In the thermal hydraulics codes developed for fire safety analysis and for containment thermal hydraulic analysis, junctions in the multi-compartment geometries is often modeled as uni-directional junctions. However, ceiling junctions are known to depict unstable/oscillatory bi-directional flow behavior. Detailed investigations have been carried out to understand the unstable flow behaviour of a junction by analyzing an earlier reported experiment and its subsequent two dimensional numerical RANS based study of fire in an enclosure. The authors attempt more realistic and desired three dimensional and inherently transient large eddy simulations using a computer code Fire Dynamics Simulator (FDS). The paper presents the details of the analysis, the results obtained and further studies required to be conducted so that the findings can be applied to the fire/containment thermal ...
Full text of publication follows: General simulation objectives of any fire analysis are macroscopic in nature and deals with the grass data in respect of fire/smoke spread, structural behaviour, environmental conditions etc. However, the accuracy of predicting such macroscopic parameters is a strong function of several other microscopic parameters which govern the overall macroscopic behaviour. Some of the microscopic parameters of interesting such analysis could be buoyancy induced stable/unstable flows, relative flame behaviour, baroclinic velocity distribution etc. Only the field based fire modelling approach is capable of calculating several of these by way of detailed CFD based field modelling. One of the best known tool that could be employed for such studies is the Fire Dynamics simulator (FDS) from NIST with its popular LES based ...
With the frequent load changes to which a hard coal power station is subjected in the middle and peak load range, great demands are linked with the transient behaviour of the steam generator. Due to the serial connection of the crusher and boiler, the strongly delaying transient behaviour of the crusher compounds entirely with the transient behaviour of the steam generator. Therefore, a suggestion is to be made here as to the improvement of the dynamics of the crusher.
ii) Flammability: (iii) A capacity to oxidise: (iv) Corrosiveness: (v) Toxicity (including chronic ...an explosion or fire: (d) For substances with corrosive properties: (i) To reduce the ...likelihood of any unintended corrosion:(ii) To control the adverse effects of any corrosion:
Apart from the vulnerability implied by the START II treaty, it will bear the burden of the general political opposition to the Yeltsin administration. START II will be seen as part of an overall Yeltsin-Andrei Kozyrev foreign policy that is under fire for selling out Russian national interests in Yugoslavia, the Persian Gulf, and elsewhere. This article discusses public opinion concerning START II, the cost of its implementation, and the general purpose of the treaty.
A study was conducted to predict indoor ventilation, smoke movement and fire propagation in a new building currently under construction at the Ecole Polytechnique de Montreal. It was conducted in response to concerns regarding the impact that air quality, in normal operation conditions, and smoke concentration, in the event of a fire, may have on occupants of a building. A detailed three-dimensional model of the new building was constructed using the NURBS-based modeler, Rhino. Simulations of fire propagation and airflow ventilation were performed in different areas of the building. The flow pattern data was analyzed using the computational fluid dynamics (CFD) program called FLUENT. It predicted air flow conditions and estimated the mean age of air (MAA) in the room. Real-world geometries, such as diffuser inlets, have a significant impact on overall fluid flow behaviour and are necessary for this type ...
The Oxycoal burner for pulverised coal combustion previously developed by the authors has been scaled up to typical power plant dimensions and a CFD study of pulverised coal combustion in a 1200 MWth oxy-firing furnace has been performed. The study revealed the importance of modelling the flue gas radiation behaviour for flue gas temperatures and wall heat transfer. This was done using a non-grey implementation of the Exponential Wide Band Model (EWBM). Typically, comparisons between air and oxy-fired furnaces point out that to obtain similar flame behaviour, the oxygen content in oxy-firing conditions should be increased until the same adiabatic flame temperature is reached. However, it was found that for these conditions, significantly increased wall heat fluxes can be the result. Furthermore, at gas temperatures comparable to air combustion, particle burnout is accelerated in ...
Liquid sodium is used as coolant in Fast Breeder Reactors (FBR). There is a likelyhood of sodium spillage in ambient air in the Steam Generator Building (SGB) of the FBR plant. Due to high chemical reactivity with oxygen, especially at temperatures greater than 573 K, it catches fire very easily. In order to carryout safety related experimental studies for different modes of sodium fires and to develop suitable mathematical models for the assessment of their consequences, an experimental facility (SFEF, Sodium Fire Experimental Facility) is being setup a IGCAR, Kalpakkam. The SFEF is having a 540 m"3 volume experimental hall. Stainless steel linear will be provided on the inside surfaces of experimental hall walls, ceiling and floor. Analysis has been carried out for enclosed sodium pool fire scenarios in SFEF by using sodium pool fire code SOFIRE II, which ...
In most industrial processes operating at elevated temperatures, protective oxide layers perform a vital duty in protecting the underlying metallic alloys from process gases. Coal-fired combined cycle power generation systems present a number of process conditions in which the properties of the protective oxide layers are particularly important. This paper discusses two of these particular conditions: (1) `erosion/corrosion` of in-bed heat exchanger tubing and (2) thermal cycling of hot gas path components. For both these situations, the desirable properties of protective scales are outlined. The behaviour of scales in practice are highlighted. 33 refs., 6 figs., 2 tabs.
Probabilistic assessment methods can be used to identify specific plant vulnerabilities. Application of such methods can also facilitate selection among system design alternatives available for safety enhancements. The quality of assessment results is however strongly dependent on realistic and accurate input data for modelling of system component behaviour and failure modes during conditions to be assessed. Use of conservative input data may not lead to results providing guidance on safety upgrades. Adequate input data for probabilistic assessments seems to be lacking for at least failure modes of some electrical components when exposed to a fire. This report presents an attempt to improve the situation with respect to such input data. In order to take advantage of information in existing documentation of fire incident occurrences some of the lessons learned from the fire at Browns Ferry Nuclear Power ...
Experimental results are presented on the quasi-statistic polarization reversal and on the effect of high dc electric field on the behaviour of LiNH_4SO_4 and LiND_4SO_4 monocrystals, namely in the vicinity of the II-III phase transformation.
High temperature deformation behaviour of an experimental Beta-titanium alloy Ti-10V has been studied in the temperature range 800 to 945 degree C by using the method of crosshead speed cycling. Although subgrain formation was observed but the alloy did not exhibit superplastic behaviour in the entire temperature range studied. A very large initial grain size and elongation of grains during the deformation are considered the main factors responsible for absence of superplastic behaviour. The activation energy values for regions II and III of the ln sigma vs. ln small epsilon plots are close to the lower of the two activation energy values proposed together to describe self diffusion in beta-phase suggesting that the rate controlling mechanism is that for lattice diffusion rather then grain boundary diffusion. (author)
Heat exchangers for high and ultrahigh temperatures are a need and a precondition to realise high efficient fossil fired power plants based on the so-called Externally Fired Combined Cycle (EFCC) or the Indirect Fired Gas Turbines (IFGT). The main target of both processes is to increase the thermal efficiency of existing power plants by approximately 25% resulting in the same decrease in fuel consumption and, therefore, in the same reduction of CO{sub 2} formation. The main activities of the MPA University of Stuttgart in this project is focused on the characterisation and qualification of the structural material of the ultrahigh temperature heat exchanger (UHTHE) necessary in the above mentioned processes. The influence of the temperature and load on the material behaviour have been analysed by means of tensile tests and creep tests. The effectiveness of different coating systems and the interaction ...
The availability of technology for reducing SO2 emissions from coal-fired steam generators using flue gas desulfurization (FGD) systems is discussed. Foreign and domestic lime, limestone, double alkali, magnesium slurry, and Wellman-Lord FGD systems are described, and the design parameters and operating experiences are discussed. Steps that have been taken to achieve high system operability are discussed. Also, disposal of FGD system wastes is discussed briefly.
This paper proposes an integrated method for using experimental data and CFD modeling to develop engineering correlations for atrium smoke management. Part I focused on the experimental program and validation of a CFD model of the experimental facility. Part II describes the extension of this model to a parametric study of balcony spill plumes. Smoke management in buildings during fire events often uses mechanical ventilation systems to maintain smoke layer elevation above a safe evacuation path. Design of these systems requires accurate correlations for the smoke production or mass flow rate of the buoyant fire plume. One design issue is the mass flow rate of fire plumes which spill out from a fire compartment, under a balcony and up through an atrium or other large volume. Current engineering correlations for these balcony spill plumes (BSPs) are based on a combination of ...
This paper proposes an integrated method for using experimental data and CFD modeling to develop engineering correlations for atrium smoke management. Part I focused on the experimental program and validation of a CFD model of the experimental facility. Part II describes the extension of this model to a parametric study of balcony spill plumes. Smoke management in buildings during fire events often uses mechanical ventilation systems to maintain smoke layer elevation above a safe evacuation path. Design of these systems requires accurate correlations for the smoke production or mass flow rate of the buoyant fire plume. One design issue is the mass flow rate of fire plumes which spill out from a fire compartment, under a balcony and up through an atrium or other large volume. Current engineering correlations for these balcony spill plumes (BSPs) are based on a combination of ...
Given that fossil fuel fired power plants are among the largest and most concentrated producers of CO{sub 2} emissions, recovery and sequestration of CO{sub 2} from the flue gas of such plants has been identified as one of the primary means for reducing anthropogenic CO{sub 2} emissions. In this study, ALSTOM Power Inc. (ALSTOM) has investigated several coal fired power plant configurations designed to capture CO{sub 2} from effluent gas streams for use or sequestration. Burning fossil fuels in mixtures of oxygen and recirculated flue gas (made principally of CO{sub 2}) essentially eliminates the presence of atmospheric nitrogen in the flue gas. The resulting flue gas is comprised primarily of CO{sub 2}. Oxygen firing in utility scale Pulverized Coal (PC) fired boilers has been shown to be a more economical method for CO{sub 2} capture than amine scrubbing (Bozzuto, et al., 2001). Additionally, oxygen ...
The design of a solar heated cavity receiver transferring 60 MW of thermal energy to the working medium (air) for a closed-cycle gas turbine is described. The gas turbine plant with its cycle layout is presented. Then the tubes for the receiver are designed taking into account thermal and mechanical loads. It is shown how the occurring stresses are influenced by the destribution of the locally absorbed hat flux. Calculations for an existing coal fired air heater of a closed-cycle gas turbine give a first impression of the long-term behaviour to be expected of the receiver tubes.
A comparative study by Eu-L/sub III/ X-ray absorption and /sup 151/Eu-Moessbauer spectroscopy is presented for the EuPd/sub 2-x/Au/sub x/ Si/sub 2/ series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L/sub II /I-edge spectra are discussed.
The report gives results of an analysis of the effect of the availability of a flue gas desulfurization system on the ability of an individual power plant to generate electricity at its rated capacity. (The availability of anything is the fraction of time it is capable of service, whether or not it is actually in service.) Also analyzed are its effects on a power generating system (a group of several coal-, oil-, and gas- fired power plants plus nuclear and hydroelectric plants).
Crystalline bis(O,O'-di-sec-butyldithiophosphato)platinum(II) was prepared and studied by means of 13C, 31P CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the platinum(II) compound is comprised of one centrosymmetric mononuclear molecule [Pt{S2P(O-sec-C4H9)2}2], in which the dithiophosphate groups display structural equivalence in both 31P NMR and XRD data. A pair of the dithiophosphate ligands exhibit the same S,S'-bidentate chelating structural function and form two planar four-membered chelate rings, [PtS2P], in this molecule. The planar configuration of the [PtS4] chromophore in structure 1 is governed by the dsp2-hybrid state of platinum(II). The structural states of the dithiophosphate groups in two different samples of complex 1 (one crystallised from...
The potential of the dried yeast, wild-type Schizosaccharomyces pombe, to remove Ni(II) ion was investigated in batch mode under varying experimental conditions including pH, temperature, initial metal ion concentration and biosorbent dose. Optimum pH for biosorption was determined as 5.0. The highest equilibrium uptake of Ni(II) on S. pombe, q e, was obtained at 25??C as 33.8?mg?g?1. It decreased with increasing temperature within a range of 25?50??C denoting an exothermic behaviour. Increasing initial Ni(II) concentration up to 400?mg?L?1 also elevated equilibrium uptake. No more adsorption took place beyond 400?mg?L?1. Equilibrium data fitted better to Langmuir model rather than Freundlich model. Sips, Redlich?Peterson, and Kahn isotherm equations modelled the investigated system with a...
Selected local woods and their wood-polymer combinations or composites (WPC) were tested for their thermal conductivity and their fire resistance. WPC were prepared by polymerizing monomers ''in situ'' in oven dried woods by gamma radiation. The monomers included acrylonitrile (AN), 60% styrene-40% acrylonitrile (STAN), methyl methacrylate (MMA), 95% methyl methacrylate-5% dioxane (MD), and vinylidene chloride (VDC). A reduction in thermal conductivity was exhibited by all the composites prepared. W-PAN showed the greatest reduction in thermal conductivity and W-PSTAN in general showed the least. An explanation is suggested for this behaviour. The polymers PMMA and PMD were found to enhance flammability of the woods while PVDC, PAN, and PSTAN imparted fire resistance to the woods. Of the six local woods studied, Ramin-and-Keruing-polymer composites showed the highest flammable tendencies ...
During the last 15 years cycles with CO{sub 2} capture have been in focus, due to the growing concern over our climate. Often, a natural gas fired combined cycle with a chemical absorption plant for CO{sub 2} capture from the flue gases have been used as a reference in comparisons between cycles. Neither the integration of the steam production for regeneration of amines in the combined cycle nor the off-design behaviour of such a plant has been extensively studied before. In this paper, the integration of steam production for regeneration of the amines is modelled at design load and studied in off-design conditions for a combined cycle. Different ambient conditions and part-load strategies and their influence on the cycle performance are also examined. Of particular interest is a novel strategy with the possibility of longer life of gas turbine blading, with marginal loss in efficiency. The off-design performance of the combined cycle is ...
The electrochemical behaviour of passive films formed on one austenitic stainless steel (AISI 304) and one ferritic stainless steel (AISI 446) in solutions with pH between 0.6 and 8.4 was studied by capacitance measurements and photocurrent spectroscopy. Compositional characterization of the passive films was done by X-ray photoelectron spectroscopy. The capacitance increases with decreasing pH. Doping densities evaluated from Mott-Schottky plots are in the range 2-6 x 10{sup 20} cm{sup -3} and increased with the pH in the neutral/alkaline range while in pH 0.6, values above 10{sup 21} cm{sup -3} were found. The bandgap energy indicates two transitions, at 2.5-2.8 and 3.2 eV. The analytical data reveal that, as the pH increased, the films become enriched in Fe(II) and Fe(III), whereas the Cr(III) gradually decreases. The films formed at very low pH had a behaviour that contrasts with that of the films formed in the ...
The electrochemical behaviour of passive films formed on one austenitic stainless steel (AISI 304) and one ferritic stainless steel (AISI 446) in solutions with pH between 0.6 and 8.4 was studied by capacitance measurements and photocurrent spectroscopy. Compositional characterization of the passive films was done by X-ray photoelectron spectroscopy. The capacitance increases with decreasing pH. Doping densities evaluated from Mott-Schottky plots are in the range 2-6 x 10"2"0 cm"-"3 and increased with the pH in the neutral/alkaline range while in pH 0.6, values above 10"2"1 cm"-"3 were found. The bandgap energy indicates two transitions, at 2.5-2.8 and 3.2 eV. The analytical data reveal that, as the pH increased, the films become enriched in Fe(II) and Fe(III), whereas the Cr(III) gradually decreases. The films formed at very low pH had a behaviour that contrasts with that of the films formed in the neutral/alkaline media. ...
The results of the thermo-hydro-mechanical (THM) study of the FEBEX bentonite performed during FEBEX II are presented. The laboratory test program continued in part with the works carried out during FEBEX I, particularly in activities related to tests aimed to the calibration of the models, the acquisition of parameters by back-analysis and the improvement of the knowledge on the behaviour of expansive clays. But the program has also included tests on new areas: investigations about the influence of the microstructure changes in bentonite, of temperature and of the solute concentration on the behaviour of clay. Besides, several tests were proposed in order to understand the unexpected behaviour observed in the mock-up test, towards the end of year 2. Temperature effects on water retention curves in confined and unconfined conditions were determined, and swelling pressure, hydraulic conductivity and ...
Five fires that occurred in the air and gas treatment systems of U.S. commercial nuclear power plants are reviewed. The causes of the fires, the method of extinguishing them and possible fire prevention methods are correlated with the properties of the adsorbents. The similarities and differences of adsorbent (carbon) fires of solvent recovery systems and the nuclear air-cleaning units are discussed in relation to fire development, consequences of the fire, and fire extinguishing methods. The latest methodology of fire prevention, as proposed for a New Hampshire nuclear power plant is described.
Any student that has spent time in the kitchen knows that hot vegetable oil will pop and spatter violently after coming into contact with water such as that on the surface of foods (meat, fish, potatoes, etc.). This well-known effect can be used as an instructional resource to promote cooperative, active, and inquiry-based learning about central concepts of chemistry including boiling point, miscibility, and density of liquids. The starting point of the learning activity is a demonstration of (i) the effect of adding a drop of water to hot (as for cooking) vegetable oil and (ii) the effect of adding a drop of vegetable oil to hot water (near its boiling point). Intermolecular interactions, properties of vegetable oils, and a variety of other topics, such as the importance of other heat points (smoke, flash, and fire) for oils, the fundamental of the crackle test for checking the presence of water in oil, and why an oil fire ...
Work on this coke oven gas cleaning demonstration project (CCT-II) this quarter has been focused on Phase IIB tasks, and include engineering, procurement, construction, and training. Additionally, plans for changes in the operating schedule of the coke plant that affect the demonstration project are described. Engineering efforts are nearly complete. Remaining to be finalized is an assessment of electrical heat tracing/insulation needs for pipe lines, assessment of fire protection requirements, and instrument modifications. Procurement of all major equipment items is complete, except for possible additions to fire fighting capabilities. Major focus is on expediting pipe and structural steel to the project site. Civil construction is complete except for minor pads and bases as required for pipe supports, etc. Erection of the hydrogen sulfide and ammonia scrubber vessels is complete. Installation of scrubber vessel internals ...
Coal fired combined cycle power systems will be a sufficient way to increase the efficiency of coal combustion. However, combined cycle power systems require a reliable hot gas cleanup. Especially alkali metals, such as sodium and potassium, can lead to hot corrosion of the gas turbine blading if they condensate as sulphates. The actual work deals with the release and sorption of alkali metals in coal fired combined cycle power systems. The influence of coal composition, temperature and pressure on the release of alkali species in coal combustion was investigated and the relevant release mechanisms identified. Alumosilicate sorbents have been found that reduce the alkali concentration in the hot flue gas of the Circulating Pressurized Fluidized Bed Combustion 2{sup nd} Generation (CPFBC 2{sup nd} Gen.) at 750 C to values sufficient for use in a gas turbine. Accordingly, alumosilicate sorbents working at 1400 C have been found for the ...
Mine rescue teams frequently must fight fires and guard against the propagation of fires or explosions during a rescue and recovery operation. The team's ability to fight fires depends a great deal on hands-on experience with different fire fighting agents and equipment. The team's work includes an assessment of fire conditions, mine fire gases and other potential hazards associated with fire fighting activity. This training module covers the underlying principles of the fire triangle and the different methods for controlling, containing and extinguishing fires in a mine. The manual also covers fire-fighting equipment, considerations involved in a sealing operation and the cause-effect of explosions.
of the familiar fire triangle, namely, fuel, ignition, and oxygen. Fuel is minimized ... The third element of the fire triangle, oxygen, is obviously ...
