassays with cryopreserved sea-urchin blastulae are suitable for use in marine pollution monitoring programs and may be considered as an acceptable solution to the reproductive seasonality of sea-urchin species. PMID:21338597

  9. Impact of flame-wall interaction on premixed flame dynamics and transfer function characteristics

    KAUST Repository

    Kedia, K.S.

    2011-01-01

    In this paper, we numerically investigate the response of a perforated-plate stabilized laminar methane-air premixed flame to imposed inlet velocity perturbations. A flame model using detailed chemical kinetics mechanism is applied and heat exchange between the burner plate and the gas mixture is incorporated. Linear transfer functions, for low mean inlet velocity oscillations, are analyzed for different equivalence ratio, mean inlet velocity, plate thermal conductivity and distance between adjacent holes. The oscillations of the heat exchange rate at the top of the burner surface plays a critical role in driving the growth of the perturbations over a wide range of conditions, including resonance. The flame response to the perturbations at its base takes the form of consumption speed oscillations in this region. Flame stand-off distance increases/decreases when the flame-wall interaction strengthens/weakens, impacting the overall dynamics of the heat release. The convective lag between the perturbations and the flame base response govern the phase of heat release rate oscillations. There is an additional convective lag between the perturbations at the flame base and the flame tip which has a weaker impact on the heat release rate oscillations. At higher frequencies, the flame-wall interaction is weaker and the heat release oscillations are driven by the flame area oscillations. The response of the flame to higher amplitude oscillations are used to gain further insight into the mechanisms. © 2010 Published by Elsevier Inc. on behalf of The Combustion Institute. All rights reserved.

  10. Reverse-Engineering of the Cryptanalytic Attack Used in the Flame Super-Malware

    NARCIS (Netherlands)

    Fillinger, M.J.; Stevens, M.M.J.; Iwata, T.; Cheon, J.H.

    2015-01-01

    In May 2012, a highly advanced malware for espionage dubbed Flame was found targeting the Middle-East. As it turned out, it used a forged signature to infect Windows machines by MITM-ing Windows Update. Using counter-cryptanalysis, Stevens found that the forged signature was made possible by a chos

  11. Flaming in CMC: Prometheus' Fire or Inferno's?

    Science.gov (United States)

    Abrams, Zsuzsanna Ittzes

    2003-01-01

    Reports on a descriptive study with 75 intermediate college learners of German participating in two sessions of synchronous computer mediated communication during the course of a semester that investigated students' flaming behavior--aggressive interpersonal language and rude behavior. Shows that not only is flaming a very infrequent occurrence,…

  12. Chemical processes in the HNF flame

    NARCIS (Netherlands)

    Ermolin, N.E.; Zarko, V.E.; Keizers, H.L.J.

    2006-01-01

    Results of modeling the HNF flame structure are presented. From an analysis of literature data on the thermal decomposition and combustion of HNF, it is concluded that the dissociative vaporization of HNF proceeds via the route HNFliq → (N2H4)g + (HC(NO 2)3)g. The flame structure is modeled using a

  13. Propagation Regime of Iron Dust Flames

    Science.gov (United States)

    Tang, Francois-David; Goroshin, Samuel; Higgins, Andrew J.

    2012-01-01

    A flame propagating through an iron-dust mixture can propagate in two asymptotic regimes. When the characteristic time of heat transfer between particles is much smaller than the characteristic time of particle combustion, the flame propagates in the continuum regime where the heat released by reacting particles can be modelled as a space-averaged function. In contrast, when the characteristic time of heat transfer is much larger than the particle reaction time, the flame can no longer be treated as a continuum due to dominating effects associated with the discrete nature of the particle reaction. The discrete regime is characterized by weak dependence of the flame speed on the oxygen concentration compared to the continuum regime. The discrete regime is observed in flames propagating through an iron dust cloud within a gas mixture containing xenon, while the continuum regime is obtained when xenon is substituted with helium.

  14. Flame assisted synthesis of catalytic ceramic membranes

    DEFF Research Database (Denmark)

    Johansen, Johnny; Mosleh, Majid; Johannessen, Tue;

    2004-01-01

    will be spherical due to the fast coalescence at the high temperatures in the flame. The primary product from the flame pyrolysis is an aerosol of metal oxide nanoparticles. The aerosol gas from the flame can be utilized for several different purposes, depending on the precursors fed to the flame. With the present...... technology it is possible to make supported catalysts, composite metal oxides, catalytically active surfaces, and porous ceramic membranes. Membrane layers can be formed by using a porous substrate tube (or surface) as a nano-particle filter. The aerosol gas from the flame is led through a porous substrate...... tube, where a part of the gas is sucked through the wall of the substrate, thereby creating a thin filter cake on the inner surface of the substrate tube. The top-layer can be deposited directly on a coarse pore structure. Since the Brownian motion of the aerosol particles is fast compared to the fluid...

  15. Cool Sooting Flames of Hydrocarbons

    Institute of Scientific and Technical Information of China (English)

    Z.A. MANSUROV

    2001-01-01

    This paper presents the study of polycyclic aromatic hydrocarbons (PAH) and paramagnetism of soot particles sampled from cool sooting flames of methane and propane in a separately-heated two-sectional reactor under atmospheric pressure at the reactor temperatures of 670-1170 K. The temperature profiles of the flames were studied. The sampling was carried out with a quartz sampler and the samples were frozen with liquid nitrogen. A number of polyaromatic hydrocarbons such as pyrene, fluoranthene, coronene, anthanthrene, 1,12-benzperylene,were identified by spectroscopic methods in the extract of soot. The processes of soot formation at methaneoxygen mixture combustion in the electric field with applied potential changed from 0 to 2,2 kV at different polarity of electrodes have been investigated. It has been stated that at the electrical field application, an increase in soot particle sizes and soot yield occurs; besides, at the application of the field, speeding up the positively charged particles, the interplanar distance decreases. On the basis of investigation of soot particles paramagnetism, it was shown that initially soot particles have high carcinogetic activity and pollute the environment owing to a rapid decrease of the number of these radical centers. The reduction of the radical concentration is connected with radical recombination on soot.

  16. Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Menapace, J A; Schaffers, K I; Bayramian, A J; Davis, P J; Ebbers, C A; Wolfe, J E; Caird, J A; Barty, C J; Joyce, D B; Schmid, K; Schmid, F

    2007-10-09

    Ti:sapphire has become the premier lasing medium material for use in solid-state femtosecond high-peak power laser systems because of its wide wavelength tuning range. With a tuneable range from 680 to 1100 nm, peaking at 800 nm, Ti:sapphire lasing crystals can easily be tuned to the required pump wavelength and provide very high pump brightness due to their good beam quality and high output power of typically several watts. Femtosecond lasers are used for precision cutting and machining of materials ranging from steel to tooth enamel to delicate heart tissue and high explosives. These ultra-short pulses are too brief to transfer heat or shock to the material being cut, which means that cutting, drilling, and machining occur with virtually no damage to surrounding material. Furthermore, these lasers can cut with high precision, making hairline cuts of less than 100 microns in thick materials along a computer-generated path. Extension of laser output to higher energies is limited by the size of the amplification medium. Yields of high quality large diameter crystals have been constrained by lattice distortions that may appear in the boule limiting the usable area from which high quality optics can be harvested. Lattice distortions affect the transmitted wavefront of these optics which ultimately limits the high-end power output and efficiency of the laser system, particularly when operated in multi-pass mode. To make matters even more complicated, Ti:sapphire is extremely hard (Mohs hardness of 9 with diamond being 10) which makes it extremely difficult to accurately polish using conventional methods without subsurface damage or significant wavefront error. In this presentation, we demonstrate for the first time that Magnetorheological finishing (MRF) can be used to compensate for the lattice distortions in Ti:sapphire by perturbing the transmitted wavefront. The advanced MRF techniques developed allow for precise polishing of the optical inverse of lattice

  17. Flame Structure and Emissions of Strongly-Pulsed Turbulent Diffusion Flames with Swirl

    Science.gov (United States)

    Liao, Ying-Hao

    This work studies the turbulent flame structure, the reaction-zone structure and the exhaust emissions of strongly-pulsed, non-premixed flames with co-flow swirl. The fuel injection is controlled by strongly-pulsing the fuel flow by a fast-response solenoid valve such that the fuel flow is completely shut off between pulses. This control strategy allows the fuel injection to be controlled over a wide range of operating conditions, allowing the flame structure to range from isolated fully-modulated puffs to interacting puffs to steady flames. The swirl level is controlled by varying the ratio of the volumetric flow rate of the tangential air to that of the axial air. For strongly-pulsed flames, both with and without swirl, the flame geometry is strongly impacted by the injection time. Flames appear to exhibit compact, puff-like structures for short injection times, while elongated flames, similar in behaviors to steady flames, occur for long injection times. The flames with swirl are found to be shorter for the same fuel injection conditions. The separation/interaction level between flame puffs in these flames is essentially governed by the jet-off time. The separation between flame puffs decreases as swirl is imposed, consistent with the decrease in flame puff celerity due to swirl. The decreased flame length and flame puff celerity are consistent with an increased rate of air entrainment due to swirl. The highest levels of CO emissions are generally found for compact, isolated flame puffs, consistent with the rapid quenching due to rapid dilution with excess air. The imposition of swirl generally results in a decrease in CO levels, suggesting more rapid and complete fuel/air mixing by imposing swirl in the co-flow stream. The levels of NO emissions for most cases are generally below the steady-flame value. The NO levels become comparable to the steady-flame value for sufficiently short jet-off time. The swirled co-flow air can, in some cases, increase the NO

  18. Advanced biosensing methodologies developed for evaluating performance quality and safety of emerging biophotonics technologies and medical devices (Conference Presentation)

    Science.gov (United States)

    Ilev, Ilko K.; Walker, Bennett; Calhoun, William; Hassan, Moinuddin

    2016-03-01

    Biophotonics is an emerging field in modern biomedical technology that has opened up new horizons for transfer of state-of-the-art techniques from the areas of lasers, fiber optics and biomedical optics to the life sciences and medicine. This field continues to vastly expand with advanced developments across the entire spectrum of biomedical applications ranging from fundamental "bench" laboratory studies to clinical patient "bedside" diagnostics and therapeutics. However, in order to translate these technologies to clinical device applications, the scientific and industrial community, and FDA are facing the requirement for a thorough evaluation and review of laser radiation safety and efficacy concerns. In many cases, however, the review process is complicated due the lack of effective means and standard test methods to precisely analyze safety and effectiveness of some of the newly developed biophotonics techniques and devices. There is, therefore, an immediate public health need for new test protocols, guidance documents and standard test methods to precisely evaluate fundamental characteristics, performance quality and safety of these technologies and devices. Here, we will overview our recent developments of novel test methodologies for safety and efficacy evaluation of some emerging biophotonics technologies and medical devices. These methodologies are based on integrating the advanced features of state-of-the-art optical sensor technologies and approaches such as high-resolution fiber-optic sensing, confocal and optical coherence tomography imaging, and infrared spectroscopy. The presentation will also illustrate some methodologies developed and implemented for testing intraocular lens implants, biochemical contaminations of medical devices, ultrahigh-resolution nanoscopy, and femtosecond laser therapeutics.

  19. Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf Carbonate Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Rebecca Egg

    2002-09-30

    The OXY-operated Class 2 Project at West Welch is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO{sub 2} injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO{sub 2} flood design based on the reservoir characterization. Although Budget Period 1 for the Project officially ended 12/31/96, reservoir characterization and simulation work continued during the Budget Period 2. During the fifth and sixth annual reporting periods (8/3/98-8/2/00) covered by this report, work continued on interpretation of the cross well seismic data to create porosity and permeability profiles which were distributed into the reservoir geostatistically. The initial interwell seismic CO{sub 2} monitor survey was conducted, the acquired data processed and interpretation started. Only limited well work and facility construction was conducted in the project area. The CO{sub 2} injection initiated in October 1997 was continued, although the operator had to modify the operating plan in response to low injection rates, well performance and changes in CO{sub 2} supply. CO{sub 2} injection was focused in a smaller area to increase the reservoir processing rate. By the end of the reporting period three producers had shown sustained oil rate increases and ten wells had experienced gas (CO{sub 2}) breakthrough.

  20. Advances in Electromyogram Signal Classification to Improve the Quality of Life for the Disabled and Aged People

    Directory of Open Access Journals (Sweden)

    M. D.R. Ahsan

    2010-01-01

    Full Text Available Problem statement: The social demands for the Quality Of Life (QOL are increasing with the exponentially expanding silver generation. To improve the QOL of the disabled and elderly people, robotic researchers and biomedical engineers have been trying to combine their techniques into the rehabilitation systems. Various biomedical signals (biosignals acquired from a specialized tissue, organ, or cell system like the nervous system are the driving force for the entire system. Examples of biosignals include Electro-Encephalogram (EEG, Electrooculogram (EOG, Electroneurogram (ENG and (EMG. Approach: Among the biosignals, the research on EMG signal processing and controlling is currently expanding in various directions. EMG signal based research is ongoing for the development of simple, robust, user friendly, efficient interfacing devices/systems for the disabled. The advancement can be observed in the area of robotic devices, prosthesis limb, exoskeleton, wearable computer, I/O for virtual reality games and physical exercise equipments. An EMG signal based graphical controller or interfacing system enables the physically disabled to use word processing programs, other personal computer software and internet. Results: Depending on the application, the acquired and processed signals need to be classified for interpreting into mechanical force or machine/computer command. Conclusion: This study focused on the advances and improvements on different methodologies used for EMG signal classification with their efficiency, flexibility and applications. This review will be beneficial to the EMG signal researchers as a reference and comparison study of EMG classifier. For the development of robust, flexible and efficient applications, this study opened a pathway to the researchers in performing future comparative studies between different EMG classification methods.

  1. Impact of increasing levels of advanced iterative reconstruction on image quality in low-dose cardiac CT angiography

    International Nuclear Information System (INIS)

    Purpose: To investigate the effects of an advanced iterative reconstruction (IR) technique on subjective and objective image quality (IQ) in low-dose cardiac CT angiography (CCTA). Materials and Methods: 30 datasets of prospectively triggered 'step-and-shoot' CCTA scans acquired on a 256-slice CT scanner with optimized exposure settings were processed on a prototype IR system using filtered back-projection (FBP) and 4 levels of advanced IR (iDose4, Philips) providing incremental rates of IR (level 2, 4, 6, 7). In addition, the effects of different reconstruction kernels (semi-smooth [CB], standard with edge-enhancement [XCB]) and a 'multi-resolution' feature [MR] to preserve the noise power spectrum were evaluated resulting in a total of n = 480 image sets. Contrast-to-noise ratios (CNR) were computed from regions of interest at 9 coronary locations. The subjective IQ was rated on a 4-point-scale with 'classic' image appearance and noise-related artifacts as main criteria. Results: At an effective dose of 1.7 ± 0.7 mSv, the CNR significantly improved with every increasing level of IR (range: 14.2-27.8; p < 0.001) with the best objective IQ at the highest level of IR (level 7). The subjective IQ, however, was rated best at the medium level of IR (level 4) with minimal artifacts and a more 'classic' image appearance when compared to higher IR levels. The XCB kernel provided better subjective ratings than CB (p < 0.05) and the MR feature further increased the IQ at a high level of IR. Conclusion: The objective IQ of low-dose CCTA progressively improves with an increasing level of IR. The best subjective IQ, however, is reached at medium levels of IR combined with an edge-enhancing kernel allowing for preservation of a 'classic' image appearance suggesting application in the clinical routine. (orig.)

  2. Palliative chemotherapy beyond three courses conveys no survival or consistent quality-of-life benefits in advanced non-small-cell lung cancer

    DEFF Research Database (Denmark)

    von Plessen, C; Bergman, B; Andresen, O;

    2006-01-01

    This randomised multicentre trial was conducted to establish the optimal duration of palliative chemotherapy in advanced non-small-cell lung cancer (NSCLC). We compared a policy of three vs six courses of new-generation platinum-based combination chemotherapy with regard to effects on quality...

  3. Influence of comorbidity on survival, toxicity and health-related quality of life in patients with advanced non-small-cell lung cancer receiving platinum-doublet chemotherapy

    DEFF Research Database (Denmark)

    Grønberg, Bjørn H; Sundstrøm, Stein; Kaasa, Stein;

    2010-01-01

    AIM OF THE STUDY: To investigate whether patients with severe comorbidity receiving platinum-based chemotherapy for advanced non-small-cell lung cancer (NSCLC) have a shorter overall survival, experience more toxicity or more deterioration of health-related quality of life (HRQoL) than other...

  4. Laminar Soot Processes Experiment Shedding Light on Flame Radiation

    Science.gov (United States)

    Urban, David L.

    1998-01-01

    The Laminar Soot Processes (LSP) experiment investigated soot processes in nonturbulent, round gas jet diffusion flames in still air. The soot processes within these flames are relevant to practical combustion in aircraft propulsion systems, diesel engines, and furnaces. However, for the LSP experiment, the flames were slowed and spread out to allow measurements that are not tractable for practical, Earth-bound flames.

  5. Particle clustering in turbulent premixed flames

    Science.gov (United States)

    F, Battista; F, Picano; G, Troiani; M, Casciola C.

    2011-12-01

    Transport of inertial particles in turbulent reacting flows is frequent in a number of engineering and natural systems. Aim of this work is to illustrate the effect of the fluctuating instantaneous flame front on the particle spatial distribution. To this purpose a Direct Numerical Simulation of a Bunsen premixed flame seeded with small inertial particles is performed. The flamelet Stokes number Stfl, defined as the ratio between the particle relaxation time and the flame front time scale, is found to be the proper parameter to characterize the particle dynamics in a premixed flame. Clustering of inertial particles is apparent, especially beyond the flame front. The amount of particle segregation is here quantified by the clustering index and two distinct contributions are found to interplay. The first is independent of the particle inertia and affects also tracers. Actually it is associated to the abrupt variation of the particle concentration induced by the fluid expansion across the flame front. The second effect is mainly due to the time lag associated to the particle inertia that, in proximity of the front, affects both the mean and the fluctuation of the particle number in a fixed volume. The global effect results in an intense clustering of the inertial particles in the flame brush region with a maximum for particles with flamelet Stokes number: Stfl = Script O(1).

  6. Progress and challenges in swirling flame dynamics

    Science.gov (United States)

    Candel, Sébastien; Durox, Daniel; Schuller, Thierry; Palies, Paul; Bourgouin, Jean-François; Moeck, Jonas P.

    2012-11-01

    In many continuous combustion processes the flame is stabilized by swirling the injected flow. This is the case for example in aeroengine combustors or in gas turbines where aerodynamic injectors impart a rotating component to the flow to create a central recirculation zone which anchors the flame. Swirling flame dynamics is of technical interest and also gives rise to interesting scientific issues. Some of the recent progress in this field will be reviewed. It is first shown that the swirler response to incident acoustic perturbations generates a vorticity wave which is convected by the flow. A result of this process is that the swirl number fluctuates. It is then shown that the flame response is defined by a combination of heat release rate fluctuations induced by the incoming acoustic and convective perturbations. This is confirmed by experimental measurements and by large eddy simulations of the reactive flow. Measured flame describing functions (FDFs) are then used to characterize the nonlinear response of swirling flames to incident perturbations and determine the regimes of instability of a generic system comprising an upstream manifold, an injector equipped with a swirler and a combustion chamber confining the flame. The last part of this article is concerned with interactions of the precessing vortex core (PVC) with incoming acoustic perturbations. The PVC is formed at high swirl number and this hydrodynamic helical instability gives rise to some interesting nonlinear interactions between the acoustic frequency, the PVC frequency and their difference frequency.

  7. Role of compressibility in moderating flame acceleration in tubes.

    Science.gov (United States)

    Bychkov, Vitaly; Akkerman, V'yacheslav; Valiev, Damir; Law, Chung K

    2010-02-01

    The effect of gas compression on spontaneous flame acceleration leading to deflagration-to-detonation transition is studied theoretically for small Reynolds number flame propagation from the closed end of a tube. The theory assumes weak compressibility through expansion in small Mach number. Results show that the flame front accelerates exponentially during the initial stage of propagation when the Mach number is negligible. With continuous increase in the flame velocity with respect to the tube wall, the flame-generated compression waves subsequently moderate the acceleration process by affecting the flame shape and velocity, as well as the flow driven by the flame. PMID:20365653

  8. Combustion characteristics of Mg−CO2 counterflow diffusion flames

    OpenAIRE

    Fukuchi, Aporo; Kawashima, Masaru; Yuasa, Saburo

    1996-01-01

    To examine the details of the Mg−CO2 combustion consisting of the gas-phase reactions and the surface reactions, we tried to separate the Mg−CO2 flame from the surface reactions. For this purpose, we formed a stable Mg−CO2 counterflow diffusion flame between the Mg vapor and a CO2 stream by using a Mg vaporizer with many small ejection holes.The Mg−CO2 counterflow diffusion flames contained two types of flames: the luminous flame and the dark flame. In the luminous flame, the homogeneous reac...

  9. The FLAME project in Atomki

    International Nuclear Information System (INIS)

    Complete text of publication follows. Eleven regions of eight Central European countries have launched the FLAME Project in 2010 (Future Laboratory for the diffusion and Application of innovation in Material Sciences and Engineering) to start and manage a new initiative of a network for innovation activities in the MS and E sector. The project aimed at supporting actors in the field of materials science and exploiting their research and commercial potentials. FLAME partners encourage trans-regional cooperation between R and D centres, universities, start-ups and SMEs by helping companies to distribute their innovations and supporting research in transferring results to the market. The project will implement a new cooperation model: the 'Future Lab', where duly trained 'regional facilitation coaches' will assist SMEs in accessing the whole Central European MS and E market and research potential. Each Future Lab will be specialized on thematic fields and help to make efficient use of local and regional potentials. The three Future Labs will be hosted by the Austrian, Italian and Slovenian partner organizations. Figure 1. Competence and innovation landscape on the FLAME website. Source: http://www.flameurope.eu/mse-actors-145.html As the first step of project implementation in 2011 the competence and innovation maps within the participating regions were elaborated in order to list the relevant actors in the MS and E sector (Figure 1). In 2011, each project partner delegated two regional professionals as facilitation coaches to attend four training weeks across Europe. The facilitation coaches play an active role in the exchange of information and in motivating collaboration between research institutions and enterprises on technology based projects. The training sessions were located at four of the project partners: Kapfenberg/Austria (lead partner - Area m Styria); Warsaw/Poland (PP2 - Warsaw University of Technology); Debrecen/Hungary (PP5 - Atomki); Milan/Italy (PP

  10. The dilution effect on the extinction of wall diffusion flame

    Directory of Open Access Journals (Sweden)

    Ghiti Nadjib

    2014-12-01

    Full Text Available The dynamic process of the interaction between a turbulent jet diffusion methane flame and a lateral wall was experimentally studied. The evolution of the flame temperature field with the Nitrogen dilution of the methane jet flame was examined. The interaction between the diffusion flame and the lateral wall was investigated for different distance between the wall and the central axes of the jet flame. The dilution is found to play the central role in the flame extinction process. The flame response as the lateral wall approaches from infinity and the increasing of the dilution rate make the flame extinction more rapid than the flame without dilution, when the nitrogen dilution rate increase the flame temperature decrease.

  11. Flame Acceleration Tests with Hydrogen Combustions

    International Nuclear Information System (INIS)

    According to the domestic and foreign regulations, a detonation or DDT (deflagration to detonation transition) by a hydrogen combustion should be prohibited to occur in a containment of a nuclear power plant. A hydrogen control in the IRWST(Incontainment Refueling Water Storage Tank) under a severe accident still remains a debatable issue to be solved in APR1400. The characteristics of the hydrogen flame in the IRWST expected during the station black-out (SBO) and total loss of feed water (LOFW) accidents have been evaluated based on a sigma-lambda criteria from the simulation results by the numerical codes such as GASFLOW. And it was found that hydrogen mixture was non-flammable most of the accident time when the non-condensed steam was released into the free volume of the IRWST, but there existed a small period of time with a high possibility of a flame acceleration during the SBO accident because most of the steam discharged from sparger was well condensed. Therefore, detail analysis and experiment of the hydrogen flame should be required to fix a DDT possibility by the hydrogen combustion in the IRWST of the APR1400. Most experiments on the hydrogen combustion have been limited only to straight pipes or channels. However, the hydrogen flame acceleration phenomena in the IRWST with a closed annular path may be different from those in the straight path in respect to a centrifugal force and degree of freedom in flame propagation etc. So, an experiment of hydrogen combustion in a closed annular chamber is needed to find out the geometrical effect on the flame propagation and to validate the numerical results. KAERI has been performing the experiments of the hydrogen combustion in the IRWST. As the fist stage, flame acceleration tests with the hydrogen combustions are studied preliminarily for a circular straight pipe to confirm the characteristics hydrogen flame propagation, and to evaluate flame detection systems

  12. Quality of life assessment with different radiotherapy schedules in palliative management of advanced carcinoma esophagus: A prospective randomized study

    Directory of Open Access Journals (Sweden)

    Shaveta Mehta

    2008-01-01

    Full Text Available Aim: To investigate the quality of life (QOL of patients with advanced carcinoma esophagus treated with different palliative radiation schedules. Methods: Sixty-two consecutive patients with inoperable, non-metastatic carcinoma of the esophagus were randomly allocated to Arm-A (external radiotherapy 30 Gy/10 fractions + brachytherapy 12 Gy/two sessions, Arm-B (external radiotherapy 30 Gy /10 fractions and Arm-C (external radiotherapy 20Gy /five fractions. The QOL was assessed using the European Organization for Research and Treatment of Cancer questionnaire at presentation, after treatment and at 3 months follow-up. Results: The mean QOL score improved, in arm-A from 38 to 52 after treatment and 56 at 3 months, in arm-B from 30 to 44 after treatment and 55 at 3 months and in arm-C from 24 to 40 after treatment but decreased to 37 at 3 months. Improvement in dysphagia scores at the first follow-up was 46.1% in arm-A, 25.0% in arm-B and 22.6% in arm-C. The difference was maintained at 3 months, with maximum improvement in arm-A (57.6%. No significant differences were found between the three arms with regard to complications and additional procedures needed for relief of dysphagia. Conclusion: In comparison with external radiotherapy alone, external radiotherapy with intraluminal brachytherapy has shown a trend toward better QOL and consistent dysphagia relief without significant difference in adverse effects.

  13. Testing an advanced satellite technique for dust detection as a decision support system for the air quality assessment

    Science.gov (United States)

    Falconieri, Alfredo; Filizzola, Carolina; Femiano, Rossella; Marchese, Francesco; Sannazzaro, Filomena; Pergola, Nicola; Tramutoli, Valerio; Di Muro, Ersilia; Divietri, Mariella; Crisci, Anna Maria; Lovallo, Michele; Mangiamele, Lucia; Vaccaro, Maria Pia; Palma, Achille

    2014-05-01

    In order to correctly apply the European directive for air quality (2008/50/CE), local Authorities are often requested to discriminate the possible origin (natural/anthropic) of anomalous concentration of pollutants in the air (art.20 Directive 2008/50/CE). In this framework, it's been focused on PM10 and PM2,5 concentrations and sources. In fact, depending on their origin, appropriate counter-measures can be taken devoted to prevent their production (e.g. by traffic restriction) or simply to reduce their impact on citizen health (e.g. information campaigns). In this context suitable satellite techniques can be used in order to identify natural sources (particularly Saharan dust, but also volcanic ash or forest fire smoke) that can be responsible of over-threshold concentration of PM10/2,5 in populated areas. In the framework of the NIBS (Networking and Internationalization of Basilicata Space Technologies) project, funded by the Basilicata Region within the ERDF 2007-2013 program, the School of Engineering of University of Basilicata, the Institute of Methodologies for Environmental Analysis of National Research Council (IMAA-CNR) and the Regional Agency for the Protection of the Environment of Basilicata Region (ARPAB) have started a collaboration devoted to assess the potential of the use of advanced satellite techniques for Saharan dust events identification to support ARPAB activities related to the application of the European directive for air quality (2008/50/CE) in Basilicata region. In such a joint activity, the Robust Satellite Technique (RST) approach has been assessed and tested as a decision support system for monitoring and evaluating air quality at local and regional level. In particular, RST-DUST products, derived by processing high temporal resolution data provided by SEVIRI (Spinning Enhanced Visible and Infrared Imager) sensor on board Meteosat Second Generation platforms, have been analysed together with PM10 measurements performed by the ground

  14. Methane Formation by Flame-Generated Hydrogen Atoms in the Flame Ionization Detector

    DEFF Research Database (Denmark)

    Holm, Torkil; Madsen, Jørgen Øgaard

    1996-01-01

    The precombustion degradation of organic compounds in the flame ionization detector has been studied (1) by heating the additives in hydrogen in a quartz capillary and analyzing the reaction products by GC and (2) by following the degradation of the additives in a hydrogen flame, by means of a thin...... fused silica probe inserted from the bottom of the flame and connected to the ion source of a mass spectrometer. The results show that the thermic hydrogenolysis of hydrocarbons at flame temperatures produces mixtures of methane, ethene, and ethyne. In the flame, however, ethyne, benzene, isobutane...... atoms, which are formed in the burning hydrogen and which diffuse into the inner core of the flame. The quantitative formation of methane appears to explain the "equal per carbon" rule for the detector response of hydrocarbons, since all carbons are "exchanged" for methane molecules....

  15. Effectiveness of the "Cancer Home-Life Intervention" on everyday activities and quality of life in people with advanced cancer living at home

    DEFF Research Database (Denmark)

    Brandt, Åse; Pilegaard, Marc Sampedro; Østergaard, Lisa Gregersen;

    2016-01-01

    applied in the participant’s home environment was developed. The objective of this study is to examine the effectiveness and cost-effectiveness of the Cancer Home-Life Intervention compared to usual care on the performance of and participation in everyday activities and quality of life in people...... in everyday activities, and whether it contributes to their health-related quality of life. The economic evaluation alongside the RCT will show if the Cancer Home-Life Intervention is cost-effective. The trial will also show the acceptability of the intervention to the target group, and whether subgroups......Background During the past decade an increasing number of people live with advanced cancer mainly due to improved medical treatment. Research has shown that many people with advanced cancer have problems with everyday activities, which have negative impact on their quality of life...

  16. Flaming alcoholic drinks: flirting with danger.

    Science.gov (United States)

    Tan, Alethea; Frew, Quentin; Yousif, Ali; Ueckermann, Nicola; Dziewulksi, Peter

    2014-01-01

    Alcohol-related burn injuries carry significant mortality and morbidity rates. Flaming alcoholic beverages served in trendy bars and clubs are becoming increasingly popular. The dangers associated with an ignited alcoholic drink are often underestimated by party goers whose risk assessment ability is already impaired by heavy alcohol consumption. The authors present two cases demonstrating the varied severity of burn injuries associated with flaming alcoholic drinks, and their clinical management. Consumption of flaming alcoholic drinks poses potential risks for burn injuries. Further support is required to enable national and local agencies to implement effective interventions in drinking environments. PMID:24043236

  17. Aromatics oxidation and soot formation in flames

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.B.; Pope, C.J.; Shandross, R.A.; Yadav, T. [Massachusetts Institute of Technology, Cambridge (United States)

    1993-12-01

    This project is concerned with the kinetics and mechanisms of aromatics oxidation and soot and fullerenes formation in flames. The scope includes detailed measurements of profiles of stable and radical species concentrations in low-pressure one-dimensional premixed flames. Intermediate species identifications and mole fractions, fluxes, and net reaction rates calculated from the measured profiles are used to test postulated reaction mechanisms. Particular objectives are to identify and to determine or confirm rate constants for the main benzene oxidation reactions in flames, and to characterize fullerenes and their formation mechanisms and kinetics.

  18. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : determination of organophosphate pesticides in whole water by continuous liquid-liquid extraction and capillary-column gas chromatography with flame photometric detection

    Science.gov (United States)

    Jha, Virendra K.; Wydoski, Duane S.

    2003-01-01

    A method for the isolation of 20 parent organophosphate pesticides and 5 organophosphate pesticide degradates from natural-water samples is described. Compounds are extracted from water samples with methylene chloride using a continuous liquid-liquid extractor for 6 hours. The solvent is evaporated using heat and a flow of nitrogen to a volume of 1 milliliter and solvent exchanged to ethyl acetate. Extracted compounds are determined by capillary-column gas chromatography with flame photometric detection. Single-operator derived method detection limits in three water-matrix samples ranged from 0.003 to 0.009 microgram per liter. Method performance was validated by spiking all compounds in three different matrices at three different concentrations. Eight replicates were analyzed at each concentration in each matrix. Mean recoveries of most method compounds spiked in surface-water samples ranged from 54 to 137 percent and those in ground-water samples ranged from 40 to 109 percent for all pesticides. Recoveries in reagent-water samples ranged from 42 to 104 percent for all pesticides. The only exception was O-ethyl-O-methyl-S-propylphosphorothioate, which had variable recovery in all three matrices ranging from 27 to 79 percent. As a result, the detected concentration of O-ethyl-O-methyl-S-propylphosphorothioate in samples is reported in this method with an estimated remark code. Based on the performance issue, two more compounds, disulfoton and ethion monoxon, also will be reported in this method with an estimated remark code. Estimated-value compounds, which are ?E-coded? in the data base, do not meet the performance criteria for unqualified quantification, but are retained in the method because the compounds are important owing to high use or potential environmental effects and because analytical performance has been consistent and reproducible.

  19. Direct numerical simulations of non-premixed ethylene-air flames: Local flame extinction criterion

    KAUST Repository

    Lecoustre, Vivien R.

    2014-11-01

    Direct Numerical Simulations (DNS) of ethylene/air diffusion flame extinctions in decaying two-dimensional turbulence were performed. A Damköhler-number-based flame extinction criterion as provided by classical large activation energy asymptotic (AEA) theory is assessed for its validity in predicting flame extinction and compared to one based on Chemical Explosive Mode Analysis (CEMA) of the detailed chemistry. The DNS code solves compressible flow conservation equations using high order finite difference and explicit time integration schemes. The ethylene/air chemistry is simulated with a reduced mechanism that is generated based on the directed relation graph (DRG) based methods along with stiffness removal. The numerical configuration is an ethylene fuel strip embedded in ambient air and exposed to a prescribed decaying turbulent flow field. The emphasis of this study is on the several flame extinction events observed in contrived parametric simulations. A modified viscosity and changing pressure (MVCP) scheme was adopted in order to artificially manipulate the probability of flame extinction. Using MVCP, pressure was changed from the baseline case of 1 atm to 0.1 and 10 atm. In the high pressure MVCP case, the simulated flame is extinction-free, whereas in the low pressure MVCP case, the simulated flame features frequent extinction events and is close to global extinction. Results show that, despite its relative simplicity and provided that the global flame activation temperature is correctly calibrated, the AEA-based flame extinction criterion can accurately predict the simulated flame extinction events. It is also found that the AEA-based criterion provides predictions of flame extinction that are consistent with those provided by a CEMA-based criterion. This study supports the validity of a simple Damköhler-number-based criterion to predict flame extinction in engineering-level CFD models. © 2014 The Combustion Institute.

  20. Time resolved three-dimensional flamebase imaging of a lifted jet flame by laser scanning

    International Nuclear Information System (INIS)

    The measurement of flame surface evolution in both space and time is necessary for the advancement of knowledge concerning the physical processes contributing to lifted jet flame stabilisation. Previous studies either reproduce the flame front accurately in three-dimensional space or in time. In this study a measurement system capable of both is presented. Based on the Mie-scattering of oil droplets added to the jet flow, the system reconstructs the volumetric surface at the base of a lifted jet flame from a series of two-dimensional slices. The slices are created using a pulsed high-speed laser and a polygonal laser scanner unit which serves to sweep the laser beam through the measurement volume. A single high-speed camera is used for recording the subsequent measurement slices. The achieved temporal and spatial resolution as well as the accuracy and precision of the sheet placement are discussed in respect to the flames’ scales. The first results of the reconstruction of the lifted jet flame at its stabilisation point show the potential of such measurements to avoid the ambiguities in interpreting conventional 2D-data. (paper)

  1. Theory of DDT in unconfined flames

    CERN Document Server

    Khokhlov, A M; Wheeler, J C; Wheeler, J Craig

    1996-01-01

    This paper outlines a theoretical approach for predicting the onset of detonation in unconfined turbulent flames which is relevant both to problems of terrestrial combustion and to thermonuclear burning in Type Ia supernovae. Two basic assumuptions are made: 1) the gradient mechanism is the inherent mechanism that leads to DDT in unconfined conditions, and 2) the sole mechanism for preparing the gradient in induction time is by turbulent mixing and local flame quenching. The criterion for DDT is derived in terms of the one-dimensional detonation wave thickness, the laminar flame speed, and the laminar flame thickness in the reactive gas. This approach gives a lower-bound criterion for DDT for conditions where shock preheating, wall effects, and interactions with obstacles are absent. Regions in parameter space where unconfined DDT can and cannot occur are determined. A subsequent paper will address these issues specifically in the astrophysical context.

  2. Dynamics and structure of turbulent premixed flames

    Science.gov (United States)

    Bilger, R. W.; Swaminathan, N.; Ruetsch, G. R.; Smith, N. S. A.

    1995-01-01

    In earlier work (Mantel & Bilger, 1994) the structure of the turbulent premixed flame was investigated using statistics based on conditional averaging with the reaction progress variable as the conditioning variable. The DNS data base of Trouve and Poinsot (1994) was used in this investigation. Attention was focused on the conditional dissipation and conditional axial velocity in the flame with a view to modeling these quantities for use in the conditional moment closure (CMC) approach to analysis of kinetics in premixed flames (Bilger, 1993). Two remarkable findings were made: there was almost no acceleration of the axial velocity in the flame front itself; and the conditional scalar dissipation remained as high, or higher, than that found in laminar premixed flames. The first finding was surprising since in laminar flames all the fluid acceleration occurs through the flame front, and this could be expected also for turbulent premixed flames at the flamelet limit. The finding gave hope of inventing a new approach to the dynamics of turbulent premixed flames through use of rapid distortion theory or an unsteady Bernoulli equation. This could lead to a new second order closure for turbulent premixed flames. The second finding was contrary to our measurements with laser diagnostics in lean hydrocarbon flames where it is found that conditional scalar dissipation drops dramatically below that for laminar flamelets when the turbulence intensity becomes high. Such behavior was not explainable with a one-step kinetic model, even at non-unity Lewis number. It could be due to depletion of H2 from the reaction zone by preferential diffusion. The capacity of the flame to generate radicals is critically dependent on the levels of H2 present (Bilger, et al., 1991). It seemed that a DNS computation with a multistep reduced mechanism would be worthwhile if a way could be found to make this feasible. Truly innovative approaches to complex problems often come only when there is the

  3. Fuel properties to enable lifted-flame combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Eric [Ford Motor Company, Dearborn, MI (United States)

    2015-03-15

    The Fuel Properties to Enable Lifted-Flame Combustion project responded directly to solicitation DE-FOA-0000239 AOI 1A, Fuels and Lubricants for Advanced Combustion Regimes. This subtopic was intended to encompass clean and highly-efficient, liquid-fueled combustion engines to achieve extremely low engine-out nitrogen oxides (NOx) and particulate matter (PM) as a target and similar efficiency as state-of-the-art direct injection diesel engines. The intent of this project was to identify how fuel properties can be used to achieve controllable Leaner Lifted Flame Combustion (LLFC) with low NOx and PM emissions. Specifically, this project was expected to identify and test key fuel properties to enable LLFC and their compatibility with current fuel systems and to enhance combustion models to capture the effect of fuel properties on advanced combustion. Successful demonstration of LLFC may reduce the need for after treatment devices, thereby reducing costs and improving thermal efficiency. The project team consisted of key technical personnel from Ford Motor Company (FMC), the University of Wisconsin-Madison (UW), Sandia National Laboratories (SNL) and Lawrence Livermore National Laboratories (LLNL). Each partner had key roles in achieving project objectives. FMC investigated fuel properties relating to LLFC and sooting tendency. Together, FMC and UW developed and integrated 3D combustion models to capture fuel property combustion effects. FMC used these modeling results to develop a combustion system and define fuel properties to support a single-cylinder demonstration of fuel-enabled LLFC. UW investigated modeling the flame characteristics and emissions behavior of different fuels, including those with different cetane number and oxygen content. SNL led spray combustion experiments to quantify the effect of key fuel properties on combustion characteristics critical for LLFC, as well as single cylinder optical engine experiments to improve fundamental

  4. Effects of advanced treatment of municipal wastewater on the White River near Indianapolis, Indiana; trends in water quality, 1978-86

    Science.gov (United States)

    Crawford, Charles G.; Wangsness, David J.