This paper discusses the application of a Computational Fluid Dynamics (CFD) code (FLUENT) to predict temperature and velocity profiles, and particle trajectories in an industrial fired by a low NO{sub x} pulverized coal swirl burner. The predictions of the code were compared to experimental measurements of gas temperature, particle size distribution, and particle velocities. The diagnostics employed were a suction pyrometer and a Particle Counter Sizer Velocimeter Probe (PCSV-P). Good agreement was found between the temperature predictions and the measurements. In situ particle size distributions were predicted accurately using the Baum and Street model with a swelling factor of zero. The numerical modeling indicated that the Type II flow issued from the burner could be transformed into Type III flow, by eliminating swirl from the primary air stream, which provided the preferred particle trajectories and increased the combustion efficiency.
The integrity of the cables located in the target room is very important in the Fire PSA, because the CDF and CCDP are changed according to the results of a cable integrity that depends on the surrounding gas temperature. The conservative assumptions used in the Fire PSA typically specify that all of the equipment and cables of a room would fail when a fire happens in the room. But the realistic assessment of a fire risk by using a fire simulation tool has become necessary in the Fire PSA as described in the ANS Fire PRA Standard. This paper evaluates the cable integrity of eight pump rooms in the nuclear power plant by using the CFAST zone fire model. The upper layer gas temperature of each room is estimated, and an analysis based on the results of model simulations is used to judge the cable integrity. According to the ...
Nomographs that calculate the threshold values of surface fire parameters which lead to crown fire initiation were created by linking two separate fire behavior models: Van Wagner?s crown fire ignition criteria and Byram?s surface fire model. The nomographs were also based on the existing surface (fuel load, fuel heat content) and canopy (foliar moisture content, live crown base height) fuel models of Aleppo (Pinus halepensis Mill.) pine forests of Mediterranean Greece. The most important fire parameters for crown fire initiation that are calculated by the nomographs are the critical flame length and the forward spread rate of the surface fire. These parameters are readily observable in the field during fires. The nomographs provide a judicious way to assess whether a crown fire ...
Since 1976, the Nuclear Engineering Laboratory of the Technical Research Centre of Finland and Lappeenranta University of Technology have cooperated in the field of nuclear reactor thermal-hydraulics. During these years, a series of experimental facilities (REWET-I, -II, -III, VEERA) simulating pressurized water reactors (PWRs) have been built. The newest facility, PACTEL (Parallel Channel Test Loop), is an experimental out-of-pile facility designed to simulate the major components and system behaviour of a commercial PWR during postulated small and medium size break loss-of-coolant accidents (LOCAs), natural circulation and operational transients. A PACTEL natural circulation experiment has been carried out as an OECD/NEA international standard problem ISP 33. (2 refs., 3 figs., 2 tabs.).
Villarrica (Chile) is one of the most active volcanoes in South America having erupted about 60 times in the last 460years. Although its historical eruptive activity has been mainly effusive and weakly explosive, it had strong explosive behaviour in postglacial times. Chaimilla (<3.1ka) is one of the best exposed and widely dispersed pyroclastic deposits, related to both fall and flow activity. The deposit is dispersed over an area of 250km^2 and consists of 8 units (A-H) which were grouped into four sequences. Stratigraphic data suggest that the eruption had a relatively short duration and evolved from i) an Opening phase, dispersing ash, lapilli clasts, accretionary lapilli, blocks and bombs, to ii) a Pulsatory phase, originating a series of magmatic explosions, to iii) a Collapsing phas...
In coke-oven operations flue-gas valves are used to switch the regenerator function from rich gas firing to lean gas firing. Compared with the simple geometry of the other parts of the flow path, which comprise flues and regenerators, the narrow and winding passages of the flue-gas valves give rise to relatively high losses in pressure. Without the construction of high (and therefore expensive) chimneys, this means that operating problems may well arise due the inadequate suction capacity. The project focused on the theoretical and experimental analysis of a coke-oven flue-gas valve. The primary aim was to reduce the pressure drop through the valve without modifying its external geomerty. The internal flow characteristics created by different valve geometries under a variety of operating conditions were simulated using the commercial CFD code Fluent/UNS, which provided velocity and pressure distributions. A half-scale model valve was ...
The integrity of the cables located in the target room is very important in the Fire PSA, because the CDF and CCDP are changed according to the results of a cable integrity that depends on the surrounding gas temperature. The conservative assumptions used in the Fire PSA typically specify that all of the equipment and cables of a room would fail when a fire happens in the room. But the realistic assessment of a fire risk by using a fire simulation tool has become necessary in the Fire PSA as described in the ANS Fire PRA Standard. This paper evaluates the cable integrity of eight pump rooms in the nuclear power plant by using the CFAST zone fire model. The upper layer gas temperature of each room is estimated, and an analysis based on the results of model simulations is used to judge the c...
Surgical fires--fires that occur on or in a surgical patient--are a rare but devastating complication of surgical procedures. They can happen during almost any kind of operation and can have dire consequences for both the patient and the hospital. The risk of surgical fires can be minimized as long as everyone on the surgical team understands how fires start and what to do when they occur. It's important to recognize the interaction among ignition sources, oxidizers, and fuels--the three sides of the classic fire triangle. What's more, staff members need to be alert to "hidden" fire risks, such as unsuspected oxygen-enriched atmospheres and less-than-obvious fuels. They also need to be drilled in the correct steps for responding to fires. In this guide, we describe the elements of surgical fires, including the types of equipment and ...
The work reported is to evaluate two alternative resource recovery systems which would produce a fuel or an energy product (steam) for sale to an industrial plant. The first alternative is a refuse derived fuel (RDF) production facility which would process waste to produce fuel for sale to the plant. The RDF would be co-fired with coal in new boilers. The second alternative is a mass burn steam generation facility which would produce high pressure superheated steam for sale. The steam would be used by the plant to cogenerate electricity and for the process. Conceptual designs are developed for each alternative to form the basis of estimates of capital and operating costs and potential energy revenues. Operating requirements are developed for both alternatives. An assessment is made of the impact of both alternatives on the environment, and it is concluded that the impact of either alternative will be negligible. Order of magnitude estimates are made of capital and ...
... for duty as Naval Gunfire Liaison Officers in Marine Corps Divisions. ... Regiment, the 82nd Airborne Division, the 101st Airborne Division (Air Assault ...
Brush fires, especially during the summer months, are hazards that occasionally threaten the leeward (Waianae) coast of Oahu in Hawaii. The prediction of future ... ...
familiarity fire triangle (i.e., fuel, oxidant, and ignition source) are excluded. It Is obvious that for the baseline safety goal for spacecraft this ...
Fire-driven deforestation is the major source of carbon emissions from Amazonia. Recent expansion of mechanized agriculture in forested regions of Amazonia ...
The VE (ventilation) test carried out at the Mont Terri underground laboratory in Switzerland intended to evaluate in situ the behaviour of a consolidated clay formation when subjected to alternate periods of flow of wet and dry air during several months. For that, a 10-m gallery was excavated in the Opalinus Clay formation and carefully instrumented. Before and after a second ventilation phase boreholes were drilled. Samples were taken from the drill cores and were analysed from mineralogical and geochemical points of view. Also, the retention curves of these samples were determined in the laboratory following drying paths performed under free volume conditions at 20 degree centigrade, what is the content of this report. Although there are not large differences in the WRC of samples taken from different boreholes, at different distances from the gallery wall or before or after ventilation, those samples taken near the gallery wall and after ventilation tend to ...
Susceptibility data of freshly precipitated nitroprussides TM[Fe(CN){sub 5}NO] n H{sub 2}O (TM=Mn, Fe, Co, Ni, Cu) follow very well modified Curie-Weiss law down to T=5 K indicating paramagnetic state; nitroprusside (NP) containing Zn is diamagnetic with a sign of paramagnetic contribution. Deviation from Curie-Weiss law and magnetization measurements on MnNP, FeNP and CoNP below T=5 K can indicate ferrimagnetic ordering at low temperatures. A hysteresis behaviour in ZFC and FC magnetisation with the temperature of bifurcation T{sub b}=6 K was found for CoNP and FeNP. Moessbauer spectra taken at room temperature (besides FeNP) consist of a single symmetric quadrupole-split doublet with parameters {delta} and {delta} typical for Fe{sup II} ions in octahedral sites. A more complicated spectrum of FeNP is a consequence of different Fe environments.
This report presents criteria for the identification and evaluation of fire hazards in nuclear power stations. The report presents criteria that are consistent with the existing regulatory approach in Canada, and outlines engineering tools and analytical techniques currently available to deterministically analyse fire. The criteria presented cover the topics which should be included in a fire hazard analysis and provide details of each topic so that the accuracy of an analysis may be evaluated.
The externally fired combined cycle is emerging as an economically viable repowering options for old non-competitive coal fired steam plants. This paper describes the initial operation of a pilot plant located at Kennebunk, Maine and the initial work on the repowering of a 48MW coal fired steam plant located in Warren, PA.
A few metal complexes of isatin-isonicotinoylhydrazone with Ni(II), Cr(III), Co(II), Cu(II), Zn(II) and Cd(II) have been prepared and characterized on the basis of elemental analyses, infrared and electronic spectra as well as "1H NMR spectra, conductivity and magnetic measurements. In view of the results obtained, it has been found that two molecules of isatin-isonicotinoylhydrazone are chelated to the central metal ion as bis-uninegative ONO tridentate ligand forming non-electrolytic octahedral metal complexes. (author)
Water stress and fire disturbance can directly impact stand structure, biomass and composition by causing mortality and influencing competitive interactions among trees. However, open eucalypt forests of southwest Australia are highly resilient to fire and drought and may respond differently to increased fire frequency and aridity than forests dominated by non-eucalypt species. We measured the variation in stem density, basal area, stand biomass, sapwood area, leaf area and litterfall across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands along an aridity gradient in southwest Australia that had variable fire histories. Fire frequency was defined as the total number of fires over a ~30-year period and aridity as the ratio of potential evapotranspiration...
The difficulty in information communication and sharing are major problems for forest fire monitoring and early warning in China. As authors, we applied web service technology to a personal digital assistant (PDA) forest fire monitoring system and propose the framework of a monitoring system based on service-oriented architecture (SOA). At the same time, we describe the composition and function of web services from a server side and a client side. The method for developing a web service invocation engine on the PDA is introduced in detail. Finally, an example of a fire danger rating and fire weather services system are established, based on the Beijing Forest Fire Control System. The results show that the PDA forest fire monitoring system based on web services can effectively take advantag...
The nuclear power industry has experienced four carbon based adsorbent fires in its history, one was of the Monticello Standby Gas Treatment System and other three were in various off-gas delay beds. Although, some of the latter may not be classified as a full fledged fires. There were a number of experiments performed relating to igniting carbon beds and experiments relating to attempts at extinguishing set fires reported in the literature. Review of these experiments indicates that fire resulting from decay heat of adsorbed radioactive iodine is not justified even under the somewhat unrealistic source terms still in effect. At the same time the non-nuclear chemical industry application of carbon base adsorbents for solvent recovery has resulted in numerous fires and significant property losses. Fire control systems installed in nuclear air cleaning systems in ...
A 24-item short form of the 96-item Developmental Behaviour Checklist was developed to provide a brief measure of Total Behaviour Problem Score for research purposes. The short form Developmental...Full Text Available
This paper presents an overview of research conducted with the support of the Australian Institute of Nuclear Science and Engineering, at the University of Melbourne, School of Earth Sciences, Radiochemical Neutron Activation Laboratory. The primary objective of this research is to realize the high potential of the platinum group elements (PGE) and gold to the solution of petrogenetic problems, the study of magma generation and magmatic processes in mafic/ultramafic rock suites, as tracers in hydrothermal ore formation. The PGEs (Os, Ru, Ir, Pt, Pd and Rh) are among the least abundant of all elements on earth with unique properties such as high melting points, high electrical and thermal conductivity, high density, strength and toughness as alloys. They exhibit both siderophile and chalcophile characteristics and are valuable tools in providing information about magmatic processes, in particular S-saturation, as well as crystal fractionation trends. Two distinct groups of PGEs are ...
Fuel spray and air motion characteristics and combustion in direct injection (DI) diesel engines was studied using computational models of the commercial CFD-code FIRE. Physical subprocesses modelled included Lagrangian spray droplet movement and behaviour (atomisation, evaporation and interaction of spray droplets) and combustion of evaporated liquid spray in the gas phase. Fuel vapour combustion rate was described by the model of Magnussen and Hjertager. The standard k,{epsilon}-model was used for turbulence. In order to be able to predict combustion accurately, the fuel spray penetration should be predicted with reasonable accuracy. In this study, the standard drag coefficient had to be reduced in order to match the computed penetration to the measured one. In addition, the constants in the submodel describing droplet breakup also needed to be adjusted for closer agreement with the measurements. The characteristic time scale of fuel ...
Due to the high investment and operation costs incurred by dryers up to 50% of the proceeds from the cultivation of medicinal plants have to be spent on drying. This study was conducted in order to determine whether these costs can be lowered when solar energy is used. As little is known about the drying behaviour of medicinal plants even today one selected sage and camomile in order to study the influence of temperature, relative humidity, and drying air velocity on drying time and drug quality. Laboratory results were used as a basis for developing a solar hothouse dryer for medicinal plants which uses the whole roof surface as solar collectors with a batch dryer set up within the hothouse. In contrast to dryers of this type used up to now a foil green house with a gable roof was used. Installation of a central heating system helps to avoid bottlenecks, allows drying at night and increases plant flow by a factor of 3. The cost of heating oil, however, adds to the ...
Platinum(II) complexes have been investigated in the hydration of alkynes. These catalysts offer improved regioselectivity over Hg(II) counterparts. 1 fig., 2 tabs.
The Container Analysis Fire Environment (CAFE) computer code has been developed to model all relevant fire physics for predicting the thermal response of massive objects engulfed in large fires. It provides realistic fire thermal boundary conditions for use in design of radioactive material packages and in risk-based transportation studies. The CAFE code can be coupled to commercial finite-element codes such as MSC PATRAN/THERMAL and ANSYS. This coupled system of codes can be used to determine the internal thermal response of finite element models of packages to a range of fire environments. This document is a user manual describing how to use the three-dimensional version of CAFE, as well as a description of CAFE input and output parameters. Since this is a user manual, only a brief theoretical description of the equations and physical models is included.
Abstract To be self-sustaining in the longer-term and meet defined completion criteria, it is important that the management of restored bauxite mines can be integrated with the surrounding unmined Jarrah (Eucalyptus marginata) forest. A number of research projects relating to fire management have been undertaken in restored areas over the past 15 years. The broad objectives of these studies have been to assess the resilience of different-aged restored sites to fire and define the most suitable fire regime (season, intensity, and frequency) to utilize in the management of these areas. Restored areas were found to be a low fire risk up to five years of age because litter fuel was discontinuous and could not normally carry the fire. Between the ages of five and 12-15 years, restored areas wer...
This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference cell suggests the formation of a B-metal ...
The thesis describes work undertaken as part of a larger remote sensing based project which aims to detect, measure and monitor coal fires in two test areas in northern China. The first main topic addressed in this thesis is the detection of fires using several different thermal remote sensing data sets. The synergistic use of the different data sets is emphasised. The second major part of the thesis deals with thermal modelling of the coal fires. Three different models are developed, which allow a fire's depth, temperature, extent, total heat output and rate of movement to be determined. The models are tested both in the laboratory and using various field data sets. A model based on the assumption that the fire is a point heat source and that the temperature distribution around it is spherically symmetrical is shown to be the most effective. A simpler, one-dimensional coal ...
Wildland fire suppression personnel employed by the CDF do not currently have the equipment to protect themselves from the short-term acute affects of smoke from wildland fires. In addition, no regulations exist that specify appropriate respiratory protection and the current air-purifying respirator technology and carbon monoxide monitoring has not been adapted to fit wildland fire suppression requirements. This three-year limited study evaluated the ability of wildland fire fighters to perform their normal job function while wearing full-face air-purifying respirators. In the first two years of this study we designed, developed and field tested a prototype ``smart`` air-purifying respirator which incorporated a real-time carbon monoxide monitor into a commercial full-face respirator.` Data on carbon monoxide exposure while fighting wildland fires was collected. During the third ...
We describe a 59-year-old patient who developed acute renal failure because of rhabdomyolysis after extensive red fire ant bites. This case illustrates a serious systemic reaction that may occur from...Full Text Available
Dopaminergic (DA) neurons of the mammalian midbrain exhibit unusually low firing frequencies in vitro. Furthermore, injection of depolarizing current induces depolarization block before high...Full Text Available
The Nuclear Safety Commission acknowledged the policy of the Agency of Natural Resources and Energy to cope with these important matters on August 8, 1984. The main contents of the investigation and deliberation were as follows, As to the prevention of the occurrence of fires, the prevention of the leak and spread of inflammable liquid and gas, the installation of protective relays and so on, the use of incombustible materials and aseismatic design and the installation of lightning arresters. As to the detection of fires and fire fighting, the proper selection and arrangement of fire detectors and extinguishers, the extinguishers which do not harm the safety function of structures and equipment, and the extinguishers which are not affected by natural phenomena. As to the reduction of the effect of fires, the proper installation of fire walls and extinguishers, ...
The current trend towards the increased use of risk assessment in the regulation of nuclear power plants will inevitably result in changes in the analysis of fire protection systems and the methods of analysis. Before fire protection can be regulated on a risk basis, a consensus must be reached on a number of issues. One key issue is what types of computational tools will be allowable for analyzing fire events, and what types of scenarios those tools will be approved for use. Reaching this consensus will require an understanding of the types of computational tools available and their inherent advantages and disadvantages. To aid with this understanding, three different methods of fire simulation are applied to an oil pool fire test in the HDR (Heiss Dampf Reaktor) containment test facility. These methods are a hand calculation, the zone model code CFAST (Consolidated Model of ...
A controlled fire burner was constructed where various natural vegetation species could be used as fuel. The burner was equipped with thermocouples to measure fuel surface temperature and used as a...Full Text Available
Understanding feedbacks between terrestrial and atmospheric systems is vital for predicting the consequences of global change, particularly in the rapidly changing Arctic. Fire is a key process in this context, but the consequences of altered fire regimes in tundra ecosystems are rarely considered, largely because tundra fires occur infrequently on the modern landscape. We present paleoecological data that indicate frequent tundra fires in northcentral Alaska between 14,000 and 10,000 years ago. Charcoal and pollen from lake sediments reveal that ancient birchdominated shrub tundra burned as often as modern boreal forests in the region, every 144 years on average (+/- 90 s.d.; n = 44). Although paleoclimate interpretations and data from modern tundra fires suggest that increased burning was aided by low effective moisture, vegetation cover clearly played a critical role in ...
This progress report presents a detailed description of the background, technology and application, and Statement of Work for the development of a coal-fired pulse combustor for residential space heating.
Largest coal mine fires in the world are reported from Jharia coalfield in Dhanbad district, Bihar State of India. In this paper we report the utility of day and night time Thematic Mapper thermal IR data (120 m x 120 m) for detecting and monitoring mine fires in Jharia. For this purpose, seven sets of TM data acquired between 1985 to 1995 have been analysed. Data processing methods include geometric and radiometric corrections, conversion of DN values to at-satellite temperatures and colour coding of temperature images. The pixel-integrated temperatures of 50{degrees}C and above have been classified as mine fires and achieved an accuracy of 81.2%. Also, assessed year wise, colliery-wise and geological formation-wise mine fire distribution in this area. Although TM thermal data is of coarser resolution, it enabled detection of mine fires mainly because of the large areal extent and ...
This study analyzed the atmospheric emissions produced by the live firing of a 155 mm Howitzer gun. The study was conducted during a live firing training exercise at a Canadian Forces Base. Air emissions were sampled continuously for 3 hours. Particles and chemicals were accumulated on sampling media during the firing of 69 rounds. A single round was fired using 4 bags of propellants, and an additional 3 rounds were fired using 5 bags of propellant. Samples included particulate matter; hydrogen cyanide; polycyclic aromatic hydrocarbons (PAHs); dinitrotoluene compounds; benzene; toluene; ethylbenzene; xylene; metals; aldehydes; nitric acid; nitric oxide; nitrogen dioxide; hydrogen sulphide; and sulphur dioxide. Samples were collected at 8 m to the left of the gun as well as at 22 m in front of the gun muzzle in the line of fire. Results of the study showed that ...
T-type calcium channels are responsible for generating low-threshold spikes that facilitate burst firing and neurotransmitter release in neurons. GnRH neurons exhibit burst firing, but the underlying...Full Text Available
extravehicular activity; an exploding bridgewire firing unit for rocket engines ; a pressure transducer that can withstand the 6000 OF temperiiture ...
With the fire accident in Browns Ferry nuclear power plant as a turning point, the regulation against fire has been strengthened more strictly as seen in the regulatory guide of the United States Nuclear Regulatory Commission. Fire of cables is caused by either the ignition of a cable itself or spread of fire to cables. The aspect of fire is divided into the local ignition and combution and the fire extension and prepagation because of the line-shaped configuration of cables. This report describes the prevention of the spread of fire. As the materials for the prevention of fire spread, fire spread-preventing paint ''Dannekka'', sealant ''Danseal P and L'', and fire prevention tape ''FD tape'' are reported, and the testing method and the results are described in detail. ...
This article examines the developing market for independent power projects in Canada. The topics of the article include bidding in Ontario, the Quebec market, powering British Columbia, and market forces at work in Canada. Discussed are current projects in all stages of completion from bidding to production and includes gas-fired cogeneration, gas-fired combined-cycle electricity generation and cogeneration, wood-waste fired plants, repowering of existing utility plants, and hydroelectric power plants.
Aerosol and gas measurements were made with the University of Minnesota Mobile Laboratory (UMML) during the VISTTA programme near Page, Arizona. The UMML was stationed on Zilnez Mesa approx. 65 km east of the Navajo coal-fired power plant. Measurements were made both in and out of the power plant plume and were made during the day and night. Measured parameters included aerosol size distributions, Aitken nuclei count, ozone and sulphur dioxide concentrations, the aerosol light scattering coefficient, and meteorological parameters including ultraviolet radiation intensity. Concentrations of NO and NO/SUB/x were occasionally measured. Data show clear evidence of gas-to-particle conversion in the plume with aerosol volume being added in the 0.01 MUm - 0.32 MUm dia. range and new particles being formed. The observed excess aerosol volume depends strongly upon the SO/SUB/2 concentrations and the time of day with none observed in plume parcels which were not exposed to ...
Airborne fine particle sulfur data from the summer intensive of Project MOHAVE (Measurement of Haze and Visual Effects) was analyzed by the Receptor Model Applied to Patterns in Space (RMAPS) model, a novel multivariate receptor-oriented model that applies to secondary and primary species. The sulfur data from 17 sites were found to be well predicted by three spatial patterns interpreted as sources along the valley of the Colorado River (including the large Mohave coal-fired power plant, a smaller power plant and the city of Las Vegas); transport from sources located to the southwest; and transport from sources located to the southeast. The model was tested by using parameters derived from the 17-site data set to apportion sulfur for six sites that were not part of the original data set. The sulfur apportionment for these site sites was in agreement with the original apportionment and the physical interpretation of the spatial patterns given above. The effects of ...
We use a massively parallel 3D hybrid particle code, dHybrid, to simulate the deflection of plasma beams by a dipole like magnetic field in a laboratory environment. Dipole magnetic fields, along with a plasma injection source to inflate the magnetic field, are now being studied as means of deflecting solar wind and Energetic Particles away from spacecrafts [1,2,3]. We have considered three setups, consistent with the experiments, with a plasma beam fired at i) a dipole field with no plasma injection, ii) a plasma injection source with no dipole field and iii) a dipole field with a plasma injection source. The hybrid simulations help understand the relevant physical phenomena, and enable extrapolation to space plasma scenarios, where setups are similar but plasma parameters differ significantly. The simulation results consistently show the plasma beam being deflected by the dipole field, in the first scenario, with the deflecting distance ...
Full text of publication follows: The Nuclear Power Plants (NPPs) are always designed for the highest level of safety against postulated accidents which may be initiated due to internal or external causes. One of the external/internal causes, which may lead to accident in the reactor and its associated systems, is fire in certain vital areas of the plant. Conventionally, the fire containment approach and/or the fire confinement approach is used in designing the fire protection systems of NPPs. Indian NPPs (PHWRs) follow the combined approach to ensure plant safety and all newly designed plants are required to comply with the provisions of Atomic Energy Regulatory Board (AERB) fire safety Guide. In respect of older plants, the reassessment of adequacy of fire safety provisions in the light of current advances has becomes essential so as to decide upon the steps ...
The thermal environment of a hypothetical large indoor hydrocarbon pool fire is more complex compared to outdoor fires and can be more severe for engulfed objects. In order to analyze potential thermal environments for interim storage of spent fuel casks or low-level radioactive waste packages engulfed in pool fires numerical simulations with the CFD fire code FDS3 were carried out for different storage configurations. In addition, data of indoor pool fire experiments were used to validate the model for this type of application. A series of pool fire experiments under different ventilation conditions and varied pool surface (1 m"2 - 4 m"2) inside a compartment of 3.6 m x 3.6 m x 5.7 m was conducted at iBMB (Institut fuer Baustoffe, Massivbau und Brandschutz) of Braunschweig University of Technology, Germany. The instrumentation included thermocouples, heatflux ...
The U.S. Trade and Development Program (TDP) had received a request from the Hungarian Electricity Board (MVMT) for assistance in support of a feasibility study program to: (1) install new generation capability based on gas/oil fired combined cycle power plants, and (2) retrofit/refurbish a number of aging coal and oil fired steam plants. A Definitional Mission (DM) recommends that TDP fund the requested feasibility studies for new gas/oil fired combined cycle capabilities discussed in the Terms of Reference (TOR). Hungary will need to install significant new power capacity between now and the end of the century. Gas/oil fired combined cycle plants present probably the only option to install capacity rapidly. There is an opportunity for U.S. firms to supply technology and services with respect to these advanced power generation technologies.
...Synthesis of low-temperature, fast, single-firing body for porcelain stoneware tiles with coal gangue Synthesis of low-temperature, fast, single-firing body for porcelain stoneware ... tiles with coal gangue Synthesis of low-temperature, fast, single-firing body for porcelain stoneware tiles with coal gangue Wei et al.,... Article Synthesis of low-temperature, fast, single-firing body for porcelain stoneware tiles with coal gangue Qiangwei Wei1, Wenyuan Gao1*, and Xinguo ...According to phase diagram theory, a low-temperature, fast, single-firing body mix for porcelain stoneware tiles was designed in the quaternary system CaO-MgO-Al2O3-SiO2, using ...
Abstract Smoke is a mixture of toxic gases and suspended particulate matter of solids and liquids that evolves from a fire of flammable materials. This article presents real-time consequence modeling to track the concentration of individual species in smoke as well as its soot deposition. In the modeling process presented, the burning rate or vapor mass is fed into a combustion model in which the combustion of products has been identified and quantified along with the temperature of the fire. The output of the combustion model is the smoke that will be dispersed into the ambient. The fire geometry, which depends on the type of fire (e.g., pool or flare), is identified. A dispersion model with the capability of determining particulate deposition is then used for tracking the smoke plume. Th...
BACKGROUND AND CASE STUDY: Surgical fires are rare but preventable. During facial surgery for a 68-year-old man, a fire broke out, resulting in first- and second-degree burns after a nasal cannula ignited in an oxygen-rich environment because of improper draping and tenting. DISCUSSION: Operating room (OR) fires can be prevented if any component of the "fire triangle"-fuels, ignition sources, and oxidizers-is reduced or eliminated. The use of supplemental oxygen in the OR via nasal cannulae, nebulizers, and oxygen cylinders must always considered a potential source of fire. Deficits in knowledge among the surgical team with respect to the prevention and management of surgical fires were apparent. A plan was put into place to improve fire safety education, entailing an educational program that is included in intern and resident orientation. ...
New tetradentate N(2)O(2) donor Schiff bases and their mononuclear Co(II), Ni(II), Cu(II), and Pd(II) complexes were synthesized and characterized extensively by IR, (1)H-, (13)C-NMR, mass, ESR, conductivity measurements, elemental and thermal analysis. Specifically the magnetic and electronic spectral measurements demonstrate the octahedral structures of cobalt(II), nickel(II) complexes and square planar geometries of copper(II), palladium(II) complexes. All the ligands and complexes were screened for their in vitro antibacterial activity against two gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli, Klebsiella pneumonia). In this study, Pd(II) complexes exhibited potent antibacterial activity against B. subtilis, S. aureus whereas ...
Future insertion quadrupoles with large apertures and high gradients will be required for the Phase II luminosity upgrade (10{sup 35} cm{sup -2}s{sup -1}) of the Large Hadron Collider (LHC). Although improved designs, based on NbTi, are being considered as an intermediate step for the Phase I upgrade, the Nb{sub 3}Sn conductor is presently the best option that meets the ultimate performance goals for both operating field and temperature margin. As part of the development of Nb{sub 3}Sn magnet technology, the LHC Accelerator Research Program (LARP) developed and tested several 1-meter long, 90-mm aperture Nb{sub 3}Sn quadrupoles. The first two series of magnet used OST MJR 54/61 (TQ01 series) and OST RRP 54/61 (TQ02 series) strands. The third series (TQ03) used OST RRP 108/127 conductor. The larger number of sub-elements and the consequent reduction of the effective filament size, together with an increased fraction of copper and a lower Jc were expected to improve ...
Time-temperature-precipitation diagrams have been established for two steels with 6% Mo, 21% Cr, 25% Ni, 0.14 and 0.19% N (Cronifer 1925 h Mo = 1.4529, UNS N 08925) and for one steel with 6% Mo, 20% Cr, 18% Ni and 0.21% N (UNS S 31 254). The corresponding time-temperature-sensitization diagrams (in accordance to SEP 1877/II) and time-temperature-pitting diagrams (testing in 6% FeCl{sub 3} solution) have been evaluated as well. Precipitation of intermetallics occurs rapidly especially in the range between 700 and 1000{sup 0}C. In case of the 18% Ni steel and the 25% Ni/0.14% N steel grain boundaries are covered to a large extent with precipitates after only 15 min at 850 or 950{sup 0}C. In case of the 25% Ni/0.19% N steel precipitation is considerably slower. Therefore, when welding according to established rules and recommendations, no deterioration of the corrosion resistance in the heat-affected zone is to be expected. Additionally, the steel with 25% Ni has an ...
The effect of phosphorus on the corrosion resistance of Al-bronzes is studied in detail in this work. A literature review showed that there are a lot of things known about the microstructure and the mechanical properties of Al-bronzes. In spite of their corrosion resistance the corrosion properties and the structure of the protective oxide films of Al-bronzes were seldom a matter of interest. Systematic studies of the influence of different alloying elements on the oxide film and the corrosion properties are rare. Therefore, it is not possible to predict the corrosion resistance of Al-bronzes, made by alloying particular elements. The high corrosion resistance of the new alloy CuAl_2_0P_1 was the reason to investigate the influence of phosphorus on the corrosion properties of Al-bronzes in more detail. A systematic study of the microstructure and the corrosion properties of Cu, CuP_x, CuAl_2_0 and CuAl_2_0P_x offers an insight into the effect of aluminium and phosphorus on the ...
Six major use pesticides (Atrazine, Dicamba, Isoproturon, Lindane, Paraquat and Trifluralin) with differing physico-chemical properties were evaluated for the significance of 'bound' or non extractable residue formation. Investigations were carried out in purpose-built microcosms where mineralization, volatilisation, 'soil water' extractable and organic solvent extractable residues could be quantified. Extractable residues were defined as those accessible by sequential extraction where the solvent used became increasingly non-polar. Dichloromethane was the 'harshest' solvent used at the end of the sequential extraction procedure. {sup 14}C-labelled volatilised and {sup 14}CO{sub 2} fractions were trapped on exit from the microcosm. The pesticides were categorised into 3 classes based on their behaviour. (i) Type A (Atrazine, Lindane and Trifluralin) in which ring degradation was limited as was the formation of ...
We have tested the suitability of a new single-aliquot regenerative-dose protocol for estimating the equivalent dose (D_e) in polymineral fine grains extracted from colluvia from various sites in Germany. First, we report the behaviour of three OSL signals: (i) blue-stimulated, (ii) infrared-stimulated luminescence, and (iii) blue-stimulated luminescence following infrared (IR) stimulation, using a near-UV (290-380 nm) detection window in each case. For these three signals, there is a significant change in sensitivity with regeneration cycle; this change can be compensated for using the response to a fixed test dose after each natural or regenerated measurement. The source of the three luminescence signals is then investigated using pulse-anneal and elevated-temperature experiments. Fading tests on laboratory-induced signals show that although the IR signals fade by up to 23% in 15 days at 100 deg. C, the post-IR blue signals are stable. The ...
Proposals for use of Alloy 800 as a H.T.R. boiler material have prompted studies of its creep and high temperature fatigue properties in impure helium with comparative tests in air. In impure helium, as expected in a H.T.R., reactions of potential importance are selective oxidation (of chromium, aluminium and titanium) and possibly carburisation from carbon monoxide or methane. In air, general oxidation will occur, possibly accompanied by nitridation. The effects of these reactions will depend on specimen geometry and the nature of the deformation. Two important possibilities are: (i) that environment affects the structure and properties of a surface zone of material undegoing uniform deformation (this may modify creep rate and crack nucleation); and (ii) that environment affects behaviour of a small region (e.g. at the root of a notch or ahead of a crack) in a specimen undergoing non-uniform deformation (this will modify crack growth and hence ...
Some acylhydrazine derived ONO donor Schiff bases and their Co(II) and Ni(II) complexes have been prepared having the same metal ion (cation) but different anions. These synthesized metal(II)...Full Text Available
On July 18, 2001, a freight train carrying hazardous (non-nuclear) materials derailed and caught fire while passing through the Howard Street railroad tunnel in downtown Baltimore, Maryland. The United States Nuclear Regulatory Commission (USNRC), one of the agencies responsible for ensuring the safe transportation of radioactive materials in the United States, undertook an investigation of the train derailment and fire to determine the possible regulatory implications of this particular event for the transportation of spent nuclear fuel by railroad. Shortly after the accident occurred, the USNRC met with the National Transportation Safety Board (NTSB), the U.S. agency responsible for determining the cause of transportation accidents, to discuss the details of the accident and the ensuing fire. Following these discussions, the USNRC assembled a team of experts from the National Institute of Standards and Technology (NIST), ...
BackgroundTo determine male outpatient attenders' sexual behaviours, expectations and experience of talking about their sexuality and sexual health needs with a doctor.MethodsA...Full Text Available
ObjectivesTo investigate the effect of group cognitive behavioural therapy (CBT) for fatigue self-management, compared with groups receiving fatigue information alone, on fatigue...Full Text Available
Given the high prevalence of overweight and low levels of physical activity among children, a better understanding of physical activity behaviour is an important step in intervention planning. This...Full Text Available
Here, we show that the consequences of deficient micronutrient (β-carotene) intake during larval stages of Manduca sexta are carried across metamorphosis, affecting adult behaviour....Full Text Available
Comparative sociogenomics has the potential to provide important insights into how social behaviour evolved. We examined brain gene expression profiles of the primitively eusocial wasp Polistes...Full Text Available
Behavioural assessment methods have been used to signal the need for intervention and to evaluate treatment effectiveness. Direct observation and rating scales have been used to assess pain and distress...Full Text Available
A structurally conserved element, the trigger loop, has been suggested to play a key role in substrate selection and catalysis of RNA polymerase II (pol II) transcription elongation. Recently resolved...Full Text Available
The insulin/IGF-1 signaling (IIS) pathway is a conserved regulator of longevity, development, and metabolism. In Caenorhabditis elegans IIS involves activation of DAF-2 (insulin/IGF-1...Full Text Available
DNA from the peripheral blood mononuclear cells of 17 different individuals infected with human T-cell lymphoma/leukemia virus type II (HTLV-II) was successfully amplified by the polymerase chain reaction...Full Text Available
We show that the chaotic dynamical behaviour displayed by diagonal Bianchi type IX metrics in general relativity does not occur on approach to the singularity in higher-order lagrangian theories of gravity. However, chaotic behaviour does occur in the more general non-diagonal type IX models in these theories. An interpretation of these results in terms of the hamiltonian potential picture of the type IX evolution is given. (orig.).
We show that the chaotic dynamical behaviour displayed by diagonal Bianchi type IX metrics in general relativity does not occur on approach to the singularity in higher-order lagrangian theories of gravity. However, chaotic behaviour does occur in the more general non-diagonal type IX models in these theories. An interpretation of these results in terms of the hamiltonian potential picture of the type IX evolution is given. (orig.).
The Nuclear Regulatory Commission (NRC), working with the National Institute of Standards and Technology (NIST), Pacific Northwest National Laboratory (PNNL), and the National Transportation Safety Board (NTSB), performed analyses to predict the response of various spent fuel transportation cask designs when exposed to a fire similar to that which occurred in the Howard Street railroad tunnel in downtown Baltimore, Maryland on July 18, 2001. The thermal performance of three different spent fuel cask designs (HOLTEC HI-STAR 100, TransNuclear TN-68, and NAC-LWT) was evaluated with the ANSYSR and COBRA-SFS analysis codes, utilizing boundary conditions for the tunnel fire obtained using NIST's Fire Dynamics Simulator (FDS) code. NRC Staff evaluated the potential for a release of radioactive material from each of the three transportation casks analyzed for the Baltimore tunnel fire scenario. The results of ...
The present article describes the features of the fully-fired combined cycles and the outline of the plant. Hitachi has optimized fully-fired combined cycle systems by executing a heat recovery type combined cycle. For the fully-fired combined cycles, it is possible to raise plant efficiency through the selection of adequate gas turbine types and cycles. It is possible to apply existing boiler facilities, fuel combustion systems, and stacks. It is possible to execute civil and architectural works on existing plants in-service as well as modification works during routine inspections. The NOx increment by gas turbine unit installations can be reduced by denitration plant modifications. Examples of the fully-fired combined cycles under planning are also introduced. Furthermore, the relational technique and operational characteristics are mentioned, as for combustion characteristics under low oxygen ...
The primary objective of the project is to investigate the long-term effects of commercially available tangentially-fired low NO{sub x} combustion technologies on NOx emissions and boiler performance on Unit 2 at Gulf Power Company`s Plant Lansing Smith located near Lynn Haven, Florida. The project will characterize emissions and performance of a tangentially-fired boiler operating in the following configurations: Baseline ``as-found`` configuration: Phase 1; retrofitted low NO{sub x} concentric firing system (LNCFS) Level 2 and simulated low NO{sub x} bulk furnace staging (LNBFS): Phase 2; retrofitted low NO{sub x} concentric firing system (LNCFS) Level 3, Phase 3a and simulated LNCFS Level 1, Phase 3b.