    1993-01-01

    The City of Indianapolis has constructed state-of-the-art advanced municipal wastewater-treatment systems to enlarge and upgrade the existing secondary-treatment processes at its Belmont and Southport treatment plants. These new advanced-wastewater-treatment plants became operational in 1983. A nonparametric statistical procedure--a modified form of the Wilcoxon-Mann-Whitney rank-sum test--was used to test for trends in time-series water-quality data from four sites on the White River and from the Belmont and Southport wastewater-treatment plants. Time-series data representative of pre-advanced- (1978-1980) and post-advanced- (1983--86) wastewater-treatment conditions were tested for trends, and the results indicate substantial changes in water quality of treated effluent and of the White River downstream from Indianapolis after implementation of advanced wastewater treatment. Water quality from 1981 through 1982 was highly variable due to plant construction. Therefore, this time period was excluded from the analysis. Water quality at sample sites located upstream from the wastewater-treatment plants was relatively constant during the period of study (1978-86). Analysis of data from the two plants and downstream from the plants indicates statistically significant decreasing trends in effluent concentrations of total ammonia, 5-day biochemical-oxygen demand, fecal-coliform bacteria, total phosphate, and total solids at all sites where sufficient data were available for testing. Because of in-plant nitrification, increases in nitrate concentration were statistically significant in the two plants and in the White River. The decrease in ammonia concentrations and 5-day biochemical-oxygen demand in the White River resulted in a statistically significant increasing trend in dissolved-oxygen concentration in the river because of reduced oxygen demand for nitrification and biochemical oxidation processes. Following implementation of advanced wastewater treatment, the

  5. Flame four-dimensional deflection tomography with compressed-sensing-revision reconstruction

    Science.gov (United States)

    Zhang, Bin; Zhao, Minmin; Liu, Zhigang; Wu, Zhaohang

    2016-08-01

    Deflection tomography with limited angle projections was investigated to visualize a premixed flame. A projection sampling system for deflection tomography was used to obtain chronological deflectogram arrays at six view angles with only a pair of gratings. A new iterative reconstruction algorithm with deflection angle compressed-sensing revision was developed to improve reconstruction-distribution quality from incomplete projection data. Numerical simulation and error analysis provided a good indication of algorithm precision and convergence. In the experiment, 150 fringes were processed, and temperature distributions in 20 cross-sections were reconstructed from projection data in four instants. Four-dimensional flame structures and temperature distributions in the flame interior were visualized using the visualization toolkit. The experimental reconstruction was then compared with the result obtained from computational fluid dynamic analysis.

  6. NO concentration imaging in turbulent nonpremixed flames

    Energy Technology Data Exchange (ETDEWEB)

    Schefer, R.W. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The importance of NO as a pollutant species is well known. An understanding of the formation characteristics of NO in turbulent hydrocarbon flames is important to both the desired reduction of pollutant emissions and the validation of proposed models for turbulent reacting flows. Of particular interest is the relationship between NO formation and the local flame zone, in which the fuel is oxidized and primary heat release occurs. Planar imaging of NO provides the multipoint statistics needed to relate NO formation to the both the flame zone and the local turbulence characteristics. Planar imaging of NO has been demonstrated in turbulent flames where NO was seeded into the flow at high concentrations (2000 ppm) to determine the gas temperature distribution. The NO concentrations in these experiments were significantly higher than those expected in typical hydrocarbon-air flames, which require a much lower detectability limit for NO measurements. An imaging technique based on laser-induced fluorescence with sufficient sensitivity to study the NO formation mechanism in the stabilization region of turbulent lifted-jet methane flames.

  7. Recent advances in the development of quality protein maize germplasm at the Centro International de Mejoramiento de Maiz y Trigo

    International Nuclear Information System (INIS)

    The paper reviews past difficulties in the acceptance of quality protein maize (QPM) materials by farmers because of several crucial problems plaguing these materials. The breeding strategy used at the Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT) over the past several years is described in detail. The strategy is based on the combined use of two genetic systems involving the opaque-2 gene and genetic modifiers. Inheritance of modifiers, some considerations in the exploitation and their role in circumventing the problems facing QPM materials are discussed. Progress is reported in overcoming the problems of yield, seed appearance, ear rot and the dry-down ability in QPM materials. Using hard endosperm QPM donor stocks, a wide array of QPM germplasm has been developed through the conversion programme and the development of QPM gene pools. To make the best use of available QPM germplasm, the current efforts in the management and handling of the germplasm are outlined. In the back-up stages, eight tropical and six subtropical QPM pools will be handled. In addition, six tropical and four subtropical advanced QPM populations were formed. These will be subjected to a rigorous international progency testing programme for improved yield, general adaptation and the stability of modifiers. Experimental data from international tests are presented, indicating the superior performance of several QPM materials. The objectives of some exploratory projects in QPM research are explained. Renewed interest in QPM research is being shown and the outlook for commercial exploitation of QPM materials in some countries seems very promising. (author)

  8. Temperature imaging of turbulent dilute spray flames using two-line atomic fluorescence

    Science.gov (United States)

    Medwell, Paul R.; Masri, Assaad R.; Pham, Phuong X.; Dally, Bassam B.; Nathan, Graham J.

    2014-11-01

    This paper reports the first application of nonlinear excitation regime two-line atomic fluorescence imaging (NTLAF) of indium to measure temperature in turbulent flames of dilute sprays. Indium chloride is dissolved in acetone fuel which is atomised with an ultrasonic nebuliser and supplied with carrier air into a standard piloted burner. It is found that the indium fluorescence signal is not affected by scattering from the droplets or fuel vapour and that no changes to the optical arrangement used with gaseous flames were required. Notwithstanding the lower temperature thresholds of 800 K imposed by the population of excitation species for the NTLAF method and of 1,200 K imposed by the mechanism of releasing gas-phase indium from its salt, the comparisons of conditional and pseudo-unconditional means with thermocouple measurements performed in a range of turbulent spray flames are quite favourable. The NTLAF signal quality deteriorates on the jet centreline at upstream locations and on the lean side of the flame, the former being largely due to insufficient conversion of indium chloride to indium atoms and the latter potentially due to indium oxidation. Nevertheless, the signal-to-noise ratios obtained in the reaction zone regions are good and the results reveal the expected temperature trends in the turbulent spray flames tested here. Further developments are necessary to resolve the mechanism of indium formation and to broaden the temperature range.

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

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-01-01

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

  10. The Linear Instability of Astrophysical Flames in Magnetic Fields

    CERN Document Server

    Dursi, L J

    2004-01-01

    Supernovae of Type Ia are used as standard candles for cosmological observations despite the as yet incomplete understanding of their explosion mechanism. In one model, these events are thought to result from subsonic burning in the core of an accreting Carbon/Oxygen white dwarf that is accelerated through flame wrinkling and flame instabilities. Many such white dwarfs have significant magnetic fields. Here we derive the linear effects of such magnetic fields on one flame instability, the well-known Landau-Darrieus instability. When the magnetic field is strong enough that the flame is everywhere sub-Alfvenic, the instability can be greatly suppressed. Super-Alfvenic flames are much less affected by the field, with flames propagating parallel to the field somewh at destabilized, and flames propagating perpendicular to the field somewhat stabili zed. Trans-Alfvenic parallel flames, however, like trans-Alfvenic parallel shocks, are seen to be non-evolutionary; understanding the behavior of these flames will req...

  11. Propagation and stability of expanding spherical flames

    Science.gov (United States)

    Jomaas, Grunde

    High-fidelity experiments were conducted to determine the laminar flame speeds of various fuels, to define the transition boundaries of both cellular and spiral flame front instabilities that develop over the flame surface, and to determine the cellular flame acceleration constants for outwardly propagating spherical flames in a near-constant pressure environment up to 60 atmospheres. The flame front movement was monitored using schlieren cinematography and recorded with a high-speed digital camera. Experiments were conducted for a wide range of pressures and equivalence ratios to yield flame speed data for acetylene, ethylene, ethane, propylene, propane, dimethyl ether, and hydrogen/carbon monoxide in air. These data were post-processed in order to account for stretch effects, yielding laminar, unstretched flame speeds and Markstein lengths. The results were compared with existing chemical kinetics mechanisms and used to suggest improvements. The instant of transition to cellularity was experimentally determined for various fuels and fuel mixtures and subsequently interpreted on the basis of hydrodynamic and diffusional-thermal instabilities. Experimental results show that the transition Peclet number, Pec = Rc/ℓL, assumes an almost constant value for the near-equidiffusive acetylene and ethylene flames with wide ranges in the mixture stoichiometry, oxygen concentration, and pressure, where Rc is the flame radius at transition and ℓL the laminar flame thickness. However, for the non-equidiffusive hydrogen and propane flames, Pec respectively increases and decreases somewhat linearly with the mixture equivalence ratio. Evaluation of Pec using the theory of Bechtold and Matalon show complete qualitative agreement and satisfactory quantitative agreement, demonstrating the insensitivity of Pec to all system parameters for equidiffusive mixtures, and the dominance of the Markstein number, Ze(Le-1), in destabilization for non-equidiffusive mixtures, where Ze is the

  12. Flame attenuation effects on surface temperature measurements using IR thermography

    Science.gov (United States)

    de Vries, Jaap; Tabinowski, Robert

    2016-05-01

    Long-wave infrared (LWIR) cameras provide the unique ability to see through smoke and condensed water vapor. However, soot generated inside the flame does attenuate the LWIR signal. This work focuses on gas flame attenuation effects of LWIR signals originating from a blackbody. The experimental setup consists of time averaged, laboratory-scale turbulent diffusion flames with heat release rates set at 5 kW, 10 kW, and 15 kW. Propylene and ethylene were used as fuel, providing two different soot yields. A 30 cm by 30 cm blackbody was used with maximum surface temperatures set to 600°C. Both instantaneous and time-averaged blackbody temperature profiles through the flame were measured using a LWIR microbolometer camera (7.5-14 μm). Flame intermittency was quantified by color segmenting visible images. The experiments showed that low blackbody temperatures were significantly affected by the presence of the flame. At 600°C, the effect of flame absorption matches the emitted radiation from the flame itself. Using data obtained at various blackbody temperatures, the flame transmittance was obtained using a Generalized Reduced Gradient optimization method. The transmittance was lower for propylene flames compared to ethylene flames. Ethylene flames were shown to have higher temperatures. Using the values for flame radiance and transmissivity, the total averaged radiance of the flame plus the blackbody could be reproduced with 1% accuracy.

  13. Effect of Dimethyl Ether Mixing on Soot Size Distribution in Premixed Ethylene Flame

    KAUST Repository

    Li, Zepeng

    2016-04-21

    As a byproduct of incomplete combustion, soot attracts increasing attentions as extensive researches exploring serious health and environmental effects from soot particles. Soot emission reduction requires a comprehensive understanding of the mechanism for polycyclic aromatic hydrocarbons and of soot formation and aging processes. Therefore, advanced experimental techniques and numerical simulations have been conducted to investigate this procedure. In order to investigate the effects of dimethyl ether (DME) mixing on soot particle size distribution functions (PSDFs), DME was mixed in premixed ethylene/oxygen/argon at flames at the equivalence ratio of 2.0 with a range of mixing ratio from 0% to 30% of the total carbon fed. Two series of atmospheric pressure flames were tested in which cold gas velocity was varied to obtain different flame temperatures. The evolution of PSDFs along the centerline of the flame was determined by burner stabilized stagnation probe and scanning mobility particle sizer (SMPS) techniques, yielding the PSDFs for various separation distances above the burner surface. Meanwhile, the flame temperature profiles were carefully measured by a thermocouple and the comparison to that of simulated laminar premixed burner-stabilized stagnation flame was satisfactory. Additionally, to understand the chemical role of DME mixing in soot properties, characterization measurements were conducted on soot samples using thermo-gravimetric analysis (TGA) and elemental analysis (EA). Results of the evolution of PSDFs and soot volume fraction showed that adding DME into ethylene flame could reduce soot yield significantly. The addition of DME led to the decrease of both the soot nucleation rate and the particle mass growth rate. To explain the possible mechanism for the observation, numerical simulations were performed. Although DME addition resulted in the slight increase of methyl radicals from pyrolysis, the decrease in acetylene and propargyl radicals

  14. Autoignition and flame stabilisation processes in turbulent non-premixed hot coflow flames

    NARCIS (Netherlands)

    Oldenhof , E.

    2012-01-01

    This dissertation examines stabilisation processes in turbulent non-premixed jet flames, created by injecting gaseous fuel into a co-flowing stream of hot, low-oxygen combustion products. Being able to predict whether and how a flame achieves stable and reliable combustion is a matter of great pract

  15. On the dynamics of flame edges in diffusion-flame/vortex interactions

    Energy Technology Data Exchange (ETDEWEB)

    Hermanns, Miguel; Linan, Amable [Departamento de Motopropulsion y Termofluidodinamica, Universidad Politecnica de Madrid, Pza. Cardenal Cisneros 3, 28040 Madrid (Spain); Vera, Marcos [Area de Mecanica de Fluidos, Universidad Carlos III de Madrid, 28911 Leganes (Spain)

    2007-04-15

    We analyze the local flame extinction and reignition of a counterflow diffusion flame perturbed by a laminar vortex ring. Local flame extinction leads to the appearance of flame edges separating the burning and extinguished regions of the distorted mixing layer. The dynamics of these edges is modeled based on previous numerical results, with heat release effects fully taken into account, which provide the propagation velocity of triple and edge flames in terms of the upstream unperturbed value of the scalar dissipation. The temporal evolution of the mixing layer is determined using the classical mixture fraction approach, with both unsteady and curvature effects taken into account. Although variable density effects play an important role in exothermic reacting mixing layers, in this paper the description of the mixing layer is carried out using the constant density approximation, leading to a simplified analytical description of the flow field. The mathematical model reveals the relevant nondimensional parameters governing diffusion-flame/vortex interactions and provides the parameter range for the more relevant regime of local flame extinction followed by reignition via flame edges. Despite the simplicity of the model, the results show very good agreement with previously published experimental results. (author)

  16. Combustion Synthesis of Nanomaterials Using Various Flame Configurations

    KAUST Repository

    Ismail, Mohamed Anwar

    2016-02-01

    Titanium dioxide (TiO2) is an important semiconducting metal oxide and is expected to play an important role in future applications related to photonic crystals, energy storage, and photocatalysis. Two aspects regarding the combustion synthesis have been investigated; scale-up in laboratory synthesis and advanced nanoparticle synthesis. Concerning the scale-up issue, a novel curved wall-jet (CWJ) burner was designed for flame synthesis. This was achieved by injecting precursors of TiO2 through a central port into different flames zones that were stabilized by supplying fuel/air mixtures as an annular-inward jet over the curved wall. This provides a rapid mixing of precursors in the reaction zone with hot products. In order to increase the contact surface between the precursor and reactants as well as its residence time within the hot products, we proposed two different modifications. The CWJ burner was modified by adding a poppet valve on top of the central port to deliver the precursor tangentially into the recirculating flow upstream within the recirculation zone. Another modification was made by adopting double-slit curved wall-jet (DS-CWJ) configuration, one for the reacting mixture and the other for the precursor instead of the central port. Particle growth of titanium dioxide (TiO2) nanoparticles and their phases were investigated. Ethylene (C2H4), propane (C3H8), and methane (CH4) were used with varying equivalence ratio and Reynolds number and titanium tetraisopropoxide (TTIP) was the precursor. Flow field and flame structure were quantified using particle image velocimetry (PIV) and OH planar laser-induced fluorescence (PLIF) techniques, respectively. TiO2 nanoparticles were characterized using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Raman Spectroscopy, and BET nitrogen adsorption for surface area analysis. The flow field quantified by PIV consisted of a wall-jet region leading to a recirculation zone, an

  17. Turbulence-flame interactions in DNS of a laboratory high Karlovitz premixed turbulent jet flame

    Science.gov (United States)

    Wang, Haiou; Hawkes, Evatt R.; Chen, Jacqueline H.

    2016-09-01

    In the present work, direct numerical simulation (DNS) of a laboratory premixed turbulent jet flame was performed to study turbulence-flame interactions. The turbulent flame features moderate Reynolds number and high Karlovitz number (Ka). The orientations of the flame normal vector n, the vorticity vector ω and the principal strain rate eigenvectors ei are examined. The in-plane and out-of-plane angles are introduced to quantify the vector orientations, which also measure the flame geometry and the vortical structures. A general observation is that the distributions of these angles are more isotropic downstream as the flame and the flow become more developed. The out-of-plane angle of the flame normal vector, β, is a key parameter in developing the correction of 2D measurements to estimate the corresponding 3D quantities. The DNS results show that the correction factor is unity at the inlet and approaches its theoretical value of an isotropic distribution downstream. The alignment characteristics of n, ω and ei, which reflect the interactions of turbulence and flame, are also studied. Similar to a passive scalar gradient in non-reacting flows, the flame normal has a tendency to align with the most compressive strain rate, e3, in the flame, indicating that turbulence contributes to the production of scalar gradient. The vorticity dynamics are examined via the vortex stretching term, which was found to be the predominant source of vorticity generation balanced by dissipation, in the enstrophy transport equation. It is found that although the vorticity preferentially aligns with the intermediate strain rate, e2, the contribution of the most extensive strain rate, e1, to vortex stretching is comparable with that of the intermediate strain rate, e2. This is because the eigenvalue of the most extensive strain rate, λ1, is always large and positive. It is confirmed that the vorticity vector is preferentially positioned along the flame tangential plane, contributing

  18. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    International Nuclear Information System (INIS)

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO2) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents

  19. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    Energy Technology Data Exchange (ETDEWEB)

    T. Scott Hickman; James J. Justice

    2001-06-16

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO{sub 2}) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents.

  20. Engineering Flame Retardant Biodegradable Nanocomposites

    Science.gov (United States)

    He, Shan; Yang, Kai; Guo, Yichen; Zhang, Linxi; Pack, Seongchan; Davis, Rachel; Lewin, Menahem; Ade, Harald; Korach, Chad; Kashiwagi, Takashi; Rafailovich, Miriam

    2013-03-01

    Cellulose-based PLA/PBAT polymer blends can potentially be a promising class of biodegradable nanocomposites. Adding cellulose fiber reinforcement can improve mechanical properties of biodegradable plastics, but homogeneously dispersing hydrophilic cellulose in the hydrophobic polymer matrix poses a significant challenge. We here show that resorcinol diphenyl phosphates (RDP) can be used to modify the surface energy, not only reducing phase separation between two polymer kinds but also allowing the cellulose particles and the Halloysite clay to be easily dispersed within polymer matrices to achieve synergy effect using melt blending. Here in this study we describe the use of cellulose fiber and Halloysite clay, coated with RDP surfactant, in producing the flame retardant polymer blends of PBAT(Ecoflex) and PLA which can pass the stringent UL-94 V0 test. We also utilized FTIR, SEM and AFM nanoindentation to elucidate the role RDP plays in improving the compatibility of biodegradable polymers, and to determine structure property of chars that resulted in composites that could have optimized mechanical and thermal properties. Supported by Garcia Polymer Center and NSF Foundation.

  1. A, a Brominated Flame Retardant

    Directory of Open Access Journals (Sweden)

    Tomomi Takeshita

    2013-01-01

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

  2. Assessment of quality of life in patients with advanced non-small cell lung carcinoma treated with a combination of carboplatin and paclitaxel

    Directory of Open Access Journals (Sweden)

    Camila Uanne Resende Avelino

    2015-04-01

    Full Text Available OBJECTIVE: Non-small cell lung carcinoma (NSCLC is the most common type of lung cancer. Most patients are diagnosed at an advanced stage, palliative chemotherapy therefore being the only treatment option. This study was aimed at evaluating the health-related quality of life (HRQoL of advanced-stage NSCLC patients receiving palliative chemotherapy with carboplatin and paclitaxel. METHODS: This was a multiple case study of advanced-stage NSCLC outpatients receiving chemotherapy at a public hospital in Rio de Janeiro, Brazil. The European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire was used in conjunction with its supplemental lung cancer-specific module in order to assess HRQoL. RESULTS: Physical and cognitive functioning scale scores differed significantly among chemotherapy cycles, indicating improved and worsened HRQoL, respectively. The differences regarding the scores for pain, loss of appetite, chest pain, and arm/shoulder pain indicated improved HRQoL. CONCLUSIONS: Chemotherapy was found to improve certain aspects of HRQoL in patients with advanced-stage NSCLC.

  3. Second Law Analysis of Diffusion Flames

    Directory of Open Access Journals (Sweden)

    Yalcin Gogus

    2001-03-01

    Full Text Available The objective of this paper is to investigate the sources of volumetric irreversibilities in both laminar and turbulent diffusion flames. The theoretical background of analysis relies on the local exergy transport equation, which allows the microscopic formulation of the well-known Gouy-Stodola theorem. For laminar reacting flows, the volumetric entropy generation rate expression includes the viscous, thermal, diffusion and chemical components. Their expressions show that the corresponding irreversibilities are uncoupled if the combustion process occurs at constant pressure. The numerical simulation of a methane-air combustion process shows that the thermal, chemical and diffusive irreversibilities represent, in order of enumeration, the predominant irreversibilities in the laminar diffusion reacting flows. In the case of turbulent diffusion flames, the viscous, thermal, diffusion and chemical mean components have to be expressed in accordance with the combustion model. Two combustion models are used: the multi-species approach based on the eddy-break formulation of mean reaction rate, and the assumed probability density function for a conserved scalar that relies on the flame sheet model. For a diffusion methane-air jet flame, the distribution of mean irreversibility components is presented. Taking into account the technical importance of diffusion flames, the analysis could serve to improve the combustion geometry and the flow condition.

  4. Distributed Flames in Type Ia Supernovae

    CERN Document Server

    Aspden, A J; Woosley, S E; 10.1088/0004-637X/710/2/1654

    2011-01-01

    In the distributed burning regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning depends on the turbulent Damkohler number (Da), which steadily declines from much greater than one to less that one as the density decreases to a few 10^6 g/cc. Scaling arguments predict that the turbulent flame speed s, normalized by the turbulent intensity u, follows s/u=Da^1/2 for Da1, and that localized excursions to as much as five times u can occur. The lambda-flame speed and width can be predicted based on the turbulence in the star and the turbulent nuclear burning time scale of the fuel. We propose a practical method for measuring these based on the scaling relations and small-scale computationally-inexpensive simulations. This suggests that a simple turbulent flame model can be easily constructed suitable for large-scale distributed supernovae flames.

  5. Chaotic radiation/turbulence interactions in flames

    Energy Technology Data Exchange (ETDEWEB)

    Menguec, M.P.; McDonough, J.M.

    1998-11-01

    In this paper, the authors present a review of their recent efforts to model chaotic radiation-turbulence interactions in flames. The main focus is to characterize soot volume fraction fluctuations in turbulent diffusion flames, as they strongly contribute to these interaction. The approach is based on the hypothesis that the fluctuations of properties in turbulent flames are deterministic in nature, rather than random. The authors first discuss the theoretical details and then they briefly outline the experiments conducted to measure the scattered light signals from fluctuating soot particles along the axis of an ethylene-air diffusion flame. They compare the power spectra and time series obtained from experiments against the ad-hoc and rigorous models derived using a series of logistic maps. These logistic maps can be used in simulation of the fluctuations in these type of flames, without extensive computational effort or sacrifice of physical detail. Availability of accurate models of these kinds allows investigation of radiation-turbulence interactions at a more fundamental level than it was previously possible.

  6. Quality of life and management project for patients with advanced lung cancer%晚期肺癌生活质量与治疗方案选择

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Compared with best supportive care,chemotherapy can prolong survival and improve quality of life,and symptoms associated with society activities and disease.Chemotherapy can improve quality of life of patients with effective treatment and stable treatment. Treatment benefit was often underestimated using clinical relief rate,so which should not chosen as index for evaluating effect of palliative treatment. So for patients with poor status ,and objective of relieving symptoms,short term,low dose chemotherapy should be suggested due to its characteristic of low cost,short inhospitalization time,and favorable improvement of quality of life. For patients with good condition in limited advanced stage,radical treatment is objective,and hence single chemotherapy of standard dose or chemotherapy combining radiotherapy should be suggested.

  7. Pulsating instability and self-acceleration of fast turbulent flames

    CERN Document Server

    Poludnenko, A Y

    2015-01-01

    (Abridged) A series of three-dimensional numerical simulations is used to study the intrinsic stability of high-speed turbulent flames. Calculations model the interaction of a fully-resolved premixed flame with a highly subsonic, statistically steady, homogeneous, isotropic turbulence. We consider a wide range of turbulent intensities and system sizes, corresponding to the Damk\\"ohler numbers Da = 0.1-6.0. These calculations show that turbulent flames in the regimes considered are intrinsically unstable. In particular, we find three effects. 1) Turbulent flame speed develops pulsations with the observed peak-to-peak amplitude > 10 and a characteristic time scale close to a large-scale eddy turnover time. Such variability is caused by the interplay between turbulence, which continuously creates the flame surface, and highly intermittent flame collisions, which consume the flame surface. 2) Unstable burning results in the periodic pressure build-up and the formation of pressure waves or shocks, when the flame s...

  8. MODELING OF TURBULENT FLAME VELOCITY FOR SPARK IGNITION ENGINES

    Directory of Open Access Journals (Sweden)

    RASHID ALI,

    2011-04-01

    Full Text Available The present model reported a comprehensive theoretical study on flame velocity in spark ignition engine for iso-octane air mixture. The present model developed is a zero-dimensional thermodynamicmodel. Computer simulations have been performed for the turbulent flame velocity of premixed flame. The comparison has been made between the flame velocity obtained from the present model to thetheoretical and experimental flame velocities that are available in the literature for the wide range of engine operating parameters such as clearance height, density ratio, equivalence ratio, flame radius,engine speed and unburnt mixture temperature. The comparison shows a good agreement between the flame velocity obtained from the present model with the experimental and theoretical flame velocity of Cakir.

  9. EFFECT OF ORGANOPHOSPHORUS FLAME RETARDANTS ON NEURONAL DEVELOPMENT IN VITRO

    Science.gov (United States)

    The increased use of organophosphorus compounds as alternatives to brominated flame retardants (BFRs) has led to widespread human exposure, There is, however, limited information on their potential health effects. This study compared the effects of nii ne organophosphorus flame...

  10. Beam steering effects in turbulent high pressure flames

    Energy Technology Data Exchange (ETDEWEB)

    Hemmerling, B.; Kaeppeli, B. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    The propagation of a laser beam through a flame is influenced by variations of the optical density. Especially in turbulent high pressure flames this may seriously limit the use of laser diagnostic methods. (author) 1 fig., 2 refs.

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

    OpenAIRE

    2014-01-01

    Improving the compatibility between flame retardant and asphalt is a difficult task due to the complex nature of the materials. This study explores a low dosage compound flame retardant and seeks to improve the compatibility between flame retardants and asphalt. An orthogonal experiment was designed taking magnesium hydroxide, ammonium polyphosphate, and melamine as factors. The oil absorption and activation index were tested to determine the effect of titanate on the flame retardant additive...

  12. AC Electric Fields Drive Steady Flows in Flames

    OpenAIRE

    Drews, Aaron M.; Cademartiri, Ludovico; Chemama, Michael Leopold; Brenner, Michael P.; Whitesides, George M.; Bishop, Kyle J. M.

    2012-01-01

    We show that time-oscillating electric fields applied to plasmas present in flames create steady flows of gas. Ions generated within the flame move in the field and migrate a distance δ before recombining; the net flow of ions away from the flame creates a time-averaged force that drives the steady flows observed experimentally. A quantitative model describes the response of the flame and reveals how δ decreases as the frequency of the applied field increases. Interestingly, above a critical ...

  13. Luminous Flame Temperature Distribution Measurement Using the Emission Method

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Flame temperature distribution is one of the most important characteristic parameters in combustion research. The emission method is a good way to measure the luminous flame temperature field. The maximum entropy method is introduced to the temperature distribution measurement of a luminous flame using the emission method. A simplified mathematical model was derived by combining the thermal radiation theory, reconstruction algorithm and maximum entropy method. Suitable parameters were selected in the computing process. Good experimental results were obtained with pulverized coal flames.

  14. Annealing effect and stability of carbon nanotubes in hydrogen flame

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Annealing of carbon nanotubes (CNTs) by the hydrogen flame in air was investigated in this study. Raman spectroscopy and scanning electron microscopy were used to characterize the products. The peak width of Raman spectra decreased with the increase in the annealing time. The CNTs were not stable in the hydrogen flame and the etching rate of the CNTs by hydrogen flame was very high. The hydrogen flame annealing had some effects on improving the crystallinity of CNTs.

  15. The Influences of Electric Fields on Soot Formation and Flame Structure of Diffusion Flames

    Institute of Scientific and Technical Information of China (English)

    LinXie; TakeyukiKishi; 等

    1993-01-01

    The influences of DC and AC electric fields,at frequencies up to 1.48 MHz and the maximum strength of about 6 kV/cm,on soot formation and flame structure were investigated using a counterflow type acetylene diffusion flame.The distributioons of flame luminosity,soot volume fraction,Flame temperature and OH concentration in flame were measured by non-invasive detection methods.Under the influence of electric fields,the changes in distribution of the soot volume fraction were confirmed.Electric fields of high frequency and high intensity reduced the soot volume fraction.whereas other electric fields increased it.The maximum values of flame temperature and OH concentration decreased.In the relationship between the maximum value of the soot volume fraction and the maximum temperature,the maximum soot volum fraction showed toth increase and decrease with maximum temperatures depending on the frequencies and intensities of the electric fields,and both of them occurred at temperatures lower than 1990 K.The production of the incipient particles seemed to be the dominant process controlling the soot volume fraction due to the electric fields.The luminosity of a sooting diffusion flame was found to depend on the volume fraction and temperature of the soot particles in the flame,As for the behavior of the flame in the electric fields.the ionic wind effect was not found to be dominant in the present work,and the result of the precious simulation based on the ionic wind theory was not consistent with the present experimental results.

  16. The Flame Challenge and Communicating Science

    Science.gov (United States)

    Ames, Ben

    2013-04-01

    When famed actor and science enthusiast Alan Alda was 11 years-old he was itching to know the science behind a flame. He asked his science teacher but her blunt response didn't exactly satisfy his curiosity. ``It's oxidation,'' she said. 65 years later, Alan Alda launched ``The Flame Challenge,'' an annual contest encouraging scientists to improve their communication to the general public. In this talk, last year's winner discusses his approach to successfully explaining the science behind a flame to a wide audience. Because communicating science is a pillar of the scientific method, he shares key elements of successful communication important for engaging funders, policy-makers, students, the general public, and even other scientists.

  17. Polybrominated diphenyl ethers and novel flame retardants

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Vorkamp, Katrin; Nielsen, Jesper Bo;

    ]. Recent results from Sweden indicated that dust was a significant source of exposure for the octa- to decabrominated congeners in particular [3]. Moreover, several novel flame retardants (NFRs) have been detected in dust some of which might be replacement products of PBDEs [4]. Building on these findings...... blood plasma and associations with house dust in a Danish cohort. Int. J. Hyg. Environ. Health 213, 233-242. [3] Sahlström L.M.O., Sellström U., de Wit C.A., Lignell S., Darnerud P.O. (2015). Estimated intakes of brominated flame retardants via diet and dust compared to internal concentrations...... in a Swedish mother-toddler cohort. Int. J. Hyg. Environ. Health 218, 422-432. [4] Ali N., Harrad S., Goosey E., Neels H., Covaci A. (2011). “Novel” brominated flame retardants in Belgian and UK indoor dust: Implications for human exposure. Chemosphere 83, 1360-1365. [5] Vorkamp K., Thomsen M., Frederiksen M...

  18. Different spreading regimes of spray-flames

    Science.gov (United States)

    Suard, Sylvain; Haldenwang, Pierre; Nicoli, Colette

    2004-05-01

    We present a minimal model of spray combustion to investigate a flame front propagating through a fuel-lean mixture of fuel vapor, droplets and air. The model relies on a main control parameter, Da, named the Damkoehler number, which allows us to take into account a large variety of fuel sprays. Numerical results reveal, as a function of Da, a wide range of spray-flame structures, including the classical gaseous premixed flame, a specific regime controlled by vaporisation, and a pulsating mode of propagation. The latter appears when the vaporisation is smaller than (or equal to) the reaction time, and it occurs even with a unit Lewis number. To cite this article: S. Suard et al., C. R. Mecanique 332 (2004).

  19. Numerical modelling of ion transport in flames

    KAUST Repository

    Han, Jie

    2015-10-20

    This paper presents a modelling framework to compute the diffusivity and mobility of ions in flames. The (n, 6, 4) interaction potential is adopted to model collisions between neutral and charged species. All required parameters in the potential are related to the polarizability of the species pair via semi-empirical formulas, which are derived using the most recently published data or best estimates. The resulting framework permits computation of the transport coefficients of any ion found in a hydrocarbon flame. The accuracy of the proposed method is evaluated by comparing its predictions with experimental data on the mobility of selected ions in single-component neutral gases. Based on this analysis, the value of a model constant available in the literature is modified in order to improve the model\\'s predictions. The newly determined ion transport coefficients are used as part of a previously developed numerical approach to compute the distribution of charged species in a freely propagating premixed lean CH4/O2 flame. Since a significant scatter of polarizability data exists in the literature, the effects of changes in polarizability on ion transport properties and the spatial distribution of ions in flames are explored. Our analysis shows that changes in polarizability propagate with decreasing effect from binary transport coefficients to species number densities. We conclude that the chosen polarizability value has a limited effect on the ion distribution in freely propagating flames. We expect that the modelling framework proposed here will benefit future efforts in modelling the effect of external voltages on flames. Supplemental data for this article can be accessed at http://dx.doi.org/10.1080/13647830.2015.1090018. © 2015 Taylor & Francis.

  20. 30 CFR 56.7805 - Smoking and open flames.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Smoking and open flames. 56.7805 Section 56... Jet Piercing Rotary Jet Piercing § 56.7805 Smoking and open flames. Persons shall not smoke and open... smoking and open flames shall be posted in these areas....

  1. 30 CFR 57.7805 - Smoking and open flames.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Smoking and open flames. 57.7805 Section 57... Rotary Jet Piercing Rotary Jet Piercing-Surface Only § 57.7805 Smoking and open flames. Persons shall not... warning against smoking and open flames shall be posted in these areas....

  2. 30 CFR 56.6904 - Smoking and open flames.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Smoking and open flames. 56.6904 Section 56.6904 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Requirements § 56.6904 Smoking and open flames. Smoking and use of open flames shall not be permitted within...

  3. STUDIES OF PHYSICAL MECHANISMS IN LASER ENHANCED IONIZATION IN FLAMES

    OpenAIRE

    Schenck, P.; Travis, J.; Turk, G

    1983-01-01

    Laser enhanced ionization (LEI) mechanisms which result in locally large neutral atom depletions in flames are discussed. In addition, this results in a locally large perturbation of the ionization rate of the flame can be observed by an imaging technique. Two theoretical models of the physical motion of the LEI electrons and ions in the flame and their applicability to experimental observations are discussed.

  4. Flame-Vortex Interactions Imaged in Microgravity - To Assess the Theory Flame Stretch

    Science.gov (United States)

    Driscoll, James F.

    2001-01-01

    The goals of this research are to: 1) Assess the Theory of Flame Stretch by operating a unique flame-vortex experiment under microgravity conditions in the NASA Glenn 2.2 Second Drop Tower (drops to identify operating conditions have been completed); 2) Obtain high speed shadowgraph images (500-1000 frames/s) using the drop rig (images were obtained at one-g, and the NASA Kodak RO camera is being mounted on the drop rig); 3) Obtain shadowgraph and PIV images at 1-g while varying the effects of buoyancy by controlling the Froude number (completed); 4) Numerically model the inwardly-propagating spherical flame that is observed in the experiment using full chemistry and the RUN 1DL code (completed); 5) Send images of the flame shape to Dr. G. Patniak at NRL who is numerically simulating the entire flame-vortex interaction of the present experiment (data transfer completed); and 6) Assess the feasibility of obtaining PIV velocity field images in the drop rig, which would be useful (but not required) for our assessment of the Theory of Flame Stretch (PIV images were obtained at one-g using same low laser power that is available from fiber optic cable in drop tower). The motivation for the work is to obtain novel measurement needed to develop a physically accurate model of turbulent combustion that can help in the control of engine pollutants. The unique experiment allows, for the first time, the detailed study of a negatively-curved (negatively stretched) flame, which is one of the five fundamental types of premixed flames. While there have been studies of flat flames, positively-curved (outwardly-propagating) cases and positively-strained (counterflow) cases, this is the first detailed study of a negatively-curved (inwardly-propagating) flame. The first set of drops in the 2.2 Second Drop Tower showed that microgravity provides more favorable conditions for achieving inwardly-propagating flames (IPFs) than 1-g. A vortex interacts with a flame and creates a spherical

  5. Pdf prediction of supersonic hydrogen flames

    Science.gov (United States)

    Eifler, P.; Kollmann, W.

    1993-01-01

    A hybrid method for the prediction of supersonic turbulent flows with combustion is developed consisting of a second order closure for the velocity field and a multi-scalar pdf method for the local thermodynamic state. It is shown that for non-premixed flames and chemical equilibrium mixture fraction, the logarithm of the (dimensionless) density, internal energy per unit mass and the divergence of the velocity have several advantages over other sets of scalars. The closure model is applied to a supersonic non-premixed flame burning hydrogen with air supplied by a supersonic coflow and the results are compared with a limited set of experimental data.

  6. Computatonal and experimental study of laminar flames

    Energy Technology Data Exchange (ETDEWEB)

    Smooke, M.D.; Long, M.B. [Yale Univ., New Haven, CT (United States)

    1993-12-01

    This research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in counterflow, cylindrical and coflowing axisymmetric configurations. The authors have pursued both computational and experimental aspects of the research in parallel. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the one and two-dimensional nonlinear boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. In particular, spontaneous Raman scattering and laser induced fluorescence were used to measure the temperature, major and minor species profiles.