The primary objective of the project is to investigate the long-term effects of commercially available tangentially-fired low NO{sub x} combustion technologies on NOx emissions and boiler performance on Unit 2 at Gulf Power Company's Plant Lansing Smith located near Lynn Haven, Florida. The project will characterize emissions and performance of a tangentially-fired boiler operating in the following configurations: Baseline as-found'' configuration: Phase 1; retrofitted low NO{sub x} concentric firing system (LNCFS) Level 2 and simulated low NO{sub x} bulk furnace staging (LNBFS): Phase 2; retrofitted low NO{sub x} concentric firing system (LNCFS) Level 3, Phase 3a and simulated LNCFS Level 1, Phase 3b.
ObjectivesThe overall aim of this proposal is to make use of the unique opportunity afforded by the 2010 Amazonian Drought in order to quantify the basin-wide impacts of an intense forest fire season on above and below-ground carbon stocks and ecophysiological changes in forest functioning. The specific objectives relating to our research questions are: O1. Assess the causes and spatial extent of the 2010 drought in terms of basin-wide rainfall anomalies and water deficits and their relationship wi [continued...]DescriptionDespite an 82% decline in deforestation rates in Amazonia, fires are still on the rise. 2010 has been a year of severe drought and fire in Amazonia. Over the last months (July and August) the number of fire counts has reached 80% of the 2005 values, which was characterized as the drought of the century. Through the beginning of September, fire outbreaks have ...
The application of foam in dealing with underground fire is well known due to its smothering action by cutting off air feed to burning fuel as well as acting as coolant. Besides plugging air feed to fire, water could be virtually reached to the fire affected areas much beyond the jet range as underground galleries with low roof restrict jet range of water. This method also enables a closer approach of a fire fighting team by isolating the toxic gases and smoke with a foam plug. The paper describes the development of high expansion foam composition and its application technology in order that foam plug method can be suitably utilized for combating mine fires in India. Three compositions were recommended for generation of high expansion foam: (a) 0.5% sodium/ammonium lauryl sulphate, 0.15 to 0.2% sodium carboxy methyl cellulose, 0.1% booster; (b) 0.5% sodium/ammonium lauryl sulfate, ...
Tightening environmental regulations and the signing of the Kyoto protocol have prompted electric utilities to consider co-firing biomass with coal to reduce the levels of CO{sub 2}, SO{sub 2} and NOx in stack emissions. This analysis examines the cost competitiveness of plantation produced woody biomass and waste wood with coal in electricity production. A case study of woody biomass production and co-firing in northern Indiana is presented. A linear programming model was developed to examine the optimal co-firing blend of coal and biomass while minimizing variable, cost, including the cost of ash disposal and material procurement costs. This model was used to examine situations where coal is the primary fuel and waste wood, willow trees, or both are available for fuel blending. The results indicate that co-firing woody biomass is cost-effective for the power plant. Sensitivity analysis explored the ...
The results of this research centered on the experimental studies of a single superconducting persistent current qubit, the implementation of type-II algorithms using these qubits, and the proposal for adiabatic quantum computing using these qubits. The m...
The in vivo photochemical activity of photosystem II was inferred from modulated chlorophyll fluorescence and photoacoustic measurements in intact leaves of several plant species (Lycopersicon...Full Text Available
Woolfolk, C. A. (University of Washington, Seattle). Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. II. Stoichiometry with inorganic...Full Text Available
... and high-quality photospheric-phase Type II SN spectra to constrain core- collapse SN explosions, massive star evolution, and distances in the Universe ...
This document describes payload control at LLNL to ensure that all shipments of CH-TRU waste in the TRUPACT-II (Transuranic Package Transporter-II) meet the requirements of the TRUPACT-II SARP (safety report for packaging). This document also provides specific instructions for the selection of authorized payloads once individual payload containers are qualified for transport. The physical assembly of the qualified payload and operating procedures for the use of the TRUPACT-II, including loading and unloading operations, are described in HWM Procedure No. 204, based on the information in the TRUPACT-II SARP. The LLNL TRAMPAC, along with the TRUPACT-II operating procedures contained in HWM Procedure No. 204, meet the documentation needs for the use of the TRUPACT-II at LLNL. Table 14-1 provides a summary of the LLNL waste generation and ...
Biosorption using activated sludge biomass (ASB) as a potentially sustainable technology for the treatment of wastewater containing different metal ions (Cd(II), Pb(II) and Zn(II)) was investigated. ASB metal uptake clearly competed with protons consumed by microbial biomass compared with control tests with non-activated sludge biomass. Biosorption tests confirmed maximum exchange between metal ions and protons at pH 2.0-4.5. It was revealed by the study that the amount of metal ions released from the biomass increased with biomass sludge concentration. The result showed that maximum absorption of metal ions was observed for Cd(II) at pH 3.5, Pb(II) at pH 4.0, and pH 4.5 for Zn(II) ions. The maximum absorption capacities of ASB for Cd(II), Pb(II) and Zn(II) were determined to be 59.3, 68.5 and 86.5%, ...
On July 18, 2001, a freight train carrying hazardous (non-nuclear) materials derailed and caught fire while passing through the Howard Street railroad tunnel in downtown Baltimore, Maryland. The United States Nuclear Regulatory Commission (USNRC), one of the agencies responsible for ensuring the safe transportation of radioactive materials in the United States, undertook an investigation of the train derailment and fire to determine the possible regulatory implications of this particular event for the transportation of spent nuclear fuel by railroad. Shortly after the accident occurred, the USNRC met with the National Transportation Safety Board (NTSB, the U.S. agency responsible for determining the cause of transportation accidents), to discuss the details of the accident and the ensuing fire. Following these discussions, the USNRC assembled a team of experts from the National Institute of Standards and Technology (NIST), ...
The purpose of this study was to determine if nitrogen loss from prescribed fire can be mitigated by reducing the amount of large fuel on a clearcut prior to burning. We examine the relations between nitrogen loss and duff consumption by prescribed fire with respect to the amount of woody biomass on the unit and the moisture content of that biomass before burn. Equations are presented to predict duff consumption from preburn conditions. Sources of variability of nitrogen concentration and content of duff within and between units are also evaluated.
The fire protection practices adopted at nuclear power stations generally follow the well established principles used throughout industry. Unfortunately, there is one particular area - the interaction with heating, ventilation and air conditioning (HVAC) services - where nuclear power stations pose a seemingly insoluble conflict: that between the need to contain and the need to ventilate. Now, however, solid state fire dampers using power fluidics may promise a solution. One of the key characteristics of a fluidic device is that it is 'solid state', i.e. it has no moving parts. Because of this, its inherent reliability is orders of magnitude greater than a mechanical device. (U.K.).
This article describes how a natural gas-fired combined cycle with increased firing temperature, reduced cooling air usage, improved component efficiencies, and cycle enhancements could achieve a lower heating value plant efficiency of greater than 60%. Today's gas turbine systems feature high fuel-to-electricity efficiencies. Efficiencies, on a lower-heating-value (LHV) basis, for large natural gas-fired combined-cycle systems for the utility market have been demonstrated at 54%. Even though manufacturers will make improvements in the 1990s, efficiency levels will reach a plateau. Cycle innovations and gas turbine design changes will achieve LHV efficiencies in the 60% range for natural gas-fired utility machines.
The removal of toxic metals and alkalis from gas streams at high temperatures was investigated. This is important for the development of coal-fired combined cycle power generation systems.
... The other standards in this group deal with heat exchangers, insulation, marking, valves, hydraulic cleanliness, storage of LPG, and centrifugal fire ...
... Division and the 82nd ABN Division spearheaded a ... attack through the stalled 90th Division to ... mi,_es, which included airborne infantrv, regular ...
This paper attempts to clarify the most common measures available for the fire and electrical engineer in the prevention of polychlorinated biphenyl (PCB) hazards. It points out the risks and the potential...Full Text Available
The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...
... being pulled out of water, the movement is restricted ... This heating depended on the particle size ... hydrometeor injection into the upper tropopause. ...
and the Wildland Firefighter Foundation. To request a marker click here. Engraved bricks may also be purchased from the Foundation to become part of the site. To request a...
Moessbauer spectra of the imitative ancient Jun porcelain indicate that the glaze and body materials contain Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4} and structural iron. It is clear that during the firing process, the glaze undergoes dehydration, dehydroxylation, vitrification and recrystallization. The Fe{sup 2+} quadrupole splitting value of the paramagnetic peak of the body material is high even at low firing temperatures. For the body material, the distinction between dehydration and dehydroxylation is not clear. The changes of magnetism of the glaze and body materials in the firing process and the coloring mechanism of the sky-blue Jun porcelain are analyzed in the present paper. (orig.)
this, however, was a real environmental threat since various drums containing jet fuel, Bunker C, diesel and other petroleum derivatives were on fire. The CAPECO...
Proton-conducting solid oxide fuel cells, incorporating BaZr0.1Ce0.7Y0.2O3-? (BZCY) electrolyte, NiO-BZCY anode, and Sm0.5Sr0.5CoO3-?-Ce0.8Sm0.2O2-? (SSC-SDC) cathode, were successfully fabricated by a combined co-pressing and printing technique after a one-step co-firing process at 1100, 1150, or 1200 oC. Scanning electron microscope (SEM) results revealed that the co-firing temperature significantly affected not only the density of the electrolyte membrane but the grain size and porosity of the electrodes. Influences of the co-firing temperature on the electrochemical performances of the single cells were also studied in detail. Using wet hydrogen (2% H2O) as the fuel and static air as the oxidant, the cell co-fired at 1150 oC showed the highest maximum power density (PDmax) of 552 and 370 mW cm-2 at 700 and 650 oC, respectively, while the one co-fired at 1100 oC showed the ...
... The subjects in this field experiment were volunteer infantrymen from the 82nd Airborne Division and the 101st Airborne Division (Air Assault). ...
Statement of problem Titanium is the most biocompatible metal used for dental casting; however, there is concern about its marginal accuracy after porcelain application since this aspect has direct influence on marginal fit. Purpose The purpose of this study was to determine the effect that metal selection and the porcelain firing procedure have on the marginal accuracy of metal ceramic prostheses. Material and methods Cast CP Ti, milled CP Ti, cast Ti-6Al-7Nb, and cast Ni-Cr copings (n=5) were fired with compatible porcelains (Triceram for titanium-based metals and VITA VMK 95 for Ni-Cr alloy). The Ni-Cr alloy fired with its porcelain served as the control. Photographs of metal copings placed on a master die were made. Marginal discrepancy was determined on the photographs using an image ...
An essential part of fire risk assessment is the analysis of fire hazards and fire propagation. In this work, models and tools for two different aspects of numerical fire simulation have been developed. The primary objectives have been firstly to investigate the possibility of exploiting state-of-the-art fire models within probabilistic fire risk assessments and secondly to develop a computationally efficient solver of thermal radiation for the Fire Dynamics Simulator (FDS) code. In the first part of the work, an engineering tool for probabilistic fire risk assessment has been developed. The tool can be used to perform Monte Carlo simulations of fires and is called the Probabilistic Fire Simulator (PFS). In Monte Carlo simulation, the simulations are repeated multiple times, ...
This BCRS project demonstrates the use of SAR interferometry for measuring and monitoring land subsidence caused by underground coal fires and underground mining in a remote area of north west China. China is the largest producer and consumer of coal in the world. Throughout the N.W., N. and N.E. of China, the coal-seams are very susceptible to spontaneous combustion, causing underground coal fires. As the thick coal seams are burned out, the overburden collapses, causing land subsidence, and producing new cracks and fissures, which allow more air to penetrate and continue the fire to spread. SAR interferometry, especially differential interferometry has been shown to be able to measure small differences in surface height caused by such land subsidence. This report describes the problems, the test area, the procedures and techniques used and the results obtained. It concludes with a description of some of the problems ...
Chewing up the Forest: Bark-Eating Beetles Provide Timber for Forest Fires. Droughts in California allow bark beetles to lay eggs into sapless trees, ...
Fuel treatments are being implemented on public and private lands across the western United States. Although scientists and managers have an understanding ... ...
The thermomechanical behaviour of clayey soils was examined in a laboratory study because of their importance in some engineering applications such as hydrocarbon extraction from oil-bearing sands and radioactive waste disposal. The slightest temperature variations have been known to have an impact on the mechanical behaviour of clayey soils. In this study, tests were conducted on reconstituted and natural clayey soils using triaxial cells modified to control temperatures. Changes of temperature and stress state were not applied simultaneously. Instead, the tests were divided into two separate sections aimed at studying the thermal and mechanical behaviour of clays. The thermal behaviour tests examined the deformations induced by drainage temperature changes as well as pore-pressure generation and consolidation phenomena. The mechanical behaviour tests, focused on the influence of ...
The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.
PRESTO-II is a computer code developed to evaluate possible health effects from shallow land disposal of low level radioactive wastes. PRESTO-PREP is a data preprocessor that has been developed to expedite the formation of input data sets for PRESTO-II. PRESTO-PREP utilizes a library of nuclide and risk-specific data. Given an initial waste inventory, the code creates the radionuclide portion of the associated input data set for PRESTO-II. 2 references.
The purpose of this paper is to describe the embedded computer systems approach taken at Experimental Breeder Reactor II (EBR-II) for non-safety related systems. The hardware and software structures for typical embedded systems are presented The embedded systems development process is described. Three examples are given which illustrate typical embedded computer applications in EBR-II.
Angiotensin II (Ang II) is a key proapoptotic factor in fibrotic tissue diseases. However, the mechanism of Ang-II-induced cell death in endothelial cells has not been previously elucidated....Full Text Available
The most developed systems for the generation of electricity from coal are the Integrated coal Gasification Combined Cycle (IGCC) and the Pressurized Fluidized Bed Combustion (PFBC) system. They both represent state-of-the-art technology and provide electric power at 41-46% LHV efficiency. However, the high level of complexity leads to lower reliability and higher costs. A simpler system, based on a coal-fired steam boiler integrated with a gas turbine, has been proposed. In such a plant, known as the externally fired combined cycle (EFCC), compressed air is heated indirectly in a heat exchanger located in the coal furnace. The hot air is then expanded in a turbine, and the exhaust is passed on to the coal furnace as preheated combustion air. Steam produced in the boiler generates additional power in a steam turbine. The exclusion of coal combustion products from the gas turbine avoids hot gas clean-up and turbine blade corrosion by coal ash. ...
The paper discusses the potential environmental impacts associated with the operation of a large, say 350 MWe, gas-fired combined cycle power station. It concludes that if appropriate control methods are introduced at the design stage of the plant, environmental impacts are minimal and can be considered acceptable. (author).
Lectures were held on forest and wood management, the forest as an energy source and the emission problem of wood combustion, future emission limitating regulations for wood firing, influence of firing technique on air pollution abatement and constructive and operational air pollution abatement measures with manually and continuously fuelled furnaces.
The present invention provides an improvement in the art of combined steam turbine and gas turbine power plants of the type wherein the principal source of energy is a fluidized bed combustor fueled by coal. More specifically, the invention pertains to supplemental firing of the gas turbine cycle with a clean hydrocarbon fuel (CHF) at a high incremental efficiency to significantly increase overall plant efficiency.
Amidst the explosion of greenfield natural gas-fired combined-cycle plant development, opportunities still exist for valuable plant repowering and retrofits by taking advantages of unique technical and market conditions. One of the projects discussed is the rebuilding of the coal-fired Hawthorne unit 5 damaged by a boiler explosion. 3 tabs., 5 photos.
The systems analyses and optimization studies performed in connection with a program to design and evaluate a commercial 663 MWe coal-fired combined cycle power plant using pressurized fluidized bed combustion and advanced technology in the hot gas cleanup system and gas turbines are presented. Details on the plant control system are included. (LCL)
A final report is presented on the design, environmental characteristics, performance and maintainability, and economic analysis of a commercial 663 MWe coal-fired combined cycle power plant using pressurized fluidized bed combustion, and advanced technology in the hot gas cleanup system and gas turbines. Experimental data on the performance of each of the major components are included. (LCL)
The paper describes the Integrated Air Pollution Control System (IAPCS), a computerized program that can be used to estimate the cost and performance of pre-combustion, in situ, and post-combustion air pollution control configurations in pulverized-coal-fired utility boilers of 1...
Korea Electric Power Corporation (Kepco) of South Korea has awarded Asea Brown Boveri Switzerland, a member of the ABB Group, a contract to supply the main equipment for two gas-fired combined-cycle power stations. News of the contract followed an announcement last year that Kepco will build a series of gas-fired power stations in the early 1990s to supply electricity to new housing and commercial areas being built in the Seoul-Incheon connurbation. (author).
The object of this study was to identify those areas in California where synthetic fuel-fired power plants could be sited in the 1990 time frame, from an air quality perspective. The synfuel-fired power plants considered in this new study were 500 Mw methanol-fired combined cycle (MFCC) and 500 Mw integrated gasifier combined-cycle (IGCC) units. For comparison purposes, 500 Mw direct coal-fired boilers and 500 Mw natural gas-fired combined-cycle units were also considered. Staff did not attempt to locate plants at any specific sites, but relied primarily upon a regional countywide analysis. The study provides an approximation, for planning purposes, of a reasonable limit of the state's power plant siting capacity, given the plant types and sizes, conditions, and assumptions specified. The study shows that local emission limitations often preclude certain types of power ...
An extended series of measurements at a conventional coal-fired boiler equipped with a wet-limestone flue gas desulfurization unit has shown that sulfate and sulfur dioxide removal efficiencies are dissimilar. The average SO2 scrubbing efficiency was 76% and was observed to decrease over a five-day operating cycle. Total sulfate scrubbing efficiency, averaging about 29%, was invariant throughout the operating cycle. (1 diagram, 3 tables)
Carbalkoxylation of vinyl electrophiles was investigated using platinum complexes. This reaction occurs in two steps: (a) carbonyl insertion of {sigma}-vinyl Pt(II) halides and (b) alcoholysis of vinylic acyl Pt(II) complexes. Alcoholysis of vinylic acyl Pt(II) triflate complexes is investigated kinetically. Vinylic acyl Pt(II) complexes were isolated and characterized. 51 refs., 5 figs., 6 tabs.
In March 1980, administrators of Clarkson College of Technology made a decision to convert the college's downtown heating plant to one that can rely on wood as a fuel. The decision was prompted by high costs of oil and gas needed to heat the downtown campus. In October 1981, a wood-fired plant with a rated steam production capacity of 10,500 lb/hour went into a trial operation. The plant cost $685,742 which includes $625,642 for material and labour and $60,100 for engineering. In the 1981 to 1982 heating season, it supplied 55 percent of the steam needs of the downtown campus with a wood fuel consumption of 2,857 tons. Under normal operation, the wood-fired plant will require about 4,500 tons of green wood chips per heating season. The investment in the wood-fired plant is expected to have a real rate of return (after discounting inflation) in the range of 20 to 23 percent per year. This study, sponsored by the New ...
Red mud, which is a pollutant residue from the extraction of alumina from bauxite ore, was utilized as an additive to a well blended mixture of three Egyptian clays, feldspar, quartz and grog. This was added in gradual proportions to study its effect on the vitrification properties of fired samples. Samples were moulded under a pressure of 20.7 MPa and fired at temperatures ranging from 950 C to 1100 C for soaking periods up to three hours. Compressive strength was determined as function of percent red mud added and firing temperature. A semi-exponential relation was established between strength and apparent porosity. 50 x 50 mm tiles containing 70% red mud addition and fired at 1100 C for one hour were tested. They were found to match the standards required for glazed wall tiles bodies. Tiles fired at 1100 C for 3 hours were compatible with the standards for glazed floor tiles. ...
Metastable austenitic steels show excellent mechanical properties, such as high strength combined with excellent ductility and toughness due to martensitic transformation under mechanical loading (transformation induced plasticity effect). A good energy consumption, and, in the case of high-alloyed metastable austenitic steels, a high corrosion resistance, increase the potential of these materials for diverse applications, also in regard of safety requirements. Up to now, numerous wrought alloys were investigated concerning mechanical behaviour, TRIP-effect, martensitic transformation behaviour and modelling of transformation kinetics or stress-strain behaviour. New high alloyed cast CrMnNi-steels, developed at Technical University Bergakademie Freiberg, provide the chance to reduce processing steps, production time and costs. In order to understand the influence of temperature on the martensitic phase transformation ...
Solar heating of gas turbine plants steps back more and more into the focus of current research. The mainly instationary operation of solar turbine power plants can only be predicted with sufficient accuracy if the transient behaviour of the receiver for the solar radiation is known. Therefore the transient behaviour of cavity receivers of different design is investigated. The mathematical model used for the simulation of the heat transfer and energy storage processes is illustrated. Computed results for receivers with various inner lining are compared and evaluated concerning their use in practice.
The present paper considers the evaluation of timber structures with the focus on robustness due to connection ductility. The robustness analysis is based on the structural reliability framework applied to a simplified mechanical system. The structural timber system is depicted as a parallel system. An evaluation method of the ductile behaviour is introduced. For different ductile behaviours, the system reliability is estimated based on Monte Carlo simulation. A correlation between the strength of the structural elements is introduced. The results indicate that the reliability of a structural timber system can be significantly increased due to the ductile behavior.
The second international conference on containment design and operation included sessions on the following topics: performance and regulatory requirements; radionuclide behaviour; severe accident design and analysis; operation, maintenance, leaking and aging of containment systems; thermal hydraulic behaviour of containment systems; hydrogen mixing and mitigation; design methods and concepts; code validation; structural analysis and response tests; passive safety systems; aerosol behaviour; containment reliability, integrity, and risk assessment; hydrogen deflagration and detonation. Due prominence was given to CANDU and other PHWR reactors. The individual papers have been abstracted separately.
This study examines the effects of blasting on waste dumps at open pit mining operations. Of specific concern were mining operations at the base of a five hundred foot high waste dump such as the operation at the South Pit of the Smoky-River Coal Ltd. property near Grande Cache, Alberta. An assessment of waste dump stability including factors such as quasi-static deformation behaviour, historical dump deformation behaviours and potential blasting effects was undertaken. It is concluded that safe blasting may be carried out in proximity to waste dumps, but monitoring of dump behaviour is recommended to ensure operational safety. 22 refs., 4 apps.
Marketing-led enterprise change management initiated by a major UK contractor is explored in this paper as a contrast to procurement-led changes to projects driven by clients. Procurement-led initiatives try to induce changes to behaviour through market governance. Relationship marketing and management proactively change organizational behaviour, the enterprise taking responsibility for its own destiny. Investment and resource allocation, and organizational behaviour have posed constraints, particularly concerning service continuity in construction. Overcoming these constraints offers opportunities for delivering service improvements and adding value for clients and yielding further increases in repeat business and increasing profitability. Relationship marketing is the conceptual starting...
The subfornical organ is a major receptor area for one of the principal stimuli of thirst, the octapeptide, angiotensin II. In conscious water-sated rats, the authors examined the effects of intravenous infusion of angiotensin II on the rate of glucose utilization in the subfornical organ and in structures anatomically and functionally connected with it. Angiotensin II produced pressor and drinking responses and increased glucose utilization selectively in the subfornical organ and pituitary neural lobe and in no other brain structure. Treatment with the angiotensin II antagonist, sar1-leu8-angiotensin II, before intravenous administration of angiotensin II prevented metabolic stimulation of the subfornical organ and neural lobe. Captopril, an inhibitor of angiotensin-converting enzyme, reduced subfornical organ glucose metabolism to a level similar to that ...
Adsorptive removal of Pb(II) ions from aqueous solution onto a non-activated charcoal (CC) of oak wood origin was studied in comparison with an activated carbon of coal origin. The adsorption capacity for Pb(II) of the non-activated charcoal increased significantly with deceasing particle diameter, whereas the activated carbon (AC) exhibited approximately constant capacity for Pb(II) adsorption as a function of particle size. Adsorption to the ashes prepared from the non-activated charcoal and the activated carbon was also investigated to examine the role of mineral ash. Although the ash from the activated carbon did not show any Pb(II) adsorption, the ash from the charcoal was very effective for Pb(II) adsorption. Furthermore, Pb(II) was hardly adsorbed when the ash was removed from the non-activated charcoal by acid treatment. Based on the results, the ...
The isotherms, kinetics and thermodynamics of Cd(II), Zn(II) and Pb(II) biosorption by Penicillium simplicissimum were investigated in a batch system. The effects of pH, initial metal ions concentration, biomass dose, contact time, temperature and co-ions on the biosorption were studied. Adsorption data were well described by both the Redlich-Peterson and Langmuir model. Chemical ion-exchange was found to be an important process based on free energy value from Dubini-Radushkevich isotherm for all metal ions. The results of the kinetic studies of all metal ions at different temperature showed that the rate of adsorption followed the pseudo second-order kinetics well. The thermodynamics constants {delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o} of the adsorption process showed that biosorption of Cd(II), Zn(II) and Pb(II) ions on Penicillium simplicissimum ...
The author discusses the formulation and application of the theory of quasi-catastrophes for the behaviour and properties of tachyons. This approach assists in the interpretation of experiments where tachyons may be involved. (W.D.L.).
In this study, the influence of Beryllium (Be) content on the fracture behaviour of Al?15%Mg2Si composite was investigated. The results showed an increase in mechanical properties with increasing of Be content. The stress?strain curves of samples showed a same category of serrations reflecting non-uniform deformation. Scanning electron microscopy was employed to examine the crack nucleation and fracture model. The results indicate that Al?15%Mg2Si composite shows different behaviours of crack initiation and fracture for samples with and without Be. Differences observed in the fracture behaviour were attributed to microstructural changes as well as morphological aspects of primary Mg2Si particles.
Securing the co-operation of persons supplying information required for medical statistics is essentially a problem in human relations, and an understanding of the motivations, attitudes, and behaviour...Full Text Available
BackgroundMovement regularities are inherently present in automated goal-directed motions of the primate's arm system. They can provide important signatures of intentional behaviours...Full Text Available
Fitness, (biometric measurements, reproduction) and behaviour that are ecologically relevant biomarkers in assessing the quality of estuarine sediments were studied by comparing the responses of the polychaete worm Nereis diversicolor - a key species in estuaries - along a pollution gradient. Intersite differences were shown for all the measured parameters: size-weight relationships, energy reserves as glycogen and lipids, sexual maturation patterns, total number of oocytes per female, total and relative fecundity, burrowing behaviour. The physiological and behavioural status of N. diversicolor was consistently disturbed in the larger, most contaminated estuaries (Loire and Seine, Fr.) compared to reference sites (Bay of Bourgneuf, Goyen estuary, Fr.). Many classes of potentially toxic che...
Abstract:- In recent years, the study of polymer/clay nanocomposites has attracted major research and commercial interests due to their superior mechanical and thermal properties to those of the neat polymers. Numerical modelling is an advantageous approach to understand the material behaviour. In this work a symmetric two dimensional finite element model is developed to simulate the fully exfoliated Polymer/Clay nanocomposite behaviour and evaluate its- before stress stress-strain curve. The Nylon 66/Clay in this study has a nonlinear elastic behaviour. The influence of volume fraction and aspect ratio of clay platelet (defined as the ratio of the particle length to the particle thickness) on the tensile behaviour of exfoliated Nylon 66/clay nanocomposite is investigated with the aid of n...
Maternal stress during pregnancy, particularly that combined with low socioeconomic status (SES), has been linked to an increased risk for impaired behavioural and emotional development and affective disorders in children. In animal models, acute periods of prenatal stress have profound effects on hypothalamo-pituitary-adrenal (HPA) function and behaviour. However, few studies have determined the impact of chronic exposure to stress in animal models. The objective of this study was to determine the effects of chronic maternal stress (CMS) during the 2nd half of pregnancy and nursing on growth, locomotor behaviour and HPA axis function in juvenile guinea pig offspring. Pregnant guinea pigs were exposed to a random combination of variable stressors every other day over the 2nd half of gestat...
With publication the fire design rules of the Eurocode and the national application documents (NAD) for the first time also calculation methods of constructive structural fire protection are available. This dimensioning of components and structures in fire case is based on the normal temperature design on Eurocodes and can be applied in the future as alternative to the classical fire design method of the German standard DIN 4102 part 4. In this contribution a view of the proof procedures of the Eurocode fire protection parts and the arrangements of the NADs is given as soon as the application of these fire design rules in Germany is described. (orig.) [German] Mit der Veroeffentlichung der Eurocode-Brandschutzteile als Vornormen und der zugehoerigen nationalen Anwendungsregelungen (NAD) als DIN-Fachberichte stehen erstmals auch rechnerische Nachweisverfahren ...
The competitiveness of a new nuclear plant vs. a new oil or gas fired combined cycle plant or a coal fired plant in East-Asia, is reviewed in the paper. Both the nuclear and the fossil fired plants are evaluated as either utility financed or independent power producer (IPP) financed. Two types of advanced light water reactors (ALWRs) are considered in this paper, namely evolutionary ALWRs (1200 MWe size) and passive ALWRs (600 MWe class). A range of capital and total generation costs for each plant type is reported here. The comparison centers on three elements of overall competitiveness: generation costs, hard currency requirements, and employment requirements. Each of these aspects is considered perspective. Year-by-Year generation cost history over the plant lifetime is shown in some cases. It is found here that a utility financed evolutionary and passive ALWRs are broadly competitive with an IPP financed gas ...
Those areas in California where synthetic fuel-fired power plants could be sited in the 1990 time frame, from an air quality perspective were identified. The synfuel-fired power plants considered in this new study were 500 MW methanol-fired combined cycle (MFCC) and 500 MW integrated gasifier combined-cycle (IGCC) units. For comparison purposes, 500 MW direct coal-fired boilers and 500 MW natural gas-fired combined-cycle units were also considered. The study provides an approximation, for planning purposes, of a reasonable limit of the state's power plant siting capacity, given the plant types and sizes, conditions, and assumptions specified. The study shows that local emission limitations many times preclude certain types of power plants even when they are equipped with Best Available Control Technology (BACT) as required by NSR regulations. This study also shows that 4000 ...
Smoke management in buildings during fire events often uses mechanical ventilation systems to maintain smoke layer elevation above a safe evacuation path. Design of these systems requires accurate correlations for the smoke production rate of the buoyant fire plume. One design issue is the smoke production rate of fire plumes which spill out from a fire compartment, under a balcony and up through an atrium or other large volume. Current engineering correlations for these balcony spill plumes are based on a combination of one-tenth scale test data and theoretical analysis. Questions have arisen over the suitability of these correlations for real-scale designs. A combined program of full-scale experimentation and CFD modeling is being conducted to analyze the accuracy of these correlations. A full-scale experimental facility was constructed with a 5 m by 5 m by 15 m fire compartment ...
Smoke management in buildings during fire events often uses mechanical ventilation systems to maintain smoke layer elevation above a safe evacuation path. Design of these systems requires accurate correlations for the smoke production rate of the buoyant fire plume. One design issue is the smoke production rate of fire plumes which spill out from a fire compartment, under a balcony and up through an atrium or other large volume. Current engineering correlations for these balcony spill plumes are based on a combination of one-tenth scale test data and theoretical analysis. Questions have arisen over the suitability of these correlations for real-scale designs. A combined program of full-scale experimentation and CFD modeling is being conducted to analyze the accuracy of these correlations. A full-scale experimental facility was constructed with a 5 m by 5 m by 15 m fire compartment ...
In this paper we present the results of our analyses of multidiurnal low-resolution Moderate Resolution Imaging Spectroradiometer (MODIS) thermal data for coal fire-related thermal anomaly detection. Results are presented for data of the Jharia coal mining region of India. We combine three relatively new approaches: first, we use low-resolution MODIS data for coal fire area analyses, which has only been undertaken by a few authors. Second, we analyse data from four different times of day (morning, afternoon, evening and predawn) and for three different bands (MODIS bands 20, 32 and a ratio thereof); and third, we use an unbiased automated algorithm for thermal anomaly extraction of local thermal anomalies. The MODIS data analysed stem from the years 2001 and 2005. In 2001, MODIS data were ...
Preliminary plans for the 90 to 100-MW coal-fired combined cycle plant due to be built by a team headed by Southern California Edison and Texaco in the mid-1980s are reviewed. The basic operating goals call for having a gasifier with a 1,000 ton coal capacity per day feeding a 70-MW turbine which then provides waste heat to run a 30-MW steam turbine. Texaco will have responsibility for the gasifier part of the facility with the turbine-generator vendor charged with providing both gas and steam turbine equipment. If the 100-MW demonstration plant achieves 32 to 33% design efficiency, then a commercial plant with expansion turbines and steam reheat should hit 38% and require 20 to 30% less water than a conventional coal fired plant.
We study the spike statistics of neurons in a network with dynamically balanced excitation and inhibition. Our model, intended to represent a generic cortical column, comprises randomly connected excitatory and inhibitory leaky integrate-and-fire neurons, driven by excitatory input from an external population. The high connectivity permits a mean field description in which synaptic currents can be treated as gaussian noise, the mean and autocorrelation function of which are calculated self-consistently from the firing statistics of single model neurons. Within this description, a wide range of Fano factors is possible. We find that the irregularity of spike trains is controlled mainly by the strength of the synapses relative to the difference between the firing threshold and the postfiring reset level of the membrane potential. For moderately strong synapses, we find spike statistics very similar to those observed in ...
Abstract: The recent National Academy of Sciences report on forensic sciences states that the study of fire patterns and debris in arson fires is in need of additional work and eventual standardization. We discuss a recently introduced method that can provide predicted evaporation patterns for ignitable liquids as a function of temperature. The method is a complex fluid analysis protocol, the advanced distillation curve approach, featuring a composition explicit data channel for each distillate fraction (for qualitative, quantitative, and trace analysis), low uncertainty temperature measurements that are thermodynamic state points that can be modeled with an equation of state, consistency with a century of historical data, and an assessment of the energy content of each distillate fraction...
The market potential for the fan atomized burner (FAB) in water and space heating applications was examined. The major findings of the study are as follows. (1). The FAB`s low-input capability allows development of oil-fired room heaters and wall furnaces, a new market area for oil heat. (2). Among conventional oil-fired products, furnaces will benefit most from the burner`s low input capability due to (1) their quick delivery of heat and (2) their more prevalent use in warmer climates and smaller homes. (3). The greatest potential for increased product sales or oil sales exists in the use of the burner with new products (i.e., room heaters). Sales of boilers and direct-fired water heaters are not likely to increase with the use of the burner. (4). Acceptance of the burner will be dependent on proof of reliability. Proof of better reliability than conventional burners would accelerate acceptance.
Remote sensing is the most practical method available to managers of fire-prone forests for quantifying and mapping fire impacts. Differenced Normalised Burn Ratio (?NBR) is among the most widely used spectral indices for the mapping of burn severity but is difficult to interpret in terms of fire-related changes in key biophysical attributes and processes. We propose to quantify burn severity as a change in the leaf area index (?LAI) of a stand. LAI is a key biophysical attribute of forests, and is central to understanding their water and carbon cycles. Previous studies have suggested that changes in canopy LAI may be a major contributor to ?NBR and to the composite burn index (CBI) that is frequently used in combination with the NBR to assess burn severity on the ground. We applied remote...
Fires and explosions have been identified as major potential hazards for Oil and Gas Floating Production Storage Offloading (FPSO) installations and pose risk to personnel, assets, and the environment. Current fire and explosion assessment (FEA) tools require physical effect modeling software and follows standards from API, ISO, and engineering practices. However, the tools are not specific to any particular system such as an FPSO, and do not provide comprehensive guidance for safety engineers to perform FEA. This paper discusses the development of a screening and comparison tool for FEA on FPSOs and the incorporation of an expert system into the tool. The results are computerized using MS Excel/VBA to provide a structured and comprehensive assessment on each equipment and module handling ...
Regular fuel reduction burning is an important management strategy for reducing the scale and intensity of wildfires in south-west Australian native forests, but the long term effects of this on tree and stand growth are not well understood. Five fire treatments, including application of frequent and infrequent low intensity burns, and 25?years of fire exclusion, were applied to small (4?ha) experimental plots in a low rainfall mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest to investigate the effects of these treatments on tree stem diameter growth, stand basal area increment and tree mortality. Mean tree stem growth measured over 20?years was lowest in the long unburnt treatment compared with the burn treatments, although surface soil nutrient levels were gener...
Operation and maintenance cost estimating methodologies for advanced coal-fired atmospheric circulating fluidized-bed and advanced natural gas-fired combined cycle electric power plants are presented. The purpose of these cost estimating relationships is for use in long range planning and evaluation of the economics of use of these technologies for electric power generation. Projected annual costs of reference plants at ten different sites in the United States, one in each of the ten DOE regions, are given as of 1989, and comparisons are made with existing technologies. A listing of a computer program implementing the methodologies is included. 14 refs., 4 figs., 13 tabs.
This paper reports that there are four combustion technologies upon which U.S. electric utilities are expected to rely for the majority of their future power generating needs. These technologies are pulverized coal- fired combustion (PC); coal-fired fluidized bed combustion (AFBC); coal gasification, combined cycle systems (CGCC); and natural gas-fired combined cycle systems (NGCC). The engineering and economic parameters which affect the choice of a technology include capital costs, operating and maintenance costs, fuel costs, construction schedule, process risk, environmental and site impacts, fuel efficiency and flexibility, plant availability, capacity factors, timing of startup, and the importance of utility economic and financial factors.
Australian electricity markets and natural gas markets are undergoing rapid reform. Choosing among electricity generation modes is a key issue. Such choices are affected by expectations about the future structure of these markets and future technologies, and how they affect costs and emissions. In the research reported in this paper, the MARKAL model of the Australian energy system is used to evaluate the competitive position of natural gas fired combined cycle gas turbines (CCGTs) in the energy sector as a whole. Competing in the sector are large-scale electricity generation technologies such as refurbished existing coal fired stations and advanced forms of coal fired generation. The modelling incorporates new data on electricity supply technologies and options.
This paper describes research and development presently being conducted on oil-fired space and tap water heating systems by the Advanced Combustion Technology Group, CCRL/ERL/CANMET, in Ottawa, Canada. The presentation will focus on R&D activities at CCRL in support of the Canadian Oil Heat Association (COHA) and of the energy policy initiatives of Natural Resources Canada. Progress will be reported on activities to develop suitable oil-fired integrated systems to satisfy the low energy demands of new homes. The utilization of fuzzy logic-based control heating systems including fan coils for a complete range of old and new North American housing will be discussed. Additional activities to be discussed in the presentation will relate to the development of appropriate seasonal efficiency standards for complex integrated space/water heating systems, as well as an evaluation of alternative sidewall venting technologies and their implications ...