  7. Synthesis of Nano-Particles in Flames

    DEFF Research Database (Denmark)

    Johannessen, Tue

    The scope of this work is to investigate the synthesis of aluminum oxide particles in flames from the combustion of an aluminum alkoxide precursor.A general introduction to particles formation in the gas phase is presented with emphasis on the mechanisms that control the particle morphology after...... energy expression.Furthermore, the model is validated by comparison with experimental data of the flame synthesis of titania by combustion of TiCl4 previously presented by Pratsinis et al. (1996).The combination of particle dynamics and CFD simulations has proved to be an efficient method...

  8. Adiabatic Flame Temperature for Combustion of Methane

    Directory of Open Access Journals (Sweden)

    Rebeca Pupo

    2011-01-01

    Full Text Available This project calculated the adiabatic flame temperature of a combustion reaction of pure methane and oxygen, assuming that all of the heat liberated by the combustion reaction goes into heating the resulting mixture. Mole fractions of methane to oxygen were computed from 0.05 to 0.95, in increments of 0.05, and then an integral was computed was computed with respect to temperature using the moles of product produced or leftover moles of reactants from the starting mole fraction times the specific heat of each respective gas. The highest adiabatic flame temperature evaluated, occurred at a mole fraction of 0.35.

  9. Flame-Retardant Paper from Wood Fibers Functionalized via Layer-by-Layer Assembly.

    Science.gov (United States)

    Köklükaya, Oruç; Carosio, Federico; Grunlan, Jaime C; Wågberg, Lars

    2015-10-28

    The highly flammable character of cellulose-rich fibers from wood limits their use in some advanced materials. To suppress the flammability and introduce flame-retardant properties to individual pulp fibers, we deposited nanometer thin films consisting of cationic chitosan (CH) and anionic poly(vinylphosphonic acid) (PVPA) on fibers using the layer-by-layer (LbL) technique. The buildup of the multilayer film was investigated in the presence and absence of salt (NaCl) using model cellulose surfaces and a quartz crystal microbalance technique. Fibers were then treated with the same strategy, and the treated fibers were used to prepare paper sheets. A horizontal flame test (HFT) and cone calorimetry were conducted to evaluate the combustion behavior of paper sheets as a function of the number of bilayers deposited on fibers. In HFT, paper made of fibers coated with 20 CH/PVPA bilayers (BL), self-extinguished the flame, while uncoated fibers were completely consumed. Scanning electron microscopy of charred paper after HFT revealed that a thin shell of the charred polymeric multilayer remained after the cellulose fibers had been completely oxidized. Cone calorimetry demonstrated that the phosphorus-containing thin films (20 BL is ∼25 nm) reduced the peak heat release rate by 49%. This study identifies a unique and highly effective way to impart flame-retardant characteristic to pulp fibers and the papers made from these fibers. PMID:26457504

  10. The Cousins of Stuxnet: Duqu, Flame, and Gauss

    Directory of Open Access Journals (Sweden)

    Márk Félegyházi

    2012-11-01

    Full Text Available Stuxnet was the first targeted malware that received worldwide attention forcausing physical damage in an industrial infrastructure seemingly isolated from the onlineworld. Stuxnet was a powerful targeted cyber-attack, and soon other malware samples were discovered that belong to this family. In this paper, we will first present our analysis of Duqu, an information-collecting malware sharing striking similarities with Stuxnet. Wedescribe our contributions in the investigation ranging from the original detection of Duquvia finding the dropper file to the design of a Duqu detector toolkit. We then continue with the analysis of the Flame advanced information-gathering malware. Flame is unique in thesense that it used advanced cryptographic techniques to masquerade as a legitimate proxyfor the Windows Update service. We also present the newest member of the family, called Gauss, whose unique feature is that one of its modules is encrypted such that it can onlybe decrypted on its target system; hence, the research community has not yet been able to analyze this module. For this particular malware, we designed a Gauss detector serviceand we are currently collecting intelligence information to be able to break its very specialencryption mechanism. Besides explaining the operation of these pieces of malware, wealso examine if and how they could have been detected by vigilant system administrators manually or in a semi-automated manner using available tools. Finally, we discuss lessonsthat the community can learn from these incidents. We focus on technical issues, and avoidspeculations on the origin of these threats and other geopolitical questions.

  11. 光质对火焰无核葡萄胚挽救及试管苗生长发育的影响%Effect of light quality on embryo rescue and test-tube plantlets growth and development of Flame Seedless

    Institute of Scientific and Technical Information of China (English)

    李玉玲; 王勇; 郭平峰; 伍国红; 骆强伟

    2015-01-01

    以火焰无核自交胚珠为试材,研究了红光、蓝光、白光及暗处理对胚发育、胚萌发及试管苗生长发育的影响。结果表明:3种光质处理对胚发育均有一定促进作用,但与对照未达到显著性水平。在胚萌发阶段,红光对胚萌发有明显的促进作用。在试管苗发育成苗阶段,以蓝光处理的试管苗最为矮壮,红光下葡萄胚挽救苗试管苗节间最长,发育最高,叶绿素含量最低;各处理试管苗继代后移栽成活率均可达到90%以上。%The open pollination ovules from flame Seedless were used to investigate the effect of diffierent light quality on the proportion of embryo development and germination ,and test-tube plantlets growth and development in vitro, including red light, blue light, white light and dark condition. The results showed that three lights had positive effect on embryo during ovule development, but did not significantly; Red light could promote obsively embryo germination; the plantlets were the most stocky under blue light. Red light was favorable to the longitudinal growth of the test-tube Plantlets, Chlorophyll content were the lowest. Each treatment plantlets transplant survival rate could reach 90%.

  12. A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: Comparison of image quality and diagnostic performance

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hye Shin; Kim, Sun Mi; Jang, Mi Jung; Yun, Bo La; Kim, Boh Young [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Ko, Eun Sook; Han, Boo Kyung [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Choi, Hye Young [Dept. of Radiology, Gyeongsang National University Hospital, Jinju (Korea, Republic of)

    2014-06-15

    To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of {sup M}ammogram enhancement ver. 2.0{sup ;} group B (SMB), specimen mammography with application of {sup M}ammogram enhancement ver. 2.0{sup .} Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

  13. A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: Comparison of image quality and diagnostic performance

    International Nuclear Information System (INIS)

    To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of Mammogram enhancement ver. 2.0; group B (SMB), specimen mammography with application of Mammogram enhancement ver. 2.0. Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

  14. Observation of premixed flame fronts by laser tomography

    Institute of Scientific and Technical Information of China (English)

    Kejin MU; Yue WANG; Yu LEI; Zhedian ZHANG; Chaoqun NIE; Yunhan XIAO

    2008-01-01

    The principle of combustion field detection by using laser tomography, as well as exploitation of the laser tomography apparatus and the tool for image processing is described. An experiment detecting flame fronts by laser tomography was made by employing a V-shaped pre-mixed flame. The results show that the instantaneous geo-metric shape of flame wrinkles within the light sheet can be clearly resolved. The contours of the flame fronts are precisely tracked through active contour models (ACM) from the digital images of laser tomography, laying the basis for the quantitative analysis of flame wrinkling and propagation.

  15. Protein Quality, Growth, and Malnutrition: Advances in Science and the Role of Dairy Ingredients in Food Aid: Introduction.

    Science.gov (United States)

    Whitsett-Morrow, Dacia; LaGrange, Veronique

    2016-03-01

    This article is the introduction to our formal proceedings of the symposium titled "Protein Quality, Growth and Malnutrition: Latest Scientific Findings and the Role of Dairy in Food Aid," held during the Experimental Biology 2015 annual meeting in Boston, Massachusetts.

  16. Quality of life assessment in advanced cancer patients treated at home, an inpatient unit, and a day care center

    OpenAIRE

    Leppert, Wojciech

    2014-01-01

    Wojciech Leppert,1 Mikolaj Majkowicz,2 Maria Forycka,1 Eleonora Mess,3 Agata Zdun-Ryzewska2 1Department of Palliative Medicine, Poznan University of Medical Sciences, Poznan, Poland; 2Department of Quality of Life Research, Gdansk Medical University, Gdansk, Poland; 3Palliative Care Nursing Department, Wroclaw Medical University, Wroclaw, Poland Aim of the study: To assess quality of life (QoL) in cancer patients treated at home, at an in-patient palliative care unit (PCU), and at a day care...

  17. Radical recombinations in acetylene-air flames

    NARCIS (Netherlands)

    Zeegers, P.J.Th.; Alkemade, C.T.J.

    1965-01-01

    In this paper an analysis is given of the behaviour of excess radical concentrations, H, OH and O as a function of height above the reaction zone in premixed acetylene-air flames at 2–200° to 2400°K and 1 atmosphere pressure. The intensity was measured of the Li resonance line which is related to th

  18. Numerical study of one swirling flame

    DEFF Research Database (Denmark)

    Yang, Yang; Kær, Søren Knudsen; Yin, Chungen

    This paper presents numerical study of one of Sydney swirl flames. Good agreements gained between numerical results and the experimental data. Reynolds-averaged Navier-Stokes (RANS) and large eddy simulation (LES) methods show different flow patterns in isothermal and reacting case. The influence...

  19. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

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

    2003-01-01

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

  20. The VLT-FLAMES Tarantula survey

    NARCIS (Netherlands)

    W.D. Taylor; C.J. Evans; V. Henault-Brunet; N. Bastian; Y. Beletsky; J. Bestenlehner; I. Brott; M. Cantiello; G. Carraro; J.S. Clark; P.A. Crowther; A. de Koter; S.E. de Mink; E. Doran; P.L. Dufton; P. Dunstall; M. Gieles; G. Grafener; A. Herrero; I.D. Howarth; N. Langer; D.J. Lennon; J Maiz-Apellaniz; N. Markova; P. Najarro; J. Puls; H.A.A. Sana; S. Simon-Diaz; S.J. Smartt; V.E. Stroud; J.T. van Loon; J.S. Vink; N.R. Walborn

    2011-01-01

    The VLT-FLAMES Tarantula Survey is an ESO Large Programme that has provided multi-epoch spectroscopy of over 1000 stars in the 30 Doradus region in the Large Magellanic Cloud. Armed with this unique dataset the assembled consortium is now addressing a broad range of fundamental questions in both ste

  1. Experiments and modelling on vertical flame spread

    Energy Technology Data Exchange (ETDEWEB)

    Keski-Rahkonen, O.; Mangs, J. [VTT Building and Transport, Espoo (Finland)

    2004-07-01

    he principle and some preliminary results are shown of a new vertical flame spread modelling effort. Quick experimental screenings on relevant phenomena are made, some models are evaluated, and a new set of needed measuring instruments is proposed. Finally a single example of FRNC cable is shown as application of the methods. (orig.)

  2. The VLT-FLAMES Tarantula Survey

    NARCIS (Netherlands)

    Taylor, W.D.; Evans, C.J.; Brott, I.; Cantiello, M.; de Koter, A.; de Mink, S.E.; Langer, N.; Walborn, N.R.

    2010-01-01

    The VLT-FLAMES Tarantula Survey is an ESO Large Programme that has provided multi-epoch spectroscopy of over 1000 stars in the 30 Doradus region in the Large Magellanic Cloud. Armed with this unique dataset the assembled consortium is now addressing a broad range of fundamental questions in both ste

  3. Thermophotovoltaics, wood powder and fuel quality

    Energy Technology Data Exchange (ETDEWEB)

    Marks, J. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Operational Efficiency; Broman, L.; Jarefors, K. [Solar Energy Research Center, Borlaenge (Sweden)

    1998-06-01

    PV cells can be used for electricity production based on other heat sources than the sun. If the temperature of the source is around 1500 K it is possible to get reasonably high conversion efficiency from heat radiation to electricity. This is due to recent advances in low-bandgap PV cells and selectively emitting fibrous emissive burners. There are some different biomass fuels capable of producing this temperature in the flame, especially gas and liquid fuels of different kinds. Wood powder is the only solid wood fuel with a sufficiently stable quality and properties for this high temperature combustion. A joint project between SERC, SLU and National Renewable Energy Laboratory NREL in Golden, Colorado, USA aims at building a wood powder fuelled thermophotovoltaic (TPV) generator for cogeneration of heat and electricity. A stable flame temperature of 1500 K has been achieved in a prototype pilot-scale burner that includes feeder and combustion chamber. Furthermore, a setup for measuring TPV cell efficiency for a wide region of black body emitter temperatures and cell irradiation has been constructed and several 0.6 eV GaInAs TPV cells have been investigated. A setup for testing the chain IR emitter - selectively reflecting filter - TPV cell has been designed. In order to limit the region of filter incident angles, which will make the filter act more efficiently, a special geometry of the internally reflecting tube that transmits the radiation is considered 23 refs, 4 figs

  4. Power-Law Wrinkling Turbulence-Flame Interaction Model for Astrophysical Flames

    CERN Document Server

    Jackson, Aaron P; Calder, Alan C

    2014-01-01

    We extend a model for turbulence-flame interactions (TFI) to consider astrophysical flames with a particular focus on combustion in type Ia supernovae. The inertial range of the turbulent cascade is nearly always under-resolved in simulations of astrophysical flows, requiring the use of a model in order to quantify the effects of subgrid-scale wrinkling of the flame surface. We provide implementation details to extend a well-tested TFI model to low-Prandtl number flames for use in the compressible hydrodynamics code FLASH. A local, instantaneous measure of the turbulent velocity is calibrated for FLASH and verification tests are performed. Particular care is taken to consider the relation between the subgrid rms turbulent velocity and the turbulent flame speed, especially for high-intensity turbulence where the turbulent flame speed is not expected to scale with the turbulent velocity. Finally, we explore the impact of different TFI models in full-star, three-dimensional simulations of type Ia supernovae.

  5. Radiation Heat Transfer in Particle-Laden Gaseous Flame: Flame Acceleration and Triggering Detonation

    CERN Document Server

    Liberman, M A; Kiverin, A D

    2015-01-01

    In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase due to the radiation preheating becomes larger for a flame with lower velocity. For a flame with small enough velocity temperature of the radiation preheating may exceed the crossover temperature, so that the radiation heat transfer may become a dominant mechanism of the flame propagation. In the case of non-uniform distribution of particles, the temperature gradient formed due to the radiation preheating can initiate either deflagration or detonation ahead of the original flame via the Zel'dovich's gradient mechanism. Th...

  6. Laminar Flame Speeds of Gasoline Surrogates Measured with the Flat Flame Method

    KAUST Repository

    Liao, Y.-H.

    2016-01-27

    © 2016 American Chemical Society. The adiabatic, laminar flame speeds of gasoline surrogates at atmospheric pressure over a range of equivalence ratios of = 0.8-1.3 and unburned gas temperatures of 298-400 K are measured with the flat flame method, which produces a one-dimensional flat flame free of stretch. Surrogates used in the current work are the primary reference fuels (PRFs, mixtures of n-heptane and isooctane), the toluene reference fuels (TRFs, mixtures of toluene and PRFs), and the ethanol reference fuels (ERFs, mixtures of ethanol and PRFs). In general, there is good agreement between the present work and the literature data for single-component fuel and PRF mixtures. Surrogates of TRF mixtures are found to exhibit comparable flame speeds to a real gasoline, while there is discrepancy observed between isooctane and gasoline. Moreover, the laminar flame speeds of TRF mixtures with similar fractions of n-heptane are found to be insensitive to the quantity of toluene in the mixture. Mixtures of ERFs exhibit comparable flame speeds to those of TRFs with similar mole fractions of n-heptane and isooctane.

  7. Flame retardancy and its mechanism of polymers flame retarded by DBDPE/Sb2O3

    Institute of Scientific and Technical Information of China (English)

    ZUO Jian-dong; LI Rong-xun; FENG Shao-hua; LIU Guang-ye; ZHAO Jian-qing

    2008-01-01

    The flammability characterization and thermal composition of polymers flame retarded by decabromodiphenylethane(DBDPE) and antimony trioxide (Sb2O3) were studied by cone calorimeter and thermogravimetry (TG). The results show thatABS/DBDPE/Sb2O3 has the similar flammability parameters and thermal composition curves to ABS/DBDPO/Sb3O3. It suggests thatDBDPE/Sb2O3 has the similar flame retardant behavior to DBDPO/Sb2O3. The heat release rate (HRR) and the effect heat combustion (EHC) curves of polymers flame retarded by DBDPE/Sb2O3 all decrease, but the mass loss rate (MLR) curve slightly increase. It shows that the decrease of HRR is not due to the increase of char formation ratio but the generation of incombustible gases. The major flame retardant mechanism of DBDPE/Sb2O3 is gas phase flame retardant mechanism. Increasing content of Sb2O3in DBDPE/Sb2O3 can improve the flame retardant property and thermal stability of aerylonitrile butadiene styrene. Sb203 has a good synergistic effect with DBDPE.

  8. An evaluation of the total quality management implementation strategy for the advanced solid rocket motor project at NASA's Marshall Space Flight Center. M.S. Thesis - Tennessee Univ.

    Science.gov (United States)

    Schramm, Harry F.; Sullivan, Kenneth W.

    1991-01-01

    An evaluation of the NASA's Marshall Space Flight Center (MSFC) strategy to implement Total Quality Management (TQM) in the Advanced Solid Rocket Motor (ASRM) Project is presented. The evaluation of the implementation strategy reflected the Civil Service personnel perspective at the project level. The external and internal environments at MSFC were analyzed for their effects on the ASRM TQM strategy. Organizational forms, cultures, management systems, problem solving techniques, and training were assessed for their influence on the implementation strategy. The influence of ASRM's effort was assessed relative to its impact on mature projects as well as future projects at MSFC.

  9. Effects of advanced treatment of municipal wastewater on the white river near Indianapolis, Indiana: Trends in water quality, 1978-86. Geological Survey water supply paper

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C.G.; Wangsness, D.J.

    1994-01-01

    The report describes changes in the water quality of the White River that occurred after the implementation of Advanced Wastwater Treatment (AWT). The report includes analyses of data collected from three locations on the White River between 1978 and 1986 by the City of Indianapolis, Department of Public Works, and by the USGS and data from one location on the White River collected by the Indiana State Board of Health between 1958 and 1986. The report also includes analyses of daily effluent data from the Belmont and Southport municipal wastewater-treatment plants from 1978 through 1986.

  10. Modeling and simulation of axisymmetric stagnation flames

    Science.gov (United States)

    Sone, Kazuo

    Laminar flame modeling is an important element in turbulent combustion research. The accuracy of a turbulent combustion model is highly dependent upon our understanding of laminar flames and their behavior in many situations. How much we understand combustion can only be measured by how well the model describes and predicts combustion phenomena. One of the most commonly used methane combustion models is GRI-Mech 3.0. However, how well the model describes the reacting flow phenomena is still uncertain even after many attempts to validate the model or quantify uncertainties. In the present study, the behavior of laminar flames under different aerodynamic and thermodynamic conditions is studied numerically in a stagnation-flow configuration. In order to make such a numerical study possible, the spectral element method is reformulated to accommodate the large density variations in methane reacting flows. In addition, a new axisymmetric basis function set for the spectral element method that satisfies the correct behavior near the axis is developed, and efficient integration techniques are developed to accurately model axisymmetric reacting flow within a reasonable amount of computational time. The numerical method is implemented using an object-oriented programming technique, and the resulting computer program is verified with several different verification methods. The present study then shows variances with the commonly used GRI-Mech 3.0 chemical kinetics model through a direct simulation of laboratory flames that allows direct comparison to experimental data. It is shown that the methane combustion model based on GRI-Mech 3.0 works well for methane-air mixtures near stoichiometry. However, GRI-Mech 3.0 leads to an overprediction of laminar flame speed for lean mixtures and an underprediction for rich mixtures. This result is slightly different from conclusion drawn in previous work, in which experimental data are compared with a one-dimensional numerical solutions

  11. Leading-Edge Velocities and Lifted Methane Jet Flame Stability

    Directory of Open Access Journals (Sweden)

    W. Wang

    2010-01-01

    Full Text Available Current interest exists in understanding reaction-zone dynamics and mechanisms with respect to how they counterpropagate against incoming reactants. Images of flame position and flow-field morphology are presented from flame chemiluminescence and particle image velocimetry (PIV measurements. In the present study, PIV experiments were carried out to measure the methane jet lifted-flame flow-field velocities in the vicinity of the flame leading edge. Specifically, velocity fields within the high-temperature zone were examined in detail, which complements previous studies, whose prime focus is the flow-field upstream of the high-temperature boundary. PIV data is used not only to determine the velocities, but, along with chemiluminescence images, to also indicate the approximate location of the reaction zone (further supported by/through the leading-edge flame velocity distributions. The velocity results indirectly support the concept that the flame is anchored primarily through the mechanism of partially premixed flame propagation.

  12. 3D velocity measurements in a premixed flame by tomographic PIV

    Science.gov (United States)

    Tokarev, M. P.; Sharaborin, D. K.; Lobasov, A. S.; Chikishev, L. M.; Dulin, V. M.; Markovich, D. M.

    2015-06-01

    Tomographic particle image velocimetry (PIV) has become a standard tool for 3D velocity measurements in non-reacting flows. However, the majority of the measurements in flows with combustion are limited to small resolved depth compared to the size of the field of view (typically 1 : 10). The limitations are associated with inhomogeneity of the volume illumination and the non-uniform flow seeding, the optical distortions and errors in the 3D calibration, and the unwanted flame luminosity. In the present work, the above constraints were overcome for the tomographic PIV experiment in a laminar axisymmetric premixed flame. The measurements were conducted for a 1 : 1 depth-to-size ratio using a system of eight CCD cameras and a 200 mJ pulsed laser. The results show that camera calibration based on the triangulation of the tracer particles in the non-reacting conditions provided reliable accuracy for the 3D image reconstruction in the flame. The modification of the tomographic reconstruction allowed a posteriori removal of unwanted bright objects, which were located outside of the region of interest but affected the reconstruction quality. This study reports on a novel experience for the instantaneous 3D velocimetry in laboratory-scale flames by using tomographic PIV.

  13. [Determination of potassium in sodium by flame atomic emission spectroscopy].

    Science.gov (United States)

    Xie, C; Wen, X; Jia, Y; Sun, S

    2001-06-01

    Sodium is used as a coolant in China experiment fast reactor (CEFR). Potassium in sodium has an influence on heat property of reactor. A analytical method has been developed to determinate potassium in sodium by flame atomic emission spectroscopy. Sodium sample is dissolved by ultrasonic humidifier. The working conditions of the instrument and inTerferences from matrix sodium, acid effect and concomitant elements have been studied. Standard addition experiments are carried out with potassium chloride. The percentage recoveries are 94.7%-109.8%. The relative standard deviation is 4.2%. The analytical range accords with sodium quality control standard of CFFR. The precision corresponds to the international analytical method in sodium coolant reactor. PMID:12947670

  14. Flame Propagation of Butanol Isomers/Air Mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Veloo, Peter S.; Egolfopoulos, Fokion N.

    2011-01-01

    An experimental and computational study was conducted on the propagation of flames of saturated butanol isomers. The experiments were performed in the counterflow configuration under atmospheric pressure, unburned mixture temperature of 343 K, and for a wide range of equivalence ratios. The experiments were simulated using a recent kinetic model for the four isomers of butanol. Results indicate that n-butanol/air flames propagate somewhat faster than both sec-butanol/air and iso-butanol/air flames, and that tert-butanol/air flames propagate notably slower compared to the other three isomers. Reaction path analysis of tert-butanol/air flames revealed that iso-butene is a major intermediate, which subsequently reacts to form the resonantly stable iso-butenyl radical retarding thus the overall reactivity of tert-butanol/air flames relatively to the other three isomers. Through sensitivity analysis, it was determined that the mass burning rates of sec-butanol/air and iso-butanol/air flames are sensitive largely to hydrogen, carbon monoxide, and C{sub 1}–C{sub 2} hydrocarbon kinetics and not to fuel-specific reactions similarly to n-butanol/air flames. However, for tert-butanol/air flames notable sensitivity to fuel-specific reactions exists. While the numerical results predicted closely the experimental data for n-butanol/air and sec-butanol/air flames, they overpredicted and underpredicted the laminar flame speeds for iso-butanol/air and tert-butanol/air flames respectively. It was demonstrated further that the underprediction of the laminar flame speeds of tert-butanol/air flames by the model was most likely due to deficiencies of the C{sub 4}-alkene kinetics.

  15. Relationship between quality of life and clinical outcomes in advanced non-small cell lung cancer: best supportive care (BSC) versus BSC plus chemotherapy.

    Science.gov (United States)

    Thongprasert, S; Sanguanmitra, P; Juthapan, W; Clinch, J

    1999-04-01

    In a prospective randomized study, 287 patients with advanced non-small cell lung cancer (NSCLC) stage IIIb or IV with ECOG performance status (PS) 0-1 or 2 were randomly assigned to receive either best supportive care (BSC) or supportive care plus combination chemotherapy (IEP regimen: ifosfamide 3 gm/m2 IV with mesna uroprotection, epirubicin 60 mg/m2 IV on day 1 and cisplatin 60 mg/m2 IV on day 2; or MVP regimen: mitomycin-C 8 mg/m2, cisplatin 100 mg/m2 IV on day 1, vinblastine 4 mg/m2 IV on days 1 and 15). Serial assessment of Karnofsky performance status (KPS), modified Functional Living Index-Cancer (T-FLIC) and modified Quality of Life-Index (T-QLI) were used to estimate the quality of life. Interviews were done at entry, at the third month and at 2 months post complete treatment. At least two courses of chemotherapy were considered to be adequate for response evaluation. Patients were treated for a total of four to six courses or until progression of disease. Partial response rates were 40 and 41.7% in IEP and MVP arms. Median survival durations were 5.9 and 8.1 months for the IEP and MVP chemotherapy arms, and 4.1 months for BSC (log-rank test: P = 0.0003). One year survival was 13, 29.8 and 39.3% for the BSC, IEP and MVP regimens, respectively. Two years survival was 7.8, 6.4 and 13.1% for the BSC, IEP and MVP regimens, respectively. Improvement in quality of life (QOL) scores at the first, second and third interview were seen in chemotherapy arms only, not in the BSC arm. We conclude that combination chemotherapy improves the quality of life as well as prolonging the survival of patients with advanced NSCLC.

  16. Behaviors of tribrachial edge flames and their interactions in a triple-port burner

    KAUST Repository

    Yamamoto, Kazuhiro

    2015-05-01

    In a triple-port burner, various non-premixed flames have been observed previously. Especially for the case with two lifted flames, such configuration could be suitable in studying interaction between two tribrachial flames. In the present study, the flame characteristics have been investigated numerically by adopting a reduced kinetic mechanism in the triple-port burner. Four different types of flame configurations, including two attached flames, inner lifted/outer attached flames, inner attached/outer lifted flames, and twin lifted flames, were successfully simulated depending on the flow conditions. The representative edge propagation speed of a single lifted flame or an upstream lifted flame in the case of twin lifted flames increased as the liftoff height became higher. In the twin lifted flames, the inner lifted flame was affected appreciably when the other flame was located further upstream such that the lifted flame located further downstream encountered the axial velocity acceleration induced by the gas expansion from the lifted flame located upstream, while thermal effects were not observed since the temperature of the incoming flow toward the lifted flame was not affected. A unique flip-flop behavior between the inner and outer flames, observed experimentally previously, was successfully captured in the simulation such that the inner lifted flame became attached to the nozzle as the liftoff height of the outer lifted flame grew higher with an increase in the outer air velocity.

  17. Third-generation dual-source 70-kVp chest CT angiography with advanced iterative reconstruction in young children: image quality and radiation dose reduction

    Energy Technology Data Exchange (ETDEWEB)

    Rompel, Oliver; Janka, Rolf; Lell, Michael M.; Uder, Michael; Hammon, Matthias [University Hospital Erlangen, Department of Radiology, Erlangen (Germany); Gloeckler, Martin; Dittrich, Sven [University Hospital Erlangen, Department of Pediatric Cardiology, Erlangen (Germany); Cesnjevar, Robert [University Hospital Erlangen, Department of Pediatric Cardiac Surgery, Erlangen (Germany)

    2016-04-15

    Many technical updates have been made in multi-detector CT. To evaluate image quality and radiation dose of high-pitch second- and third-generation dual-source chest CT angiography and to assess the effects of different levels of advanced modeled iterative reconstruction (ADMIRE) in newborns and children. Chest CT angiography (70 kVp) was performed in 42 children (age 158 ± 267 days, range 1-1,194 days). We evaluated subjective and objective image quality, and radiation dose with filtered back projection (FBP) and different strength levels of ADMIRE. For comparison were 42 matched controls examined with a second-generation 128-slice dual-source CT-scanner (80 kVp). ADMIRE demonstrated improved objective and subjective image quality (P <.01). Mean signal/noise, contrast/noise and subjective image quality were 11.9, 10.0 and 1.9, respectively, for the 80 kVp mode and 11.2, 10.0 and 1.9 for the 70 kVp mode. With ADMIRE, the corresponding values for the 70 kVp mode were 13.7, 12.1 and 1.4 at strength level 2 and 17.6, 15.6 and 1.2 at strength level 4. Mean CTDI{sub vol}, DLP and effective dose were significantly lower with the 70-kVp mode (0.31 mGy, 5.33 mGy*cm, 0.36 mSv) compared to the 80-kVp mode (0.46 mGy, 9.17 mGy*cm, 0.62 mSv; P <.01). The third-generation dual-source CT at 70 kVp provided good objective and subjective image quality at lower radiation exposure. ADMIRE improved objective and subjective image quality. (orig.)

  18. Third-generation dual-source 70-kVp chest CT angiography with advanced iterative reconstruction in young children: image quality and radiation dose reduction

    International Nuclear Information System (INIS)

    Many technical updates have been made in multi-detector CT. To evaluate image quality and radiation dose of high-pitch second- and third-generation dual-source chest CT angiography and to assess the effects of different levels of advanced modeled iterative reconstruction (ADMIRE) in newborns and children. Chest CT angiography (70 kVp) was performed in 42 children (age 158 ± 267 days, range 1-1,194 days). We evaluated subjective and objective image quality, and radiation dose with filtered back projection (FBP) and different strength levels of ADMIRE. For comparison were 42 matched controls examined with a second-generation 128-slice dual-source CT-scanner (80 kVp). ADMIRE demonstrated improved objective and subjective image quality (P <.01). Mean signal/noise, contrast/noise and subjective image quality were 11.9, 10.0 and 1.9, respectively, for the 80 kVp mode and 11.2, 10.0 and 1.9 for the 70 kVp mode. With ADMIRE, the corresponding values for the 70 kVp mode were 13.7, 12.1 and 1.4 at strength level 2 and 17.6, 15.6 and 1.2 at strength level 4. Mean CTDIvol, DLP and effective dose were significantly lower with the 70-kVp mode (0.31 mGy, 5.33 mGy*cm, 0.36 mSv) compared to the 80-kVp mode (0.46 mGy, 9.17 mGy*cm, 0.62 mSv; P <.01). The third-generation dual-source CT at 70 kVp provided good objective and subjective image quality at lower radiation exposure. ADMIRE improved objective and subjective image quality. (orig.)

  19. Investigation of Alien Wavelength Quality in Live Multi-Domain, Multi-Vendor Link Using Advanced Simulation Tool

    DEFF Research Database (Denmark)

    Petersen, Martin Nordal; Nuijts, Roeland; Bjorn, Lars Lange

    2014-01-01

    This article presents an advanced optical model for simulation of alien wavelengths in multi-domain and multi-vendor dense wavelength-division multiplexing networks. The model aids optical network planners with a better understanding of the non-linear effects present in dense wavelength-division ......This article presents an advanced optical model for simulation of alien wavelengths in multi-domain and multi-vendor dense wavelength-division multiplexing networks. The model aids optical network planners with a better understanding of the non-linear effects present in dense wavelength......-division multiplexing systems and better utilization of alien wavelengths in future applications. The limiting physical effects for alien wavelengths are investigated in relation to power levels, channel spacing, and other factors. The simulation results are verified through experimental setup in live multi...

  20. QA [Quality Assurance] role in advanced energy activities: Towards an /open quotes/orthodox/close quotes/ Quality Program: Canonizing the traditions at Fermilab

    International Nuclear Information System (INIS)

    After a brief description of the goal of Fermi National Accelerator Laboratory (Fermilab) this paper poses and answers three questions related to Quality Assurance (QA) at the Laboratory. First, what is the difference between 'orthodox' and 'unorthodox' QA and is there a place for 'orthodox' QA at a laboratory like Fermilab? Second, are the deeper philosophical and cultural frameworks of high-energy physics acommodating or antagonistic to an 'orthodox' QA Program? Finally, faced with the task of developing an institutional QA program for Fermilab where does one begin? The paper is based on experience with the on-going development and implementation of an institutional QA Program at Fermilab. 10 refs

  1. Investigation of quality of life in the treatment of locally advanced and recurrent oropharyngeal cancer: State-of the-art

    Directory of Open Access Journals (Sweden)

    D. V. Sikorsky

    2015-01-01

    Full Text Available Postsurgical survival is considered to be indicators of treatment efficiency in most cases. However, the sociomedical rehabilitation of patients in this group is no less important; not only life expectancy, but also functional rehabilitation and quality of life are in the lead in patients with Stage III–IVA due to their low 2-year and much lower 5-year survival. The main efficiency criterion is patients, quality of life as compared to antitumor treatment programs in the absence of differences in survival.As the only chance of cure or life prolongation in most cases, multicomponent surgery for locally advanced and recurrent oropharyngeal cancer may be refused by a patient for fear of being lost to society. Identification of surgical treatment-induced changes in quality of life in patients may be used as a criterion for assessing the performed operations.The body's changes in a patient with otopharyngeal cancer are associated with impairment of basic physiological functions (deglutition, mastication, and breathing, sensitivity (taste, olfaction, and hearing, and individual characteristics of a human being (for example, appearance and voice. The quality of life is integral characteristics of the physical, psychological, emotional, and social functioning of a patient, which is based on his subjective perception. The methods for studying the quality of life include first of all questionnaires that are classified as general and special ones.The general questionnaires are intended to assess the quality of life of both healthy individuals and patients regardless of their disease; the special questionnaires are used to study that in certain categories and groups of patients. The general questionnaires allow the comparison of patients with a population of healthy people. Account must be also taken of the fact that the quality of life varies with age and comorbidities. A great deal of procedures for measuring the quality of life in different groups of

  2. Numerical Study of Buoyancy and Differential Diffusion Effects on the Structure and Dynamics of Triple Flames

    Science.gov (United States)

    Chen, J. -Y.; Echekki, T.

    1999-01-01

    Triple flames arise in a number of practical configurations where fuel and oxidizer are partially premixed, such as in the base of a lifted jet flame. Past experimental studies, theoretical analyses, and numerical modeling of triple flames suggested the potential role of triple flames in stabilizing turbulent flames and in promoting flame propagation. From recent numerical simulations of laminar triple flames, a strong influence of differential diffusion among species and heat on the triple flame structure has been gradually appreciated. This paper reports preliminary numerical results on the influence of gravity and differential diffusion effects on the structure and dynamics of triple flames with a one-step global irreversible chemistry model.

  3. Nurse Mentors to Advance Quality Improvement in Primary Health Centers: Lessons From a Pilot Program in Northern Karnataka, India.

    Science.gov (United States)

    Fischer, Elizabeth A; Jayana, Krishnamurthy; Cunningham, Troy; Washington, Maryann; Mony, Prem; Bradley, Janet; Moses, Stephen

    2015-12-01

    High-quality care during labor, delivery, and the postpartum period is critically important since maternal and child morbidity and mortality are linked to complications that arise during these stages. A nurse mentoring program was implemented in northern Karnataka, India, to improve quality of services at primary health centers (PHCs), the lowest level in the public health system that offers basic obstetric care. The intervention, conducted between August 2012 and July 2014, employed 53 full-time nurse mentors and was scaled-up in 385 PHCs in 8 poor rural districts. Each mentor was responsible for 6 to 8 PHCs and conducted roughly 6 mentoring visits per PHC in the first year. This paper reports the results of a qualitative inquiry, conducted between September 2012 and April 2014, assessing the program's successes and challenges from the perspective of mentors and PHC teams. Data were gathered through 13 observations, 9 focus group discussions with mentors, and 25 individual and group interviews with PHC nurses, medical officers, and district health officers. Mentors and PHC staff and leaders reported a number of successes, including development of rapport and trust between mentors and PHC staff, introduction of team-based quality improvement processes, correct and consistent use of a new case sheet to ensure adherence to clinical guidelines, and increases in staff nurses' knowledge and skills. Overall, nurses in many PHCs reported an increased ability to provide care according to guidelines and to handle maternal and newborn complications, along with improvements in equipment and supplies and referral management. Challenges included high service delivery volumes and/or understaffing at some PHCs, unsupportive or absent PHC leadership, and cultural practices that impacted quality. Comprehensive mentoring can build competence and improve performance by combining on-the-job clinical and technical support, applying quality improvement principles, and promoting team

  4. Nurse Mentors to Advance Quality Improvement in Primary Health Centers: Lessons From a Pilot Program in Northern Karnataka, India.

    Science.gov (United States)

    Fischer, Elizabeth A; Jayana, Krishnamurthy; Cunningham, Troy; Washington, Maryann; Mony, Prem; Bradley, Janet; Moses, Stephen

    2015-12-01

    High-quality care during labor, delivery, and the postpartum period is critically important since maternal and child morbidity and mortality are linked to complications that arise during these stages. A nurse mentoring program was implemented in northern Karnataka, India, to improve quality of services at primary health centers (PHCs), the lowest level in the public health system that offers basic obstetric care. The intervention, conducted between August 2012 and July 2014, employed 53 full-time nurse mentors and was scaled-up in 385 PHCs in 8 poor rural districts. Each mentor was responsible for 6 to 8 PHCs and conducted roughly 6 mentoring visits per PHC in the first year. This paper reports the results of a qualitative inquiry, conducted between September 2012 and April 2014, assessing the program's successes and challenges from the perspective of mentors and PHC teams. Data were gathered through 13 observations, 9 focus group discussions with mentors, and 25 individual and group interviews with PHC nurses, medical officers, and district health officers. Mentors and PHC staff and leaders reported a number of successes, including development of rapport and trust between mentors and PHC staff, introduction of team-based quality improvement processes, correct and consistent use of a new case sheet to ensure adherence to clinical guidelines, and increases in staff nurses' knowledge and skills. Overall, nurses in many PHCs reported an increased ability to provide care according to guidelines and to handle maternal and newborn complications, along with improvements in equipment and supplies and referral management. Challenges included high service delivery volumes and/or understaffing at some PHCs, unsupportive or absent PHC leadership, and cultural practices that impacted quality. Comprehensive mentoring can build competence and improve performance by combining on-the-job clinical and technical support, applying quality improvement principles, and promoting team

  5. The association of quality of life with potentially remediable disruptions of circadian sleep/activity rhythms in patients with advanced lung cancer

    Directory of Open Access Journals (Sweden)

    Braun Donald P

    2011-05-01

    Full Text Available Abstract Background Cancer patients routinely develop symptoms consistent with profound circadian disruption, which causes circadian disruption diminished quality of life. This study was initiated to determine the relationship between the severity of potentially remediable cancer-associated circadian disruption and quality of life among patients with advanced lung cancer. Methods We concurrently investigated the relationship between the circadian rhythms of 84 advanced lung cancer patients and their quality of life outcomes as measured by the EORTC QLQ C30 and Ferrans and Powers QLI. The robustness and stability of activity/sleep circadian daily rhythms were measured by actigraphy. Fifty three of the patients in the study were starting their definitive therapy following diagnosis and thirty one patients were beginning second-line therapy. Among the patients who failed prior therapy, the median time between completing definitive therapy and baseline actigraphy was 4.3 months, (interquartile range 2.1 to 9.8 months. Results We found that circadian disruption is universal and severe among these patients compared to non-cancer-bearing individuals. We found that each of these patient's EORTC QLQ C30 domain scores revealed a compromised capacity to perform the routine activities of daily life. The severity of several, but not all, EORTC QLQ C30 symptom items correlate strongly with the degree of individual circadian disruption. In addition, the scores of all four Ferrans/Powers QLI domains correlate strongly with the degree of circadian disruption. Although Ferrans/Powers QLI domain scores show that cancer and its treatment spared these patients' emotional and psychological health, the QLI Health/Function domain score revealed high levels of patients' dissatisfaction with their health which is much worse when circadian disruption is severe. Circadian disruption selectively affects specific Quality of Life domains, such as the Ferrans/Powers Health

  6. Turbulent premixed flames on fractal-grid-generated turbulence

    International Nuclear Information System (INIS)

    A space-filling, low blockage fractal grid is used as a novel turbulence generator in a premixed turbulent flame stabilized by a rod. The study compares the flame behaviour with a fractal grid to the behaviour when a standard square mesh grid with the same effective mesh size and solidity as the fractal grid is used. The isothermal gas flow turbulence characteristics, including mean flow velocity and rms of velocity fluctuations and Taylor length, were evaluated from hot-wire measurements. The behaviour of the flames was assessed with direct chemiluminescence emission from the flame and high-speed OH-laser-induced fluorescence. The characteristics of the two flames are considered in terms of turbulent flame thickness, local flame curvature and turbulent flame speed. It is found that, for the same flow rate and stoichiometry and at the same distance downstream of the location of the grid, fractal-grid-generated turbulence leads to a more turbulent flame with enhanced burning rate and increased flame surface area. (paper)

  7. Radiative Extinction of Gaseous Spherical Diffusion Flames in Microgravity

    Science.gov (United States)

    Santa, K. J.; Chao, B. H.; Sunderland, P. B.; Urban, D. L.; Stocker, D. P.; Axelbaum, R. L.

    2007-01-01

    Radiative extinction of spherical diffusion flames was investigated experimentally and numerically. The experiments involved microgravity spherical diffusion flames burning ethylene and propane at 0.98 bar. Both normal (fuel flowing into oxidizer) and inverse (oxidizer flowing into fuel) flames were studied, with nitrogen supplied to either the fuel or the oxygen. Flame conditions were chosen to ensure that the flames extinguished within the 2.2 s of available test time; thus extinction occurred during unsteady flame conditions. Diagnostics included color video and thin-filament pyrometry. The computations, which simulated flow from a porous sphere into a quiescent environment, included detailed chemistry, transport and radiation, and yielded transient results. Radiative extinction was observed experimentally and simulated numerically. Extinction time, peak temperature, and radiative loss fraction were found to be independent of flow rate except at very low flow rates. Radiative heat loss was dominated by the combustion products downstream of the flame and was found to scale with flame surface area, not volume. For large transient flames the heat release rate also scaled with surface area and thus the radiative loss fraction was largely independent of flow rate. Peak temperatures at extinction onset were about 1100 K, which is significantly lower than for kinetic extinction. One observation of this work is that while radiative heat losses can drive transient extinction, this is not because radiative losses are increasing with time (flame size) but rather because the heat release rate is falling off as the temperature drops.

  8. Turbulent premixed flames on fractal-grid-generated turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Soulopoulos, N; Kerl, J; Sponfeldner, T; Beyrau, F; Hardalupas, Y; Taylor, A M K P [Mechanical Engineering Department, Imperial College London, London SW7 2AZ (United Kingdom); Vassilicos, J C, E-mail: ns6@ic.ac.uk [Department of Aeronautics, Imperial College London, London SW7 2AZ (United Kingdom)

    2013-12-15

    A space-filling, low blockage fractal grid is used as a novel turbulence generator in a premixed turbulent flame stabilized by a rod. The study compares the flame behaviour with a fractal grid to the behaviour when a standard square mesh grid with the same effective mesh size and solidity as the fractal grid is used. The isothermal gas flow turbulence characteristics, including mean flow velocity and rms of velocity fluctuations and Taylor length, were evaluated from hot-wire measurements. The behaviour of the flames was assessed with direct chemiluminescence emission from the flame and high-speed OH-laser-induced fluorescence. The characteristics of the two flames are considered in terms of turbulent flame thickness, local flame curvature and turbulent flame speed. It is found that, for the same flow rate and stoichiometry and at the same distance downstream of the location of the grid, fractal-grid-generated turbulence leads to a more turbulent flame with enhanced burning rate and increased flame surface area. (paper)

  9. Early structure of LPG partially premixed conically stabilized flames

    KAUST Repository

    Elbaz, Ayman M.

    2013-01-01

    This paper presents experimental investigation of LPG partially premixed turbulent flames stabilized within a conical nozzle burner under constant degree of partial premixing. The stability limits and mean flame structure are presented based on the mean gas temperature and the concentration of CO, O 2, NO, and HC at the flame early region of reaction. The investigation covered the influence of the nozzle cone angle, the jet exit velocity and the jet equivalence ratio. The stability results show that the flames with cone are more stable than those without cone. For conical stabilized flames, the stability results exhibit three different sensitivity regions between the jet velocity and equivalence ratio. The inflame measurements prove that the flame stability could be attributed to the triple flame structure at the flame leading edge. The data show that the triple flame structure is influenced by cone angle, the jet velocity and the equivalence ratio. The flame is believed to be controlled by the recirculation flow inside the cone. Increasing the cone angle induced higher air entrainment to the reaction zone as depicted by a higher O 2 concentration within the flame leading edge. Increasing the jet velocity to a certain limit enhances the intensity of combustion at the flame leading edge, while excessive increase in jet velocity reduces this intensity. At a fixed jet velocity the higher the equivalence ratio, the higher the amount of fuel diffused and engulfed to the reaction zone, the more delay of the combustion completion and the higher the emission concentrations of the flame. © 2012 Elsevier Inc.

  10. QA (Quality Assurance) role in advanced energy activities: Towards an /open quotes/orthodox/close quotes/ Quality Program: Canonizing the traditions at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Bodnarczuk, M.W.

    1988-02-01

    After a brief description of the goal of Fermi National Accelerator Laboratory (Fermilab) this paper poses and answers three questions related to Quality Assurance (QA) at the Laboratory. First, what is the difference between 'orthodox' and 'unorthodox' QA and is there a place for 'orthodox' QA at a laboratory like Fermilab. Second, are the deeper philosophical and cultural frameworks of high-energy physics acommodating or antagonistic to an 'orthodox' QA Program. Finally, faced with the task of developing an institutional QA program for Fermilab where does one begin. The paper is based on experience with the on-going development and implementation of an institutional QA Program at Fermilab. 10 refs.

  11. Lean premixed flames for low NO{sub x} combustors

    Energy Technology Data Exchange (ETDEWEB)

    Sojka, P.; Tseng, L.; Bryjak, J. [Purdue Univ., West Lafayette, IN (United States)] [and others

    1995-10-01

    Gas turbines are being used throughout the world to generate electricity. Due to increasing fuel costs and environmental concerns, gas turbines must meet stringent performance requirements, demonstrating high thermal efficiencies and low pollutant emissions. In order for U.S. manufactured gas turbines to stay competitive, their NO{sub x} levels must be below 10 ppm and their thermal efficiencies should approach 60%. Current technology is being stretched to achieve these goals. The twin goals of high efficiency and low NO{sub x} emissions require extending the operating range of current gas turbines. Higher efficiency requires operation at higher pressures and temperatures. Lower NO{sub x} emissions requires lower flame temperatures. Lower flame temperatures can be achieved through partially to fully pre-mixed combustion. However, increased performance and lower emissions result in a set of competing goals. In order to achieve a successful compromise between high efficiency and low NO{sub x} emissions, advanced design tools must be developed. One key design tool is a computationally efficient, high pressure, turbulent flow, combustion model capable of predicting pollutant formation in an actual gas turbine. Its development is the goal of this program. Achieving this goal requires completion of three tasks. The first task is to develop a reduced chemical kinetics model describing N{sub O}x formation in natural gas-air systems. The second task is to develop a computationally efficient model that describes turbulence-chemistry interactions. The third task is to incorporate the reduced chemical kinetics and turbulence-chemistry interaction models into a commercially available flow solver and compare its predictions with experimental data obtained under carefully controlled conditions so that the accuracy of model predictions can be evaluated.

  12. Application of simultaneous determination of inorganic ionic species by advanced ion chromatography for water quality monitoring of river water and wastewater

    Institute of Scientific and Technical Information of China (English)

    Nobutake NAKATANI; Daisuke KOZAKI; Kazuhiko TANAKA

    2012-01-01

    In this study,our recent work on advanced ion chromatographic methods for the simultaneous determination of inorganic ionic species such as common anions ( SO42 -,Cl- and NO3- ) and cations (Na+,NH4+,K+,Mg2+,and Ca2 + ),nutrients ( phosphate and silicate) and hydrogen ion/alkalinity are summarized first.Then,the applications using these methods for monitoring environmental water quality are also presented.For the determination of common anions and cations with nutrients,the separation was successfully performed by a polymethacrylate-based weakly acidic cation-exchange column of TSKgel Super IC-A/C ( Tosoh,150 mm x 6.0 mm i.d.) and a mixture solution of 100 mmol/L ascorbic acid and 4 mmol/L 18-crown-6 as acidic eluent with dual detection of conductivity and spectrophotometry.For the determination of hydrogen ion/alkelinity,the separation was conducted by TSKgel ODS-100Z column (Tosoh,150 mm ×4.5 mm i.d.) modified with lithium dodecylsulfate and an eluent of 40 mmol/L LiCl/0.1 mmol/L lithium dodecylsulfate/0.05 mmol/L H2SO4 with conductivity detector.The differences of ion concentration between untreated and treated wastewater showed the variation of ionic species during biological treatment process in a sewage treatment plant.Occurrence and distribution of water-quality conditions were related to the bioavailability and human activity in watershed.From these results,our advanced ion chromatographic methods have contributed significantly for water quality monitoring of environmental waters.

  13. Prospective clinical study on long-term swallowing function and voice quality in advanced head and neck cancer patients treated with concurrent chemoradiotherapy and preventive swallowing exercises.

    Science.gov (United States)

    Kraaijenga, Sophie A C; van der Molen, Lisette; Jacobi, Irene; Hamming-Vrieze, Olga; Hilgers, Frans J M; van den Brekel, Michiel W M

    2015-11-01

    Concurrent chemoradiotherapy (CCRT) for advanced head and neck cancer (HNC) is associated with substantial early and late side effects, most notably regarding swallowing function, but also regarding voice quality and quality of life (QoL). Despite increased awareness/knowledge on acute dysphagia in HNC survivors, long-term (i.e., beyond 5 years) prospectively collected data on objective and subjective treatment-induced functional outcomes (and their impact on QoL) still are scarce. The objective of this study was the assessment of long-term CCRT-induced results on swallowing function and voice quality in advanced HNC patients. The study was conducted as a randomized controlled trial on preventive swallowing rehabilitation (2006-2008) in a tertiary comprehensive HNC center with twenty-two disease-free and evaluable HNC patients as participants. Multidimensional assessment of functional sequels was performed with videofluoroscopy, mouth opening measurements, Functional Oral Intake Scale, acoustic voice parameters, and (study specific, SWAL-QoL, and VHI) questionnaires. Outcome measures at 6 years post-treatment were compared with results at baseline and at 2 years post-treatment. At a mean follow-up of 6.1 years most initial tumor-, and treatment-related problems remained similarly low to those observed after 2 years follow-up, except increased xerostomia (68%) and increased (mild) pain (32%). Acoustic voice analysis showed less voicedness, increased fundamental frequency, and more vocal effort for the tumors located below the hyoid bone (n = 12), without recovery to baseline values. Patients' subjective vocal function (VHI score) was good. Functional swallowing and voice problems at 6 years post-treatment are minimal in this patient cohort, originating from preventive and continued post-treatment rehabilitation programs.

  14. Two-dimensional flame temperature and emissivity measurements of pulverized oxy-coal flames

    International Nuclear Information System (INIS)

    Highlights: ► Two emissivity models were investigated for use with pyrometry in coal flames. ► The oxy-fired coal produced flame temperatures in excess of 2400 K. ► The H. B. Model produced an average temperature 9% lower and emissivity 81% lower. ► Addition of CO2 to the secondary air decreased the flame temperature by over 200 K. ► The measured and calculated decrease in flame temperature with CO2 addition were similar. -- Abstract: A broadband, RGB, two-color pyrometry technique for measuring the flame temperature and total emissivity of a two-dimensional image of a coal flame has been developed and used on an oxy-coal flame. The method uses a single, relatively inexpensive, RGB, digital camera. The camera software permits the light intensities of the red, green, and blue light collected for each pixel to be recorded separately. The response of each pixel was calibrated for each color using a blackbody radiating cavity and a monochrometer, which enabled an absolute, broadband emission measurement. The image obtained by the camera was processed to produce a temperature and total emissivity for each pixel. Two spectral emissivity models were explored for use in determining the temperature and emissivity: a Gray model and Hottel and Broughton’s soot emissivity model. Significant differences of 7.1% in average temperature and 24.2% in average emissivity were found. While neither model is ideal for the entire coal flame, the Hottel and Broughton model was selected for future image processing because the images and analysis suggested soot was the more dominant emitter for most of the image. Images were obtained in a 150 kWth, pulverized-coal reactor at two different mixture oxidizer ratios of O2/CO2. The addition of CO2 decreased the average flame temperature from 2183 K to 2022 K and reduced the average emissivity from 0.59 to 0.13. The increase in CO2 lowered the temperature by increasing the dilution. The increased flow rate caused increased mixing

  15. Numerical study of laminar nonpremixed methane flames in coflow jets: Autoignited lifted flames with tribrachial edges and MILD combustion at elevated temperatures

    KAUST Repository

    M. Al-Noman, Saeed

    2016-07-07

    Autoignition characteristics of laminar nonpremixed methane jet flames in high-temperature coflow air are studied numerically. Several flame configurations are investigated by varying the initial temperature and fuel mole fraction. At a relatively low initial temperature, a non-autoignited nozzle-attached flame is simulated at relatively low jet velocity. When the initial temperature is higher than that required for autoignition, two regimes are investigated: an autoignited lifted flame with tribrachial edge structure and an autoignited lifted flame with Mild combustion. The autoignited lifted flame with tribrachial edge exhibited three branches: lean and rich premixed flame wings and a trailing diffusion flame. Characteristics of kinetic structure for autoignited lifted flames are discussed based on the kinetic structures of homogeneous autoignition and flame propagation of stoichiometric mixture. Results showed that a transition from autoignition to flame propagation modes occurs for reasonably stoichiometric mixtures. The autoignited lifted flame with Mild combustion occurs when methane fuel is highly diluted with nitrogen. The kinetic structure analysis shows that the characteristics of Mild combustion can be treated as an autoignited lean premixed lifted flame. Transition behavior from Mild combustion to nozzle-attached flame was investigated by increasing the fuel mole fraction. As the maximum flame temperature increases with decreasing liftoff height, the kinetic structure showed a transition behavior from autoignition to flame propagation of a lean premixed flame. © 2016 The Combustion Institute

  16. Absolute OH concentration profiles measurements in high pressure counterflow flames by coupling LIF, PLIF, and absorption techniques

    Science.gov (United States)

    Matynia, A.; Idir, M.; Molet, J.; Roche, C.; de Persis, S.; Pillier, L.

    2012-08-01

    A high-pressure combustion chamber enclosing counterflow burners was set-up at ICARE-CNRS laboratory. It allows the stabilization of flat twin premixed flames at atmospheric and high pressure. In this study, lean and stoichiometric methane/air counterflow premixed flames were studied at various pressures (0.1 MPa to 0.7 MPa). Relative OH concentration profiles were measured by Laser Induced Fluorescence. Great care was attached to the determination of the fluorescence signal by taking into account the line broadening and deexcitation by quenching which both arise at high pressure. Subsequently, OH profiles were calibrated in concentration by laser absorption technique associated with planar laser induced fluorescence. Results are successfully compared with literature. The good quality of the results attests of the experimental set-up ability to allow the study of flame structure at high pressure.

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

    Directory of Open Access Journals (Sweden)

    Richard Horrocks

    2016-08-01

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

  18. Advancing the Potential of Citizen Science for Urban Water Quality Monitoring: Exploring Research Design and Methodology in New York City

    Science.gov (United States)

    Hsueh, D.; Farnham, D. J.; Gibson, R.; McGillis, W. R.; Culligan, P. J.; Cooper, C.; Larson, L.; Mailloux, B. J.; Buchanan, R.; Borus, N.; Zain, N.; Eddowes, D.; Butkiewicz, L.; Loiselle, S. A.

    2015-12-01

    Citizen Science is a fast-growing ecological research tool with proven potential to rapidly produce large datasets. While the fields of astronomy and ornithology demonstrate particularly successful histories of enlisting the public in conducting scientific work, citizen science applications to the field of hydrology have been relatively underutilized. We demonstrate the potential of citizen science for monitoring water quality, particularly in the impervious, urban environment of New York City (NYC) where pollution via stormwater runoff is a leading source of waterway contamination. Through partnerships with HSBC, Earthwatch, and the NYC Water Trail Association, we have trained two citizen science communities to monitor the quality of NYC waterways, testing for a suite of water quality parameters including pH, turbidity, phosphate, nitrate, and Enterococci (an indicator bacteria for the presence of harmful pathogens associated with fecal pollution). We continue to enhance these citizen science programs with two additions to our methodology. First, we designed and produced at-home incubation ovens for Enterococci analysis, and second, we are developing automated photo-imaging for nitrate and phosphate concentrations. These improvements make our work more publicly accessible while maintaining scientific accuracy. We also initiated a volunteer survey assessing the motivations for participation among our citizen scientists. These three endeavors will inform future applications of citizen science for urban hydrological research. Ultimately, the spatiotemporally-rich dataset of waterway quality produced from our citizen science efforts will help advise NYC policy makers about the impacts of green infrastructure and other types of government-led efforts to clean up NYC waterways.

  19. Research Advances in Yak Meat Quality Characteristics%牦牛肉品质特性研究进展

    Institute of Scientific and Technical Information of China (English)

    万红玲; 雒林通; 吴建平

    2012-01-01

    The present paper reviewed yak meat quality characteristics from several aspects such as the composition,nutritive value,eating quality,processing quality and safety quality of yak meat in recent years.As an important source of meat protein in western China,yak meat has lots of advantages including safe,high protein content,low fat content,good amino acid balance and fatty acid profile.A perception that meat derived from yaks is less tender can be attributed to older harvested ages and without any distinction when sold to commercial market.Aging is an effective way to gain favorable changes in meat tenderness and other characteristics.%从牦牛肉化学组成、营养价值、食用品质、技术品质及卫生品质等方面总结了近年来人们对牦牛肉品质特性的研究。作为中国西部肉类蛋白的重要来源,牦牛肉具有安全、高蛋白、低脂肪、良好的氨基酸和脂肪酸组成等优点。而有关"牦牛肉较老"的观点可以归因于屠宰年龄较大并且没有进行分档,宰后成熟处理对提高牦牛肉嫩度及其它肉品质效果显著。

  20. Criteria for an advanced assessment of quality of moulding sands with organic binders and reclamation process products

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2013-05-01

    Full Text Available Reclamation of used moulding and core sands has been defined as a treatment of waste moulding refractory materials, enabling a recovery of at least one of the components having properties similar to those of the fresh component, and reuse for production of casting moulds and cores. However, at present, there is a lack of a reclaimed material assessment index, which could be applied to each type of moulding sand and reclaim. Modern investigation methods and equipment for the estimation of the quality of the moulding sands matrices with organic binders, in their circulation process, are presented in this paper. These methods, utilizing the special equipment combined with the author’s investigation methods developed in the Faculty of Foundry Engineering, AGH - University of Science and Technology, allow the better estimation of the matrix quality both in an aspect of its application as a fresh sand substitute in the preparation of moulding sands, and also with regard to the environmental protection. The most important criteria for the technological assessment of the reclaimed materials and the quality of sands with organic binders are presented in this paper.

  1. Advances in Research of Meat Quality Improvement%国外肉品品质改良研究进展

    Institute of Scientific and Technical Information of China (English)

    张哲奇; 李丹; 张凯华; 臧明伍

    2015-01-01

    Analysis of meat quality improvement is important for guiding meat production and improving the processing technology and quality. In this paper, the latest technologies in recent 5 years for meat quality improvement are reviewed with focus on the influence of dietary adjustment, slaughter and postmortem aging technologies, genetic modification of animals, heat processing, use of food additives and preservation process optimization on meat color, flavor and structure, aiming to provide references for future studies in this field.%研究肉品品质改良对于指导肉品生产、优化加工工艺、提高食品品质等具有重要意义。本文综述了近5年国外肉品品质改良的最新研究进展,主要分析了日粮调节、屠宰和成熟工艺、基因改良、热加工、食品添加剂使用和贮存工艺优化对肉品色泽、风味、组织状态等食用品质的影响,以期为国内相关研究提供参考和借鉴。

  2. Applications of Computer Vision for Assessing Quality of Agri-food Products: A Review of Recent Research Advances.

    Science.gov (United States)

    Ma, Ji; Sun, Da-Wen; Qu, Jia-Huan; Liu, Dan; Pu, Hongbin; Gao, Wen-Hong; Zeng, Xin-An

    2016-01-01

    With consumer concerns increasing over food quality and safety, the food industry has begun to pay much more attention to the development of rapid and reliable food-evaluation systems over the years. As a result, there is a great need for manufacturers and retailers to operate effective real-time assessments for food quality and safety during food production and processing. Computer vision, comprising a nondestructive assessment approach, has the aptitude to estimate the characteristics of food products with its advantages of fast speed, ease of use, and minimal sample preparation. Specifically, computer vision systems are feasible for classifying food products into specific grades, detecting defects, and estimating properties such as color, shape, size, surface defects, and contamination. Therefore, in order to track the latest research developments of this technology in the agri-food industry, this review aims to present the fundamentals and instrumentation of computer vision systems with details of applications in quality assessment of agri-food products from 2007 to 2013 and also discuss its future trends in combination with spectroscopy.

  3. Flame-in-gas-shield and miniature diffusion flame hydride atomizers for atomic fluorescence spectrometry: optimization and comparison

    International Nuclear Information System (INIS)

    A detailed optimization of relevant experimental parameters of two hydride atomizers for atomic fluorescence spectrometry: flame-in-gas-shield atomizer with a two-channel shielding unit and a standard atomizer for atomic fluorescence spectrometry, miniature diffusion flame, was performed. Arsine, generated by the reaction with NaBH4 in a flow injection arrangement, was chosen as the model hydride. Analytical characteristics of both the atomizers (sensitivity, noise, limits of detection) were compared. Under optimum conditions sensitivity obtained with flame-in-gas-shield atomizer was approximately twice higher than with miniature diffusion flame. The additional advantage of flame-in-gas-shield atomizer is significantly lower flame emission resulting in a better signal to noise ratio. The resulting arsenic limits of detection for miniature diffusion flame and flame-in-gas-shield atomizer were 3.8 ng l−1 and 1.0 ng l−1, respectively. - Highlights: • We optimized and compared two hydride atomizers for atomic fluorescence spectrometry. • Miniature diffusion flame and flame-in-gas-shield atomizer were optimized. • The limit of detection for arsenic was 1.0 ng l−1

  4. Analytical study in the mechanism of flame movement in horizontal tubes. II. Flame acceleration in smooth open tubes

    CERN Document Server

    Kazakov, Kirill A

    2013-01-01

    The problem of spontaneous acceleration of premixed flames propagating in open horizontal tubes with smooth walls is revisited. It is proved that in long tubes, this process can be considered quasi-steady, and an equation for the flame front position is derived using the on-shell description. Numerical solutions of this equation are found which show that as in the case of uniform flame movement, there are two essentially different regimes of flame propagation. In the type I regime, the flame speed and its acceleration are comparatively low, whereas the type II regime is characterized by significant flame acceleration that rapidly increases as the flame travels along the tube. A detailed comparison of the obtained results with the experimental data on flame acceleration in methane-air mixtures is given. In particular, it is confirmed that flames propagating in near-stoichiometric mixtures and mixtures near the limits of inflammability belong to the types II and I, respectively, whereas flames in transient mixt...

  5. Flame-in-gas-shield and miniature diffusion flame hydride atomizers for atomic fluorescence spectrometry: optimization and comparison

    Energy Technology Data Exchange (ETDEWEB)

    Marschner, Karel, E-mail: karel.marschner@biomed.cas.cz [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Charles University in Prague, Faculty of Science, Department of Analytical Chemistry, Albertov 8, 128 43 Prague (Czech Republic); Musil, Stanislav; Dědina, Jiří [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic)

    2015-07-01

    A detailed optimization of relevant experimental parameters of two hydride atomizers for atomic fluorescence spectrometry: flame-in-gas-shield atomizer with a two-channel shielding unit and a standard atomizer for atomic fluorescence spectrometry, miniature diffusion flame, was performed. Arsine, generated by the reaction with NaBH{sub 4} in a flow injection arrangement, was chosen as the model hydride. Analytical characteristics of both the atomizers (sensitivity, noise, limits of detection) were compared. Under optimum conditions sensitivity obtained with flame-in-gas-shield atomizer was approximately twice higher than with miniature diffusion flame. The additional advantage of flame-in-gas-shield atomizer is significantly lower flame emission resulting in a better signal to noise ratio. The resulting arsenic limits of detection for miniature diffusion flame and flame-in-gas-shield atomizer were 3.8 ng l{sup −1} and 1.0 ng l{sup −1}, respectively. - Highlights: • We optimized and compared two hydride atomizers for atomic fluorescence spectrometry. • Miniature diffusion flame and flame-in-gas-shield atomizer were optimized. • The limit of detection for arsenic was 1.0 ng l{sup −1}.

  6. Parametric Erosion Investigation: Propellant Adiabatic Flame Temperature

    Directory of Open Access Journals (Sweden)

    P. J. Conroy

    2002-01-01

    Full Text Available The influence of quasi-independent parameters and their potential influence on erosion in guns have been investigated. Specifically, the effects of flame temperature and the effect of assuming that the Lewis number (ratio of mass-to-heat transport to the surface, Le = 1, has been examined. The adiabatic flame temperature for a propellant was reduced by the addition of a diluent from a high temperature of 3843 K (similar to that of M9 down to 3004 K, which is near the value for M30A1 propellant. Mass fractions of critical species at the surface with and without the assumption of Le = 1 are presented, demonstrating that certain species preferentially reach the surface providing varied conditions for the surface reactions. The results for gun tube bore surface regression qualitatively agree with previous studies and with current experimental data.

  7. Computational and experimental study of laminar flames

    Energy Technology Data Exchange (ETDEWEB)

    Smooke, Mitchell [Yale Univ., New Haven, CT (United States)

    2015-05-29

    During the past three years, our research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in coflowing axisymmetric configurations. We have pursued both computational and experimental aspects of the research in parallel on both steady-state and time-dependent systems. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the steady-state and time-dependent boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. Previously, spontaneous Raman scattering, chemiluminescence, and laser-induced fluorescence were used to measure the temperature, major and minor species profiles. Particle image velocimetry (PIV) has been used to investigate velocity distributions and for calibration of time-varying flames. Laser-induced incandescence (LII) with an extinction calibration was used to determine soot volume fractions, while soot surface temperatures were measured with three-color optical pyrometry using a color digital camera. A blackbody calibration of the camera allows for determination of soot volume fraction as well, which can be compared with the LII measurements. More recently, we have concentrated on a detailed characterization of soot using a variety of techniques including time-resolved LII (TiRe-LII) for soot primary particles sizes, multi-angle light scattering (MALS) for soot radius of gyration, and spectrally-resolved line of sight attenuation (spec-LOSA). Combining the information from all of these soot measurements can be used to determine the soot optical properties, which are observed to vary significantly depending on spatial location and fuel dilution. Our goal has been to obtain a more fundamental understanding of the important fluid dynamic and chemical interactions in

  8. New developments in the theory of flame propagation

    Energy Technology Data Exchange (ETDEWEB)

    Sivashinsky, G.I. [City College of the City Univ. of New York, NY (United States)

    1996-12-31

    Two topics in combustion fluid mechanics are discussed. The first is a theory of the outward propagating spherical flame in the regime of well-developed hydrodynamic instability. In a qualitative agreement with experimental observations it is shown that the flame assumes a fractal-like wrinkled structure resulting in the overall burning rate acceleration. In contrast to hydrodynamically unstable flames, the expanding flame subject exclusively to the effect of diffusive instability does not indicate any disposition toward acceleration. The second topic concerns the dynamics of diffusively unstable flames subjected to radiative heat losses. At high enough heat losses the flame breaks up into separate self-propagating cap-like flamelets while a significant portion of the fuel remains unconsumed.

  9. Flames in fractal grid generated turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Goh, K H H; Hampp, F; Lindstedt, R P [Department of Mechanical Engineering, Imperial College, London SW7 2AZ (United Kingdom); Geipel, P, E-mail: p.lindstedt@imperial.ac.uk [Siemens Industrial Turbomachinery AB, SE-612 83 Finspong (Sweden)

    2013-12-15

    Twin premixed turbulent opposed jet flames were stabilized for lean mixtures of air with methane and propane in fractal grid generated turbulence. A density segregation method was applied alongside particle image velocimetry to obtain velocity and scalar statistics. It is shown that the current fractal grids increase the turbulence levels by around a factor of 2. Proper orthogonal decomposition (POD) was applied to show that the fractal grids produce slightly larger turbulent structures that decay at a slower rate as compared to conventional perforated plates. Conditional POD (CPOD) was also implemented using the density segregation technique and the results show that CPOD is essential to segregate the relative structures and turbulent kinetic energy distributions in each stream. The Kolmogorov length scales were also estimated providing values {approx}0.1 and {approx}0.5 mm in the reactants and products, respectively. Resolved profiles of flame surface density indicate that a thin flame assumption leading to bimodal statistics is not perfectly valid under the current conditions and it is expected that the data obtained will be of significant value to the development of computational methods that can provide information on the conditional structure of turbulence. It is concluded that the increase in the turbulent Reynolds number is without any negative impact on other parameters and that fractal grids provide a route towards removing the classical problem of a relatively low ratio of turbulent to bulk strain associated with the opposed jet configuration. (paper)

  10. Quality-of-Life-Adjusted Survival Analysis of Concurrent Chemo Radiotherapy for Locally Advanced (Nonmetastatic) Nasopharyngeal Cancer

    International Nuclear Information System (INIS)

    Purpose: To assess whether the benefits of adding cisplatin (CDDP) concurrent with radiotherapy, followed by adjuvant CDDP and fluorouracil, justifies the toxicity cost for nasopharyngeal cancer (NPC) using the quality-adjusted time without symptoms or toxicity (Q-TWiST) approach. Methods and Materials: One hundred seven patients treated with radiotherapy (RT) and 111 with concurrent chemotherapy and radiotherapy (CRT) were analyzed. The overall survival was divided into three health states: time on active treatment only, during which any subjective nonhematologic toxic event of grade > = 3 was reported; time without symptoms of disease relapse; or treatment and time following first disease RELapse. The relative advantage of CRT and RT was examined by conducting the analysis cumulatively at restriction times 3, 6, 24, 36, 48 months. Results: At 48 months, the improvement in disease-free survival was 14.4% for CRT, whereas that for overall survival was 18.9%. The differences in Q-TWiST were -0.4, -0.7, 0.1, 1.6, and 3.6 months at 3, 6, 24, 36, and 48 months, respectively, with positive differences favoring CRT. At 24 months, the difference in Q-TWiST began to favor CRT. At 36 months, CRT may be the preferred option from the patient's viewpoint if the time spent in the REL state is valued to be <0.83, with the value of perfect health being 1. Finally, Q-TWiST accumulated within 48 months indicated a significant advantage in quality-adjusted survival time for CRT (p = 0.020). Conclusion: Irrespective of how patients valued periods of toxicity and delayed disease progression, concurrent chemotherapy and radiotherapy offered NPC patients significantly more quality-adjusted survival than radiotherapy alone in the long term.

  11. Effects Of Electric Field On Hydrocarbon-Fueled Flames

    Science.gov (United States)

    Yuan, Z.-G.; Hegde, U.

    2003-01-01

    It has been observed that flames are susceptible to electric fields that are much weaker than the breakdown field strength of the flame gases. When an external electric field is imposed on a flame, the ions generated in the flame reaction zone drift in the direction of the electric forces exerted on them. The moving ions collide with the neutral species and change the velocity distribution in the affected region. This is often referred to as ionic wind effect. In addition, the removal of ions from the flame reaction zone can alter the chemical reaction pathway of the flame. On the other hand, the presence of space charges carried by moving ions affects the electric field distribution. As a result, the flame often changes its shape, location and color once an external electric field is applied. The interplay between the flame movement and the change of electric field makes it difficult to determine the flame location for a given configuration of electrodes and fuel source. In normal gravity, the buoyancy-induced flow often complicates the problem and hinders detailed study of the interaction between the flame and the electric field. In this work, the microgravity environment established at the 2.2 Second Drop Tower at the NASA Glenn Research Center is utilized to effectively remove the buoyant acceleration. The interaction between the flame and the electric field is studied in a one-dimensional domain. A specially designed electrode makes flame current measurements possible; thus, the mobility of ions, ion density, and ionic wind effect can be evaluated.

  12. Heat transfers from gaseous fuel - oxygen flames to metals

    Energy Technology Data Exchange (ETDEWEB)

    Guelen, J.; Kadirgan, N.; Sarac, A. (Yildiz Univ., Istanbul (TR). Dept. of Chemical Engineering)

    1991-01-01

    Because the flames produced by burning gaseous fuels with oxygen are too hot (3000{sup o}C), the heat transfers from these flames to metals cannot be investigated by classical methods. In the present study, the validity of a method depending on measuring the cutting time has been explored in order to compare the effectiveness of premixed gaseous fuel-oxygen flames from a heat transfer point of view. (author).

  13. Measurements of turbulent premixed flame dynamics using cinema stereoscopic PIV

    Science.gov (United States)

    Steinberg, Adam M.; Driscoll, James F.; Ceccio, Steven L.

    2008-06-01

    A new experimental method is described that provides high-speed movies of turbulent premixed flame wrinkling dynamics and the associated vorticity fields. This method employs cinema stereoscopic particle image velocimetry and has been applied to a turbulent slot Bunsen flame. Three-component velocity fields were measured with high temporal and spatial resolutions of 0.9 ms and 140 μm, respectively. The flame-front location was determined using a new multi-step method based on particle image gradients, which is described. Comparisons are made between flame fronts found with this method and simultaneous CH-PLIF images. These show that the flame contour determined corresponds well to the true location of maximum gas density gradient. Time histories of typical eddy-flame interactions are reported and several important phenomena identified. Outwardly rotating eddy pairs wrinkle the flame and are attenuated at they pass through the flamelet. Significant flame-generated vorticity is produced downstream of the wrinkled tip. Similar wrinkles are caused by larger groups of outwardly rotating eddies. Inwardly rotating pairs cause significant convex wrinkles that grow as the flame propagates. These wrinkles encounter other eddies that alter their behavior. The effects of the hydrodynamic and diffusive instabilities are observed and found to be significant contributors to the formation and propagation of wrinkles.

  14. Cinema particle image velocimetry investigation of turbulent jet flame stabilization

    Science.gov (United States)

    Upatnieks, Ansis

    A new cinema PIV system was developed and used to study the physical phenomena of non-premixed turbulent jet flame stabilization. The system offers an unprecedented combination of image acquisition rate (8000/s), sequence length (4000) and resolution (equivalent to 1K x 1.5K pixels) that provides finely resolved yet extraordinarily lengthy time histories of the evolution of velocity fields in laboratory-scale gas-phase turbulent flows. These measurements provide quantitative information concerning the dynamics of turbulence and combustion that is not available from conventional experimental techniques or computational simulations. For example, time histories of the interaction between turbulent vortex structures and the flame thermal boundary are observed. Gas and flame velocities are obtained simultaneously, yielding direct measurements of flame propagation velocities. The gas and flame velocities are highly correlated, suggesting strong interaction between the velocity field and the flame. The gas and propagation velocities at the flame base remain close to premixed laminar burning velocities (SL), which are three to four times smaller than the velocities in corresponding non-reacting cases. Strong reverse flow is observed upstream of the flame base, suggesting that the velocity reduction is caused by heat release-induced dilatation. These observations suggest that the dilatation velocity field plays a dominant role in stabilization by reducing incident gas velocities to levels at which laminar premixed, triple, or edge flames can be sustained.

  15. Active Control for Statistically Stationary Turbulent PremixedFlame Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Bell, J.B.; Day, M.S.; Grcar, J.F.; Lijewski, M.J.

    2005-08-30

    The speed of propagation of a premixed turbulent flame correlates with the intensity of the turbulence encountered by the flame. One consequence of this property is that premixed flames in both laboratory experiments and practical combustors require some type of stabilization mechanism to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. Furthermore, the stabilization introduces additional fluid mechanical complexity into the overall combustion process that can complicate the analysis of fundamental flame properties. To circumvent these difficulties we introduce a feedback control algorithm that allows us to computationally stabilize a turbulent premixed flame in a simple geometric configuration. For the simulations, we specify turbulent inflow conditions and dynamically adjust the integrated fueling rate to control the mean location of the flame in the domain. We outline the numerical procedure, and illustrate the behavior of the control algorithm on methane flames at various equivalence ratios in two dimensions. The simulation data are used to study the local variation in the speed of propagation due to flame surface curvature.

  16. Effects of buoyancy on gas jet diffusion flames

    Science.gov (United States)

    Bahadori, M. Yousef; Edelman, Raymond B.

    1993-01-01

    The objective of this effort was to gain a better understanding of the fundamental phenomena involved in laminar gas jet diffusion flames in the absence of buoyancy by studying the transient phenomena of ignition and flame development, (quasi-) steady-state flame characteristics, soot effects, radiation, and, if any, extinction phenomena. This involved measurements of flame size and development, as well as temperature and radiation. Additionally, flame behavior, color, and luminosity were observed and recorded. The tests quantified the effects of Reynolds number, nozzle size, fuel reactivity and type, oxygen concentration, and pressure on flame characteristics. Analytical and numerical modeling efforts were also performed. Methane and propane flames were studied in the 2.2 Second Drop Tower and the 5.18-Second Zero-Gravity Facility of NASA LeRC. In addition, a preliminary series of tests were conducted in the KC-135 research aircraft. Both micro-gravity and normal-gravity flames were studied in this program. The results have provided unique and new information on the behavior and characteristics of gas jet diffusion flames in micro-gravity environments.