Aqueous solutions of Al/sub 2/(SO/sub 4/)/sub 3/ (1.05 g/100 ml), AlCl/sub 3/ (0.82 g/100 ml) and Ca(OH)/sub 2/ slurry (0.94 g/50 ml) were mixed in various volume ratios and passed through a filter. White cakes left on the filter consisted mainly of ettringite (6CaO.Al/sub 2/O/sub 3/.3SO/sub 3/.32H/sub 2/O). The cakes were then calcined at various temperatures of 300/sup 0/ -- 1000/sup 0/C for 30 and 60 min and pulverized to 80 -- 200 mesh powders. The adsorption capacity of the powders for U(VI) ions dissolved in aqueous solutions was determined by immersing 0.100 g of their powders in 50 ml of the aqueous solution containing 100 ppm of U(VI) ions mainly in the form of (UO/sub 2/(CO/sub 3/)/sub 3/)/sup 4 -/ for 2 hours. The results obtained were summarized as follows. 1) Among the powders prepared, those of the oxide compositions, 2.9CaO.Al/sub 2/O/sub 3/.1.4SO/sub 3/ and 2.5CaO.Al/sub 2/O/sub 3/.1.2SO/sub 3/, all fired at 500/sup 0/C or 600/sup 0/C showed high ...
An exact cosmological solution of Einstein's equations which has time-dependent rotation is presented. The t-constant sections are of Bianchi type II. The source of this geometry is a fluid which has not been thermalized. (Author).
Exposure of albumin to Cu(II) (10-100 microM) and ascorbate (0.1-2 mM) results in extensive molecular modifications, indicated by decreased fluorescence and chain breaks. The rate of utilization of...Full Text Available
ObjectivesThe updated Rome III criteria for pediatric functional gastrointestinal disorders (FGIDs) include new FGID categories and changes to the Rome II criteria...Full Text Available
Interleukin 2 (IL-2) and B-cell growth factors I and II (BCGF I and BCGF II) are lymphokines produced by T cells that play a major role in T- and B-cell cooperation. Peripheral blood lymphocytes from...Full Text Available
In this article are presented main results on electric potential investigations in stellarator/torsatron TJ-II and tokamak T-10 in a comparable regimes of device operation.
Aminopeptidase II, one of the two major aminopeptidases in the giant alga Chara australis, was partially purified. Its molecular weight was estimated to be about 80,000 by gel permeation...Full Text Available
New palladium(II) and platinum(II) complexes of saccharinate (sac), trans-[Pd(py)"2(sac)"2] (1), cis-[Pt(py)"2(sac)"2] (2), trans-[Pd(3-acpy)"2(sac)"2] (3) and cis-[Pt(3-acpy)"2(sac)"2] (4) (py=pyridine and 3-acpy=3-acetylpyridine) have been synthesized. Elemental analysis, UV-Vis, IR, NMR and TG/DTA characterizations have been carried out. The structures of 1-4 were determined by X-ray diffraction. The palladium(II) and platinum(II) ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of py or 3-acpy, forming a distorted square-planar geometry. The palladium(II) complexes (1 and 3) are trans isomers, while the platinum(II) complexes (2 and 4) are cis isomers. The mononuclear species in the solid state are connected by weak intermolecular C-H...O hydrogen bonds, C-H...@...
BackgroundThe binding of peptide fragments of antigens to class II MHC is a crucial step in initiating a helper T cell immune response. The identification of such peptide epitopes...Full Text Available
The aim of this article was to investigate the interactions of metal cations in aqueous solutions with the biomass of the freshwater macroalga Vaucheria sp. This problem is important when elaborating new applications of biosorption, e.g. the production of mineral feed additives for livestock from the biomass of algae enriched with microelement ions. Potentiometric titration was applied as a quick and cheap screening test to search for new efficient biosorbents. It revealed a variety of functional groups capable of cation exchange on the macroalgal surface, including carboxyl, phosphate, hydroxyl or amino groups. Fourier transform infrared spectroscopy on natural and chromium-loaded Vaucheria sp. confirmed that carboxyl groups played a dominant role in the biosorption. The study also showed that Ca(II), Na(I), K(I), and Mg(II) ions were released from the biomass after biosorption of Cu(II), Mn(II), ...
BackgroundPromoter region plays an important role in determining where the transcription of a particular gene should be initiated. Computational prediction of eukaryotic Pol II promoter...Full Text Available
Rotazyme II, which is a shorter version of Rotazyme (less than 3 h), was compared with electron microscopy and Rotazyme for sensitivity and specificity on 229 human stool specimens. Compared with electron...Full Text Available
The biosorption of lead (II) and copper (II) ions, single component and binary systems, by dried P. putida was investigated in a batch system. The effects of initial pH, temperature, initial single and binary mixture concentrations on the biosorption kinetics and equilibrium uptake of each component, both single and binary mixtures were investigated. The bacterial biomass exhibited the highest single and binary lead (II) and copper (II) ions uptake capacity at 25 and 30 deg. C, respectively, the initial pH value of 5.5 and at the initial metal ions concentration of 100 mg dm{sup -3}. The Freundlich and Langmuir adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated at different temperatures. Adsorption data were well described by the Langmuir model, although they could be modeled by the Freundlich equation. The thermodynamics ...
BackgroundPerfluorocarbons (PFC) are used to improve gas exchange in diseased lungs. PFC have been shown to affect various cell types. Thus, effects on alveolar type II (ATII) cells...Full Text Available
ATP-binding cassette A3 (ABCA3) is a lipid transport protein required for synthesis and storage of pulmonary surfactant in type II cells in the alveoli. Abca3 was conditionally deleted...Full Text Available
Cytokinesis in animal and fungal cells utilizes a contractile actomyosin ring (AMR). However, how myosin II is targeted to the division site and promotes AMR assembly, and how the AMR coordinates with...Full Text Available
Anaerobic reactions of Rhus vernicifera laccase and its type-2 copper-depleted derivatives with hexacyanoferrate(II) were investigated by absorption and e.s.r. spectroscopy. When native laccase was...Full Text Available
Photobilirubin II, a stereoisomer of bilirubin, binds to human serum albumin at a single binding site (K = 2.2 x 10(6)M-1), presumably the high-affinity bilirubin-binding site. Binding in the secondary...Full Text Available
The identification of MHC class II restricted peptide epitopes is an important goal in immunological research. A number of computational tools have been developed for this purpose, but there is a lack...Full Text Available
In this work, the thermodynamic behaviour of single-stage horizontal spray coolers with one or more spray levels is experimentally examined. Further, a spray cooler calculation model was developed, in order to describe the processes and to make a comparison of the results of calculation and measurement. The state of the mine climate and the cold water are taken as the thermodynamic reference. (orig.).
In this study, deformation modes and precipitations have been characterized in test pieces made of alloy 800, grade 2 hyper-hardened state and age-conditioned for 3000 h at 550/sup 0/C, used for steam generator tubes of the Super Phenix Reactor, after continuous fatigue and fatigue-relaxation tests in the oligocyclic range. This microstructural study has provided an interpretation of the fatigue behaviour of the material.
This study presents the results of an 18-year long investigation of pipe deterioration in cyclone slag slurry transport. The goal was to study pipe behaviour in this extremely abrasive service and select an optimum piping material. Comparisons are given for high quality alloy cast steel pipes and pipes alined with cast basalt rings marketed under the name Abresist.
This study presents the results of an 18-year long investigation of pipe deterioration in cyclone slag slurry transport. The goal was to study pipe behaviour in this extremely abrasive service and select an optimum piping material. Comparisons are given for high quality alloy cast steel pipes and pipes lined with cast basalt rings marketed under the name Abresist. Based on the results, thoughts are offered on the broader meanings of certain findings.
The effect of small misch metal additions (0.25 to 1 wt.%) on the corrosion behaviour of aluminium was studied through electrochemical polarization in 0.1 N inorganic and organic acids at room temperature. It has been observed that rare earth addition improves the corrosion resistance of aluminium. (orig.).
This book contains 10 lectures with the following subjects: On the effect of thermal pretreatment on the structure and creep behaviour of the alloy 800 H (V. Guttmann, J. Timm); Material properties of heat resistant ferritic and austenitic steels after cold forming (W. Bendick, H. Weber); Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress (H.J. Penkalla, F. Schubert); Creep behaviour of gas turbine materials in hot gas (K.H. Kloos et al.); Effect of small cold forming on the creep beahviour of gas turbine blades made of Nimonic 90 (K.H. Keienburg et al.); Investigations on creep fatigue alternating load strength of nickel alloys (G. Raule); Change of structure, creep fatigue behaviour and life of X20 Cr Mo V 12 1 (by G. Eggeler et al.); Investigations on thermal fatigue behaviour (K.H. Mayer et al.); Creep ...
The generating functional in which the residual gauge freedom has been broken is related to the conventional generating functional for QED in arbitrary dimension. Closed expressions which relate ordinary N-point Green functions to N-point Green functions in the different gauges are derived. The leading logarithmic behaviour of the electron propagator in three dimensions is thus obtained. It is argued that one should not ascribe much importance to the infrared behaviour of the fermion propagator in the context of confinement.
In this paper, we intend to formulate a new metaheuristic algorithm, called Cuckoo Search (CS), for solving optimization problems. This algorithm is based on the obligate brood parasitic behaviour of some cuckoo species in combination with the Levy flight behaviour of some birds and fruit flies. We validate the proposed algorithm against test functions and then compare its performance with those of genetic algorithms and particle swarm optimization. Finally, we discuss the implication of the results and suggestion for further research.
... Screening Adjudication Monitoring Applicants of Information Behavior II I Conducting Investigations ... Applicants of Information Behavior Conducting ...
Titanate nanotubes were hydrothermally synthesized and their adsorption performances for lead(II) ion removal were studied. The results showed that titanate nanotubes ruptured in the adsorption process resulting in two distinct adsorption stages, thus achieving a maximum adsorption capacity of 3.752mmolg^-^1 of lead(II). Furthermore, it was found that the regeneration of titanate nanotubes loaded with the lead(II) ions can be readily achieved using the saturated EDTA disodium salt aqueous solution, thereby avoiding the trouble of disposal of adsorbent. The adsorption mechanism was also discussed in detail.
The interaction between N-donor adsorbates such as ammonia and pyridine with Cu(II)-exchanged montmorillonite, beidellite, flourohectorite into smectite clays has been studied by electron spin resonance. Cu(II) cations exchanged into smectites coordinate five ammonia or pyridine molecules in beidellite, four ammonia of pyridine molecules in hydroxyhectorite. Thus, the Cu(II) cations bound to the interior surfaces of these smectite clays constitute strong Lewis acid sites. 26 refs., 7 figs., 1 tab.
This report gives the results of a survey of operational flue gas desulfurization (FGD) systems on coal-fired utility boilers in the United States. The FGD systems installed on Units 1 and 2 at the Bruce Mansfield Station of the Pennsylvania Power Company...
Test firings of 120-mm rounds were performed to characterize effects due to the combustible cartridge cases used. Comparisons were made between measured ballistic parameters, especially gas pressures, and those predicted by computerized simulation calcula...
The Bureau of Mines and ASARCO Inc. entered a cooperative agreement to determine the feasibility of producing copper matte in an electric furnace from blends of copper concentrate similar to those currently smelted in a gas-fired reverberatory system at A...
Limestone slurry needs to move efficiently through a complex process, meaning that selecting the right pumps and valves is critical. The article discusses factors to consider in selecting pumps and values for flue gas desulfurization process in coal-fired power plants. 2 photos.
A schematic diagram of the decision making process for air pollution control equipment for the conversion of a fossil-fired generating unit from oil to coal is presented and explained.
The staff of the Spent Fuel Project Office at the U.S. Nuclear Regulatory Commission undertook the investigation and thermal analysis of the Baltimore tunnel fire event. This event occurred in the Howard Street tunnel, in Baltimore, Maryland, on July 18, 2001. The staff was tasked with assessing the consequences of this event on the transportation of spent nuclear fuel. This paper describes the staff's coordination with the following government and laboratory organizations: the National Transportation Safety Board (NTSB), to determine the details of the train derailment and fire; the National Institute of Standards and Technology (NIST), to quantify the thermal conditions within the tunnel; the Center for Nuclear Waste Regulatory Analysis (CNWRA), to validate the NIST evaluations, and the Pacific Northwest National Laboratory (PNNL), to assist in the thermal analysis. The results of the staff's review and analysis efforts are ...
Human beings are confronted with another grievous disaster - coal fire. The monitoring on underground coal bed combustion relied on drilling supervising in the past, but this method is not good. By taking the coal fire of Gulaben mine in Inner Mongolia Autonomous Region as an example, the monitoring methods of underground coal bed combustion were explored based on the hyperspectra and high-resolution remote sensing technology. By employing the OMIS imaging apparatus developed by Shanghai Institute of Technical Physics of Chinese Academy of Sciences, the airborne hyperspectral images and the characteristic spectra of different types were obtained and the temperature was measured synchronously on the ground. Then according to the correlation of DN value of the thermal infrared band and surface temperature, the image information was processed, the spectral features were analyzed, and the surface temperature retrieval model was built. Finally, by ...
Sep 28, 2011 ... Source: Flagstaff, AZ: Northern Arizona University. 87 p. Thesis. Description: High severity wildfires have been increasing across southwestern ...
This article puts the case for coal fired combined cycle gas turbine (CCGT) power plants. The need to gasify the coal for the CCGT, use of fluidised bed combustors or gasification systems, the difference in prices of coal and natural gas, and coal and natural gas reserves are discussed. (UK)
The aim was to investigate conditions relating to the substitution of natural gas for part of the amount of cinders previously used as fuel in an existing cupola furnace used in an iron foundry. The process of retrofitting is described. The principle solution is that four gas burners are placed symmetrically around the furnace immediately above the melting zone. They are mounted in separate fire boxes in such a way that they point downwards in order to prevent the fire box being filled with materials from the furnace, which would cause damage to the burners. The burners are continuously controlled to produce an output of 720 - 2620 kW and with 0.5 - 1.5 excess air. This solution was successful although it was found necessary (in order to achieve a satisfactory quality of resulting molten material) to add extra cinders to the furnace resulting in a reduction of only 9% of total cinders used, instead of the hoped-for 15%. The melting temperature ...
An investigation was conducted to determine the cause of coating residue found in the test gun chambers during qualification firing of 120-mm combustible cartridge case (CCC) ammunition for the MlAl/A2 main battle tank. The CCC is coated with a clear epox...
Rapid place encoding by hippocampal neurons, as reflected by place-related firing, has been intensely studied, whereas the substrates that translate hippocampal place codes into behavior have received...Full Text Available
A fireplace door assembly having doors pivotally mounted on a frame to be mounted on the opening of a fireplace. The doors are mounted on hinges that provide adjustment along a vertical axis of rotation and the front of the frame. An adjustable fire resistant gasket is used for an air seal. A gravity operated latch is provided to maintain the door in a closed position.
The report details the results of a series of large-scale experiments where small coal fires were used to ignite conveyor belting at air velocities ranging from 0.76 m/s to 6.1 m/s. In the tests, electrical strip heaters imbedded within a pile of coal were used to heat the coal to a point of flaming ignition. The flaming coal subsequently ignited conveyor belting located approximately 5 to 10 cm above the coal pile. During the tests, temperature, CO, and smoke levels were continuously measured in order to determine both alarm time and level as the fire intensity progressed through the stages of smoldering coal, flame coal, and flaming coal plus flaming belt. Analysis of the data leads to certain conditions of air velocity and sensor alarm levels that are required for early detection of conveyor belt entry fires. Two nomographs are presented which define sensor alarm levels and sensor spacings as a function of belt entry ...
Externally Fired Combined Cycles (EFCCs) can increase the amount of electricity produced from ash bearing fuels up to 40%, with overall powerplant efficiencies in excess of 45%. Achieving such high efficiencies requires high temperature-high pressure air heaters capable of driving modern gas turbines from gas streams containing the products of coal combustion. A pilot plant has been constructed in Kennebunk, Maine to provide proof of concept and evaluation of system components. Tests using pulverized Western Pennsylvania bituminous coal have been carried out since April, 1995. The ceramic air heater extracts energy from the products of coal combustion to power a gas turbine. This air heater has operated at gas inlet temperatures over 1,095 C and pressures over 7.0 atm without damage to the ceramic tube string components. Stable gas turbine operation has been achieved with energy input from the air heater and a supplementary gas fired combustor. ...
This paper describes the test results on high-temperature strength properties of fire resistant steel(FR steel) for building, the formulation, and the examples of application to member tests and actual buildings. Because of its components and manufacturing method, FR steel excels in strength at elevated temperature due to precipitation and dispersion strengthening. Tests on high temperature properties of FR steel showed that every property such as strength, stress-strain curve, elastic modulus, and creep performance at high temperature was superior to those of conventional steels. Then, it was confirmed in the tensile tests at room temperature and high temperature after heat history that FR steel could be reused after fire. It was also found in the member tests that columns and beams of FR steel could support loadings equivalent to long-term allowable unit stress until the temperature rose up to 600 centigrade. Moreover, test results could be ...
The report, generated by a computerized data base system, presents a survey of operational and planned domestic utility flue gas desulfurization (FGD) systems, operational domestic particle scrubbers, and Japanese coal-fired utility FGD installations. It ...
The report discusses the capabilities of equipment vendors to supply and install the quantity of flue gas desulfurization systems required to meet alternative standards for coal-fired steam generators. It analyzes limiting factors affecting supply capabilities (such as the availa...
Several theories have proposed a functional role for synchronous neuronal firing in generating the neural code of a sensory perception. Synchronous neural activity develops during a critical...Full Text Available
A high-performance power system (HIPPS) is being developed. This system is a coal-fired, combined-cycle plant that will have an efficiency of at least 47 percent, based on the higher heating value of the fuel. The original emissions goal of the project was for NOx and SOx to each be below 0.15 lb/MMBtu. In the Phase 2 RFP this emissions goal was reduced to 0.06 lb/MMBtu. The ultimate goal of HIPPS is to have an all-coal-fueled system, but initial versions of the system are allowed up to 35 percent heat input from natural gas. Foster Wheeler Development Corporation is currently leading a team effort with AlliedSignal, Bechtel, Foster Wheeler Energy Corporation, Research-Cottrell, TRW and Westinghouse. Previous work on the project was also done by General Electric. The HIPPS plant will use a high-Temperature Advanced Furnace (HITAF) to achieve combined-cycle operation with coal as the primary fuel. The HITAF is an atmospheric-pressure, ...
Coke-fired cupola furnaces were improved and made suitable for the production of high-quality casting melts by numerous additional devices. Moreover, they were equipped with environmental protection systems with numerous dust separation devices and afterb...
The US Department of Energy`s Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and also indicated favorable economics for replacement of oil- and gas-fired ...
The US Department of Energy's Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and also indicated favorable economics for replacement of oil- and ...
AbstractDendrites of cerebellar Purkinje cells (PCs) respond to brief excitations from parallel fibers with lasting plateau depolarizations. It is unknown whether these plateaus are local...Full Text Available
This report presents a study on the use of computerised, continuous remote monitoring systems for fire and explosive atmosphere safety in underground coal mines. The effects of these systems on the safety level in mines are investigated, and the relationship between mine safety regulations and computerised, continuous, remote monitoring is analysed.
This report presented an analysis of incidents gathered by the Canadian upstream oil and gas industry committee in relation to explosive atmospheres in wellbores, vessels, tanks, and piping systems. The aim of the report was to develop industry recommended practices for oil and gas industry fires and explosions. Two accident theory models were used to set out the relationships between hazards, defenses, and losses. Three levels of defenses were identified based on organizational, local workplace, and human factors. An organizational responsibility approach was used to examine the activities of key people with the system. Incidents were analyzed based on an expanded fire triangle used to identify fire and explosion hazards. The study showed that the ignition of hydrocarbons into the air was a factor in nearly 50 per cent of the incidents. A lack of understanding of liquid-hydrocarbon properties was demonstrated in incidents ...