  17. Measurement of flame emissivity of gasoline pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Sudheer, S. [Department of Mechanical Engineering, Indian Institute of Technology, Bombay, Powai, Mumbai - 400 076 (India); Prabhu, S.V., E-mail: svprabhu@iitb.ac.i [Department of Mechanical Engineering, Indian Institute of Technology, Bombay, Powai, Mumbai - 400 076 (India)

    2010-10-15

    Major engineering parameter of interest in open pool fires is flame emissivity. Mass burning rate is measured for gasoline pool fires of pool diameters 0.3 m, 0.5 m, 0.7 m and 1.0 m. Flame emissivities of the pool fires are inferred from the mass burning rate. It is observed that the emissivity of the flame increases with the diameter. The mean optical thickness of gasoline pool fires is found to be 1.52 m{sup -1}. Using thermography, emissivity variation with the height of the flame of gasoline pool fire is investigated for diameters of 0.3 m, 0.5 m, 0.7 m and 1.0 m. In this thermography technique, multiple black bodies are placed at different heights behind the flame. Emissivity of the flame at the flame tip is lower than that at the base of the pool fire. The average value of the flame emissivity measured using thermography is comparable with the flame emissivity inferred from the mass burning rate value.

  18. Flame fronts in Supernovae Ia and their pulsational stability

    CERN Document Server

    Glazyrin, S I; Dolgov, A D

    2013-01-01

    The structure of the deflagration burning front in type Ia supernovae is considered. The parameters of the flame are obtained: its normal velocity and thickness. The results are in good agreement with previous work of different authors. After that the question of pulsational instability of the flame subject to plane perturbations is considered. The flame can be unstable if hydrodynamics can be ignored, e.g. in solid-body propellants. However, with account of hydrodynamics we find that the flame in type Ia supernovae is pulsationally stable with realistic parameters of reactions and thermal conduction.

  19. Product engineering by high-temperature flame synthesis

    DEFF Research Database (Denmark)

    Johannessen, Tue; Johansen, Johnny; Mosleh, Majid;

    High-temperature flame processes can be applied as a tool for chemical product engineering. The general principle behind flame synthesis is the decomposition/oxidation of evaporated metal-precursors in a flame, thereby forming metal oxide monomers which nucleate, aggregate, and - to some extent...... hardware by direct deposition of catalysts on process equipment • Modifications of the substrate surfaces to obtain good adhesion during flame-coating • Formation of membrane layers by gas-phase deposition of nano-particles • Catalyst deposition in micro-reactors for rapid catalyst screening...

  20. Research on Alkaline Filler Flame-Retarded Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    HU Shuguang; ZHANG Houji; WANG Jiaolan

    2006-01-01

    Used as flame retardant of tunnel asphalt pavement, organic bromides produce a large amount of poisons and smoke in construction and flame retardation stage. The alkaline filler was found to replace mineral filler, and the flame-retarded asphalt mixtures were produced. Experimental results show that these asphalt mixtures are smoke restrained; the performances and construction technology of asphalt pavement are not influenced; also the alkaline filler is of low-price. So this kind of flame-retarded asphalt mixtures is suitable for tunnel pavement.

  1. Analytical Interaction of the Acoustic Wave and Turbulent Flame

    Institute of Scientific and Technical Information of China (English)

    TENG Hong-Hui; JIANG Zong-Lin

    2007-01-01

    A modified resonance model of a weakly turbulent flame in a high-frequency acoustic wave is derived analytically.Under the mechanism of Darrieus-Landau instability, the amplitude of flame wrinkles, which is as functions of turbulence. The high perturbation wave number makes the resonance easier to be triggered but weakened with respect to the extra acoustic wave. In a closed burning chamber with the acoustic wave induced by the flame itself, the high perturbation wave number is to restrain the resonance for a realistic flame.

  2. Measurements of turbulent premixed flame dynamics using cinema stereoscopic PIV

    Energy Technology Data Exchange (ETDEWEB)

    Steinberg, Adam M.; Driscoll, James F. [University of Michigan, Department of Aerospace Engineering, Ann Arbor, MI (United States); Ceccio, Steven L. [University of Michigan, Department of Mechanical Engineering, Ann Arbor, MI (United States)

    2008-06-15

    A new experimental method is described that provides high-speed movies of turbulent premixed flame wrinkling dynamics and the associated vorticity fields. This method employs cinema stereoscopic particle image velocimetry and has been applied to a turbulent slot Bunsen flame. Three-component velocity fields were measured with high temporal and spatial resolutions of 0.9 ms and 140{mu}m, respectively. The flame-front location was determined using a new multi-step method based on particle image gradients, which is described. Comparisons are made between flame fronts found with this method and simultaneous CH-PLIF images. These show that the flame contour determined corresponds well to the true location of maximum gas density gradient. Time histories of typical eddy-flame interactions are reported and several important phenomena identified. Outwardly rotating eddy pairs wrinkle the flame and are attenuated at they pass through the flamelet. Significant flame-generated vorticity is produced downstream of the wrinkled tip. Similar wrinkles are caused by larger groups of outwardly rotating eddies. Inwardly rotating pairs cause significant convex wrinkles that grow as the flame propagates. These wrinkles encounter other eddies that alter their behavior. The effects of the hydrodynamic and diffusive instabilities are observed and found to be significant contributors to the formation and propagation of wrinkles. (orig.)

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

    Institute of Scientific and Technical Information of China (English)

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

    2012-01-01

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

  4. Radiation Heat Transfer in Particle-Laden Gaseous Flame: Flame Acceleration and Triggering Detonation

    OpenAIRE

    Liberman, M. A.; Ivanov, M. F.; Kiverin, A. D.

    2015-01-01

    In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase ...

  5. A Novel Process for High-efficient Synthesis of One-dimensional Carbon Nanoraaterials from Flames

    Institute of Scientific and Technical Information of China (English)

    Xiang QI; Jun ZHANG; Chunxu PAN

    2008-01-01

    The substrate pre-treatment plays a key role in obtaining hollow-cored carbon nanotubes (CNTs) and solidcored carbon nanofibers (CNFs) from flames. This paper introduces a simply and high-efficient process by coating a NiSO4 or FeSO4 layer on the substrate as catalyst precursors. Comparing with the regular pretreatment methods, the present experiments showed that the coating pre-treatment provided the following advantages: 1) greatly shortening the synthesis time; 2) available variant substrates and carbon sources; 3) narrowing the diameters distribution. The sulfate is considered to be a crucial factor at the growth of CNTs and CNFs, because it increases the surface energy of catalyst particles and the surface specificity of sulfurs action in metallic grains. This novel process provides a possibility for high quality and mass production of CNTs and CNFs from flames.

  6. Litter decomposition over broad spatial and long time scales investigated by advanced solid-state NMR: insight into effects of climate, litter quality, and time

    Science.gov (United States)

    Mao, J.; Chen, N.; Harmon, M. E.; Li, Y.; Cao, X.; Chappell, M.

    2012-12-01

    Advanced 13C solid-state NMR techniques were employed to study the chemical structural changes of litter decomposition across broad spatial and long time scales. The fresh and decomposed litter samples of four species (Acer saccharum (ACSA), Drypetes glauca (DRGL), Pinus resinosa (PIRE), and Thuja plicata (THPL)) incubated for up to 10 years at four sites under different climatic conditions (from Arctic to tropical forest) were examined. Decomposition generally led to an enrichment of cutin and surface wax materials, and a depletion of carbohydrates causing overall composition to become more similar compared with original litters. However, the changes of main constituents in the four litters were inconsistent with the four litters following different pathways of decomposition at the same site. As decomposition proceeded, waxy materials decreased at the early stage and then gradually increased in PIRE; DRGL showed a significant depletion of lignin and tannin while the changes of lignin and tannin were relative small and inconsistent for ACSA and THPL. In addition, the NCH groups, which could be associated with either fungal cell wall chitin or bacterial wall petidoglycan, were enriched in all litters except THPL. Contrary to the classic lignin-enrichment hypothesis, DRGL with low-quality C substrate had the highest degree of composition changes. Furthermore, some samples had more "advanced" compositional changes in the intermediate stage of decomposition than in the highly-decomposed stage. This pattern might be attributed to the formation of new cross-linking structures, that rendered substrates more complex and difficult for enzymes to attack. Finally, litter quality overrode climate and time factors as a control of long-term changes of chemical composition.

  7. Validation of the quality of life-radiation therapy instrument (QOL-RTI) in patients receiving definitive radiation therapy for locally advanced prostate cancer

    International Nuclear Information System (INIS)

    Purpose/Objective: The incidence of prostate cancer has tripled over the last 10 years, doubled over the last four years and continues to increase. A common method of treating prostate cancer is with external beam radiotherapy with or without hormones. Accurate and comprehensive documentation through prospective studies with long term follow-up is necessary to reduce the negative impact of treatment on a patient's quality of life. While it is increasingly recognized that radiation therapy treatment for prostate cancer may result in permanent alteration of the patient's quality of life, the extent and timing of this change in quality of life has not been adequately investigated in a comprehensive and prospective manner. Furthermore, there are limited instruments developed for use with patients undergoing definitive radiotherapy. The purpose of this paper is to report on the validation of the Quality of Life Radiation Therapy Instrument (QOL-RTI), a 24-item visual analogue general quality of life tool developed for use with patients receiving radiotherapy. Materials and Methods: Health related quality of life was assessed in a prospective study of 62 patients treated with either combined hormonal therapy (HT) plus external beam radiotherapy (EBRT) or EBRT alone for locally advanced prostate cancer. Quality life was measured prospectively before, during, and after radiation therapy. Results: The estimated reliability of the subscales was assessed with coefficient alpha which ranged from 0.57 to 0.68. Internal consistency was calculated using initial questionnaires for the entire sample, yielding a Cronbach's alpha of 0.82. Test-retest produced a correlation coefficient of 0.75 (p<0.0001) [n=60]. Construct validity was assessed by a repeated measures design to look for time effect, group effect, group and time interaction effect. We examined quality of life total scores, subscale total scores and performance status scores for patients who were treated with HT+ EBRT and

  8. [The certification of advanced therapy medicinal products. A quality label for product development in small and medium-sized enterprises].

    Science.gov (United States)

    Berger, A; Schüle, S; Flory, E

    2011-07-01

    Advanced therapy medicinal products (ATMPs) are gene therapy, cell therapy, and tissue engineered products. To gain access to the market within the European Union, ATMPs must be authorized by the European Commission (EC). Especially for small and medium-sized enterprises (SMEs), the European centralized procedure of marketing authorization that is conducted by the European Medicines Agency (EMA) constitutes a major challenge, because SMEs often have little experience with regulatory procedures and many have limited financial possibilities. To tackle these challenges, a certification procedure exclusively for SMEs and their ATMP development was introduced by the EC. Independently from a marketing authorization application, development and/or production processes can be certified. An issued certificate demonstrates that the respective process meets the current regulatory and scientific requirements of the EMA, representing a valuable milestone for putative investors and licensees. This article highlights the background, the detailed procedure, the minimum requirements, as well as the costs of certification, while giving further noteworthy guidance for interested parties.

  9. Investigations of two-phase flame propagation under microgravity conditions

    Science.gov (United States)

    Gokalp, Iskender

    2016-07-01

    Investigations of two-phase flame propagation under microgravity conditions R. Thimothée, C. Chauveau, F. Halter, I Gökalp Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), CNRS, 1C Avenue de la Recherche Scientifique, 45071 Orléans Cedex 2, France This paper presents and discusses recent results on two-phase flame propagation experiments we carried out with mono-sized ethanol droplet aerosols under microgravity conditions. Fundamental studies on the flame propagation in fuel droplet clouds or sprays are essential for a better understanding of the combustion processes in many practical applications including internal combustion engines for cars, modern aircraft and liquid rocket engines. Compared to homogeneous gas phase combustion, the presence of a liquid phase considerably complicates the physico-chemical processes that make up combustion phenomena by coupling liquid atomization, droplet vaporization, mixing and heterogeneous combustion processes giving rise to various combustion regimes where ignition problems and flame instabilities become crucial to understand and control. Almost all applications of spray combustion occur under high pressure conditions. When a high pressure two-phase flame propagation is investigated under normal gravity conditions, sedimentation effects and strong buoyancy flows complicate the picture by inducing additional phenomena and obscuring the proper effect of the presence of the liquid droplets on flame propagation compared to gas phase flame propagation. Conducting such experiments under reduced gravity conditions is therefore helpful for the fundamental understanding of two-phase combustion. We are considering spherically propagating two-phase flames where the fuel aerosol is generated from a gaseous air-fuel mixture using the condensation technique of expansion cooling, based on the Wilson cloud chamber principle. This technique is widely recognized to create well-defined mono-size droplets

  10. Diffusion Flame Extinction in a Low Strain Flow

    Science.gov (United States)

    Sutula, Jason; Jones, Joshua; Torero, Jose L.; Borlik, Jeffrey; Ezekoye, Ofodike A.

    1997-01-01

    Diffusion flames are of great interest in fire safety and many industrial processes. Many parameters significantly affect the flame structure, shape and stability, of particular importance are the constraints imposed by geometrical boundaries. Physical boundaries determine the characteristics of the flow, affect heat, fuel, and oxidizer transport from and towards the flame and can act as heat sinks or heat sources. As a result, the existence of a flame, its shape and nature are intimately related to the geometrical characteristics of the environment that surrounds it. The counter-flow configuration provides a constant strain flow, therefore, is ideal to study the structure of diffusion flames. Most studies have concentrated on the high velocity, high strain limit, since buoyantly induced instabilities will disintegrate the planar flame as the velocity decreases. Only recently, experimental studies in micro-gravity conditions have begun to explore the low strain regimes. The main objective of these on-going studies is to determine the effect of radiative heat losses and variable strain on the structure and radiation-induced extinction of diffusion flames. For these programs, size, geometry, and experimental conditions have been chosen to keep the flame unaffected by the physical boundaries. Whether is the burning of condensed or gaseous fuels, for most real situations the boundaries impose a significant effect on the nature of the flame. There is, therefore, a need to better understand the effect that geometrical constraints (i.e. flow nonperpendicular to a fuel surface, heat losses to the boundaries, etc.) might have on the final characteristics of a diffusion flame. Preliminary experiments have shown that, in the absence of gravity, and depending on the distance from the flame to the boundary, three characteristically different regimes can be observed. Close to the boundary, the flame is parabolic, very thin and blue, almost soot-less. Diffusion is the main

  11. Nonpremixed flame in a counterflow under electric fields

    KAUST Repository

    Park, Daegeun

    2016-05-08

    Electrically assisted combustion has been studied in order to control or improve flame characteristics, and emphasizing efficiency and emission regulation. Many phenomenological observations have been reported on the positive impact of electric fields on flame, however there is a lack of detailed physical mechanisms for interpreting these. To clarify the effects of electric fields on flame, I have investigated flame structure, soot formation, and flow field with ionic wind electrical current responses in nonpremixed counterflow flames. The effects of direct current (DC) electric field on flame movement and flow field was also demonstrated in premixed Bunsen flames. When a DC electric field was applied to a lower nozzle, the flames moved toward the cathode side due to Lorentz force action on the positive ions, soot particles simultaneously disappeared completely and laser diagnostics was used to identify the results from the soot particles. To understand the effects of an electric field on flames, flow visualization was performed by Mie scattering to check the ionic wind effect, which is considered to play an important role in electric field assisted combustion. Results showed a bidirectional ionic wind, with a double-stagnant flow configuration, which blew from the flame (ionic source) toward both the cathode and the anode. This implies that the electric field affects strain rate and the axial location of stoichiometry, important factors in maintaining nonpremixed counterflow flames; thus, soot formation of the counterflow flame can also be affected by the electric field. In a test of premixed Bunsen flames having parallel electrodes, flame movement toward the cathode and bidirectional ionic wind were observed. Using PIV measurement it was found that a created radial velocity caused by positive ions (i.e. toward a cathode), was much faster than the velocity toward the anode. Even in a study of alternating current (AC) electric fields, bidirectional ionic wind could

  12. Effect of turbulence on extinction of counterflow diffusion flame

    Energy Technology Data Exchange (ETDEWEB)

    Tsuji, Hiroshi; Yoshida, Akira; Endo, Nobuyuki [Tokyo Denki Univ. (Japan). Dept. of Mechanical Engineering

    1994-12-31

    A laminar counterflow diffusion flame established in the forward stagnation region of a porous cylinder has been used widely for the laminar flame studies. In the present study, this flame was applied to investigating the extinction of a diffusion flame due to air stream turbulence. Propane or methane was ejected from a 30-mm porous cylinder. The turbulence was given to the counterflowing air stream by perforated plates. The results of this study show that the air stream turbulence causes large-scale distortions with small amplitude on the apparently laminar diffusion flame, and the time-averaged thickness of this flame is three times as large as the purely laminar flame. Even if the air stream becomes turbulent, there exists a critical stagnation velocity gradient beyond which the flame can never be stabilized, however large the fuel ejection velocity is. Local extinction near the stagnation region always leads to global extinction of the whole flame. As expected, the critical velocity gradient decreases as the turbulence intensity increases. This flame is subjected to the sum of the bulk stretch rate exerted by the mean flow and the turbulent stretch rate exerted by small eddies of Kolmogorov scale. The critical total stretch rate at which the extinction occurs is nearly constant for each fuel for all turbulence conditions tested in the present study and coincides with the critical stagnation velocity gradient of the laminar diffusion flame, that is, the total stretch rate without turbulence. This fact suggests that large-scale eddies are not so effective for the local extinction and that the chemical reaction that occurs in molecular scale is not affected by small eddies of the Kolmogorov scale.

  13. Gaseous Non-Premixed Flame Research Planned for the International Space Station

    Science.gov (United States)

    Stocker, Dennis P.; Takahashi, Fumiaki; Hickman, J. Mark; Suttles, Andrew C.

    2014-01-01

    Thus far, studies of gaseous diffusion flames on the International Space Station (ISS) have been limited to research conducted in the Microgravity Science Glovebox (MSG) in mid-2009 and early 2012. The research was performed with limited instrumentation, but novel techniques allowed for the determination of the soot temperature and volume fraction. Development is now underway for the next experiments of this type. The Advanced Combustion via Microgravity Experiments (ACME) project consists of five independent experiments that will be conducted with expanded instrumentation within the stations Combustion Integrated Rack (CIR). ACMEs goals are to improve our understanding of flame stability and extinction limits, soot control and reduction, oxygen-enriched combustion which could enable practical carbon sequestration, combustion at fuel lean conditions where both optimum performance and low emissions can be achieved, the use of electric fields for combustion control, and materials flammability. The microgravity environment provides longer residence times and larger length scales, yielding a broad range of flame conditions which are beneficial for simplified analysis, e.g., of limit behaviour where chemical kinetics are important. The detailed design of the modular ACME hardware, e.g., with exchangeable burners, is nearing completion, and it is expected that on-orbit testing will begin in 2016.

  14. Developing a Patient Care Co-ordination Centre in Trafford, England: lessons from the International Foundation for Integrated Care (IFIC/Advancing Quality Alliance integrated care fellowship experience

    Directory of Open Access Journals (Sweden)

    Michael Gregory

    2015-05-01

    Full Text Available The NHS and Social Care in England are facing one of the biggest financial challenges for a generation. Commissioners and providers need to work on collaborative schemes to manage the increasing demand on health and social care within a period of financial constraint. Different forms of care co-ordination have been developed at different levels across the world.In the north-west of England, the Trafford health and social care economy have been working through a competitive dialogue process with industry to develop an innovative and dynamic solution to deliver seamless co-ordination for all patients and service users. The strategy is to develop a new Patient Care Co-ordination Centre, which will be responsible for the delivery of co-ordinated, quality care. The Patient Care Co-ordination Centre will work at clinical, service, functional and community levels across multiple providers covering risk stratification, preventative, elective and unscheduled care.I am the clinical lead for the Patient Care Co-ordination Centre and during my year as an Advancing Quality Alliance Integrated Care Fellow, I have had the opportunity to study examples of care coordination from UK and international sites. The learning from these visits has been assimilated into the design process of the Patient Care Co-ordination Centre.

  15. Advances in performance and beam quality of 9xx-nm laser diodes tailored for efficient fiber coupling

    Science.gov (United States)

    Lauer, Christian; König, Harald; Grönninger, Günther; Hein, Sebastian; Gomez-Iglesias, Alvaro; Furitsch, Michael; Maric, Josip; Kissel, Heiko; Wolf, Paul; Biesenbach, Jens; Strauss, Uwe

    2012-03-01

    The impact of new direct-diode and fiber laser systems on industrial manufacturing drives the demand for highbrightness diode laser pump sources suitable for simple fiber coupling with high efficiency. Within the German funded project HEMILAS laser mini-bars with different bar geometries and small fill factors were investigated. We present results on 9xx nm bars with tailored beam parameter products for simplified coupling to fibers with core diameters of 200μm and 300μm with a numerical aperture of 0.22 and compare beam quality parameters, brightness, conversion efficiency, and thermal performance of different bar designs. Optimized epitaxy structures yield conversion efficiency maxima above 66%. The slow axis divergence angle of mini-bars with a fill factor of 10% featuring five 100μm wide and 4mm long emitters based on this epitaxy structure stays below 7°, which corresponds to a beam parameter product of 15mm mrad, up to very high output power of over 45W. This result was achieved for mounting on actively cooled submounts using hard solder. A similar bar with 5mm cavity length and using soft soldering reached an output power of 60W at the same beam parameter product. At 4mm cavity length, no COMD failures were observed up to currents exceeding the thermal rollover and the maximum output cw power was 95W.

  16. Effect of Flame Conditions on Crystalline Structure of TiO2 in Liquid Flame Spraying

    Institute of Scientific and Technical Information of China (English)

    LI Chang-jiu; YANG Guan-jun; WANG Yu-yue

    2004-01-01

    Nanostructured TiO2 is a most promising functional ceramic owing to its potential utilization in photocatalytical, optical and electrical applications. Nanostructured TiO2 coating was deposited through thermal spraying with liquid feedstock. Two types of crystalline structures were present in the synthesized TiO2 coating including anatase phase and rutile phase.The effect of spray flame conditions on the crystalline structure was investigated in order to control the crystalline structure of the coating. The results showed that spray distance, flame power and precursor concentration in the liquid feedstock significantly influenced phase constitutions and grain size in the coating. Anatase phase was formed at spray distance from 150 to 250mm, while rutile phase was evidently observed in the coating deposited at 100 mm. The results suggested that anatase phase was firstly formed in the coating, and rutile phase resulted from the transformation of the deposited anatase phase. The phase transformation from anatase to rutile occurred through the annealing effect of spraying flame. The control of the phase formation can be realized through flame condition and spray distance.

  17. In-Flame Characterization of a 30 MWth Bio-Dust Flame

    DEFF Research Database (Denmark)

    Johansen, Joakim Myung; Jensen, Peter Arendt; Clausen, Sønnik;

    This work presents a comprehensive flame characterization campaign on an operating full-scale Danish power plant. Amagerværket Unit 1 (AMV1, 350 MWth, 12 identical burners on 3 burner levels) is 100 % fuelled with wood dust burned in suspension and stabilized by swirling flows in a triple...

  18. Study on turbulent fluctuations in diffusion flames using laser induced fluorescence. Doctoral thesis; Studie van turbulente fluctuaties in diffusievlammen met gebruik van laser geinduceerde fluorescentie

    Energy Technology Data Exchange (ETDEWEB)

    de Vries, J.E.

    1994-11-15

    Even with the fastest computers of the day, detailed chemistry modelling can only be applied to turbulent flames with simple geometry, and not to flames in industrial furnaces which generally have complex geometries. The power of the laboratory scale turbulent flames we studied is about 25 kW, compared to flame powers used in industry often ranging from 100 kW to several MW. In the Heat Transfer Group, several researchers collaborate to provide a description as complete as possible of turbulent co-current nonpremixed natural gas flames produced by a burner designed in the Heat Transfer Group. In total, we investigated six flames with different conditions. The aims of this study are to provide concentration measurements, including measurements of average concentrations and of quantities describing turbulent fluctuations of the species measured. The effect of turbulence on the concentrations is studied by varying the exit velocities, and the effect of chemistry by varying the exit flow temperature. In addition, we chose to measure NO seeded to the natural gas, to study the mixing of a conserved species by shear layer turbulence. These results uncover the qualities and shortcomings of the current models of turbulent combustion.

  19. CoFlame: A refined and validated numerical algorithm for modeling sooting laminar coflow diffusion flames

    Science.gov (United States)

    Eaves, Nick A.; Zhang, Qingan; Liu, Fengshan; Guo, Hongsheng; Dworkin, Seth B.; Thomson, Murray J.

    2016-10-01

    Mitigation of soot emissions from combustion devices is a global concern. For example, recent EURO 6 regulations for vehicles have placed stringent limits on soot emissions. In order to allow design engineers to achieve the goal of reduced soot emissions, they must have the tools to so. Due to the complex nature of soot formation, which includes growth and oxidation, detailed numerical models are required to gain fundamental insights into the mechanisms of soot formation. A detailed description of the CoFlame FORTRAN code which models sooting laminar coflow diffusion flames is given. The code solves axial and radial velocity, temperature, species conservation, and soot aggregate and primary particle number density equations. The sectional particle dynamics model includes nucleation, PAH condensation and HACA surface growth, surface oxidation, coagulation, fragmentation, particle diffusion, and thermophoresis. The code utilizes a distributed memory parallelization scheme with strip-domain decomposition. The public release of the CoFlame code, which has been refined in terms of coding structure, to the research community accompanies this paper. CoFlame is validated against experimental data for reattachment length in an axi-symmetric pipe with a sudden expansion, and ethylene-air and methane-air diffusion flames for multiple soot morphological parameters and gas-phase species. Finally, the parallel performance and computational costs of the code is investigated. Catalogue identifier: AFAU_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AFAU_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 94964 No. of bytes in distributed program, including test data, etc.: 6242986 Distribution format: tar.gz Programming language: Fortran 90, MPI. (Requires an Intel compiler). Computer: Workstations

  20. SU-C-BRD-05: Implementation of Incident Learning in the Safety and Quality Management of Radiotherapy: The Primary Experience in a New Established Program with Advanced Techniques

    International Nuclear Information System (INIS)

    Purpose: To explore the implementation and effectiveness of incident learning for the safety and quality of radiotherapy in a new established radiotherapy program with advanced technology. Methods: Reference to the consensus recommendations by American Association of Physicist in Medicine, an incident learning system was specifically designed for reporting, investigating, and learning of individual radiotherapy incidents in a new established radiotherapy program, with 4D CBCT, Ultrasound guided radiotherapy, VMAT, gated treatment delivered on two new installed linacs. The incidents occurring in external beam radiotherapy from February, 2012 to January, 2014 were reported. Results: A total of 33 reports were analyzed, including 28 near misses and 5 incidents. Among them, 5 originated in imaging for planning, 25 in planning, 1 in plan transfer, 1 in commissioning and 1 in treatment delivery. Among them, three near misses originated in the safety barrier of the radiotherapy process. In terms of error type, 1 incident was classified as wrong patient, 7 near misses/incidents as wrong site, 6 as wrong laterality, 5 as wrong dose, 7 as wrong prescription, and 7 as suboptimal plan quality. 5 incidents were all classified as grade 1/2 of dosimetric severity, 1 as grade 0, and the other 4 as grade 1 of medical severity. For the causes/contributory factors, negligence, policy not followed, inadequate training, failure to develop an effective plan, and communication contributed to 19, 15, 12, 5 and 3 near misses/incidents, respectively. The average incident rate per 100 patients treated was 0.4; this rate fell to 0.28% in the second year from 0.56% in the first year. The rate of near miss fell to 1.24% from 2.22%. Conclusion: Effective incident learning can reduce the occurrence of near miss/incidents, enhance the culture of safety. Incident learning is an effective proactive method for improving the quality and safety of radiotherapy

  1. SU-C-BRD-05: Implementation of Incident Learning in the Safety and Quality Management of Radiotherapy: The Primary Experience in a New Established Program with Advanced Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Yang, R; Wang, J [Peking University Third Hospital, Beijing, Beijing (China)

    2014-06-15

    Purpose: To explore the implementation and effectiveness of incident learning for the safety and quality of radiotherapy in a new established radiotherapy program with advanced technology. Methods: Reference to the consensus recommendations by American Association of Physicist in Medicine, an incident learning system was specifically designed for reporting, investigating, and learning of individual radiotherapy incidents in a new established radiotherapy program, with 4D CBCT, Ultrasound guided radiotherapy, VMAT, gated treatment delivered on two new installed linacs. The incidents occurring in external beam radiotherapy from February, 2012 to January, 2014 were reported. Results: A total of 33 reports were analyzed, including 28 near misses and 5 incidents. Among them, 5 originated in imaging for planning, 25 in planning, 1 in plan transfer, 1 in commissioning and 1 in treatment delivery. Among them, three near misses originated in the safety barrier of the radiotherapy process. In terms of error type, 1 incident was classified as wrong patient, 7 near misses/incidents as wrong site, 6 as wrong laterality, 5 as wrong dose, 7 as wrong prescription, and 7 as suboptimal plan quality. 5 incidents were all classified as grade 1/2 of dosimetric severity, 1 as grade 0, and the other 4 as grade 1 of medical severity. For the causes/contributory factors, negligence, policy not followed, inadequate training, failure to develop an effective plan, and communication contributed to 19, 15, 12, 5 and 3 near misses/incidents, respectively. The average incident rate per 100 patients treated was 0.4; this rate fell to 0.28% in the second year from 0.56% in the first year. The rate of near miss fell to 1.24% from 2.22%. Conclusion: Effective incident learning can reduce the occurrence of near miss/incidents, enhance the culture of safety. Incident learning is an effective proactive method for improving the quality and safety of radiotherapy.

  2. Using Quality of Life Measures in a Phase I Clinical Trial of Noni in Patients with Advanced Cancer to Select a Phase II Dose

    Science.gov (United States)

    Issell, Brian F.; Gotay, Carolyn C.; Pagano, Ian; Franke, A. Adrian

    2015-01-01

    Purpose We conducted a Phase I study of noni in patients with advanced cancer. Quality of life measures were examined as an alternate way to select a Phase II dose of this popular dietary supplement. Patients and Methods Starting at two capsules twice daily (2 grams), the dose suggested for marketed products, dose levels were escalated by 2 grams daily in cohorts of at least five patients until a maximum tolerated dose was found. Patients completed QLQ-C30 Quality of Life, and the Brief Fatigue Inventory (BFI), questionnaires at baseline and at four week intervals. Scopoletin was measured in blood and urine collected at baseline and at approximately four week intervals. Results Fifty-one patients were enrolled at seven dose levels. Seven capsules four times daily (14 grams) was the maximum tolerated dose. No dose limiting toxicity was found but four of eight patients at this level withdrew from the study due to the challenges of ingesting so many capsules. There was a dose response for self reported physical functioning and the control of pain and fatigue. Patients taking four capsules four times daily experienced less fatigue than patients taking lower or higher doses. A relationship between noni dose and blood and urinary scopoletin concentrations was found. Conclusion Measuring quality of life to determine a dose for subsequent Phase II testing is feasible. A noni dose of four capsules four times daily (8 grams) is recommended for Phase II testing where controlling fatigue and maintaining physical function is the efficacy of interest. Scopoletin is a measurable noni ingredient for pharmacokinetic studies in patients with cancer. PMID:22435516

  3. Nanotechnology finding its way into flame retardancy

    Energy Technology Data Exchange (ETDEWEB)

    Schartel, Bernhard, E-mail: bernhard.schartel@bam.de [BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)

    2014-05-15

    Nanotechnology is one of the key technologies of the 21{sup st} century. The exploitation of 'new' effects that arise from materials structured on the nano-scale has also been proposed successfully for flame retardancy of polymers since the end of the 90s. Of all of the approaches these include, at this time the use of nanocomposites offers the best potential for industrial application, also some other ideas are sketched, such as using electrospun nanofibers mats or layer-by-layer deposits as protection coatings, as well as sub-micrometer multilayer coatings as effective IR-mirrors. The general phenomena, inducing a flow limit in the pyrolysing melt and changing the fire residue, are identified in nanocomposites. Key experiments are performed such as quasi online investigation of the protection layer formation to understand what is going on in detail. The flame retardancy mechanisms are discussed and their impact on fire behaviour quantified. With the latter, the presentation pushes forward the state of the art. For instance, the heat shielding is experimentally quantified for a layered silicate epoxy resin nanocomposite proving that it is the only import mechanism controlling the reduction in peak heat release rate in the investigated system for different irradiations. The flame retardancy performance is assessed comprehensively illuminating not only the strengths but also the weak points of the concepts. Guidelines for materials development are deduced and discussed. Apart from inorganic fillers (layered silicate, boehmite, etc.) not only carbon nanoobjects such as multiwall carbon nanotubes, multilayer graphene and graphene are investigated, but also nanoparticles that are more reactive and harbor the potential for more beneficial interactions with the polymer matrix.

  4. Nanotechnology finding its way into flame retardancy

    Science.gov (United States)

    Schartel, Bernhard

    2014-05-01

    Nanotechnology is one of the key technologies of the 21st century. The exploitation of "new" effects that arise from materials structured on the nano-scale has also been proposed successfully for flame retardancy of polymers since the end of the 90s. Of all of the approaches these include, at this time the use of nanocomposites offers the best potential for industrial application, also some other ideas are sketched, such as using electrospun nanofibers mats or layer-by-layer deposits as protection coatings, as well as sub-micrometer multilayer coatings as effective IR-mirrors. The general phenomena, inducing a flow limit in the pyrolysing melt and changing the fire residue, are identified in nanocomposites. Key experiments are performed such as quasi online investigation of the protection layer formation to understand what is going on in detail. The flame retardancy mechanisms are discussed and their impact on fire behaviour quantified. With the latter, the presentation pushes forward the state of the art. For instance, the heat shielding is experimentally quantified for a layered silicate epoxy resin nanocomposite proving that it is the only import mechanism controlling the reduction in peak heat release rate in the investigated system for different irradiations. The flame retardancy performance is assessed comprehensively illuminating not only the strengths but also the weak points of the concepts. Guidelines for materials development are deduced and discussed. Apart from inorganic fillers (layered silicate, boehmite, etc.) not only carbon nanoobjects such as multiwall carbon nanotubes, multilayer graphene and graphene are investigated, but also nanoparticles that are more reactive and harbor the potential for more beneficial interactions with the polymer matrix.

  5. Aspects of the mechanism of the flame ionization detector

    DEFF Research Database (Denmark)

    Holm, Torkil

    1999-01-01

    The development of flame ionization detection (FID) took place on an empirical basis without a clear understanding of the mechanism. The study of flames by MS showed that the all-important ion was the formylium ion CHO+. The pre-combustion degradation was thought to be a pyrolytic degradation...

  6. 49 CFR 195.438 - Smoking or open flames.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Smoking or open flames. 195.438 Section 195.438 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Operation and Maintenance § 195.438 Smoking or open flames. Each operator shall prohibit...

  7. 30 CFR 57.6904 - Smoking and open flames.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Smoking and open flames. 57.6904 Section 57.6904 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... General Requirements-Surface and Underground § 57.6904 Smoking and open flames. Smoking and use of...

  8. Buoyancy effects on the temperature field in downward spreading flames

    Science.gov (United States)

    Altenkirch, R. A.; Winchester, D. C.; Eichhorn, R.

    1982-01-01

    It is shown that flames which spread vertically down thermally thin fuels at the same Damkoehler number, and therefore have the same dimensionless spread rate, also have the same dimensionless temperature fields irrespective of differences in physical size. The Frey and Tien (1976) effects of pressure on flame size are due to the effects of pressure on the character of the induced buoyant flow.

  9. FIBRED MAGNESIUM HYDROXIDE AND FLAME-RESISTANT POLYENE MATERIAL

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The fibred mangesiun hydroxide from the bracite was treated with a surface active agent. The modified fibred magesium hydroxide as f lame-retardant,boric acid, barium stearate, polydimethyl siloxane fluid,vinyltr iethoxysilane as synergists of the flame-retardant were added to polyene resin. The flame-resistance polyene material prepared meets the requirements of EWCZ -6287-1.

  10. Measurement and Modeling of Particle Radiation in Coal Flames

    DEFF Research Database (Denmark)

    Bäckström, Daniel; Johansson, Robert; Andersson, Klas Jerker;

    2014-01-01

    properties. The in-flame particle radiation was measured with a Fourier transform infrared (FTIR) spectrometer connected to a water-cooled probe via fiber optics. In the cross-section of the flame investigated, the particles were found to be the dominating source of radiation. Apart from giving information...

  11. Flame retardant properties of triazine phosphonates derivative with cotton fabric

    Science.gov (United States)

    The flame retardant behavior of a cotton fabric treated with phosphorus-nitrogen containing triazine compound was evaluated. It was found that cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) is an excellent starting material for the preparation of phosphonates flame retardants that interacts wel...

  12. Soot Formation in Freely-Propagating Laminar Premixed Flames

    Science.gov (United States)

    Lin, K.-C.; Hassan, M. I.; Faeth, G. M.

    1997-01-01

    Soot formation within hydrocarbon-fueled flames is an important unresolved problem of combustion science. Thus, the present study is considering soot formation in freely-propagating laminar premixed flames, exploiting the microgravity environment to simplify measurements at the high-pressure conditions of interest for many practical applications. The findings of the investigation are relevant to reducing emissions of soot and continuum radiation from combustion processes, to improving terrestrial and spacecraft fire safety, and to developing methods of computational combustion, among others. Laminar premixed flames are attractive for studying soot formation because they are simple one-dimensional flows that are computationally tractable for detailed numerical simulations. Nevertheless, studying soot-containing burner-stabilized laminar premixed flames is problematical: spatial resolution and residence times are limited at the pressures of interest for practical applications, flame structure is sensitive to minor burner construction details so that experimental reproducibility is not very good, consistent burner behavior over the lengthy test programs needed to measure soot formation properties is hard to achieve, and burners have poor durability. Fortunately, many of these problems are mitigated for soot-containing, freely-propagating laminar premixed flames. The present investigation seeks to extend work in this laboratory for various soot processes in flames by observing soot formation in freely-propagating laminar premixed flames. Measurements are being made at both Normal Gravity (NG) and MicroGravity (MG), using a short-drop free-fall facility to provide MG conditions.

  13. Stationary premixed flames in spherical and cylindrical geometries

    Science.gov (United States)

    Ronney, P. D.; Whaling, K. N.; Abbud-Madrid, A.; Gatto, J. L.; Pisowiscz, V. L.

    1994-01-01

    Stationary source-free spherical flames ('flame balls') in premixed combustible gases were studied by employing low-gravity (micro-g) environments in a drop tower and an aircraft flying parabolic trajectories to diminish the impact of buoyancy-induced convective flow. Flame balls were found in all mixture families tested when: (1) the Lewis number Le of the deficient reactant was sufficiently low; and (2) the compositions were sufficiently close to the flammability limits. Probably as a consequence of the reduction in buoyant convection, the flammability limits at micro-g were significantly more dilute than those at Earth gravity; for example, 3.35% H2 vs 4.0% H2 in lean H2-air mixtures. By comparison with analytical and computational models, it is inferred that the phenomenon is probably related to diffusive-thermal effects in low-Le mixtures in conjunction with flame-front curvature and radiative heat losses from the combustion products. The chemical reaction mechanism appears to play no qualitative role. In the aircraft experiments, the gravity levels (approximately equal 10(exp -2)g(sub 0)) were found to cause noticeable motion of flame balls due to buoyancy, which in turn influenced the behavior of flame balls. At these g levels, a new type of transient, nearly cylindrical flame structure, termed 'flame strings,' was observed.