Tachyons fired into and absorbed by rotating black holes can violate the second and third laws of black hole physics. It is suggested that apparent break-downs of these laws in astrophysical black holes can indicate the existence of cosmic tachyons. (author).
Dopaminergic neurons of the ventral midbrain fire high frequency bursts when animals are presented with unexpected rewards, or stimuli that predict reward. To identify the afferents that can...Full Text Available
Fuel treatments are being widely implemented on public and private lands across the western U.S. While scientists and managers have an understanding of how ... ...
Gas-fired combined cycle plant may be the norm when it comes to new plant but it comes in a variety of shapes and sizes. Samarinda uses aero-derivatives with the famous Rolls-Royce RB211 gas generator. (author)
A model has been developed in the recent past to predict fatigue crack growth (FCG) behaviour in the Paris-regime of various steels by employing low cycle fatigue (LCF) properties. The model forms its basis on the assumption that the cyclic damage process immediately ahead of a crack-tip, restricted in a small zone termed as process zone, is identical to those experienced in the LCF loading of a smooth specimen. Within the process zone, fatigue damage has been assumed in terms of product of stress and plastic strain which is analogous to the plastic strain energy density of the smooth specimen under fatigue loading. In this paper the model developed by Kujawski and Ellyin has been used to predict the FCG behaviour of an #alpha#-#beta# titanium alloy in the Paris-regime by employing the experimentally obtained LCF properties. The FCG behaviour thus theoretically predicted was compared with the experimentally determined FCG ...
Fitness, (biometric measurements, reproduction) and behaviour that are ecologically relevant biomarkers in assessing the quality of estuarine sediments were studied by comparing the responses of the polychaete worm Nereis diversicolor - a key species in estuaries - along a pollution gradient. Intersite differences were shown for all the measured parameters: size-weight relationships, energy reserves as glycogen and lipids, sexual maturation patterns, total number of oocytes per female, total and relative fecundity, burrowing behaviour. The physiological and behavioural status of N. diversicolor was consistently disturbed in the larger, most contaminated estuaries (Loire and Seine, Fr.) compared to reference sites (Bay of Bourgneuf, Goyen estuary, Fr.). Many classes of potentially toxic chemicals present in these estuaries most likely contribute to these impairments but food availability may act as a confounding factor, ...
Micropatterned surfaces with different chemical topographies were synthesised in order to investigate the influence of surface chemistry and topography on cell behaviour. The microstructured materials were synthesised by photoimmobilising natural Hyaluronan (Hyal) and its sulphated derivative (HyalS), both adequately functionalised with a photorective moiety, on glass substrates. Four different grating patterns (10, 25, 50 and 100 {mu}m) were used to pattern the hyaluronan. The micropatterned samples were analysed by Secondary Ions Mass Spectrometry, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy to investigate the chemistry and the topography of the surfaces. The spectroscopic and microscopic analysis of the microstructured surfaces revealed that the photoimmobilisation process was successful, demonstrating that the photomask patterns were well reproduced on the sample surface. The influence of chemical topographies on the cell ...
Studies of the effectiveness of operant, relaxation, cognitive, and multimodal behavioural approaches to the treatment of chronic benign pain other than headache were evaluated. In general, the quality of the studies was poor, and most investigations lacked appropriate and adequate control conditions, outcome measures, and/or follow-ups. While outcome reports for all four behavioural treatments have been mainly positive, few data were found which conclusively demonstrate that any of the approaches are effective or that they are the treatment of choice. The data do, however, imply that behavioural approaches may help patients lead more normal and productive lives. Specifically, the literature suggests that: (1) the operant method leads to increased activity levels and decreased pain and drug intake, (2) the relaxation approach results in decreased EMG levels and some pain reductions, (3) the cognitive techniques are ...
We report the of the existence of RV Tauri stars in the Large Magellanic Cloud (LMC). This class of variable star has hitherto been unidentified in the Magellanic Clouds. In light and color curve behavior the RV Tauri stars appear to be an extension of the Type II Cepheids to longer periods. A single period-luminosity-color relationship is seen to describe both the Type II Cepheids and the RV Tauri stars in the LMC.
Incorporation of /sup 32/P from (gamma-32P)ATP into tyrosine residues of the insulin-like growth factor (IGF)-II receptor was observed in a Triton X-100-insoluble fraction of rat adipocyte plasma membranes. IGF-II receptor phosphorylation proceeded to a stoichiometry of approximately 0.5 mol of phosphate/IGF-II binding site after 10 min of incubation at 4 degrees C. A Km for ATP of 6 microM was calculated for this phosphorylation reaction. Addition of IGF-II caused an approximately 2-fold increase in tyrosine phosphorylation of the IGF-II receptor in this preparation. In contrast, phosphorylation of angiotensin II by the Triton X-100 washed membranes was not stimulated by IGF-II. Incubation of purified receptor immobilized on IGF-II agarose or of receptor-enriched low density microsomal membranes with (gamma-32P)ATP did ...
Fragrance mix II (FM II) is a relatively new screening marker for fragrance contact allergy. It was introduced in the patch test baseline series in Denmark in 2005 and contains six different fragrance chemicals commonly present in cosmetic products and which are known allergens.
Fatty acid biosynthesis is crucial for all living cells. In contrast to higher organisms, bacteria use a type II fatty acid synthase (FAS II) composed of a series of individual proteins, making...Full Text Available
This study reports on the physical-chemical behaviour of swelling di-octahedral clays (smectites) and their interaction with aqueous solutions and bacteria (Shewanella putrefaciens). Experimental results are presented for compacted clays, hydrated under confined volume conditions, using a new type of reaction-cell (the 'wet-cell' of Warr and Hoffman, 2004) that was designed for in situ X-ray diffraction (XRD) measurement. For comparison, dispersed clay systems were studied using standard batch solutions subjected to varying degrees of agitation. The combination of time-dependent in situ XRD measurements with gravimetric measurements and calculated diffraction patterns using the CALCMIX software (Plancon and Drits, 1999) allowed to successful quantification of the dynamics of water uptake and storage. This analytical procedure combined with published water vapour adsorption data enabled determination of the abundance of structured water layers, ...
Data on the postfire dynamics of soil properties in the foci of Siberian moth population outbreaks are considered. It has been shown that controlled fires set in pest-defoliated forests result in the loss of approximately 75% of carbon and 50% of nitrogen from the forest litter through their emission into the atmosphere and in the enrichment of the upper soil horizons with potassium and phosphorus (this concerns both total and movable forms). Microbiological processes in the organogenic horizon undergo significant transformation, the density of microarthropods decreases, and the abundance of mites becomes hundreds of times lower. PMID:15354965
Describes the wastes produced and the waste disposal methods used at BEWAG power plants. Wastes covered include fly ash, fluidized bed ash, gypsum from flue gas desulfurization and evaporation residues. Disposal methods include using ashes and gypsum to make building materials. Despite many years of experience in the utilization and disposal of residues from coal-fired power stations BEWAG have not encountered any disposal problems. 5 tabs.
Investigations were conducted at Los Alamos National Laboratory to quantify the extent of migration of depleted uranium away from firing sites. Extensive sampling of air particles, soil, sediment, and water was conducted to establish the magnitude of uranium contamination throughout one watershed. The uranium source term was estimated, and mass balance calculations were performed to compare the percentage of migrated uranium with original expenditures. Mass balance calculations can be powerful in identification of the extent of waste migration and used as an aid in planning future waste investigations.
Taiwan`s LNG consumption is planned to rise more than threefold over the next four years as medium-term plans to develop power generation facilities increasingly rely on gas-fired combined-cycle stations to avoid the threat of power shortages. State-run Taiwan Power Company (Taipower) expects its LNG consumption to rise from 1.1 mn tonnes in 1996 to 3.4 mn tonnes in the year 2000. By then the first of several gas-fired private power stations is expected to enter service, further increasing Taiwan`s total LNG requirement for power generation. (Author)
Time delay neural networks trained with the backpropagation algorithm are derived for the gun fire control system to correct the miss distance between a target and the projectiles from the gun. Its performance is compared to optimum linear filter based on minimum mean square error [R.E. Kalman, A new approach to linear filtering and prediction problems, J. Basic Eng. 82D (1960) 35-44.]. The structure of the proposed neural controller is described and performance results are shown.
A modified variable structure interacting multiple model (M-VSIMM) estimator for complex hybrid maneuver target tracking is presented. The M-VSIMM could potentially be applied to fire control systems (FCS) used on warships. Target model groups were designed using 3D dimensional dynamic target models. Optimal model group selection logic was proposed, contrary to the activation and termination logic in the original VSIMM. The system will respond faster with optimal model group selection logic. After performing simulations, the tracking performances of the Kalman, ?-?(-?), VDIE, IMM and M-VSIMM filters were compared under various maneuvering conditions.
Increasing demand for energy production with low impact on the environment and minimised fuel consumption can be met with high efficient coal fired power plants with advanced steam parameters. An important key to this improvement is the development of high temperature materials with optimised mechanical strength. Based on the results of more than ten years of development a coal fired power plant with an efficiency above 50 % can now be realised. Future developments focus on materials which enable an efficiency of 52-55 %. (orig.) 25 refs.
The Federal Republic of German (FRG) had uniquely strict emission legislation for particulates SO_2 and NO_X from fossil-fired power plants. The 13th Regulation to the Federal Emission Control Act required that by 1 July 1988 all large furnaces fired with solid or liquid fuels that would not be decommissioned by 1993 be retrofitted with SO_2 control technology. The emission limits are 15 per cent of the sulphur introduced with the fuel (400 mg/m"3 maximum) at thermal capacities above 300 MW. 1 ref., 9 figs, 15 bibliographies.
Results are reported from initial characterization tests on the environmental effects of the natural draft cooling tower of the Chalk Point Unit 3 oil-fired power plant located on the shore of Chesapeake Bay. Data are included on updraft air velocity, plume drift, and sea salt deposition in relation to meteorological conditions.
Some acylhydrazine derived ONO donor Schiff bases and their Co(II) and Ni(II) complexes have been prepared having the same metal ion (cation) but different anions. These synthesized metal(II) complexes have been characterized on the basis of their elemental analyses, magnetic moment, molar conductance, and IR and electronic spectral data. All of the Schiff base ligands function as tridentates and the deprotonated enolic form is preferred for coordination. In order to evaluate the effect of anions on the bactericidal activity, these synthesized complexes, in comparison to the uncomplexed Schiff bases have been screened against bacterial species., Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and the results are reported. PMID:18475936
High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723 K by using Eu{sub 2}O{sub 3} as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723 K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.
High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723 K by using Eu_2O_3 as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723 K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.
High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723K by using Eu2O3 as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.
We determined the chromosomal localization and structure of the gene encoding human type II inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205), an enzyme associated with cellular proliferation, malignant transformation, and differentiation. Using polymerase chain reaction (PCR) primers specific for type II IMPDH, we screened a panel of human-Chinese hamster cell somatic hybrids and a separate deletion panel of chromosome 3 hybrids and localized the gene to 3p21.1{yields}p24.2. Two overlapping yeast artificial chromosome clones containing the full gene for type II IMPDH were isolated and a physical map of 117 kb of human genomic DNA in this region of chromosome 3 was constructed. The gene for type II IMPDH was localized and oriented on this map and found to span no more than 12.5 kb.
In this study we compared various maturity dependent aromatic, steroid and triterpenoid hydrocarbon ratios in bitumens that are freely extractable from sedimentary rocks (Bitumen I) with those in second extracts that comprised hydrocarbons closely associated with the kerogen/mineral matrix (Bitumen II). Bitumen II was released through kerogen isolation and demineralisation using HCl and HF/H3BO3. The samples studied, although of similar age, come from different localities. They represent a range of facies and two kerogen types (II and III), and all were deposited under marine conditions. The results show that the more stable b isomers of methylnaphthalene (MN) and methylphenanthrene (MP) are relatively more abundant in Bitumen II. The difference between the methylnaphthalene ratio (MNR) of...
In this study, the biosorption of Cd(II), Ni(II) and Pb(II) on Aspergillus niger in a batch system was investigated, and optimal condition determined by means of central composite design (CCD) under response surface methodology (RSM). Biomass inactivated by heat and pretreated by alkali solution was used in the determination of optimal conditions. The effect of initial solution pH, biomass dose and initial ion concentration on the removal efficiency of metal ions by A. niger was optimized using a design of experiment (DOE) method. Experimental results indicated that the optimal conditions for biosorption were 5.22 g/L, 89.93 mg/L and 6.01 for biomass dose, initial ion concentration and solution pH, respectively. Enhancement of metal biosorption capacity of the dried biomass by pretreatment with sodium hydroxide was observed. Maximal removal efficiencies for Cd(II), Ni(III) and ...
The radiation reduction of bis(1-ethylimidazole)tartratoplatinum(II) (EITPt(II)) complexes in methanol-water solution have been examined. The yields of Pt(I) depend on the presence of O{sub 2} in solutions as well as the dose applied. The rate constants of e{sub s}{sup -} scavenging by EITPt(II) and cis(diammine-1,1-cyclobutanedicarboxylato) platinum(II) (CBDCAPt(II)) have been determined by pulse radiolysis to be equal to 5.4 x 10{sup 9} and 6.4 x 10{sup 9} M{sup -1} s{sup -1}, respectively. The efficiencies of e{sub t}{sup -} scavenging by EITPt(II) and the rate of e{sub t}{sup -} photobleaching have also been determined in LiCl : H{sub 2}O : CH{sub 3}OH and MgCl{sub 2} : H{sub 2}O : CH{sub 3}OH glasses, respectively. (author).
This paper relates to a simple approach to the analysis of the behaviour of pool type LMFBR primary circuits in natural convection and to experimental work to support this approach. The primary application is the prediction of plant behaviour in decay heat removal conditions when depending on natural convection effects to cool the core. In formulating a mathematical model of the plant for this application, the main difficulty is the modelling of the large plena between the core and IHX and the IHX and the pump inlet. In a previous paper discussing CDFR behaviour after a reactor scram with total loss of power to the primary pumps, the first author described attempts to model the CDFR hot pool in a way which would be limiting in a pessimistic sense. The shortcomings of these attempts were reviewed and mention was made of an improved method then under development. Essentially, the improved model allowed for migration of hot ...
Executive summary 1. Few studies have to date explained consumer attitudes and purchase decisions with regard to genetically engineered food products. However, the increased marketing of genetically engineered food products and the considerable concern that consumers seem to express with regard to the technology call for the development of a theoretical basis for research into these issues. 2. The aim of the paper is to present three models which we have developed to explain consumer attitudes, buying behaviour and attitude change with regard to genetically engineered food products. All three models build on established consumer behaviour theory and on existing and comparable research in the field. 3. Consumer attitudes toward genetic engineering in food products are explained in an attitude model that builds on Fishbein's multiattribute attitude model. The model deviates from Fishbein's model in a number of ways: there is an explicit ...
A method for simplifying finite element models of structures having a beam-like global dynamical behaviour is presented. This method is based on the use of a general uniform beam finite element formulation. It takes into account both transverse shear effects and dynamical coupling between bending and torsion due to the fact that mass centres and shear centres do not always coincide. For that purpose, we develop a condensation method for reducing any shell model into an equivalent beam, as well as a technique for automatically identifying the corresponding set of beam parameters. The method is applied to several illustrate examples that demonstrate its ability to simplify finite element models for many kinds of sophisticated structures having a beam-like predominant behaviour.
AM-SC1 is a heat treatable magnesium alloy that has been specifically developed to achieve the elevated temperature strength and creep properties necessary for engine block applications. This paper describes the interrelationship between the microstructure and the mechanical properties of AM-SC1. The compressive and tensile strengths are relatively insensitive to temperature up to and including 450 K and the tensile yield behaviour deviates from a standard Hall-Petch relationship at grain sizes below 200 ?m. The microstructural features contributing to the creep resistance are both inter- and intra-granular in nature and are on length scales from nanometers to micrometers. The creep behaviour at 423 K and 450 K is diffusion controlled, with any contribution from the grain boundaries being negligible.
The present paper describes the investigation of the static and dynamic behaviour of an 20 kW pressure electrolyser. The suitability for a coupled operating regime with a wind power plant has been investigated. At first the static behaviour has been analysed. The share of oxygen in hydrogen gas is lower than 0.5 Vol%. But reaching the temperature limit of 80 deg C leads to a switch off of the electrolyser, accompanied by an increase of the oxygen share in hydrogen gas up to 1.3 Vol%. Therefore, an improvement of the cooling system is necessary. Secondly, the electrolyser was excited by different step signals for load changing and finally, the electrolyser has been controlled by the power output signal of the windmill. The investigation shows that the development of a direct coupled wind-hydrogen system will be only a small step. 3 refs.
Magnesium alloys show a high specific strength and are therefore increasingly used for light-weight constructions in transportation industry.{sup [1,2]} To predict the behaviour of the material under the influence of cyclic loading it is vital to understand the fatigue behaviour of magnesium alloys. Only when understood properly, it is possible to fully apply the potential weight reduction by using magnesium alloys. A very important aspect in fatigue of magnesium alloys is the influence of a corrosive media and elevated temperatures, of which both are relevant in automotive applications. These two factors tend to have deleterious effects on magnesium alloys and therefore also have to be considered in investigations on the fatigue behaviour of magnesium alloys. (Abstract Copyright [2004], Wiley Periodicals, Inc.)
Emeraldine base (EB) polymer?ZnO nanoparticles composite films has been synthesized by solution casting technique on ITO-coated glass substrate and characterized by XRD, FTIR and TEM for their structure and morphology. Dielectric behaviour of these composite films has been investigated in the very low frequency region to medium frequency region (1?kHz?1?MHz). The dielectric constant of the composite with 30% nanoparticles is almost one-tenth of the pure EB. The dielectric value becomes constant in the frequency region greater than 400?kHz. The change in dielectric behaviour of the composite is explained on the basis of multilayered interface formed between the ZnO nanoparticles and emeraldine chains. Nanoparticles have high energy surface which is responsible for the decrease of free volum...
This study looks for the presence of rational speculative bubbles in Real Estate Investment Trusts (REITs) using unit-root, variance ratio, duration dependence and regime switching regression tests. The regime switching method provides weak evidence of speculative bubble behaviour in both the mortgage and hybrid REITs sectors even though traditional econometric bubble tests do not provide evidence of rational speculative bubbles in all REIT markets. Findings suggest that price movement in mortgage and hybrid REITs may be induced by bubble-like behaviour of investors. This behaviour may be traced to the real estate market bubble. Our results provide evidence that the real estate bubble that started in early 2000 was transmitted into securitized real estate markets. A regime switching model ...
When backward time travel through wormholes is taken into account, classical physics loses its determinism and allows simulation of some quantum behaviours. We show how it is possible to simulate a non-local wavefunction reduction-type effect, i.e. we present a mechanical analogy for the collapse of the wavefunction of an entangled state of two removed particles. This situation can be seen as the simplest EPR situation, i.e. the situation where there is just one direction to measure along the spin (or the correlated properties). We present no rigorous results here, just a different point of view about something that is generally thought to be impossible: modelling a quantum indeterministic and non-local behaviour with a mechanical system.
In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of Alloy 800 ...
In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of Alloy 800 ...