  14. The VLT-FLAMES Tarantula Survey

    OpenAIRE

    Taylor, W.D.; Evans, C J; Brott, I; Cantiello, M.; de Koter, A.; Mink, S.E. de; Langer, N.; N. R. Walborn

    2010-01-01

    The VLT-FLAMES Tarantula Survey is an ESO Large Programme that has provided multi-epoch spectroscopy of over 1000 stars in the 30 Doradus region in the Large Magellanic Cloud. Armed with this unique dataset the assembled consortium is now addressing a broad range of fundamental questions in both stellar and cluster evolution. Here we give an overview of the survey and the observational strategy, which was designed to be very sensitive to massive binaries. We highlight the power of the multi-e...

  15. Reverse-Engineering of the Cryptanalytic Attack Used in the Flame Super-Malware

    OpenAIRE

    Fillinger, Max; Stevens, Marc; Iwata, T; Cheon, J H

    2015-01-01

    In May 2012, a highly advanced malware for espionage dubbed Flame was found targeting the Middle-East. As it turned out, it used a forged signature to infect Windows machines by MITM-ing Windows Update. Using counter-cryptanalysis, Stevens found that the forged signature was made possible by a chosen-prefix attack on MD5 \\cite{DBLP:conf/crypto/Stevens13}. He uncovered some details that prove that this attack differs from collision attacks in the public literature, yet many questions about tec...

  16. Turbulent structure and dynamics of swirled, strongly pulsed jet diffusion flames

    KAUST Repository

    Liao, Ying-Hao

    2013-11-02

    The structure and dynamics of swirled, strongly pulsed, turbulent jet diffusion flames were examined experimentally in a co-flow swirl combustor. The dynamics of the large-scale flame structures, including variations in flame dimensions, the degree of turbulent flame puff interaction, and the turbulent flame puff celerity were determined from high-speed imaging of the luminous flame. All of the tests presented here were conducted with a fixed fuel injection velocity at a Reynolds number of 5000. The flame dimensions were generally found to be more impacted by swirl for the cases of longer injection time and faster co-flow flow rate. Flames with swirl exhibited a flame length up to 34% shorter compared to nonswirled flames. Both the turbulent flame puff separation and the flame puff celerity generally decreased when swirl was imposed. The decreased flame length, flame puff separation, and flame puff celerity are consistent with a greater momentum exchange between the flame and the surrounding co-flow, resulting from an increased rate of air entrainment due to swirl. Three scaling relations were developed to account for the impact of the injection time, the volumetric fuel-to-air flow rate ratio, and the jet-on fraction on the visible flame length. © 2013 Copyright Taylor and Francis Group, LLC.

  17. Field Effects of Buoyancy on a Premixed Turbulent Flame Studied by Particle Image Velocimetry

    Science.gov (United States)

    Cheng, Robert K.

    2003-01-01

    Typical laboratory flames for the scientific investigation of flame/turbulence interactions are prone to buoyancy effects. Buoyancy acts on these open flame systems and provides upstream feedbacks that control the global flame properties as well as local turbulence/flame interactions. Consequently the flame structures, stabilization limits, and turbulent reaction rates are directly or indirectly coupled with buoyancy. The objective of this study is to characterize the differences between premixed turbulent flames pointing upwards (1g), pointing downwards (-1g), and in microgravity (mg). The configuration is an inverted conical flame stabilized by a small cone-shaped bluff body that we call CLEAN Flames (Cone-Stabilized Lean Flames). We use two laser diagnostics to capture the velocity and scalar fields. Particle image velocimetry (PIV) measures the mean and root mean square velocities and planar imaging by the flame fronts method outlines the flame wrinkle topology. The results were obtained under typical conditions of small domestic heating systems such as water heaters, ovens, and furnaces. Significant differences between the 1g and -1g flames point to the need for including buoyancy contributions in theoretical and numerical calculations. In Earth gravity, there is a complex coupling of buoyancy with the turbulent flow and heat release in the flame. An investigation of buoyancy-free flames in microgravity will provide the key to discern gravity contributions. Data obtained in microgravity flames will provide the benchmark for interpreting and analyzing 1g and -1g flame results.

  18. Transient behaviors of a flame over a Tsuji burner

    Institute of Scientific and Technical Information of China (English)

    Young-Da Chen; Da-Da Chen; Chiun-Hsun Chen

    2008-01-01

    The present study investigated numerically the physical mechanisms underlying the transient behaviors of the flame over a porous cylindrical burner. The numerical results showed that a cold flow structure at a fixed inflow velocity of Uin = 0.6 m/s in a wind tunnel could be observed in two co-existing recirculation flows. Flow variations occur repeatedly until t = 4.71 s, and then a vortex existed steadily behind the burner and no shading occurred. The ignition of flammable mixture led to a rapid rise in gas temperature and a sudden gas expansion. When it reached the stable envelope flame condition, Uin is adjusted to an assigned value. Two blow-off mechanisms were identified. It was also found in the study flame shapes with buoyancy effects agreed with the ones observed experimentally by Tsai. Furthermore, the lift-off flame would appear briefly between the envelopes and wake ones, and was stabilized as a wake flame.

  19. Premixed double concentric jets flame with swirl flow

    Energy Technology Data Exchange (ETDEWEB)

    Ito, K.; Song, K.

    1987-01-01

    Swirl flow has been commonly used for stabilization of the high-intensity combustion process. The swirl flow is imparted to the secondary airflow by the swirl vane. Flame stability limits, flame shapes, the concentration of combustion gas, and the temperature distribution in the recirculation zone were measured, and high-speed schlieren photographs were taken. The results indicate that flame stability limits decrease with increasing swirl number in weak swirls because the mixture deteriorates due to the swirl in the recirculation zone. But an increase with increasing swirl number in strong swirls is seen in the mixing ratio, which is promoted by the swirl. For no swirl or weak swirls, a recirculation zone formed behind the burner rim affects the flame stability. When there is a strong swirl, a recirculation zone formed by the swirl affects the flame stability. 9 references.

  20. Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames

    International Nuclear Information System (INIS)

    We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (−g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in −g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in −g flames, which reduces the time to gel for nanoparticles by ≈106 s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale.

  1. Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames

    Energy Technology Data Exchange (ETDEWEB)

    Chakrabarty, Rajan K., E-mail: rajan.chakrabarty@gmail.com [Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130 (United States); Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Novosselov, Igor V. [Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States); Enertechnix Inc., Maple Valley, Washington 98068 (United States); Beres, Nicholas D.; Moosmüller, Hans [Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Sorensen, Christopher M. [Condensed Matter Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States); Stipe, Christopher B. [TSI Incorporated, 500 Cardigan Rd, Shoreview, Minnesota 55126 (United States)

    2014-06-16

    We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (−g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in −g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in −g flames, which reduces the time to gel for nanoparticles by ≈10{sup 6} s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale.

  2. Experimental Measurements of Two-dimensional Planar Propagating Edge Flames

    Science.gov (United States)

    Villa-Gonzalez, Marcos; Marchese, Anthony J.; Easton, John W.; Miller, Fletcher J.

    2007-01-01

    The study of edge flames has received increased attention in recent years. This work reports the results of a recent study into two-dimensional, planar, propagating edge flames that are remote from solid surfaces (called here, free-layer flames, as opposed to layered flames along floors or ceilings). They represent an ideal case of a flame propagating down a flammable plume, or through a flammable layer in microgravity. The results were generated using a new apparatus in which a thin stream of gaseous fuel is injected into a low-speed laminar wind tunnel thereby forming a flammable layer along the centerline. An airfoil-shaped fuel dispenser downstream of the duct inlet issues ethane from a slot in the trailing edge. The air and ethane mix due to mass diffusion while flowing up towards the duct exit, forming a flammable layer with a steep lateral fuel concentration gradient and smaller axial fuel concentration gradient. We characterized the flow and fuel concentration fields in the duct using hot wire anemometer scans, flow visualization using smoke traces, and non-reacting, numerical modeling using COSMOSFloWorks. In the experiment, a hot wire near the exit ignites the ethane air layer, with the flame propagating downwards towards the fuel source. Reported here are tests with the air inlet velocity of 25 cm/s and ethane flows of 967-1299 sccm, which gave conditions ranging from lean to rich along the centerline. In these conditions the flame spreads at a constant rate faster than the laminar burning rate for a premixed ethane air mixture. The flame spread rate increases with increasing transverse fuel gradient (obtained by increasing the fuel flow rate), but appears to reach a maximum. The flow field shows little effect due to the flame approach near the igniter, but shows significant effect, including flow reversal, well ahead of the flame as it approaches the airfoil fuel source.

  3. Blue nano titania made in diffusion flames.

    Science.gov (United States)

    Teleki, Alexandra; Pratsinis, Sotiris E

    2009-05-21

    Blue titanium suboxide nanoparticles (including Magneli phases) were formed directly without any post-processing or addition of dopants by combustion of titanium-tetra-isopropoxide (TTIP) vapor at atmospheric pressure. Particle size, phase composition, rutile and anatase crystal sizes as well as the blue coloration were controlled by rapid quenching of the flame with a critical flow nozzle placed at various heights above the burner. The particles showed a broad absorption in the near-infrared region and retained their blue color upon storage in ambient atmosphere. A high concentration of paramagnetic Ti3+ centres was found in the substoichiometric particles by electron paramagnetic resonance (EPR) spectroscopy. Furthermore particles with controlled band gap energy from 3.2 to 3.6 eV were made by controlling the burner-nozzle-distance from 10 to 1 cm, respectively. The color robustness and extent of suboxidation could be further enhanced by co-oxidation of TTIP with hexamethyldisiloxane in the flame resulting in SiO2-coated titanium suboxide particles. The process is cost-effective and green while the particles produced can replace traditional blue colored, cobalt-containing pigments. PMID:19421486

  4. A retrospective quality of life analysis using the lung cancer symptom scale in patients treated with palliative radiotherapy for advanced nonsmall cell lung cancer

    International Nuclear Information System (INIS)

    Purpose: To measure symptom palliation in patients treated with radiation therapy for advanced nonsmall cell lung cancer (NSCLC). Methods and Materials: Five hundred thirty patients with NSCLC were treated at the Medical College of Virginia between 1988 and 1993. Sixty-three patients with the least favorable prognostic features received palliative radiation to 30 Gy in 10 or 12 fractions for symptoms related to the presence of intrathoracic tumor. The observer portion of the Lung Cancer Symptom Scale (LCSS) was employed in a retrospective chart review, scoring measures of appetite, fatigue, cough, dyspnea, hemoptysis, and pain. Results: In 54 evaluable patients, median survival was 4 months and was independent of age, stage, performance status, or histology. Ninety-six percent of the patients had at least one LCSS symptom at presentation. Fatigue was unaffected by therapy. Improvements in appetite (p = 0.68) and pain (p = 0.61) were not statistically significant. There was, however, a statistically significant reduction in cough (p = 0.01), hemoptysis (p = 0.001), and dyspnea (p 0.0003). Self-limiting acute side effects included transient esophagitis in 37% of patients, though no severe toxicities were noted. Conclusions: These results suggest symptomatic benefit from radiotherapy even in those NSCLC patients with advanced disease and a limited life expectancy. Treatment should be given to patients whose symptoms are most amenable to palliation. A site-specific quality of life instrument such as the LCSS should be included within any future clinical trial of NSCLC management so that symptom control may be scored as a treatment outcome in addition to disease-free survival

  5. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    Energy Technology Data Exchange (ETDEWEB)

    T. Scott Hickman; James J. Justice

    2002-01-09

    The OXY-operated Class 2 Project at West Welch is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO{sub 2} injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO{sub 2} flood design based on the reservoir characterization. Although Budget Period 1 for the Project officially ended 12/31/96, reservoir characterization and simulation work continued during the Budget Period 2. During the fifth and sixth annual reporting periods (8/3/98-8/2/00) covered by this report, work continued on interpretation of the cross well seismic data to create porosity and permeability profiles which were distributed into the reservoir geostatistically. The initial interwell seismic CO{sub 2} monitor survey was conducted, the acquired data processed and interpretation started. Only limited well work and facility construction was conducted in the project area. The CO{sub 2} injection initiated in October 1997 was continued, although the operator had to modify the operating plan in response to low injection rates, well performance and changes in CO{sub 2} supply. CO{sub 2} injection was focused in a smaller area to increase the reservoir processing rate. By the end of the reporting period three producers had shown sustained oil rate increases and ten wells had experienced gas (CO{sub 2}) breakthrough.

  6. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    Energy Technology Data Exchange (ETDEWEB)

    Tom Beebe

    2003-05-05

    The OXY-operated Class 2 Project at West Welch is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO{sub 2} injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO{sub 2} flood design based on the reservoir characterization. Although Budget Period 1 for the Project officially ended 12/31/96, reservoir characterization and simulation work continued during the Budget Period 2. During the seventh annual reporting period (8/3/00-8/2/01) covered by this report, work continued on interpretation of the interwell seismic data to create porosity and permeability profiles which were distributed into the reservoir geostatistically. The initial interwell seismic CO{sub 2} monitor survey was conducted and the acquired data processed and interpretation started. Only limited well work and facility construction were conducted in the project area. The CO{sub 2} injection initiated in October 1997 was continued, although the operator had to modify the operating plan in response to low injection rates, well performance and changes in CO{sub 2} supply. CO{sub 2} injection was focused in a smaller area to increase the reservoir processing rate. By the end of the reporting period three producers had shown sustained oil rate increases and six wells had experienced gas (CO{sub 2}) breakthrough.

  7. Effect of vorticity flip-over on the premixed flame structure: First experimental observation of type I inflection flames

    CERN Document Server

    El-Rabii, Hazem

    2015-01-01

    Premixed flames propagating in horizontal tubes are observed to take on shape convex towards the fresh mixture, which is commonly explained as a buoyancy effect. A recent rigorous analysis has shown, on the contrary, that this process is driven by the balance of vorticity generated by a curved flame front with the baroclinic vorticity, and predicted existence of a regime in which the leading edge of the flame front is concave. We report first experimental realization of this regime. Our experiments on ethane and n-butane mixtures with air show that flames with an inflection point on the front are regularly produced in lean mixtures, provided that a sufficiently weak ignition is used. The observed flame shape perfectly agrees with the theoretically predicted.

  8. Effect of vorticity flip-over on the premixed flame structure: Experimental observation of type-I inflection flames.

    Science.gov (United States)

    El-Rabii, Hazem; Kazakov, Kirill A

    2015-12-01

    Premixed flames propagating in horizontal tubes are observed to take on a convex shape towards the fresh mixture, which is commonly explained as a buoyancy effect. A recent rigorous analysis has shown, on the contrary, that this process is driven by the balance of vorticity generated by a curved flame front with the baroclinic vorticity, and predicted existence of a regime in which the leading edge of the flame front is concave. We report experimental realization of this regime. Our experiments on ethane and n-butane mixtures with air show that flames with an inflection point on the front are regularly produced in lean mixtures, provided that a sufficiently weak ignition is used. The observed flame shape perfectly agrees with that theoretically predicted. PMID:26764801

  9. Development of a flaming machine for the disinfection of poultry grow-out facilities

    Directory of Open Access Journals (Sweden)

    Michele Raffaelli

    2013-06-01

    Full Text Available Chemical treatments are commonly adopted for poultry house sanitation. In fact, ordinary floor disinfection is needed to deplete the pathogenic population (i.e. various species of bacteria and fungi and reduce the risk of meat contamination. The increasing focus on the health of consumers and operators, as well as on food quality, has led farmers to consider alternative environmentally friendly methods. Research was carried out to set up a new machine for floor disinfection of poultry houses by open flame. The trials were run in controlled conditions in the laboratory of the University of Pisa, Italy, and on a private farm. The first experiment consisted of a series of test bench trials carried out to evaluate the efficacy and the adjustment of liquefied petroleum gas (LPG-fed open flame burners on pre-inoculated steel plates. In the second experiment, the operative parameters of a custom-built 1.5 m wide mounted flaming machine were determined and the biological effects of the treatment were compared to ordinary chemical treatments. The results obtained were very promising. Test bench trials showed a 4-log reduction in E. coli, and microbial determinations carried out on-farm did not show any difference between thermal and chemical treatment. In addition, the cost estimation showed that thermal disinfection is approximately 4-fold cheaper than chemical sanitation methods. The effective working capacity of the machine was approximately 1700 m2 h–1, and the LPG consumption was approximately 16 kg per 1000 m2. Flame disinfection of poultry grow-out facilities could represent a valid alternative to chemical disinfection.

  10. Numerical Simulation of Microgravity Flame Spread Over Solid Combustibles

    Institute of Scientific and Technical Information of China (English)

    JIANGXi; FANWeicheng

    1995-01-01

    A computational model of three-dimensional,time-dependent flame spread in microgravity environment is presented.THe solid is assumed to be a thermally-thin,pyrolysing cellulosic sheet.The gas phase model includes the full Navier-Stokes equations with density and pressure variations and six-flus model of radiation heat transfer,The solid phase model consists of continuity and energy equations whose solution provides boundary conditions for the gas phase equatons.In the numerical procedure,the gas-and solid -phase equations are solved separately and iteratively at each time step.Predictions have been made of flame spreas in slow forced flow under gravitational acceleration normal to fuel surface and flame spread in a quiescent environment in an enclosed chamber under gravitational acceleration parallel to fuel surface.Numerical simulations show that,under microgravity,slow-flow conditions,flame spread process is highly unsteady with the upstream flame spreads faster than the downstream flame after a period of ignition,It has also been shown that the level of microgravity has a significant effect on the flame spread process.

  11. Streamline segment statistics of premixed flames with nonunity Lewis numbers

    Science.gov (United States)

    Chakraborty, Nilanjan; Wang, Lipo; Klein, Markus

    2014-03-01

    The interaction of flame and surrounding fluid motion is of central importance in the fundamental understanding of turbulent combustion. It is demonstrated here that this interaction can be represented using streamline segment analysis, which was previously applied in nonreactive turbulence. The present work focuses on the effects of the global Lewis number (Le) on streamline segment statistics in premixed flames in the thin-reaction-zones regime. A direct numerical simulation database of freely propagating thin-reaction-zones regime flames with Le ranging from 0.34 to 1.2 is used to demonstrate that Le has significant influences on the characteristic features of the streamline segment, such as the curve length, the difference in the velocity magnitude at two extremal points, and their correlations with the local flame curvature. The strengthenings of the dilatation rate, flame normal acceleration, and flame-generated turbulence with decreasing Le are principally responsible for these observed effects. An expression for the probability density function (pdf) of the streamline segment length, originally developed for nonreacting turbulent flows, captures the qualitative behavior for turbulent premixed flames in the thin-reaction-zones regime for a wide range of Le values. The joint pdfs between the streamline length and the difference in the velocity magnitude at two extremal points for both unweighted and density-weighted velocity vectors are analyzed and compared. Detailed explanations are provided for the observed differences in the topological behaviors of the streamline segment in response to the global Le.

  12. Buoyancy Effects in Fully-Modulated, Turbulent Diffusion Flames

    Science.gov (United States)

    Hermanson, J. C.; Johari, H.; Ghaem-Maghami, E.; Stocker, D. P.; Hegde, U. G.; Page, K. L.

    2003-01-01

    Pulsed combustion appears to have the potential to provide for rapid fuel/air mixing, compact and economical combustors, and reduced exhaust emissions. The objective of this experiment (PuFF, for Pulsed-Fully Flames) is to increase the fundamental understanding of the fuel/air mixing and combustion behavior of pulsed, turbulent diffusion flames by conducting experiments in microgravity. In this research the fuel jet is fully-modulated (i.e., completely shut off between pulses) by an externally controlled valve system. This gives rise to drastic modification of the combustion and flow characteristics of flames, leading to enhanced fuel/air mixing compared to acoustically excited or partially-modulated jets. Normal-gravity experiments suggest that the fully-modulated technique also has the potential for producing turbulent jet flames significantly more compact than steady flames with no increase in exhaust emissions. The technique also simplifies the combustion process by avoiding the acoustic forcing generally present in pulsed combustors. Fundamental issues addressed in this experiment include the impact of buoyancy on the structure and flame length, temperatures, radiation, and emissions of fully-modulated flames.

  13. Buoyancy Effects upon Vapor Flame and Explosion Processes

    Science.gov (United States)

    Edelman, R. B.; Harsha, P. T.

    1985-01-01

    The objective of this microgravity project is to develop an experimental and theoretical analyses critical to the understanding of the coupling of buoyancy and turbulence generation and its effect on fuel-air mixing, flame intensity and flame propagation in jet diffusion flames. The experiment is designed to examine certain effects of buoyancy acting on a diffusion flame in which the flame is directed either upward or downward. This change from negative to positive g is observed to significantly alter the flame shape although all other operating conditions are the same for both configurations. However, to perform this experiment a significant coaxial secondary air flow is needed in order to prevent flow reversal when the flame is inverted. The theoretical analysis that has been developed handles the secondary air flow and the extreme change in gravity vector direction. Thus the data will provide a measure of credibility of the analysis which will then be used to assist in the design of the actual zero-g experiment.

  14. Calculations and surface quality measurements of high-asymmetry angle x-ray crystal monochromators for advanced x-ray imaging and metrological applications

    Science.gov (United States)

    Zápražný, Zdenko; Korytár, Dušan; Jergel, Matej; Šiffalovič, Peter; Dobročka, Edmund; Vagovič, Patrik; Ferrari, Claudio; Mikulík, Petr; Demydenko, Maksym; Mikloška, Marek

    2015-03-01

    We present the numerical optimization and the technological development progress of x-ray optics based on asymmetric germanium crystals. We show the results of several basic calculations of diffraction properties of germanium x-ray crystal monochromators and of an analyzer-based imaging method for various asymmetry factors using an x-ray energy range from 8 to 20 keV. The important parameter of highly asymmetric monochromators as image magnifiers or compressors is the crystal surface quality. We have applied several crystal surface finishing methods, including advanced nanomachining using single-point diamond turning (SPDT), conventional mechanical lapping, chemical polishing, and chemomechanical polishing, and we have evaluated these methods by means of atomic force microscopy, diffractometry, reciprocal space mapping, and others. Our goal is to exclude the chemical etching methods as the final processing technique because it causes surface undulations. The aim is to implement very precise deterministic methods with a control of surface roughness down to 0.1 nm. The smallest roughness (˜0.3 nm), best planarity, and absence of the subsurface damage were observed for the sample which was machined using an SPDT with a feed rate of 1 mm/min and was consequently polished using a fine polishing 15-min process with a solution containing SiO2 nanoparticles (20 nm).

  15. 美国管道质量检验标准先进性研究%The Advancement Research on American Pipeline Quality Supervision Standards

    Institute of Scientific and Technical Information of China (English)

    费雪松; 蔡亮; 侯金山; 李青春; 刘凤侠

    2015-01-01

    The high efficiency and safe supervision work was important for guarantee new pipeline quality and pipeline safe operation. PetroChina West-Eest Gas Pipeline Company successfully explored the application of American supervision company, and the good result was achieved. The idea of referring American pipeline supervision standard to improve domestic standard was raised. The paper introduced API RP 1169-2013《Recommended Practice for Basic Inspection Requirements-New Pipeline Construction》, with the difference between American and China new pipeline quality inspection was studied in detail. The advancement of API RP 1169-2013 were expounded, including the detailed profession classification of inspector, and as a representative of pipeline operator with the highest voice right, and strict and detailed pipeline constructionfield safe supervision measure, and the perfect pipeline construction quality inspection requirement. Finally, the suggestion of adopting API RP 1169-2013 was made based on the situation of domestic pipeline construction standard and supervision standard.%实施安全高效监理工作,对于保障新建管道质量和管道安全运行至关重要。西气东输管道探索应用了美国监理公司的做法,取得了良好效果。本文提出了借鉴美国管道监理标准改进国内监理工作的理念,以API RP 1169《新建管道工程基本检验要求推荐做法》为例,深入研究了中美新建管道质量检验的差异。该标准的先进性表现在检验员专业化分细致、检验员代表运营方利益且拥有最高话语权、管道施工现场安全监护措施严格细致,管道施工质量检验要求完善等。最后,基于国内管道施工和监理标准现状,提出了API RP 1169采标建议。

  16. The VLT-FLAMES Tarantula Survey. XIV. The O-type stellar content of 30 Doradus

    OpenAIRE

    N. R. Walborn; Sana, H.; Simón-Díaz, S.; Maíz Apellániz, J; Taylor, W.D.; Evans, C J; Markova, N.; Lennon, D.J.; Koter, de, A.

    2014-01-01

    Detailed spectral classifications are presented for 352 O-B0 stars in the VLT-FLAMES Tarantula Survey ESO Large Programme, of which 213 O-type are judged of sufficiently high quality for further morphological analysis. Among them, six subcategories of special interest are distinguished. (1) Several new examples of the earliest spectral types O2-O3 have been found, while a previously known example has been determined to belong to the nitrogen-rich ON2 class. (2) A group of extremely rapidly ro...

  17. Similarity solutions in buoyancy-controlled turbulent diffusion flame modeling; Turbulent buoyant diffusion flame modeling

    Energy Technology Data Exchange (ETDEWEB)

    Pivovarov, M.A.; Zhang, H.; Ramakev, D.E.; Tatem, P.A.; Williams, F.W. (George Washington Univ., Washington, DC (United States). Dept. of Chemistry)

    1993-02-01

    This paper considers the applicability of different versions of the k-[epsilon] hypothesis of turbulence for flame modeling. Utilizing similarity solutions, the authors find that the k-[epsilon] hypothesis gives a finite radius for a weak axisymmetric plume above the heat source. The radius of this plume is defined as an eigenvalue of the boundary value problem with unknown boundary. Solving this problem with an adjusted set of parameters from the standard version of the k-[epsilon] hypothesis gives excellent agreement with experimental data for center line and radial profiles of the mean and turbulent quantities, and also for the radius of the plume and entrainment level. In contrast, the standard set of parameters, widely utilized in flame modeling, gives inaccurate predictions. Specifically, this set of parameters yields underestimates of the radius of the plume and the entrainment level. Since this same trend has been extensively observed in flame modeling, the authors conclude that the standard set of parameters for the k-[epsilon] hypothesis is inadequate, and that this is the main reason for the shortcomings of previous numerical models.

  18. Flame retardant cotton fabrics treated with organophosphorus polymer.

    Science.gov (United States)

    Abou-Okeil, A; El-Sawy, S M; Abdel-Mohdy, F A

    2013-02-15

    Organo-phosphorus compounds was prepared and applied onto cotton fabrics as flame retarding agent. methacryloloxyethylorthophoshor tetraethyl diamidate (MPD) was prepared and its structure was confirmed by IR, NMR and mass spectroscopy. Pyrovatex as commercial flame retardant was used for comparative study. Impregnation method was used as coating for the application of the organophosphorus compounds to cotton fabrics. The major factors affecting the reaction were studied. The results show that the prepared organophosphorus compound can be successfully used as flame retardant for cotton fabrics. PMID:23399290

  19. Case study: flame arresters and exploding gasoline containers.

    Science.gov (United States)

    Hasselbring, Lori C

    2006-03-17

    This paper describes the case study of a portable plastic gasoline container explosion and fire. While working at home on a science project to determine the burn rates of different types of wood fuel, a 14-year-old boy was severely burned after flames traveled back up into the portable gasoline container and exploded. A witness heard the explosion and reports that the flames went perhaps 10 ft in the air. It is shown by experimentation that a flame arrester installed in the pour opening of the portable gasoline container would have prevented an explosion inside the gasoline container.

  20. Flame spectra of solid propellants during unstable combustion.

    Science.gov (United States)

    Eisel, J. L.; Ryan, N. W.; Baer, A. D.

    1972-01-01

    The spectral and temporal details of the flames of a series of ammonium perchlorate-polyurethane propellants during both unstable and stable combustion were observed experimentally. A 400-scan per second optical spectrometer operating in the middle infrared region was used. During unstable combustion at low ratios of chamber free volume to nozzle throat area, three different frequencies were observed simultaneously. These were attributable to at least two mechanisms. During stable combustion periodic fluctuations in flame temperature and composition were also observed. Some aspects of theory of bulk mode instability were confirmed, but the assumptions of constant flame temperature and constant composition were found to be inaccurate.

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

    Directory of Open Access Journals (Sweden)

    Xiaodan Zhu

    2014-01-01

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

  2. Numerical study of transient evolution of lifted jet flames: partially premixed flame propagation and influence of physical dimensions

    Science.gov (United States)

    Chen, Zhi; Ruan, Shaohong; Swaminathan, Nedunchezhian

    2016-07-01

    Three-dimensional (3D) unsteady Reynolds-averaged Navier-Stokes simulations of a spark-ignited turbulent methane/air jet flame evolving from ignition to stabilisation are conducted for different jet velocities. A partially premixed combustion model is used involving a correlated joint probability density function and both premixed and non-premixed combustion mode contributions. The 3D simulation results for the temporal evolution of the flame's leading edge are compared with previous two-dimensional (2D) results and experimental data. The comparison shows that the final stabilised flame lift-off height is well predicted by both 2D and 3D computations. However, the transient evolution of the flame's leading edge computed from 3D simulation agrees reasonably well with experiment, whereas evident discrepancies were found in the previous 2D study. This difference suggests that the third physical dimension plays an important role during the flame transient evolution process. The flame brush's leading edge displacement speed resulting from reaction, normal and tangential diffusion processes are studied at different typical stages after ignition in order to understand the effect of the third physical dimension further. Substantial differences are found for the reaction and normal diffusion components between 2D and 3D simulations especially in the initial propagation stage. The evolution of reaction progress variable scalar gradients and its interaction with the flow and mixing field in the 3D physical space have an important effect on the flame's leading edge propagation.

  3. Some new experimental photonic flame effect features

    CERN Document Server

    Tcherniega, N V

    2007-01-01

    The results of the spectral, energetical and temporal characteristics of radiation in the presence of the photonic flame effect are presented. Artificial opal posed on Cu plate at the temperature of liquid nitrogen boiling point (77 K) being irradiated by nanosecond ruby laser pulse produces long- term luminiscence with a duration till ten seconds with a finely structured spectrum in the the antistocks part of the spectrum. Analogous visible luminescence manifesting time delay appeared in other samples of the artificial opals posed on the same plate. In the case of the opal infiltrated with different nonlinear liquids the threshold of the luminiscence is reduced and the spatial disribution of the bright emmiting area on the opal surface is being changed. In the case of the putting the frozen nonlinear liquids on the Cu plate long-term blue bright luminiscence took place in the frozen species of the liquids. Temporal characteristics of this luminiscence are nearly the same as in opal matrixes.

  4. Analysis of polydisperse fuel spray flame

    Science.gov (United States)

    Nave, Ophir; Lehavi, Yaron; Ajadi, Suraju; Gol'dshtein, Vladimir

    2016-06-01

    In this paper we analyzed the model of polydisperse fuel spray flame by using the sectional approach to describe the droplet-droplet interaction within the spray. The radii of the droplets are described by a probability density function. Our numerical simulations include a comparative analysis between three empirical droplet size distributions: the Rosin-Rammler distribution, the log-normal distribution and the Nakiyama-Tanasawa distribution. The log-normal distribution was found to produce a reasonable approximation to both the number and volume size distribution function. In addition our comparative analysis includes the application of the homotopy analysis method which yields convergent solutions for all values of the relevant parameters. We compared the above results to experimental fuel spray data such as {{Tetralin}} , n-{{Decane}} , and n-{{Heptane}} .

  5. [Flame temperature distribution measurement of solid propellants].

    Science.gov (United States)

    Zhao, Wen-hua; Zhu, Shu-guang; Li, Yan; Fang, Zhong-yan; Yang, Rong-jie; Li, Yu-ping; Zhang, Jie; Liu, Yun-fei

    2004-09-01

    Many high temperature bodies such as flame, in which chemical reactions are very complex, emit their own spectra. These emission spectra usually consist of the spectral lines, spectral bands and the continuous spectra. In some cases, the spectral lines gather together. It is very difficult to find the right single spectral line when the spectral line intensity method is used. To deal with this problem, the idea that the single spectral line intensity is replaced by the total intensity of many spectral lines to measure the temperature is mentioned. And the relative intensity method is also changed to deal with this idea. The measurement of the temperature distribution based on this improved method is successful, and the measurement results are compared with the results of the thermocouple method.

  6. Augmenting the Structures in a Swirling Flame via Diffusive Injection

    Directory of Open Access Journals (Sweden)

    Jonathan Lewis

    2014-01-01

    Full Text Available Small scale experimentation using particle image velocimetry investigated the effect of the diffusive injection of methane, air, and carbon dioxide on the coherent structures in a swirling flame. The interaction between the high momentum flow region (HMFR and central recirculation zone (CRZ of the flame is a potential cause of combustion induced vortex breakdown (CIVB and occurs when the HMFR squeezes the CRZ, resulting in upstream propagation. The diffusive introduction of methane or carbon dioxide through a central injector increased the size and velocity of the CRZ relative to the HMFR whilst maintaining flame stability, reducing the likelihood of CIVB occurring. The diffusive injection of air had an opposing effect, reducing the size and velocity of the CRZ prior to eradicating it completely. This would also prevent combustion induced vortex breakdown CIVB occurring as a CRZ is fundamental to the process; however, without recirculation it would create an inherently unstable flame.

  7. Chaotic map models of soot fluctuations in turbulent diffusion flames

    Energy Technology Data Exchange (ETDEWEB)

    Mukerji, S.; McDonough, J.M.; Menguec, M.P.; Manickavasagam, S. [Univ. of Kentucky, Lexington, KY (United States). Dept. of Mechanical Engineering; Chung, S. [Univ. of Illinois, Urbana, IL (United States). Dept. of Chemical Engineering

    1998-10-01

    In this paper, the authors introduce a methodology to characterize time-dependent soot volume fraction fluctuations in turbulent diffusion flames via chaotic maps. The approach is based on the hypothesis that fluctuations of properties in turbulent flames are deterministic in nature, rather than statistical. The objective is to develop models of these fluctuations to be used in comprehensive algorithms to study the nature of turbulent flames and the interaction of turbulence with radiation. To this end the authors measured the time series of soot scattering coefficient in an ethylene diffusion flame from light scattering experiments and fit these data to linear combinations of chaotic maps of the unit interval. Both time series and power spectra can be modeled with reasonable accuracy in this way.

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

    Directory of Open Access Journals (Sweden)

    Li Chen

    2010-10-01

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

  9. Probing flame chemistry with MBMS, theory, and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Westmoreland, P.R. [Univ. of Massachusetts, Amherst (United States)

    1993-12-01

    The objective is to establish kinetics of combustion and molecular-weight growth in C{sub 3} hydrocarbon flames as part of an ongoing study of flame chemistry. Specific reactions being studied are (1) the growth reactions of C{sub 3}H{sub 5} and C{sub 3}H{sub 3} with themselves and with unsaturated hydrocarbons and (2) the oxidation reactions of O and OH with C{sub 3}`s. This approach combines molecular-beam mass spectrometry (MBMS) experiments on low-pressure flat flames; theoretical predictions of rate constants by thermochemical kinetics, Bimolecular Quantum-RRK, RRKM, and master-equation theory; and whole-flame modeling using full mechanisms of elementary reactions.

  10. Development of Flame Retardants for Engineering Polymers and Polyurethanes

    Science.gov (United States)

    Desikan, Anantha

    2013-03-01

    With a broad portfolio of brominated, organophosphorus and inorganic flame retardants, ICL Industrial Products (ICL-IP) is engaged in the development of new flame retardants by exploiting the synergism between bromine based, phosphorus based and other halogen-free flame retardants. ICL-IP is also focusing on the development of polymeric and reactive flame retardants. This presentation will give examples of existing and new polymeric and reactive products for applications in thermoplastics, thermosets and polyurethane foam. This presentation will also show examples of phosphorus-bromine synergism allowing partial or complete elimination of antimony trioxide in many thermoplastics for electronic applications. New synergistic combinations of magnesium hydroxide with phosphorus and other halogen-free FRs will be presented. Work done in collaboration with S. Levchik, ICL-IP America, 430 Saw Mill Rriver Rd., Ardsley, NY, 10502, USA and M. Leifer, ICL-IP, P. O. Box 180, Beer Sheva 84101, Israel.

  11. THERMAL DEGRADATION AND FLAME RETARDANCY OF CALCIUM ALGINATE FIBERS

    Institute of Scientific and Technical Information of China (English)

    Qing-shan Kong; Bing-bing Wang; Quan Ji; Yan-zhi Xia; Zhao-xia Guo; Jian Yu

    2009-01-01

    Calcium alginate fibers were prepared by wet spinning of sodium alginate into a coagulating bath containing calcium chloride. The thermal degradation and flame retardancy of calcium alginate fibers were investigated with thermal gravimetry (TG), X-ray diffraction (XRD), limiting oxygen index (LOI) and cone calorimeter (CONE). The results show that calcium alginate fibers are inherently flame retardant with a LOI value of 34, and the heat release rate (HRR), total heat release (THR), CO and CO_2 concentrations during combustion are much lower compared with those of viscose fibers. Calcium carbonate and calcium oxide were formed during thermal degradation of calcium alginate fibers at different temperatures. The shape of calcium alginate fibers is well kept after LOI test. The rigid combustion residue char acts as an effective barrier to the outward diffusion of flame and heat. The combustion process and flame retardant mechanism of calcium alginate fibers are also discussed.

  12. Persistence, bioaccumulation and toxicity of halogen-free flame retardants.

    NARCIS (Netherlands)

    S.L. Waaijers; D Kong; H.S. Hendriks; C.A. de Wit; I.T. Cousins; R.H.S. Westerink; P.E.G. Leonards; M.H.S. Kraak; W. Admiraal; P. de Voogt; J.R. Parsons

    2012-01-01

    Polymers are synthetic organic materials that have a high carbon and hydrogen content, which renders them readily combustible. When used in buildings, electrical appliances, furniture, textiles, transportation, mining, and in many other applications, polymers have to fulfill flame retardancy regulat

  13. A Kinetic Model of Chromium in a Flame

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Chromium has been identified as a carcinogenic metal.Incineration is the useful method for disposal of toxic chromium hazard waste and a chromium kinetic model in a flame is very important to study chromium oxidation.Chromium chemical kinetics over a range of temperatures of a hydrogen/air flame is proposed.Nine chromium compounds and fifty-eight reversible chemical reactions were considered The forward reaction rates are calculated based on the molecular collision approach for unknown ones and Arrhenius's Law for known ones.The backward reaction rates were calculated according to forward reaction rates, the equilibrium constants and chemical thermodynamics.It is verified by several equilibrium cases and is tested by a hydrogen/air diffusion flame.The results show that the kinetic model could be used in cases in which the chromium kinetics play an important role in a flame

  14. STUDY ON STRUCTURE OF SINGULAR POINTS OF LAMINAR FLAME SYSTEM

    Institute of Scientific and Technical Information of China (English)

    WANG Xiu-e; YIN Xian-jun

    2005-01-01

    Under some certain assumptions, the physical model of the air combustion system was simplified to a laminar flame system. The mathematical model of the laminar flame system, which was built according to thermodynamics theory and the corresponding conservative laws, was studied. With the aid of qualitative theory and method of ordinary differential equations, the location of singular points on the Rayleigh curves is determined,the qualitative structure and the stability of the singular points of the laminar flame system,which are located in the areas of deflagration and detonation, are given for different parameter values and uses of combustion. The phase portraits of the laminar flame system in the reaction-stagnation enthalpy and combustion velocity-stagnation enthalpy planes are shown in the corresponding figures.

  15. Effects on quality of life of weekly docetaxel-based chemotherapy in patients with locally advanced or metastatic breast cancer: results of a single-centre randomized phase 3 trial

    Directory of Open Access Journals (Sweden)

    Rinaldo Massimo

    2011-02-01

    Full Text Available Abstract Background To evaluate whether weekly schedules of docetaxel-based chemotherapy were superior to 3-weekly ones in terms of quality of life in locally advanced or metastatic breast cancer. Methods Patients with locally advanced or metastatic breast cancer, aged ≤ 70 years, performance status 0-2, chemotherapy-naive for metastatic disease, were eligible. They were randomized to weekly or 3-weekly combination of docetaxel and epirubicin, if they were not treated with adjuvant anthracyclines, or docetaxel and capecitabine, if treated with adjuvant anthracyclines. Primary end-point was global quality of life change at 6-weeks, measured by EORTC QLQ-C30. With two-sided alpha 0.05 and 80% power for 35% effect size, 130 patients per arm were needed. Results From February 2004 to March 2008, 139 patients were randomized, 70 to weekly and 69 to 3-weekly arm; 129 and 89 patients filled baseline and 6-week questionnaires, respectively. Global quality of life was better in the 3-weekly arm (p = 0.03; patients treated with weekly schedules presented a significantly worsening in role functioning and financial scores (p = 0.02 and p Conclusions In this trial, the weekly schedules of docetaxel-based chemotherapy appear to be inferior to the 3-weekly one in terms of quality of life in patients with locally advanced or metastatic breast cancer. Trial registration ClinicalTrials.gov NCT00540800.

  16. Mode Selection in Flame-Vortex driven Combustion Instabilities

    KAUST Repository

    Speth, Ray

    2011-01-04

    In this paper, we investigate flame-vortex interaction in a lean premixed, laboratory scale, backward-facing step combustor. Two series of tests were conducted, using propane/hydrogen mixtures and carbon monoxide/hydrogen mixtures as fuels, respectively. Pressure measurements and high speed particle imaging velocimetry (PIV) were employed to generate pressure response curves as well as the images of the velocity field and the flame brush. We demonstrate that the step combustor exhibits several operating modes depending on the inlet conditions and fuel composition, characterized by the amplitude and frequency of pressure oscillations along with distinct dynamic flame shapes. We propose a model in which the combustor\\'s selection of the acoustic mode is governed by a combustion-related time delay inversely proportional to the flame speed. Our model predicts the transition between distinct operating modes. We introduce non-dimensional parameters characterizing the flame speed and stretch rate, and develop a relationship between these quantities at the operating conditions corresponding to each mode transition. Based on this relationship, we show that numerically-calculated density-weighted strained flame speed can be used to collapse the combustion dynamics data over the full range of conditions (inlet temperature, fuel composition, and equivalence ratio). Finally, we validate our strain flame based model by measuring the strain rate using the flame image and the velocity field from the PIV measurement. Our results show that the measured strain rates lie in the same range as the critical values at the transitions among distinct modes as those predicted by our model.

  17. Environmental fate & effects of new generation flame retardants

    OpenAIRE

    Voogt, de, P.; Admiraal, W; Parsons, J.R.; Kraak, M.H.S.; Waaijers, S.L.

    2014-01-01

    There is a pressing need for substituting several halogenated flame retardants, given the human and environmental health concerns of many of these compounds. Halogen Free Flame Retardants (HFFRs) have been suggested as alternatives and are already being marketed, although their potential impact on the environment cannot be properly assessed because of a lack of information regarding their environmental and ecotoxicological properties. The aim of this study was to determine the aquatic fate an...

  18. Porous Flame-retarded Asphalt Pavement for Highway Tunnel

    Institute of Scientific and Technical Information of China (English)

    HU Shuguang; HUANG Shaolong; Ding Qingjun

    2008-01-01

    A new way to improve the tunnel fire protection by using flame-retarded porous asphalt pavement containing ATH powders was introduced. Based on the miniature burning test designed and conducted, the burning time and temperature of porous asphalt (PA) and flame-retarded porous asphalt (FRPA) were studied comparing with cement concrete pavement, dense-graded HMA and S MA. Results of burning test and pavement performance test indicate that FRPA is appropriate and suitable as the pavement material of highway tunnel.

  19. Direct and Convenient Mass Spectrometry Sampling with Ambient Flame Ionization

    OpenAIRE

    Xiao-Pan Liu; Hao-Yang Wang; Jun-Ting Zhang; Meng-Xi Wu; Wan-Shu Qi; Hui Zhu; Yin-Long Guo

    2015-01-01

    Recent innovations in ambient ionization technology for the direct analysis of various samples in their native environment facilitate the development and applications of mass spectrometry in natural science. Presented here is a novel, convenient and flame-based ambient ionization method for mass spectrometric analysis of organic compounds, termed as the ambient flame ionization (AFI) ion source. The key features of AFI ion source were no requirement of (high) voltages, laser beams and spray g...

  20. Flame retardancy of paulownia wood and its mechanism

    OpenAIRE

    Li, Peng; Oda, Juhachi

    2007-01-01

    Paulownia wood (Pauloumia tomentosa) is a special kind of wood material in that it has especially excellent flame retardancy. Using this property, it has been commonly used to make clothing wardrobes for a long time in Japan. In this research, the flame retardancy of paulownia wood has been verified by heating experiments and cone calorimeter testing. The structure and tissue of the material have been analyzed by scanning electron microscope and other methods. Moreover, the mechanism of the f...

  1. Effect of Electric Field on Outwardly Propagating Spherical Flame

    KAUST Repository

    Mannaa, Ossama

    2012-06-01

    The thesis comprises effects of electric fields on a fundamental study of spheri­cal premixed flame propagation.Outwardly-propagating spherical laminar premixed flames have been investigated in a constant volume combustion vessel by applying au uni-directional electric potential.Direct photography and schlieren techniques have been adopted and captured images were analyzed through image processing. Unstretched laminar burning velocities under the influence of electric fields and their associated Markstein length scales have been determined from outwardly prop­agating spherical flame at a constant pressure. Methane and propane fuels have been tested to assess the effect of electric fields on the differential diffusion of the two fuels.The effects of varying equivalence ratios and applied voltages have been in­vestigated, while the frequency of AC was fixed at 1 KHz. Directional propagating characteristics were analyzed to identify the electric filed effect. The flame morphology varied appreciably under the influence of electric fields which in turn affected the burning rate of mixtures.The flame front was found to propagate much faster toward to the electrode at which the electric fields were supplied while the flame speeds in the other direction were minimally influenced. When the voltage was above 7 KV the combustion is markedly enhanced in the downward direction since intense turbulence is generated and as a result the mixing process or rather the heat and mass transfer within the flame front will be enhanced.The com­bustion pressure for the cases with electric fields increased rapidly during the initial stage of combustion and was relatively higher since the flame front was lengthened in the downward direction.

  2. Quantification of extinction mechanism in counterflow premixed flames

    KAUST Repository

    Choi, Sangkyu

    2014-09-01

    The extinction mechanisms of stretched premixed flames have been investigated numerically for the fuels of CH4, C3H8, H2, CO and for the mixture fuels of CH4+H2 and CO+H2 by adopting symmetric double premixed flames in a counterflow configuration. The local equilibrium temperature concept was used as a measure of energy loss or gain in order to quantify the extinction mechanism by preferential diffusion and/or incomplete reaction. The energy loss ratio from preferential diffusion arising from non-unity Lewis number and the loss ratio from incomplete reaction were calculated at various equivalence ratios near flame extinction. The results showed that the extinction of lean H2, CH4, CH4+H2, CO+H2, and rich C3H8 premixed flames was caused by incomplete reaction due to insufficient reaction time, indicating that the effective Lewis number was smaller than unity, while the effect of preferential diffusion resulted in energy gain. However, the extinction of rich H2, CH4, CH4+H2, CO+H2, and lean C3H8 premixed flames was affected by the combined effects of preferential diffusion and incomplete reaction indicating that the effective Lewis number was larger than unity. In CO premixed flames, incomplete reaction was dominant in both lean and rich cases due to the effective Lewis number close to unity. The effect of H2 mixing to CO is found to be quite significant as compared to CH4+H2 cases, which can alter the flame behavior of CO flames to that of H2.

  3. Armazenamento refrigerado de pomelos variedades flame e henderson revestidos com cera Refrigerated storage of wax-coated grapefruit varieties Flame and Henderson

    Directory of Open Access Journals (Sweden)

    Ellen Toews Doll Hojo

    2010-10-01

    Full Text Available Objetivou-se, neste trabalho, estudar a conservação de pomelos (Citrus paradisi Macfad. varieties 'Flame' e 'Henderson' revestidos com cera Sparcitrus e mantidos sob refrigeração (8º C ± 1º C e 95% ± 5% UR. Para cada variedade estudada, utilizou-se delineamento inteiramente casualizado, disposto em esquema fatorial 2 x 5, com 3 repetições, onde o primeiro fator correspondeu aos tratamentos com e sem a aplicação de cera (controle e o segundo, ao tempo armazenamento (0, 10, 20, 30 e 40 dias. Cada parcela experimental foi composta por cinco frutos. Foram estudadas as seguintes variáveis: perda de massa, rendimento do suco, pH, sólidos solúveis (SS, acidez titulável (AT, SS/AT, açúcares redutores, açúcares não redutores, açúcares solúveis totais, vitamina C e aparência externa. A aplicação de cera é efetiva na preservação da aparência de pomelos 'Flame' e 'Henderson', não afetando sua qualidade interna.The goal of this work was to study the conservation of grapefruit (Citrus paradisi Macfad. "Flame" and "Henderson" coated with Sparcitrus wax and kept under refrigeration (8º C ± 1º C and 95% ± 5% RH. For each variety studied, the experimental design was completely randomized, build up in factorial 2 x 5, with 3 replicates, where the first factor corresponded to the treatments with and without wax application (control and the second factor to the storage period (0, 10, 20, 30 and 40 days. Each experimental parcel was composed of five fruits. The following variables were studied: mass loss, yield of juice, pH, soluble solids (SS, titratable acidity (TA, SS/AT, reducing, non-reducing and total soluble sugars, ascorbic acid and external appearance. Wax application is effective in the preservation of the appearance of grapefruits "Flame" and "Henderson", and does not affect their internal quality.

  4. Advance Payment ACO Model

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Advance Payment Model is designed for physician-based and rural providers who have come together voluntarily to give coordinated high quality care to the...

  5. SU-E-T-205: Improving Quality Assurance of HDR Brachytherapy: Verifying Agreement Between Planned and Delivered Dose Distributions Using DICOM RTDose and Advanced Film Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A L [Portsmouth Hospitals NHS Trust, Portsmouth, Hampshire (United Kingdom); University of Surrey, Guildford, Surrey (United Kingdom); Bradley, D A [University of Surrey, Guildford, Surrey (United Kingdom); Nisbet, A [University of Surrey, Guildford, Surrey (United Kingdom); Royal Surrey County Hospital NHS Foundation Trust, Guildford, Surrey (United Kingdom)

    2014-06-01

    Purpose: HDR brachytherapy is undergoing significant development, and quality assurance (QA) checks must keep pace. Current recommendations do not adequately verify delivered against planned dose distributions: This is particularly relevant for new treatment planning system (TPS) calculation algorithms (non TG-43 based), and an era of significant patient-specific plan optimisation. Full system checks are desirable in modern QA recommendations, complementary to device-centric individual tests. We present a QA system incorporating TPS calculation, dose distribution export, HDR unit performance, and dose distribution measurement. Such an approach, more common in external beam radiotherapy, has not previously been reported in the literature for brachytherapy. Methods: Our QA method was tested at 24 UK brachytherapy centres. As a novel approach, we used the TPS DICOM RTDose file export to compare planned dose distribution with that measured using Gafchromic EBT3 films placed around clinical brachytherapy treatment applicators. Gamma analysis was used to compare the dose distributions. Dose difference and distance to agreement were determined at prescription Point A. Accurate film dosimetry was achieved using a glass compression plate at scanning to ensure physically-flat films, simultaneous scanning of known dose films with measurement films, and triple-channel dosimetric analysis. Results: The mean gamma pass rate of RTDose compared to film-measured dose distributions was 98.1% at 3%(local), 2 mm criteria. The mean dose difference, measured to planned, at Point A was -0.5% for plastic treatment applicators and -2.4% for metal applicators, due to shielding not accounted for in TPS. The mean distance to agreement was 0.6 mm. Conclusion: It is recommended to develop brachytherapy QA to include full-system verification of agreement between planned and delivered dose distributions. This is a novel approach for HDR brachytherapy QA. A methodology using advanced film

  6. Testicular radiation dose after multimodal curative therapy for locally advanced rectal cancer. Influence on hormone levels, quality of life, and sexual functioning

    Energy Technology Data Exchange (ETDEWEB)

    Hennies, S.; Wolff, H.A.; Rave-Fraenk, M.; Hess, C.F. [University Medicine Goettingen (Germany). Dept. of Radiotherapy; Jung, K. [University Medicine Goettingen (Germany). Dept. of Medical Statistics; Gaedcke, J.; Ghadimi, M.; Becker, H. [University Medicine Goettingen (Germany). Dept. of General Surgery; Hermann, R.M. [University Medicine Goettingen (Germany). Dept. of Radiotherapy; Aerztehaus an der Ammerlandklinik, Westerstede (Germany). Radiotherapy; Christiansen, H. [University Medicine Goettingen (Germany). Dept. of Radiotherapy; Hannover Medical School (Germany). Dept. of Radiotherapy

    2012-10-15

    Purpose: The purpose of the current work was to prospectively measure the influence of testicular radiation dose on hormone levels, quality of life (QoL), and sexual functioning following multimodal therapy (neoadjuvant radiochemotherapy, surgery, and adjuvant chemotherapy) for rectal cancer. Patients and methods: From November 2007 to November 2009, 83 male patients were treated at the University of Goettingen with radiochemotherapy (RCT) for locally advanced rectal cancer [total dose 50.4 Gy, concomitant chemotherapy with two cycles of 5-fluorouracil (FU) or 5-FU and oxaliplatin]. Testicular radiation doses were analyzed and correlated with hormone levels [luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone and free androgen index (FAI) serum levels], QoL, and sexual functioning, which were determined before and up to 1 year after RCT. Results: Mean dose at the testes was 3.9 Gy (range 0.28-11.98 Gy). It was higher for tumors located < 6 cm from the anocutaneous line (p < 0.05). One year after therapy, testosterone, the testosterone/LH ratio, and the FAI/LH ratio were significantly decreased (3.5-3.0 {mu}g/l, 0.9-0.4, 7.9-4.5, respectively) while LH and FSH (4.2-8.5 IU/l, 6.0-21.9 IU/l) were increased. QoL and sexual functioning were significantly impaired. However, there was no statistical correlation between testicular radiation dose and changes in hormone levels, QoL, or sexual functioning. Conclusion: Multimodal treatment for rectal cancer including RCT leads to hormone level changes and to impaired QoL and sexual functioning. However, because there was no apparent correlation between the analyzed parameters, QoL is probably also influenced by other factors, e.g., psychosocial aspects. (orig.)

  7. SU-E-T-205: Improving Quality Assurance of HDR Brachytherapy: Verifying Agreement Between Planned and Delivered Dose Distributions Using DICOM RTDose and Advanced Film Dosimetry

    International Nuclear Information System (INIS)

    Purpose: HDR brachytherapy is undergoing significant development, and quality assurance (QA) checks must keep pace. Current recommendations do not adequately verify delivered against planned dose distributions: This is particularly relevant for new treatment planning system (TPS) calculation algorithms (non TG-43 based), and an era of significant patient-specific plan optimisation. Full system checks are desirable in modern QA recommendations, complementary to device-centric individual tests. We present a QA system incorporating TPS calculation, dose distribution export, HDR unit performance, and dose distribution measurement. Such an approach, more common in external beam radiotherapy, has not previously been reported in the literature for brachytherapy. Methods: Our QA method was tested at 24 UK brachytherapy centres. As a novel approach, we used the TPS DICOM RTDose file export to compare planned dose distribution with that measured using Gafchromic EBT3 films placed around clinical brachytherapy treatment applicators. Gamma analysis was used to compare the dose distributions. Dose difference and distance to agreement were determined at prescription Point A. Accurate film dosimetry was achieved using a glass compression plate at scanning to ensure physically-flat films, simultaneous scanning of known dose films with measurement films, and triple-channel dosimetric analysis. Results: The mean gamma pass rate of RTDose compared to film-measured dose distributions was 98.1% at 3%(local), 2 mm criteria. The mean dose difference, measured to planned, at Point A was -0.5% for plastic treatment applicators and -2.4% for metal applicators, due to shielding not accounted for in TPS. The mean distance to agreement was 0.6 mm. Conclusion: It is recommended to develop brachytherapy QA to include full-system verification of agreement between planned and delivered dose distributions. This is a novel approach for HDR brachytherapy QA. A methodology using advanced film

  8. Testicular radiation dose after multimodal curative therapy for locally advanced rectal cancer. Influence on hormone levels, quality of life, and sexual functioning

    International Nuclear Information System (INIS)

    Purpose: The purpose of the current work was to prospectively measure the influence of testicular radiation dose on hormone levels, quality of life (QoL), and sexual functioning following multimodal therapy (neoadjuvant radiochemotherapy, surgery, and adjuvant chemotherapy) for rectal cancer. Patients and methods: From November 2007 to November 2009, 83 male patients were treated at the University of Goettingen with radiochemotherapy (RCT) for locally advanced rectal cancer [total dose 50.4 Gy, concomitant chemotherapy with two cycles of 5-fluorouracil (FU) or 5-FU and oxaliplatin]. Testicular radiation doses were analyzed and correlated with hormone levels [luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone and free androgen index (FAI) serum levels], QoL, and sexual functioning, which were determined before and up to 1 year after RCT. Results: Mean dose at the testes was 3.9 Gy (range 0.28-11.98 Gy). It was higher for tumors located < 6 cm from the anocutaneous line (p < 0.05). One year after therapy, testosterone, the testosterone/LH ratio, and the FAI/LH ratio were significantly decreased (3.5-3.0 μg/l, 0.9-0.4, 7.9-4.5, respectively) while LH and FSH (4.2-8.5 IU/l, 6.0-21.9 IU/l) were increased. QoL and sexual functioning were significantly impaired. However, there was no statistical correlation between testicular radiation dose and changes in hormone levels, QoL, or sexual functioning. Conclusion: Multimodal treatment for rectal cancer including RCT leads to hormone level changes and to impaired QoL and sexual functioning. However, because there was no apparent correlation between the analyzed parameters, QoL is probably also influenced by other factors, e.g., psychosocial aspects. (orig.)

  9. Numerical study of flame structure in the mild combustion regime

    Directory of Open Access Journals (Sweden)

    Mardani Amir

    2015-01-01

    Full Text Available In this paper, turbulent non-premixed CH4+H2 jet flame issuing into a hot and diluted co-flow air is studied numerically. This flame is under condition of the moderate or intense low-oxygen dilution (MILD combustion regime and related to published experimental data. The modelling is carried out using the EDC model to describe turbulence-chemistry interaction. The DRM-22 reduced mechanism and the GRI2.11 full mechanism are used to represent the chemical reactions of H2/methane jet flame. The flame structure for various O2 levels and jet Reynolds numbers are investigated. The results show that the flame entrainment increases by a decrease in O2 concentration at air side or jet Reynolds number. Local extinction is seen in the upstream and close to the fuel injection nozzle at the shear layer. It leads to the higher flame entertainment in MILD regime. The turbulence kinetic energy decay at centre line of jet decreases by an increase in O2 concentration at hot Co-flow. Also, increase in jet Reynolds or O2 level increases the mixing rate and rate of reactions.

  10. Upgrading of recycled polypropylene by preparing flame retarded layered composite

    Directory of Open Access Journals (Sweden)

    F. Ronkay

    2012-11-01

    Full Text Available Upgrading of polypropylene waste was performed by different composite technologies, in order to improve the flame retardancy combined with preserved or improved mechanical properties. The polymer waste of density below 900 kg/m3 is originated from end-of-life vehicles (ELV after comminution, density separation and comprehensive analysis. Intumescent flame retardant system was used for reducing the flammability; while chopped glass fibre reinforcement was used to compensate the deterioration of mechanical properties caused by flame retardant additives. In mixed composite beside of flame retardants, the reinforcement effect of glass fibre can not be realized; therefore with modification of composite structure (but maintaining the composition a multilayer composite was developed, which contains 65.5% of recycled polymer, where the core is reinforced with glass fibre covered by flame retarded shell layers. Enhanced flame retardancy (4 min longer time to escape was achieved by using this layered composite compared to the mixed composite, thus the time to escape could be extended only with modification of composite structure.

  11. Ion measurements in premixed methane-oxygen flames

    KAUST Repository

    Alquaity, Awad

    2014-07-25

    Ions are formed as a result of chemi-ionization processes in combustion systems. Recently, there has been an increasing interest in understanding flame ion chemistry due to the possible application of external electric fields to reduce emissions and improve combustion efficiency by active control of combustion process. In order to predict the effect of external electric fields on combustion plasma, it is critical to gain a good understanding of the flame ion chemistry. In this work, a Molecular Beam Mass Spectrometer (MBMS) is utilized to measure ion concentration profiles in premixed methane-oxygen-argon burner-stabilized flames. Lean, stoichiometric and rich flames at atmospheric pressure are used to study the dependence of ion chemistry on equivalence ratio of premixed flames. The relative ion concentration profiles are compared qualitatively with previous methane-oxygen studies and show good agreement. The relative ion concentration data obtained in the present study can be used to validate and improve ion chemistry models for methane-oxygen flames.

  12. Turbulent Chemical Diffusion in Convectively Bounded Carbon Flames

    CERN Document Server

    Lecoanet, Daniel; Quataert, Eliot; Bildsten, Lars; Timmes, F X; Burns, Keaton J; Vasil, Geoffrey M; Oishi, Jeffrey S; Brown, Benjamin P

    2016-01-01

    It has been proposed that mixing induced by convective overshoot can disrupt the inward propagation of carbon deflagrations in super-asymptotic giant branch stars. To test this theory, we study an idealized model of convectively bounded carbon flames with 3D hydrodynamic simulations of the Boussinesq equations using the pseudospectral code Dedalus. Because the flame propagation timescale is $\\sim 10^5$ times longer than the convection timescale, we approximate the flame as fixed in space, and only consider its effects on the buoyancy of the fluid. By evolving a passive scalar field, we derive a turbulent chemical diffusivity produced by the convection as a function of height, $D_t(z)$. Convection can stall a flame if the chemical mixing timescale, set by the turbulent chemical diffusivity, $D_t$, is shorter than the flame propagation timescale, set by the thermal diffusivity, $\\kappa$, i.e., when $D_t>\\kappa$. However, we find $D_t<\\kappa$ for most of the flame because convective plumes are not dense enoug...

  13. Vorticity transformation in high Karlovitz number premixed flames

    Science.gov (United States)

    Bobbitt, Brock; Lapointe, Simon; Blanquart, Guillaume

    2016-01-01

    To better understand the two-way coupling between turbulence and chemistry, the changes in turbulence characteristics through a premixed flame are investigated. Specifically, this study focuses on vorticity, ω, which is characteristic of the smallest length and time scales of turbulence, analyzing its behavior within and across high Karlovitz number (Ka) premixed flames. This is accomplished through a series of direct numerical simulations (DNS) of premixed n-heptane/air flames, modeled with a 35-species finite-rate chemical mechanism, whose conditions span a wide range of unburnt Karlovitz numbers and flame density ratios. The behavior of the terms in the enstrophy, ω2 = ω ṡ ω, transport equation is analyzed, and a scaling is proposed for each term. The resulting normalized enstrophy transport equation involves only a small set of parameters. Specifically, the theoretical analysis and DNS results support that, at high Karlovitz number, enstrophy transport obtains a balance of the viscous dissipation and production/vortex stretching terms. It is shown that, as a result, vorticity scales in the same manner as in homogeneous, isotropic turbulence within and across the flame, namely, scaling with the inverse of the Kolmogorov time scale, τη. As τη is a function only of the viscosity and dissipation rate, this work supports the validity of Kolmogorov's first similarity hypothesis in premixed turbulent flames for sufficiently high Ka numbers. Results are unaffected by the transport model, chemical model, turbulent Reynolds number, and finally the physical configuration.

  14. Conditional moment closure modeling of a lifted turbulent flame

    Institute of Scientific and Technical Information of China (English)

    JIANG Yong; QIU Rong; ZHOU Wei; FAN Weicheng

    2005-01-01

    Results obtained using conditional moment closure (CMC) approach to modeling a lifted turbulent hydrogen flame are presented. Predictions are based on k-ε-g turbulent closure, a 23-step chemical mechanism and a radially averaged CMC model. The objectives are to find out how radially averaged CMC can represent a lifted flame and which mechanism of flame stabilization can be described by this modeling method. As a first stage of the study of multi-dimensional CMC for large eddy simulation (LES) of the lifted turbulent flames, the effect of turbulence upon combustion is included, the high-order compact finite- difference scheme (Padé) is used and previously developed characteristic-wave-based boundary conditions for multi- component perfect gas mixtures are here extended to their conditional forms but the heat release due to combustion is not part of the turbulent calculations. Attention is focused to the lift-off region of the flame which is commonly considered as a cold flow. Comparison with published experimental data and the computational results shows that the lift-off height can be accurately determined, and Favre averaged radial profiles of temperature and species mole fractions are also reasonably well predicted. Some of the current flame stabilization mechanisms are discussed.

  15. Flame resistant cellulosic substrate using banana pseudostem sap

    Directory of Open Access Journals (Sweden)

    Basak S.

    2015-03-01

    Full Text Available Flame retardancy was imparted in cellulosic cotton textile using banana pseudostem sap (BPS, an eco-friendly natural product. The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of both the control and the treated fabrics were analysed in terms of limiting oxygen index (LOI, horizontal and vertical flammability. Fabrics treated with the non-diluted BPS were found to have good flame retardant property with LOI of 30 compared to the control fabric with LOI of 18, i.e., an increase of 1.6 times. In the vertical flammability test, the BPS treated fabric showed flame for a few seconds and then, got extinguished. In the horizontal flammability test, the treated fabric showed no flame, but was burning only with an afterglow with a propagation rate of 7.5 mm/min, which was almost 10 times lower than that noted with the control fabric. The thermal degradation and the pyrolysis of the fabric samples were studied using a thermogravimetric analysis (TGA, and the chemical composition by FTIR, SEM and EDX, besides the pure BPS being characterized by EDX and mass spectroscopy. The fabric after the treatment was found to produce stable natural khaki colour, and there was no significant degradation in mechanical strengths. Based on the results, the mechanism of imparting flame retardancy to cellulosic textile and the formation of natural colour on it using the proposed BPS treatment have been postulated.

  16. Characteristics of flame spread over the surface of charring solid combustibles at high altitude

    Institute of Scientific and Technical Information of China (English)

    LI Jie; JI Jie; ZHANG Ying; SUN JinHua

    2009-01-01

    To explore the characteristics of flame spread over the surface of charring solid combustibles at high altitude, the whitewood with uniform texture was chosen to conduct a series of experiments in Lhasa and Hefei, with altitude of 3658 m and 50 m respectively. Several parameters, including the flame height, flame spread rate, flame temperature, surface temperature, were measured on samples with different width and inclinations. A quantitative analysis of flame spread characteristics over sample surface at high altitude was performed. Results showed that, in the environment of lower pressure and oxygen concentration at high altitude, the flame height and flame spread rate over sample surface decreased, but the flame temperature increased slightly. However, with increasing of sample width, the relative difference between the flame spread rates at different altitudes decreased.

  17. Experimental study of flame microstructure and propagation behavior of mine-gas explosion

    Institute of Scientific and Technical Information of China (English)

    CHEN Xian-feng; ZHANG Jian-hua; WANG Yu-jie; REN Shao-feng

    2008-01-01

    The high speed cameral and schlieren images methods were used to record the photograph of flame propagation process. Meanwhile, the ionization current probes were set up to detect the reaction intensity of the reaction zone. The characteristics of methane/air flame propagation and microstructure were analyzed in detail by the experi-mental results coupled with chemical reaction thermodynamics. The high speed schlieren image showed the transition from laminar flame to turbulence combustion. The ion current curves disclosed the reaction intensity and combustion characteristic of flame front. In the test, the particular tulip flame was formed clearly, which was induced to some extent by turbulent combustion. Based on the schlieren images and iron current result, it can be drawn that the small scale turbulence combustion also appears in laminar flame, which thickens the flame front, but makes little influence on the flame front shape. During the laminar-turbulent transition, the explosion pressure plays an important role on the flame structure change.

  18. Influence of gas compression on flame acceleration in the early stage of burning in tubes

    CERN Document Server

    Valiev, Damir; Kuznetsov, Mikhail; Eriksson, Lars-Erik; Law, Chung K; Bychkov, Vitaly

    2012-01-01

    The mechanism of finger flame acceleration at the early stage of burning in tubes has been observed experimentally by Clanet and Searby [Combust. Flame 105: 225 (1996)] for slow propane-air flames, and elucidated analytically and computationally by Bychkov et al. [Combust. Flame 150: 263 (2007)] in the limit of an incompressible flow. We analytically, experimentally and computationally study herein the finger flame acceleration for fast burning flames, when the gas compressibility assumes an important role. Specifically, we have developed a theory through small Mach number expansion up to the first-order terms, demonstrating that gas compression reduces the acceleration rate and thereby moderates the finger flame acceleration noticeably. We have also conducted experiments for hydrogen-oxygen mixtures with considerable initial values of the Mach number, showing finger flame acceleration with the acceleration rate much smaller than those obtained previously for hydrocarbon flames. Furthermore, we have performed...

  19. Laminar premixed methane/air flame extinction characteristics influenced by co-flow water mists

    Institute of Scientific and Technical Information of China (English)

    LIU XuanYa; LU ShouXiang; ZHU YingChun; LIU Yi

    2008-01-01

    Based on the tubular burner, the burning velocities, flame stretch and inhibition rules influenced by co-flow water mists were studied using a high-speed schlieren system. Moreover, the variation rules of the flame critical extinction in our burner equipment were also obtained by analyzing the process and mechanism of flame extinction and inhibition. It is shown that the flame stretch is related to the fuel concentration, co-flow fluxes and water mist diameters. For droplets with a larger diameter, the smaller the co-flow fluxes, the more obvious the flame stretch. When the water mist loading rate is rather smaller, for fuel-rich premixed flame with Le>1, the flame with larger burning rate tends to backfire more easily. Under the same water mist conditions, for fuel-lean premixed flame with Le<1, the smaller the gas concentration, the easier the flame is extinct.

  20. Thermal properties of flame retardant cotton fabric grafted by dimethyl methacryloyloxyethyl phosphate

    Directory of Open Access Journals (Sweden)

    Xing Tie-Ling

    2012-01-01

    Full Text Available Thermal properties of flame retardant cotton fabric grafted by dimethyl methacryloy-loxyethyl phosphate were investigated by the atom transfer radical polymerization method. Thermal gravimetric analysis was used to explore the thermal decomposition mode of flamed retardant cotton fabric. The weight loss rate of the flamed retardant cotton was bigger than that of the control cotton fabric, and a more final residual char of flamed retardant cotton was also observed. Flammability tests were used to study the flame retardance property of the flame retardant cotton fabric. The results showed that flamed retardant cotton fabric with 16.8% of weight gain could keep good flame retardance. Scanning electron microscope pictures were applied to investigate the morphology of residual char of the flame retardant samples.

  1. Enhancement of flame development by microwave-assisted spark ignition in constant volume combustion chamber

    KAUST Repository

    Wolk, Benjamin

    2013-07-01

    The enhancement of laminar flame development using microwave-assisted spark ignition has been investigated for methane-air mixtures at a range of initial pressures and equivalence ratios in a 1.45. l constant volume combustion chamber. Microwave enhancement was evaluated on the basis of several parameters including flame development time (FDT) (time for 0-10% of total net heat release), flame rise time (FRT) (time for 10-90% of total net heat release), total net heat release, flame kernel growth rate, flame kernel size, and ignitability limit extension. Compared to a capacitive discharge spark, microwave-assisted spark ignition extended the lean and rich ignition limits at all pressures investigated (1.08-7.22. bar). The addition of microwaves to a capacitive discharge spark reduced FDT and increased the flame kernel size for all equivalence ratios tested and resulted in increases in the spatial flame speed for sufficiently lean flames. Flame enhancement is believed to be caused by (1) a non-thermal chemical kinetic enhancement from energy deposition to free electrons in the flame front and (2) induced flame wrinkling from excitation of flame (plasma) instability. The enhancement of flame development by microwaves diminishes as the initial pressure of the mixture increases, with negligible flame enhancement observed above 3. bar. © 2013 The Combustion Institute.

  2. Effect of fuel mixture fraction and velocity perturbations on the flame transfer function of swirl stabilized flames

    Science.gov (United States)

    Wysocki, Stefan; Di-Chiaro, Giacomo; Biagioli, Fernando

    2015-11-01

    A novel methodology is developed to decompose the classic Flame Transfer Function (FTF) used in the thermo-acoustic stability analysis of lean premix combustors into contributions of different types. The approach is applied, in the context of Large Eddy Simulation (LES), to partially-premixed and fully-premixed flames, which are stabilized via a central recirculation zone as a result of the vortex breakdown phenomenon. The first type of decomposition is into contributions driven by fuel mixture fraction and dynamic velocity fluctuations. Each of these two contributions is further split into the components of turbulent flame speed and flame surface area. The flame surface area component, driven by the pure dynamic velocity fluctuation, which is shown to be a dominant contribution to the overall FTF, is also additionally decomposed over the coherent flow structures using proper orthogonal decomposition. Using a simplified model for the dynamic response of premixed flames, it is shown that the distribution of the FTF, as obtained from LES, is closely related to the characteristics of the velocity field frequency response to the inlet perturbation. Initially, the proposed method is tested and validated with a well characterized laboratory burner geometry. Subsequently, the method is applied to an industrial gas turbine burner.

  3. Flame burn protection: assessment of a new, air-cooled fireproof garment.

    Science.gov (United States)

    Eldad, Arieh; Salmon, Ashi Y; Breiterman, Semion; Chaouat, Malka; BenBassat, Hannah

    2003-08-01

    A new, air-cooled fireproof garment for tank crewmen was assessed regarding its efficacy for burn protection. A pig model was developed with a flame infliction instrument specially designed for this experiment. This pneumatic tool can initiate eight simultaneous flame injuries where the distance of skin from burn source and exposure time are adjustable. In the study, 1,000 degrees C, 5-second exposure flame burns were inflicted upon anesthetized pigs. Full-thickness injuries were caused to exposed animals or to animals that were protected by the single layer of old type Nomex protective garments. On day 21, the original burn size diminished to 42.3% +/- 6.3% and 41.2% +/- 7.9%, respectively. When the animals were dressed with the new type of air-cooled Nomex, only small and superficial burns could be detected when the air compressor was operating, and moderate burns were demonstrated when the compressor was not working. On day 21, postburn original burn size was diminished to 1.9% +/- 1.9% and to 17% +/- 6.5%, respectively. Quantitative burn wound histology followed the same trends with almost normal skin architecture after 7 days in the air-inflated new garments, moderate pathology, and an advanced wound healing process in the affected area when the compressor was not working and severe damage with only initial wound healing in the exposed skin or the areas that were protected by old type, single-layered fireproof garments. This new type of air-cooled fireproof garment was significantly better than the old garment under the experiment condition and seems to be very promising in burn prevention among tank crewmen. PMID:12943032

  4. Application of reservoir characterization and advanced technology to improve recovery and economics in a lower quality shallow shelf San Andres Reservoir. Quarterly Report for the period: 1 April - 30 June 2001

    International Nuclear Information System (INIS)

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO2) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents

  5. Influence of rarefaction wave on premixed flame structure and propagation behavior

    Institute of Scientific and Technical Information of China (English)

    CHEN Xianfeng; SUN Jinhua; LU Shouxiang; CHU Guanquan; YAO Liyin; LIU Yi

    2007-01-01

    To explore the influence of rarefaction wave on the structure and propagation behavior of the premixed propane/air flame in a rectangle combustion pipe, the techniques of high speed Schlieren photograph method, pressure measurement and so on are used to study the interaction processes between rarefaction wave and flame. Two cases of rarefaction wave-flame interaction were performed in the experiment. The experimental result shows that both the rarefaction waves can cause the flame transition from laminar to turbulent combustion quickly. The cowflow rarefaction wave decreases the flame speed, while the counterflow rarefaction wave leads the flame propagation speed to increasing on the whole, accompanied with sharp vibration.

  6. A visualization study of Rayleigh-Taylor instability of flames generated by sudden acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Ma, L.; Yao, X.; Chomiak, J. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Thermo- and Fluid Dynamics

    1996-07-01

    The Rayleigh-Taylor instability phenomenon occurs in flames when the pressure in the products is higher than in the mixture. The development of this phenomenon in premixed flames was investigated experimentally. A square glass tube for standard flammability limit studies and a methane air mixture were used in the experiment. The flame was accelerated by a falling piston and flame shapes and positions were recorded. Results showed that sudden acceleration does not induce small scale instabilities of flame, contrary to predictions of existing linear theories. The accelerated flames form large scale bubbles which propagate with constant speed relative to the gas. 20 refs., 6 figs.

  7. Development of Nanosized/Nanostructured Silicon as Advanced Anodes for Lithium-Ion Cells

    Science.gov (United States)

    Wu, James J.

    2015-01-01

    NASA is developing high energy and high capacity Li-ion cell and battery designs for future exploration missions under the NASA Advanced Space Power System (ASPS) Program. The specific energy goal is 265 Wh/kg at 10 C. center dot Part of effort for NASA advanced Li-ion cells ? Anode: Silicon (Si) as an advanced anode. ? Electrolyte: advanced electrolyte with flame-retardant additives for enhanced performance and safety (NASA JPL).

  8. Refractory Materials for Flame Deflector Protection System Corrosion Control: Refractory Ceramics Literature Survey

    Science.gov (United States)

    Calle, Luz Marina; Hintze, Paul E.; Parlier, Christopher R.; Curran, Jerome P.; Kolody, Mark; Perusich, Stephen; Whitten, Mary C.; Trejo, David; Zidek, Jason; Sampson, Jeffrey W.; Coffman, Brekke E.

    2009-01-01

    Ceramics can be defmed as a material consisting of hard brittle properties produced from inorganic and nonmetallic minerals made by firing at high temperatures. These materials are compounds between metallic and nonmetallic elements and are either totally ionic, or predominately ionic but having some covalent character. This definition allows for a large range of materials, not all applicable to refractory applications. As this report is focused on potential ceramic materials for high temperature, aggressive exposure applications, the ceramics reviewed as part of this report will focus on refractory ceramics specifically designed and used for these applications. Ceramic materials consist of a wide variety of products. Callister (2000) 1 characterized ceramic materials into six classifications: glasses, clay products, refractories, cements, abrasives, and advanced ceramics. Figure 1 shows this classification system. This review will focus mainly on refractory ceramics and cements as in general, the other classifications are neither applicable nor economical for use in large structures such as the flame trench. Although much work has been done in advanced ceramics over the past decade or so, these materials are likely cost prohibitive and would have to be fabricated off-site, transported to the NASA facilities, and installed, which make these even less feasible. Although the authors reviewed the literature on advanced ceramic refractories 2 center dot 3 center dot 4 center dot 5 center dot 6 center dot 7 center dot 8 center dot 9 center dot 10 center dot 11 center dot 12 after the review it was concluded that these materials should not be ' the focus of this report. A review is in progress on materials and systems for prefabricated refractory ceramic panels, but this review is focusing more on typical refractory materials for prefabricated systems, which could make the system more economically feasible. Refractory ceramics are used for a wide variety of applications

  9. Aromatics Oxidation and Soot Formation in Flames

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J. B.; Richter, H.

    2005-03-29

    This project is concerned with the kinetics and mechanisms of aromatics oxidation and the growth process to polycyclic aromatic hydrocarbons (PAH) of increasing size, soot and fullerenes formation in flames. The overall objective of the experimental aromatics oxidation work is to extend the set of available data by measuring concentration profiles for decomposition intermediates such as phenyl, cyclopentadienyl, phenoxy or indenyl radicals which could not be measured with molecular-beam mass spectrometry to permit further refinement and testing of benzene oxidation mechanisms. The focus includes PAH radicals which are thought to play a major role in the soot formation process while their concentrations are in many cases too low to permit measurement with conventional mass spectrometry. The radical species measurements are used in critical testing and improvement of a kinetic model describing benzene oxidation and PAH growth. Thermodynamic property data of selected species are determined computationally, for instance using density functional theory (DFT). Potential energy surfaces are explored in order to identify additional reaction pathways. The ultimate goal is to understand the conversion of high molecular weight compounds to nascent soot particles, to assess the roles of planar and curved PAH and relationships between soot and fullerenes formation. The specific aims are to characterize both the high molecular weight compounds involved in the nucleation of soot particles and the structure of soot including internal nanoscale features indicative of contributions of planar and/or curved PAH to particle inception.

  10. CloudFlame: Cyberinfrastructure for combustion research

    KAUST Repository

    Goteng, Gokop

    2013-12-01

    Combustion experiments and chemical kinetics simulations generate huge data that is computationally and data intensive. A cloud-based cyber infrastructure known as Cloud Flame is implemented to improve the computational efficiency, scalability and availability of data for combustion research. The architecture consists of an application layer, a communication layer and distributed cloud servers running in a mix environment of Windows, Macintosh and Linux systems. The application layer runs software such as CHEMKIN modeling application. The communication layer provides secure transfer/archive of kinetic, thermodynamic, transport and gas surface data using private/public keys between clients and cloud servers. A robust XML schema based on the Process Informatics Model (Prime) combined with a workflow methodology for digitizing, verifying and uploading data from scientific graphs/tables to Prime is implemented for chemical molecular structures of compounds. The outcome of using this system by combustion researchers at King Abdullah University of Science and Technology (KAUST) Clean Combustion Research Center and its collaborating partners indicated a significant improvement in efficiency in terms of speed of chemical kinetics and accuracy in searching for the right chemical kinetic data.

  11. Azimuthally forced flames in an annular combustor

    Science.gov (United States)

    Worth, Nicholas; Dawson, James; Mastorakos, Epaminondas

    2015-11-01

    Thermoacoustic instabilities are more likely to occur in lean burn combustion systems, making their adoption both difficult and costly. At present, our knowledge of such phenomena is insufficient to produce an inherently stable combustor by design, and therefore an improved understanding of these instabilities has become the focus of a significant research effort. Recent experimental and numerical studies have demonstrated that the symmetry of annular chambers permit a range of self-excited azimuthal modes to be generated in annular geometry, which can make the study of isolated modes difficult. While acoustic forcing is common in single flame experiments, no equivalent for forced azimuthal modes in an annular chamber have been demonstrated. The present investigation focuses on the novel application of acoustic forcing to a laboratory scale annular combustor, in order to generate azimuthal standing wave modes at a prescribed frequency and amplitude. The results focus on the ability of the method to isolate the mode of oscillation using experimental pressure and high speed OH* measurements. The successful excitation of azimuthal modes demonstrated represents an important step towards improving our fundamental understanding of this phenomena in practically relevant geometry.

  12. Diamond growth in oxygen-acetylene flame

    International Nuclear Information System (INIS)

    What was supposed to be a laboratory curiosity in the 80's, in recent years the low pressure process for the production of man-made diamond turned out to be a major target for research and development of many high-tech companies. The main reason for such an interest stems on the possibility of coating many materials with a diamond film possessing the same amazing properties of the bulk natural diamond. Polycrystalline diamond film has been deposited on Mo substrate by using oxygen-acetylene flame of a welding torch. The substrate temperature has been held constant about 700deg C by means of a water cooled mount designed properly. Precision flowmeters have been used to control the flow ratio oxygen/acetylene, a key parameter for the success in diamond growth. Diamond has been detected by X-ray diffraction, a fast foolproof technique for crystal identification. Another method of analysis often used in Raman spectroscopy, which is able to exhibit amorphous structure besides crystalline phase. (author)

  13. Nanostructured coatings by liquid flame spraying

    International Nuclear Information System (INIS)

    Modifying surface properties has become a market of great potential. Self-cleaning, which customarily relies partly on hydrophilicity or hydrophobicity of the surface, has instigated investigation into many different means of modifying surfaces. This study investigates the feasibility of manufacturing a hydrophilic surface on glazed ceramic tile by means of liquid flame spraying. The tiles used were commercial domestic tiles. The hydrophilic surface was produced by synthesising nano-sized titanium dioxide (TiO2) particles from liquid precursors and depositing them on the surface of heated tiles. The treated tiles were subjected to ultra-violet radiation and their hydrophilic properties were evaluated by contact angle measurements. The surfaces of the tiles were investigated by scanning electron microscopy. The TiO2 particles were analysed by energy-dispersive spectrometry. The contact angle of water decreased significantly as a result of the treatment. The reason for this could be the nanostructured nature of the TiO2 particles on the surface of the tiles

  14. Rich methane premixed laminar flames doped with light unsaturated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Gueniche, H.A.; Glaude, P.A.; Dayma, G.; Fournet, R.; Battin-Leclerc, F. [Departement de Chimie-Physique des Reactions, Nancy University, CNRS, ENSIC, 1 rue Grandville, BP 20451, 54001 Nancy Cedex (France)

    2006-09-15

    The structure of three laminar premixed rich flames has been investigated: a pure methane flame and two methane flames doped by allene and propyne, respectively. The gases of the three flames contain 20.9% (molar) of methane and 33.4% of oxygen, corresponding to an equivalence ratio of 1.25 for the pure methane flame. In both doped flames, 2.49% of C{sub 3}H{sub 4} was added, corresponding to a ratio C{sub 3}H{sub 4}/CH{sub 4} of 12% and an equivalence ratio of 1.55. The three flames have been stabilized on a burner at a pressure of 6.7 kPa using argon as dilutant, with a gas velocity at the burner of 36 cm/s at 333 K. The concentration profiles of stable species were measured by gas chromatography after sampling with a quartz microprobe. Quantified species included carbon monoxide and dioxide, methane, oxygen, hydrogen, ethane, ethylene, acetylene, propyne, allene, propene, propane, 1,2-butadiene, 1,3-butadiene, 1-butene, isobutene, 1-butyne, vinylacetylene, and benzene. The temperature was measured using a PtRh (6%)-PtRh (30%) thermocouple settled inside the enclosure and ranged from 700 K close to the burner up to 1850 K. In order to model these new results, some improvements have been made to a mechanism previously developed in our laboratory for the reactions of C{sub 3}-C{sub 4} unsaturated hydrocarbons. The main reaction pathways of consumption of allene and propyne and of formation of C{sub 6} aromatic species have been derived from flow rate analyses. (author)

  15. Automatic, non-intrusive, flame detection in pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, M.D.; Mehta, S.A.; Moore, R.G. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering; Al-Himyary, T.J. [Al-Himyary Consulting Inc., Calgary, AB (Canada)

    2004-07-01

    Flames have been known to occur within small diameter pipes operating under conditions of high turbulent flow. Although there are several methods of flame detection, few offer remote, non-line-of-site detection. In particular, combustion cannot be detected in cases where flammable mixtures are carried in flare lines, storage tank vents, air drilling or improperly designed purging operations. Combustion noise is being examined as a means to address this problem. A study was conducted in which flames within a small diameter tube were automatically detected using high speed pressure measurements and a newly developed algorithm. Commercially available, high-pressure, dynamic-pressure transducers were used for the measurements. The results of an experimental study showed that combustion noise can be distinguished from other sources of noise by its inverse power law relationship with frequency. This paper presented a newly developed algorithm which provides early detection of flames when combined with high-speed pressure measurements. The algorithm can also separate combustion noise automatically from other sources of noise when combined with other filters. In this study, the noise generated by a fluttering check valve was attenuated using a stop band filter. This detection method was found to be very reliable under the conditions tests, as long as there was no flow restriction between the sensor and the flame. A flow restriction would have resulted in the detection of only the strongest flame noise. It was shown that acoustic flame detection can be applied successfully in flare stacks, industrial burners and turbine combustors. It can be 15 times more sensitive than optical or electrical methods in diagnosing combustion problems with lean burning combustors. It may also be the only method available in applications that require remote, non-line-of-sight detection. 11 refs., 3 tabs., 15 figs.

  16. Investigation of H2 Concentration and Combustion Instability Effects on the Kinetics of Strained Syngas Flames

    Energy Technology Data Exchange (ETDEWEB)

    Ahsan R. Choudhuri

    2006-08-07

    The flame extinction limits of syngas (H{sub 2}-CO) flames were measured using a twin-flame-counter-flow burner. Plots of Extinction limits vs. global stretch rates were generated at different mixture compositions and an extrapolation method was used to calculate the flame extinction limit corresponding to an experimentally unattainable zero-stretch condition. The zero-stretch extinction limit of H{sub 2}-CO mixtures decreases (from rich to lean) with the increase in H{sub 2} concentration in the mixture. The average difference between the measured flame extinction limit and the Le Chatelier's calculation is around {approx} 7%. The measured OH{sup -} chemiluminescent data indicates that regardless of mixture compositions the OH radical concentration reduces (within the experimental uncertainties) to an extinction value prior to the flame extinction. Flame extinction limits of H{sub 2}-CO mixtures measured in a flat-flame burner configuration also show a similar relation. Additionally, the measured laminar flame velocity close to the extinction indicates that regardless of fuel composition the premixed flame of hydrogen fuel blends extinguishes when the mixture laminar flame velocity falls below a critical value. The critical laminar flame velocity at extinction for H{sub 2}-CO premixed flames (measured in the flat flame burner configuration) is found to be 3.77({+-}0.38) cm/s. An externally perturbed H{sub 2}-CO twin flame was not experimentally achievable for the mixture conditions used in the present investigation. A slightest perturbation in the flow-field distorts the H{sub 2}-CO twin-flame. The flame becomes highly unstable with the introduction of an externally excited flow oscillation.

  17. Stabilization and structure of n-heptane tribrachial flames in axisymmetric laminar jets

    KAUST Repository

    Bisetti, Fabrizio

    2015-01-01

    A set of tribrachial flames of n-heptane/air is simulated with finite rate chemistry and detailed transport in a realistic laminar jet configuration for which experimental data are available. The flames differ by the temperature of the unburnt mixture and stabilization height, which controls the mixture fraction gradient ahead of the flame front. The simulations reproduce the lift-off heights in the experiments, showing that the flame stabilizes further downstream as the unburnt temperature decreases. For the lowest unburnt temperature, resulting in a weak mixture fraction gradient at the tribrachial point, positive stretch along the rich premixed wing leads to an increase in the rate of chemical reaction in the whole flame. The tribrachial flame burning velocity exceeds that in the unstretched, one-dimensional flame. For the highest temperature, the flame stabilizes closest to the nozzle. Large flame tilt, large mixture fraction gradient, and small radius of curvature lead to a reduction in the heat release rate and the flame propagates slower than its one-dimensional counterpart. The observed behavior is explained with a detailed analysis of the flame geometry, differential diffusion effects, flame stretch, and transport of heat and mass from the burnt gases to the flame front. © 2014 The Combustion Institute.

  18. Combustion Characteristics for Turbulent Prevaporized Premixed Flame Using Commercial Light Diesel and Kerosene Fuels

    Directory of Open Access Journals (Sweden)

    Mohamed S. Shehata

    2014-01-01

    Full Text Available Experimental study has been carried out for investigating fuel type, fuel blends, equivalence ratio, Reynolds number, inlet mixture temperature, and holes diameter of perforated plate affecting combustion process for turbulent prevaporized premixed air flames for different operating conditions. CO2, CO, H2, N2, C3H8, C2H6, C2H4, flame temperature, and gas flow velocity are measured along flame axis for different operating conditions. Gas chromatographic (GC and CO/CO2 infrared gas analyzer are used for measuring different species. Temperature is measured using thermocouple technique. Gas flow velocity is measured using pitot tube technique. The effect of kerosene percentage on concentration, flame temperature, and gas flow velocity is not linearly dependent. Correlations for adiabatic flame temperature for diesel and kerosene-air flames are obtained as function of mixture strength, fuel type, and inlet mixture temperature. Effect of equivalence ratio on combustion process for light diesel-air flame is greater than for kerosene-air flame. Flame temperature increases with increased Reynolds number for different operating conditions. Effect of Reynolds number on combustion process for light diesel flame is greater than for kerosene flame and also for rich flame is greater than for lean flame. The present work contributes to design and development of lean prevaporized premixed (LPP gas turbine combustors.

  19. Residual deficits in quality of life one year after intensity-modulated radiotherapy for patients with locally advanced head and neck cancer. Results of a prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Tribius, Silke; Raguse, Marieclaire; Voigt, Christian; Petersen, Cordula; Kruell, Andreas [University Medical Center Hamburg-Eppendorf, Department of Radiation Oncology, Hamburg (Germany); Muenscher, Adrian [University Medical Center Hamburg-Eppendorf, Department of Otorhinolaryngology and Head and Neck Surgery, Hamburg (Germany); Groebe, Alexander [University Medical Center Hamburg-Eppendorf, Department of Maxillofacial Surgery, Hamburg (Germany); Bergelt, Corinna [University Medical Center Hamburg-Eppendorf, Department of Medical Psychology, Hamburg (Germany); Singer, Susanne [University Medical Center Mainz, Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), Mainz (Germany)

    2015-03-08

    Patients with locally advanced head and neck cancer (LAHNC) undergo life-changing treatments that can seriously affect quality of life (QoL). This prospective study examined the key QoL domains during the first year after intensity-modulated radiotherapy (IMRT) and identified predictors of these changes in order to improve patient outcomes. A consecutive series of patients with LAHNC completed the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core module (QLQ-C30) and the HNC-specific QLQ-HN35 before (t0) and at the end (t1) of definitive or adjuvant IMRT, then at 6-8 weeks (t2), 6 months (t3), and 1 year (t4) after IMRT. Patients (n = 111) completing questionnaires at all five time points were included (baseline response rate: 99 %; dropout rate between t0 and t4: 5 %). QoL deteriorated in all domains during IMRT and improved slowly during the first year thereafter. Many domains recovered to baseline values after 1 year but problems with smelling and tasting, dry mouth, and sticky saliva remained issues at this time. Increases in problems with sticky saliva were greater after 1 year in patients with definitive versus adjuvant IMRT (F = 3.5, P = 0.05). QoL in patients with LAHNC receiving IMRT takes approximately 1 year to return to baseline; some domains remain compromised after 1 year. Although IMRT aims to maintain function and QoL, patients experience long-term dry mouth and sticky saliva, particularly following definitive IMRT. Patients should be counseled at the start of therapy to reduce disappointment with the pace of recovery. (orig.) [German] Die Therapie von Patienten mit lokal fortgeschrittenen Kopf-Hals-Tumoren (LFKHT) geht mit einschneidenden Veraenderungen einher und beeinflusst die Lebensqualitaet (LQ) erheblich. Diese prospektive Studie untersucht die LQ waehrend des ersten Jahres nach intensitaetsmodulierter Strahlentherapie (IMRT) und hat Praediktoren dieser Veraenderungen herausgearbeitet, um

  20. RTOG's first quality of life study--RTOG 90-20: a phase II trial of external beam radiation with etanidazole for locally advanced prostate cancer

    International Nuclear Information System (INIS)

    Purpose: To assess institutional and patient compliance with quality of life (QL) instruments in RTOG clinical trials. To assess feasibility of using the Functional Assessment Cancer Therapy (FACT), Sexual Adjustment Questionnaire (SAQ), and Changes in Urinary Function (CUF) QL instruments in a prostate clinical trial and to compare patient self-report of symptoms to medical professional ratings of the same symptoms using the RTOG acute toxicity rating scales. Methods and Materials: Three self-assessment QL instruments, the FACT, the SAQ, and CUF, were to be administered to patients on a Phase II locally advanced prostate trial at specified time points. Specific instructions for both data managers and for patients on when, how, and why to fill out the questionnaires were included. Results: Sixty-seven percent (24 out of 36) of patients accrued to RTOG 90-20 completed both the initial FACT and SAQ. Eighty-five percent completed FACT at end of RT and 73% at 3 months. Eighty-one percent completed SAQ at end of treatment, while 69% completed this form at 3 months. Compliance drops off thereafter. Seventy-five percent of patients who had their symptom of dysuria rated by a medical professional as 0 on the RTOG toxicity rating scale self-reported the same. Only 56% of patient self-reports on FACT regarding diarrhea were in agreement with the medical professional's RTOG rating of 0 toxicity. The measures were determined to be in moderate agreement when the patient evaluated a symptom as a 1 on the FACT and the medical professional rated the same symptom as a 0 on the RTOG toxicity rating scale. There was moderate agreement in 13% of patients with dysuria and 31% of patients with diarrhea. Low agreement occurred when the patient evaluated a symptom as a 2 or 3 on the FACT and the medical professional rated the same symptom as a 0 on the RTOG scale. Low agreement occurred in 13% of both patients reporting dysuria and diarrhea. Differences between how medical professionals

  1. Development of a Multi-GeV spectrometer for laser-plasma experiment at FLAME

    International Nuclear Information System (INIS)

    The advance in laser-plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular, the upcoming experiments with the 250 TW laser at the FLAME facility of the INFN Laboratori Nazionali di Frascati, will enter the GeV regime with more than 100 pC of electrons. At the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need for developing a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV), with still unknown angular divergences. Within the PlasmonX experiment at FLAME, a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence, present challenges in the design and construction of such a device. We present the design considerations for this spectrometer that lead to the use of scintillating fibers, multichannel photo-multipliers and a multiplexing electronics, a combination which is innovative in the field. We also present the experimental results obtained with a high intensity electron beam performed on a prototype at the LNF beam test facility.

  2. Development of a Multi-GeV spectrometer for laser-plasma experiment at FLAME

    Science.gov (United States)

    Valente, P.; Anelli, F.; Bacci, A.; Batani, D.; Bellaveglia, M.; Benocci, R.; Benedetti, C.; Cacciotti, L.; Cecchetti, C. A.; Clozza, A.; Cultrera, L.; Di Pirro, G.; Drenska, N.; Faccini, R.; Ferrario, M.; Filippetto, D.; Fioravanti, S.; Gallo, A.; Gamucci, A.; Gatti, G.; Ghigo, A.; Giulietti, A.; Giulietti, D.; Gizzi, L. A.; Koester, P.; Labate, L.; Levato, T.; Lollo, V.; Londrillo, P.; Martellotti, S.; Pace, E.; Pathak, N.; Rossi, A.; Tani, F.; Serafini, L.; Turchetti, G.; Vaccarezza, C.

    2011-10-01

    The advance in laser-plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular, the upcoming experiments with the 250 TW laser at the FLAME facility of the INFN Laboratori Nazionali di Frascati, will enter the GeV regime with more than 100 pC of electrons. At the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need for developing a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV), with still unknown angular divergences. Within the PlasmonX experiment at FLAME, a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence, present challenges in the design and construction of such a device. We present the design considerations for this spectrometer that lead to the use of scintillating fibers, multichannel photo-multipliers and a multiplexing electronics, a combination which is innovative in the field. We also present the experimental results obtained with a high intensity electron beam performed on a prototype at the LNF beam test facility.

  3. Testing of Flame Sprayed Al2O3 Matrix Coatings Containing TiO2

    Directory of Open Access Journals (Sweden)

    Czupryński A.

    2016-09-01

    Full Text Available The paper presents the results of the properties of flame sprayed ceramic coatings using oxide ceramic materials coating of a powdered aluminium oxide (Al2O3 matrix with 3% titanium oxide (TiO2 applied to unalloyed S235JR grade structural steel. A primer consisting of a metallic Ni-Al-Mo based powder has been applied to plates with dimensions of 5×200×300 mm and front surfaces of Ø40×50 mm cylinders. Flame spraying of primer coating was made using a RotoTec 80 torch, and an external coating was made with a CastoDyn DS 8000 torch. Evaluation of the coating properties was conducted using metallographic testing, phase composition research, measurement of microhardness, substrate coating adhesion (acc. to EN 582:1996 standard, erosion wear resistance (acc. to ASTM G76-95 standard, and abrasive wear resistance (acc. to ASTM G65 standard and thermal impact. The testing performed has demonstrated that flame spraying with 97% Al2O3 powder containing 3% TiO2 performed in a range of parameters allows for obtaining high-quality ceramic coatings with thickness up to ca. 500 µm on a steel base. Spray coating possesses a structure consisting mainly of aluminium oxide and a small amount of NiAl10O16 and NiAl32O49 phases. The bonding primer coat sprayed with the Ni-Al-Mo powder to the steel substrate and external coating sprayed with the 97% Al2O3 powder with 3% TiO2 addition demonstrates mechanical bonding characteristics. The coating is characterized by a high adhesion to the base amounting to 6.5 MPa. Average hardness of the external coating is ca. 780 HV. The obtained coatings are characterized by high erosion and abrasive wear resistance and the resistance to effects of cyclic thermal shock.

  4. Response to acoustic forcing of laminar coflow jet diffusion flames

    KAUST Repository

    Chrystie, Robin

    2014-04-23

    Toward the goal of understanding and controlling instability in combustion systems, we present a fundamental characterization of the interaction of the buoyancy-induced instability in flickering flames with forced excitation of fuel supply. Laminar coflow diffusion flames were acoustically forced, whose frequency responses were recorded as a function of excitation frequency and amplitude. The evolving structure of such flames was also examined through the use of video analysis and particle imaging velocimetry (PIV). For specific combinations of excitation frequency and amplitude, the frequency response of the flames was found to couple to that of the forcing, where the contribution of natural puffing frequency disappears. Such instances of coupling exhibited many harmonics of the excitation frequency, related indirectly to the natural puffing frequency. We showed how such harmonics form, through application of PIV, and furthermore unveiled insight into the physics of how the flame couples to the forcing under certain conditions. Our frequency response characterization provides quantitative results, which are of utility for both modeling studies and active-control strategies. Copyright © Taylor & Francis Group, LLC.

  5. Ethanol flame synthesis of carbon nanotubes in deficient oxygen environments

    Science.gov (United States)

    Hu, Wei-Chieh; Lin, Ta-Hui

    2016-04-01

    In this study, carbon nanotubes (CNTs) were synthesized using ethanol diffusion flames in a stagnation-flow system composed of an upper oxidizer duct and a lower liquid pool. In the experiments, a gaseous mixture of oxygen and nitrogen flowed from the upper oxidizer duct, and then impinged onto the vertically aligned ethanol pool to generate a planar and steady diffusion flame in a deficient oxygen environment. A nascent nickel mesh was used as the catalytic metal substrate to collect deposited materials. The effect of low oxygen concentration on the formation of CNTs was explored. The oxygen concentration significantly influenced the flame environment and thus the synthesized carbon products. Lowering the oxygen concentration increased the yield, diameter, and uniformity of CNTs. The optimal operating conditions for CNT synthesis were an oxygen concentration in the range of 15%-19%, a flame temperature in the range of 460 °C-870 °C, and a sampling position of 0.5-1 mm below the upper edge of the blue flame front. It is noteworthy that the concentration gradient of C2 species and CO governed the CNT growth directly. CNTs were successfully fabricated in regions with uniform C2 species and CO distributions.

  6. Synergistic Study on the Effect of Flame Retardants on Timber

    Directory of Open Access Journals (Sweden)

    Nwajiobi, C.C

    2015-12-01

    Full Text Available the fire characteristic proportion of Halleacilliata has been carried out. The timber was treated with different concentrations of ammonium chloride (0.01, 0.05, 0.10, 0.15, 0.50, and 0.55 mol/dm3 and borax (0.01, 0.03, 0.05, 0.07, 0.10, and 0.12 mol/dm3 . Flammability tests such as ignition time, flame propagation rate and after-glow time were carried out and the results showed that the flame retardants drastically reduced the flame propagation rate and after-glow time while ignition time and percentage add-on (% increased. Synergy was observed when the two flame retardants were mixed at different concentrations which gave better retarding properties than when treated individually. These results are interpreted as arising from the fact that on heating, these flame retardants evolve molecules that interfere with the chemistry and pyrolysis of combustion of timber.

  7. Terahertz time-domain spectroscopy of high-pressure flames

    Institute of Scientific and Technical Information of China (English)

    Jason BASSI; Mark STRINGER; Bob MILES; Yang ZHANG

    2009-01-01

    Laser spectroscopy in the visible and near infrared is widely used as a diagnostic tool for combustion devices, but this approach is difficult at high pressures within a sooty flame itself. High soot concentrations render flames opaque to visible light, but they remain transparent to far-infrared or terahertz (THz) radiation. The first far-infrared absorption spectra, to the best of our knowledge, of sooty, non-premixed, ethylene high-pressure flames covering the region of 0.2-2.5 THz is presented. A specially designed high-pressure burner which is optically accessible to THz radiation has been built allowing flame transmission measurements up to pressures of 1.6 MPa. Calculations of the theoretical combustion species absorption spectra in the 0.2-3 THz range have shown that almost all the observable features arise from H2O. A few OH (1.84 and 2.51 THz), CH (2.58 THz), and NH3 (1.77 and 2.95 THz) absorption lines are also observable in principle. A large number of H2O absorption lines are observed in the ground vibrational in a laminar non-premixed, sooty flame (ethylene) at pressures up to 1.6 MPa.

  8. Review of soot measurement in hydrocarbon-air flames

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Soot,which is produced in fuel-rich parts of flames as a result of incomplete combustion of hydrocarbons,is the No.2 contributor to global warming after carbon dioxide.Developing soot measurement techniques is important to understand soot formation mechanism and control soot emission.The various soot measurement techniques,such as thermophoretic sampling par-ticles diagnostics followed by electron microscopy analysis,thermocouple particle densitometry,light extinction,laser-induced incandescence,two-color method,and emission computed tomography,are reviewed in this paper.The measurement principle and application cases of these measurement methods are described in detail.The development trend of soot measurement is to realize the on-line measurement of multi-dimensional distributions of temperature,soot volume fraction,soot particle size and other parameters in hydrocarbon-air flames.Soot measurement techniques suitable for both small flames in laboratories and large-scale flames in industrial combustion devices should be developed.Besides,in some special situations,such as high-pressure,zero gravity and micro-gravity flames,soot measurement also should be provided.

  9. Flame Synthesis of Composite Oxides for Catalytic Applications

    DEFF Research Database (Denmark)

    Jensen, Joakim Reimer

    2002-01-01

    The scope of this work is to investigate flame synthesis of oxides and oxide composites for catalytic applications. Vaporized acetylcetonate precursors are combusted in a flame leading to the formation of metal oxides with high specific surface areas. The employed flame setup is a premixed flat...... the flame temperature, the high temperature residence time and the precursor concentration. The Cu/ZnO/Al2O3 methanol catalyst is used as a model system for the preparation of catalytic materials. The flame synthesized catalyst exhibits a high and reproducible activity for methanol formation from synthesis...... gas (CO/CO2/H2) and an excellent thermal stability. Addition of alumina as a structural promoter is necessary in order to obtain a high activity for methanol formation. The binary systems, i.e., CuO/ZnO, ZnO/Al2O3 and CuO/Al2O3 are investigated as a prelude to the preparation of the ternary catalyst...

  10. Image Quality of 3rd Generation Spiral Cranial Dual-Source CT in Combination with an Advanced Model Iterative Reconstruction Technique: A Prospective Intra-Individual Comparison Study to Standard Sequential Cranial CT Using Identical Radiation Dose.

    Directory of Open Access Journals (Sweden)

    Holger Wenz

    Full Text Available To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT spiral cranial CT (cCT to a sequential 4-slice Multi-Slice-CT (MSCT while maintaining identical intra-individual radiation dose levels.35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was reconstructed using filtered backward projection (FBP and 3rd-generation iterative reconstruction (IR algorithm at 5 different IR strength levels. Two neuroradiologists independently evaluated subjective image quality using a 4-point Likert-scale and objective image quality was assessed in white matter and nucleus caudatus with signal-to-noise ratios (SNR being subsequently calculated.Subjective image quality of all spiral cCT datasets was rated significantly higher compared to the 4-slice MDCT sequential acquisitions (p<0.05. Mean SNR was significantly higher in all spiral compared to sequential cCT datasets with mean SNR improvement of 61.65% (p*Bonferroni0.05<0.0024. Subjective image quality improved with increasing IR levels.Combination of 3rd-generation DSCT spiral cCT with an advanced model IR technique significantly improves subjective and objective image quality compared to a standard sequential cCT acquisition acquired at identical dose levels.

  11. Effect of CH4–Air Ratios on Gas Explosion Flame Microstructure and Propagation Behaviors

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    2012-10-01

    Full Text Available To reveal the inner mechanism of gas explosion dynamic behavior affected by gas equivalent concentration, a high speed Schlieren image system and flow field measurement technology was applied to record the gas explosion flame propagation and flame structure transition. The results show that a flame front structure transition occurs, followed by a flame accelerating propagation process. The laminar to turbulence transition was the essential cause of the flame structure changes. The laminar flame propagation behavior was influenced mainly by gas expansion and fore-compressive wave effect, while the turbulent flame speed mostly depended on turbulence intensity, which also played an important role in peak value of the explosive pressure and flame speed. On the condition that the laminar-turbulent transition was easier to form, the conclusion was drawn that, the lowest CH4 concentration for maximum overpressure can be obtained, which was the essential reason why the ideal explosive concentration differs under different test conditions.

  12. Analysis of Reaction-Diffusion Systems for Flame Capturing in Type Ia Supernova Simulations

    CERN Document Server

    Zhiglo, Andrey V

    2009-01-01

    We present a study of numerical behavior of a thickened flame used in Flame Capturing (FC, Khokhlov (1995)) for tracking thin unresolved physical flames in deflagration simulations. We develop a steady-state procedure for calibrating the flame model used, and test it against analytical results. We observe numerical noises generated by original realization of the technique. Alternative artificial burning rates are discussed, which produce acceptably quiet flames. Two new quiet models are calibrated to yield required "flame" speed and width, and further studied in 2D and 3D setting. Landau-Darrieus type instabilities of the flames are observed. One model also shows significantly anisotropic propagation speed on the grid, both effects increasingly pronounced at larger matter expansion as a result of burning; this makes the model unacceptable for use in type Ia supernova simulations. Another model looks promising for use in flame capturing at fuel to ash density ratio of order 3 and below. That "Model B" yields f...

  13. Study of the mechanisms of the flame propagation and stabilization in porous media

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The CH4/air premixed gas combustion processes in porous media were numerically studied using the two-temperature reacting fluid model with dispersions and detailed chemical reaction mechanism GRI 3.0. The mechanisms of the propagation and stabilization of submerge flames and surface flames in porous media were illuminated distinctly by considering the magnitude of the terms in the two energy equations, analyzing the sensibility of flame propagation speed to flame location, heat exchange coefficient between gas and solid, thermal conductivity and radiative extinction coefficient of porous media. It was concluded that the propagation mechanism of a submerged flame is similar to that of a free flame with an additional preheat zone and that the surface-flame propagation mechanism in porous media is similar to that of a free flame with heat loss in reaction zone.

  14. Preflame zone structure and main features of fuel conversion in atmospheric pressure premixed laminar hydrocarbon flames

    Energy Technology Data Exchange (ETDEWEB)

    Ksandopulo, G.I.

    1995-08-25

    This report describes the structure study of the premixed hydrocarbon-oxidizer Bunsen flames burning at the atmospheric pressure and also the ones with some inhibitors added. Studies were performed on hexane, propane, methane, acetylene, and hexene flames.

  15. Study of the mechanisms of the flame propagation and stabilization in porous media

    Institute of Scientific and Technical Information of China (English)

    ZHAO PingHui; YE TaoHong; JIANG Hal; CHEN YiLiang

    2008-01-01

    The CH4/air premixed gas combustion processes in porous media were numeri-cally studied using the two-temperature reacting fluid model with dispersions and detailed chemical reaction mechanism GRI 3.0.The mechanisms of the propagation and stabilization of submerge flames and surface flames in porous media were illuminated distinctly by considering the magnitude of the terms in the two energy equations,analyzing the sensibility of flame propagation speed to flame location,heat exchange coefficient between gas and solid,thermal conductivity and radia-tive extinction coefficient of porous media.It was concluded that the propagation mechanism of a submerged flame is similar to that of a free flame with an additional preheat zone and that the surface-flame propagation mechanism in porous media is similar to that of a free flame with heat loss in reaction zone.

  16. Instabilities and soot formation in spherically expanding, high pressure, rich, iso-octane-air flames

    Energy Technology Data Exchange (ETDEWEB)

    Lockett, R D [School of Engineering and Mathematical Sciences, City University, Northampton Square, London EC1V OHB (United Kingdom)

    2006-07-15

    Flame instabilities, cellular structures and soot formed in high pressure, rich, spherically expanding iso-octane-air flames have been studied experimentally using high speed Schlieren cinematography, OH fluorescence, Mie scattering and laser induced incandescence. Cellular structures with two wavelength ranges developed on the flame surface. The larger wavelength cellular structure was produced by the Landau-Darrieus hydrodynamic instability, while the short wavelength cellular structure was produced by the thermal-diffusive instability. Large negative curvature in the short wavelength cusps caused local flame quenching and fracture of the flame surface. In rich flames with equivalence ratio {phi} > 1.8, soot was formed in a honeycomb-like structure behind flame cracks associated with the large wavelength cellular structure induced by the hydrodynamic instability. The formation of soot precursors through low temperature pyrolysis was suggested as a suitable mechanism for the initiation of soot formation behind the large wavelength flame cracks.

  17. Environmental monitoring of brominated flame retardants

    Science.gov (United States)

    Vagula, Mary C.; Kubeldis, Nathan; Nelatury, Charles F.

    2011-06-01

    Brominated flame retardants (BFRs) are synthetic organobromide compounds which inhibit ignition and combustion processes. Because of their immense ability to retard fire and save life and property, they have been extensively used in many products such as TVs, computers, foam, plastics etc. The five major classes of BFRs are tetrabromobisphenol-A (TBBPA), hexabromocyclododecane (HBCD), pentabromodiphenyl ether, octabromodiphenyl ether, and decabromodiphenyl ether. The last three are also commonly called PBDEs. BDE-85 and BDE-209 are the two prominent congeners of PBDEs and this study reports the adverse effects of these congeners in rodents. Exposure of rat sciatic nerves to 5 μg/mL and 20 μg/mL of BDE-85 and BDE-209 respectively lead to significant, concentration dependent reduction in nerve conduction function. Glucose absorption in the rat intestinal segments exposed to 5 μg/mL of BDE-85 and BDE-209 was significantly reduced for both the compounds tested. Lastly, mice when exposed to 0.25 mg/kg body weight for four days showed a disruption in oxidant and antioxidant equilibrium. The tissues namely liver and brain have shown increase in the levels of lipid hydroperoxides indicating oxidative stress. Moreover, all the protective enzymes namely superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, and glutathione S transferase (GST) have shown tissue specific alterations indicating the induction of damaging oxidative stress and setting in of lipid peroxidation in exposed animals. The results indicate monitoring of PBDEs in the environment is essential because levels as low as 5 μg/mL and 0.25 mg/kg body weight were able to cause damage to the functions of rodents.

  18. Effects of AC Electric Field on Small Laminar Nonpremixed Flames

    KAUST Repository

    Xiong, Yuan

    2015-04-01

    Electric field can be a viable method in controlling various combustion properties. Comparing to traditional actuators, an application of electric field requires very small power consumption. Especially, alternating current (AC) has received attention recently, since it could modulate flames appreciably even for the cases when direct current (DC) has minimal effects. In this study, the effect of AC electric fields on small coflow diffusion flames is focused with applications of various laser diagnostic techniques. Flow characteristics of baseline diffusion flames, which corresponds to stationary small coflow diffusion flames when electric field is not applied, were firstly investigated with a particular focus on the flow field in near-nozzle region with the buoyancy force exerted on fuels due to density differences among fuel, ambient air, and burnt gas. The result showed that the buoyancy force exerted on the fuel as well as on burnt gas significantly distorted the near-nozzle flow-fields. In the fuels with densities heavier than air, recirculation zones were formed very close to the nozzle exit. Nozzle heating effect influenced this near-nozzle flow-field particularly among lighter fuels. Numerical simulations were also conducted and the results showed that a fuel inlet boundary condition with a fully developed velocity profile for cases with long fuel tubes should be specified inside the fuel tube to obtain satisfactory agreement in both the flow and temperature fields with those from experiment. With sub-critical AC applied to the baseline flames, particle image velocimetry (PIV), light scattering, laser-induced incandescence (LII), and laser-induced fluores- cence (LIF) techniques were adopted to identify the flow field and the structures of OH, polycyclic aromatic hydrocarbons (PAHs), soot zone. Under certain AC condi- tions of applied voltage and frequency, the distribution of PAHs and the flow field near the nozzle exit were drastically altered from the

  19. Laser Soot-Scattering Imaging of a Large Buoyant Diffusion Flame

    OpenAIRE

    Miake-Lye, Richard C.; Toner, Stephen J.

    1987-01-01

    A novel diagnostic technique, which makes use of laser light scattered by soot particles, was used in an effort to identify the flame sheets within a natural gas diffusion flame. Soot particles, inherently created and consumed in the flame, were used as the scattering medium, which obviated the need for externally supplied seed material. Since no foreign material was added to the flame, the current technique can be considered truly nonintrusive. The soot distribution within a large buoyant...

  20. Quantitative Assessment of Flame Stability Through Image Processing and Spectral Analysis

    OpenAIRE

    Sun, Duo; Lu, Gang; Zhou, Hao; Yan, Yong; Liu, Shi

    2015-01-01

    This paper experimentally investigates two generalized methods, i.e., a simple universal index and oscillation frequency, for the quantitative assessment of flame stability at fossil-fuel-fired furnaces. The index is proposed to assess the stability of flame in terms of its color, geometry, and luminance. It is designed by combining up to seven characteristic parameters extracted from flame images. The oscillation frequency is derived from the spectral analysis of flame radiation signals. The...