The palladium(II) and platinum(II)complexes(where, (M(L){sub 2}X{sub 2}), M=Pd(II), Pt(II); L=isoxazole (isox), 3, 5-dimethylisoxazole(3, 5-diMeisox), 3-methyl, 5-phenylisoxazole(3-Me, 5-Ph-isox), and 4-amino-3, 5-di-methylisoxazole (4-ADI); X=Cl, Br) with isoxazole and its derivatives were investigated on antitumor activity by MM2 and EHMO calculation. Because for all the complexes the {sigma}MO energy level (E{sub {sigma}}{sub (M-X)} between d{sub x}{sup 2}{sub -y}{sup 2} orbital of central metal and p{sub x} orbital of halogen atom is less than {sigma}MO energy level E{sub {sigma}}{sub (M-N)} between d{sub x}{sup 2}{sub -y}{sup 2} orbital of central metal and p{sub x} orbital of N atom, without exception. And judging, from the lower E{sub {sigma}}{sub (M-X)} value in trans, the bonding strength was found to be weaker in trans isomer than in cis. For the Pd(II) and ...
Varying coordination modes of the Schiff base ligand H"2L [5-methyl-1-H-pyrazole-3-carboxylic acid (1-pyridin-2-yl-ethylidene)-hydrazide] towards different metal centers are reported with the syntheses and characterization of four mononuclear Mn(II), Co(II), Cd(II) and Zn(II) complexes, [Mn(H"2L)(H"2O)"2](ClO"4)"2(MeOH) (1), [Co(H"2L)(NCS)"2] (2), [Cd(H"2L)(H"2O)"2](ClO"4)"2 (3) and [Zn(H"2L)(H"2O)"2](ClO"4)"2 (4), and a binuclear Cu(II) complex, [Cu"2(L)"2](ClO"4)"2 (5). In the complexes 1-4 the neutral ligand serves as a 3N,2O donor where the pyridine ring N, two azomethine N and two carbohydrazine oxygen atoms are coordinatively active, leaving the pyrazole-N atoms inactive. In the case of complex 5, each ligand molecule behaves as a 4N,O donor utilizing the pyridine N, one azomethine N...
The biosorption characteristics of Pb(II) and Cd(II) ions from aqueous solution using the green alga (Ulva lactuca) biomass were investigated as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the metal ions by U. lactuca biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of U. lactuca biomass for Pb(II) and Cd(II) ions was found to be 34.7 mg/g and 29.2 mg/g, respectively. From the D-R isotherm model, the mean free energy was calculated as 10.4 kJ/mol for Pb(II) biosorption and 9.6 kJ/mol for Cd(II) biosorption, indicating that the biosorption of both metal ions was taken place by chemisorption. The calculated thermodynamic parameters ({delta}G{sup o}, ...
Although polybrominated naphthalenes (PBNs) are contaminants of the commercial fire retardant fireMaster BP-6, the individual PBN isomers have not been identified. In order to study PBNs possessing an analogous level of bromination to those found in fireMaster BP-6, three synthetic PBN mixtures, averaging 5.0, 5.3, and 5.6 bromines per naphthalene were synthetized and partially characterized. The PBN mixtures were administered to immature male Wistar rats and found to be potent inducers of cytochrome P-450-dependent monooxygenases. At the lowest dose tested, 30 mumol X kg-1, each PBN mixture caused maximal induction of benzo(a)pyrene hydroxylase activity. On the basis of enzyme activities, ligand-binding spectra and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the PBN mixtures were determined to be 3-methylcholanthrene-type inducers of cytochrome P-450 (P-448), resembling qualitatively the most toxic ...
The temperature dependence of the dislocation mobility threshold is investigated on the basis of a dislocation model suggested by Frenkel-Kontorova. The critical value is obtained for the stress/temperature, corresponding to the dislocation depinning from its equilibrium position. The universal behaviour of a barrier height at finite stress and temperature is revealed and investigated.
SummarySurvival requires the selection of appropriate behavioural responses in the face of danger. With respect to the threat of predation, both the decision to escape and the underlying...Full Text Available
BackgroundA key feature of a good general practice consultation is that it is patient-centred. A number of verbal and non-verbal behaviours have been identified as important to establish...Full Text Available
Analysis of results of an investigation into the structure of lithium salt aqueous solutions is presented. An anomaly in lithium ion behaviour in solutions at the structural level is noted. 40 refs., 3 tabs.
This section of the report is concerned with the study of the metallisation, oxidation and doping of materials which are of importance to the micro-electronics industry. The Van de Graaff accelerator and radioactive tracers are used for studying surface and sub-surface behaviour of these materials.
Solid molecular orthohydrogen exhibits orientational order at low temperatures. The orthohydrogen molecules, which are quadrupoles, order in the Pa3 structure. We have simulated this ordering, and explored the behaviour under dilution by spherical parahydrogen molecules.
Project ZEUS was designed to characterize the effects of long-term gamma irradiation on free-ranging meadow voles, and to determine the lowest level of radiation at which biological effects are discernible in the population. Behavioural tests are consider...
It has been predicted that geometrically similar animals would swim at the same speed with stroke frequency scaling with mass−1/3. In the present study, morphological and behavioural...Full Text Available
...Year nine students will be taught the importance of mateship in a bid to reduce risky behaviour and save lives as part of a school-based intervention program to be introduced in Queensland. 24.11.10 Safe sex saves schoolies from chlamydia The safe-sex message is failing to get ...
BackgroundHealthcare professionals can play a crucial role in optimizing the health status of patients with cardiovascular risk factors (abdominal obesity, high blood pressure, low...Full Text Available
Species that depend on ephemeral habitat often evolve distinct dispersal strategies in which the propensity to disperse is closely integrated with a suite of morphological, behavioural and physiological...Full Text Available
Mutations in SPTBN2, the gene encoding β-III spectrin, cause spinocerebellar ataxia type 5 in humans (SCA5), a neurodegenerative disorder resulting in loss of motor...Full Text Available
BackgroundMother-to-Child Transmission (MTCT) of HIV remains the main mode of acquisition of HIV in children. Transmission of HIV may occur during pregnancy, delivery or breastfeeding....Full Text Available
ObjectivesThe main objectives of this project are: 1. To determine whether nest-drifting behaviour allows helpers to maximise their indirect fitness in the paper wasp Polistes canadensis. Specifically, I will test a) whether nest-drifters apportion helping effort in relation to the productivity benefits of different nests (hypothesis 1a), and b) whether nest-drifters can adjust their investment in response to changes in the productivity payoffs of different nests (hypothesis 1b). 2. To determine [continued...]DescriptionDarwin's theory of natural selection predicts that organisms should act selfishly in order to pass on as many of their genes to the next generation as possible. The evolution of social behaviour is a paradox because it requires that some individuals forgo reproduction in order to help raise the offspring of others. Explaining the evolution of helping behaviour in animal societies has been a major focus for ...
Patent medicine vendors (PMVs) are a ubiquitous feature of the informal health sector in Nigeria. A previous study on healthcare-seeking behaviour of persons with chronic cough in southern Nigeria found...Full Text Available
Most superconductors are quite sensitive to irradiation defects. Critical temperatures may be depressed, critical currents may be increased, by irradiation, but other behaviours may be encountered. In compounds, the sublattice in which defects are created is of significant importance. 24 refs.
The three-dimensional (3-D), multiphase, computational fluid dynamic (CFD) code FLUENT is used to simulated two-phase flow behaviour in a CANDU header manifold under low (natural circulation) flow conditions. This behaviour was previously inferred from experimental data. The CFD simulations reported here are being used to support these inferences and to obtain a better understanding of phase distribution in the header manifold. The simulations seem to show that the vapor-water mixture models in the FLUENT code do not capture properly phase separation in the header and proper phase branching at the header-feeder connections that have been observed in experiments at low flows. The simulations using discrete-phase model in FLUENT, which tracks the pathlines of the individual vapor bubbles in the water continuum phase, show interesting, complicated and, in some cases, unexpected bubble trajectories from the point of injection of the bubbles at a ...
1. Interactions of pyrazole and ethanol were studied in three laboratory test procedures. They included sleeping time in mice, rotor rod balance in rats and lever pressing behaviour of rats. 2....Full Text Available
Vanadium doped manganese bi-oxide has been obtained from a solution containing both cations. The X-ray diffraction of this material indicates a rutile-type phase but the enlargement of some lines supports the existence of several lattice defects. Also the particle size of the doped material is significantly smaller than the one of the non-doped material obtained in the same conditions. The presence of pentavalent vanadium inside the lattice leads to a small amount of trivalent manganese. Electron microscopy shows the existence of defects which have a tendency of becoming well-ordered and to stabilize a sur-structure. At ambient temperature, the electrochemical behaviour of doped manganese bi-oxide is greatly improved when compared to the non-doped phase. This behaviour is due to the presence of numerous lattice defects and to the smaller size of crystallites. In polymer batteries, the behaviour is similar the one of the ...
Objectives:Despite its impact on health policy, the relationship between geographical proximity and health care seeking has received scant attention in the medical literature. This...Full Text Available
Typically, modern economics has steered away from the analysis of sociological and psychological factors and has focused on narrow behavioural assumptions in which expectations are formed on the basis...Full Text Available
Many animals use the spectral distribution of light to guide behaviour, but whether they have colour vision has been debated for over a century. Our strong subjective experience of colour and the fact...Full Text Available
The general objective of the International Seminars of Horizontal Steam Generator Modelling has been the improvement in understanding of realistic thermal hydraulic behaviour of the generators when performing safety analyses for VVER reactors. The main to...
The EMS effect is explained in the flucton model as a consequence of scale invariance violation. Nontrivial behaviour of the ratio between structural functions and production cross sections for lepton pairs for different nuclei at x > 1 is predicted.
BackgroundThere has been increasing interest in the ability of the internet to produce behaviour change. The focus of this study was to describe program exposure across three intervention...Full Text Available
BackgroundIt has been assumed that the unusual tail club of ankylosaurid dinosaurs was used actively as a weapon, but the biological feasibility of this behaviour has not been examined...Full Text Available
The modification of a Ford 7600 turbocharged diesel engine to a dual fuel engine using methane as the supplementary fuel has been carried out. The paper describes the preliminary work of dual fuel control. Two systems are examined and their behaviour is presented.
Energetically costly behaviours, such as flight, push physiological systems to their limits requiring metabolic rates (MR) that are highly elevated above the resting MR (RMR). Both RMR and MR during...Full Text Available
Health education and awareness involves providing knowledge about causes of illness and choices to promote a change in individual behaviour and, thus, improves survival of individuals. Studies have,...Full Text Available
BackgroundManagement of nightlife in UK cities focuses on creating safe places for individuals to drink. Little is known about intoxication levels as measuring total alcohol consumption...Full Text Available
The consequences of structural modifications at the 5'-OH ribofuranotide moiety of quinoline modified B12 derivatives are discussed in regard of the coordination chemistry, the electrochemical properties and the biological behaviour of the compound. PMID:21850334
A simulation is developed that qualitatively describes the small-zone-gel-filtration behaviour of a reversibly associating protein. The results reflect the dependence of the apparent molecular weight...Full Text Available
In the study three loss-of-feedwater type experiments which were preformed with the PACTEL facility has been calculated with two computer codes. The purpose of the experiments was to gain information about the behaviour of horizontal steam generator in a ...
BackgroundEvent-related potentials (ERPs) may be used as a highly sensitive way of detecting subtle degrees of cognitive dysfunction. On the other hand, impairment of cognitive skills...Full Text Available
BackgroundThe composition of habitual diets is associated with adverse or protective effects on aspects of health. Consequently, UK public health policy strongly advocates dietary...Full Text Available
An introduction to the properties and behaviour of tachyons is presented. The extension of special relativity to include superluminal frames is discussed and the generalized Lorentz transformation is considered. The consequences of the existence of tachyous for general relativity and astrophysics are also summarised. (W.D.L.).
Solid-pseudopapillary tumor (SPT) is a rare neoplasm of the pancreas that usually occurs in young females. It is generally considered a low-grade malignant tumor that can remain asymptomatic for several...Full Text Available
Advanced structural ceramics are presently used in several tribological applications, such as precision instrument bearings, automotive engine parts and cutting tools inserts. Design and selection of advanced ceramics for these applications require reliable data on the effects of temperature, load and environment on the tribological behaviour of these materials. In the present work, the friction and wear behaviour of colloidally processed and pressureless sintered sialon ceramics with phase (#alpha#) have been studied, aiming at increasing #alpha#-sialon in industrial applications as cutting tools. The friction and wear behaviour of sialon ceramics against steel DIN-Ck45K were investigated using a pin-on-disk tribometer under dry sliding conditions at room temperature, in order to eliminate the contribution of lubricant. The experiments were performed with a constant sliding velocity of 0.5 m/s and a contact stress of 2.85 ...
The author resumes what is actually known about the behaviour of war projectiles in the target (wound ballistics). This is function of their nature, their velocity, their air trajectory. The difference between lesions due to slow moving bullets and these due to projectiles with a high kinetic energy is outlined. The last ones create, through the temporary cavitation effect, lesions at distance from the residual visible tract, particularly in the vascular conduits. The therapeutic conclusions, which derive from those ballistic behaviours, are briefly described in matter of repair of vascular war injuries [Acta chir. belg., 1982, 82, 457-461]. PMID:7148288
The thermal degradation and crystallisation behaviours of polyamide12/isotactic polypropylene (PA12/PP) blends were studied. Effects of blend ratio and compatibiliser concentration on the thermal degradation properties of the blends were analysed. The activation energy for degradation in compatibilised and uncompatibilised blends computed using Horowitz-Metzger equation was reported. The blend ratio as well as the presence of compatibiliser has significant effect on the thermal stability of the blends. Phase morphology was found to be one of the decisive factors that affected the thermal stability of both uncompatibilised and compatibilised blends. Melting and crystallisation behaviours of the blends in the presence and absence of compatibiliser were evaluated. It was observed that blendin...
High strain fatigue problem in steam turbine. Cyclic stress strain hysteresis loops and stress relaxation behaviour in 16 h dwell period tests. Variation of stress and strain during tests under nominally strain controlled conditions. Definition of test conditions and of criteria for crack initiation and failure. Comparison of reverse bend and push pull failure data. (orig.) 891 RW/orig. 892 RKD.
The load-carrying capacity and ultimate deformation capacity of timber-concrete composite systems can be significantly influenced by the ductility of the connection between the two materials. The use of more ductile connections can increase the load-carrying capacity of the composite system as well as its ultimate deformation capacity. In this work, the potential increase that might be expected for these two parameters due to the use of ductile connections will be assessed through numerical simulations, taking the non-linear behaviour of the connections into account. Furthermore, the connection ductility required to achieve the maximum load capacity depends on the mechanical properties of the connection as well as on the geometric and mechanical properties of the composite system. There ar...
The DC magnetic susceptibility of the REBa_2F_7 compounds was measured by a SQUID magnetometer in the temperature range 5-300 K. Except for Eu, the other compounds show either Curie law or Curie-Weiss law with relatively small values of paramagnetic Curie temperature, #theta#_p, with effective magnetic moments in the range expected of electronic ground state of the trivalent rare earth ion with appropriate J value. The behaviour of Eu is complex. (orig.).
Long crack fatigue threshold ({delta} K{sub th}) and crack closure behaviour of two thermomechanically processed microalloyed (MA) ferrite-pearlite steels are reported. {delta} K{sub th} and crack closure were measured using a dynamic compliance measurement technique. Crack closure was observed at low load ratios (R < 0.5) and the fatigue thresholds decreased with increasing load ratio. In both steels, the closure-free intrinsic threshold ({delta} K{sub eff} {sub th}) was found to be independent of the load ratio. (orig.)
In this paper we studied the behavior of commercially pure niobium immersed in molten aluminum. The experiments were carried out 800 and 900 deg C during 2 to 128 hours. Chemical and metallographic analyses, as well as microhardness measurements of the niobium specimens were accomplished. An increase of niobium content in the aluminum bath with time was observed. Metallographic observations revealed the formation of Nb Al{sub 3} external intermetallic compound. During dissolution, fragments of this compound settled at the bottom of the crucible. This behaviour was also observed at 900 deg C, nevertheless with higher intensity. (author) 10 refs., 5 figs., 3 tabs.
The post (neutron) -irradiation high-temperature tensile and creep-rupture properties, deformation and fracture characteristics of austenitic alloys, particularly solution annealed Type 316 steel, are surveyed and correlated with the damage structures developed as a function of irradiation temperature (and dose). The mechanisms proposed to explain the irradiation-induced changes in properties and behaviour are summarised. The factors responsible for the observed differences in the post-irradiation and 'in-reactor' creep-rupture properties and behaviour of an austenitic steel are discussed in terms of the helium gas and stress driven growth of small intergranular bubbles and the atom plating associated with their growth and coalescence. (author).
Low cycle fatigue (LCF) of a fourth-generation single-crystal (SC) Ni-base superalloy TMS-138 was studied by comparison with a typical third-generation (TMS-75) and a second-generation (CMSX-4) Ni-base SC superalloys. TMS-138 exhibits improved LCF behaviour under a condition of the R ratio of 0 at temperatures of 1073 K and 1173 K. The addition of refractory elements resulted in a remarkable improvement of the LCF properties compared to those of the reference superalloys due to the different microstructure developed in TMS-138. (orig.)
The decontamination factor is studied as a function of laser fluence for three kinds of clad surfaces viz., plain zircaloy, autoclaved zircaloy and SS with cesium as the test contamination. It has been found that the decontamination factor exhibits a maximal behaviour with the laser fluence and its maximum value occurs at different laser fluences in the three cases. The maximal behaviour is attributed to reduced coupling of energy from the laser beam to the substrate due to the initiation of surface-assisted optical breakdown. The results obtained in the experiment carried out in helium environment qualitatively support this explanation (author)
The importance that must be attached to the phenomenon of stress corrosion cracking of austenitic alloys is emphasized. The relation between chemical composition of various alloys and their sensitivity to cracking is shown with particular reference to the behaviour of Alloy 800. The different effects of alkaline anc chloride environments are discussed. Studies are reported of the general corrosion of Alloy 800 and other alloys in an environment representative of the primary coolant of PWR reactors; and of the behaviour of various alloys (including Alloy 800) in the conditions envisaged for their use for steam generators with superheat up to about 550 deg.C. (U.K.).
In this project the influence of residual compression stresses on the stress corrosion cracking behaviour of the turbine disc steel 26 NiCrMoV 14 5 (Rp(sub 0.2) = 850 N/mm(sup 2)) was investigated. The residual compression stresses were produced by shot p...
This paper presents a supernetwork equilibrium model integrating supply chain networks with a transport network, namely, a supply chain-transport supernetwork equilibrium model. The model takes into account the behaviour of freight carriers and transport network users to endogenously determine the transport costs generated in the supply chain networks. The interaction between transport network and supply chain networks can also be examined. Results of the numerical tests reveal that the improvement of transport network could enhance the efficiency of supply chain networks. The paper makes contributions to modelling of supply chain networks as well as to that of transport networks.
One of the main problems related to optical thin film materials used in high power laser environments is the catastrophic damage caused to them due to laser irradiation. While the influence of ion bombardment on the optical properties of oxide thin films is now a well understood subject, the morphology and crystalline behaviour of these films under ion incidence is not so well studied. Hence, it is of great importance to investigate the effects of ion bombardment during growth on the microstructure and crystalline behaviour of oxide materials.
Although there is service experience of Alloy 800 as tubing for superheaters in conventional and nuclear (HTR) power stations and in PWR heat exchangers, there is no corresponding service experience in sodium-cooled fast reactor steam generators. However, some limited experimental studies have been made of corrosion behaviour, and of possible structure modifications and effects on mechanical properties which occur during exposure of this material to a high temperature sodium environment, and these are summarised in the paper. It is concluded that further work needs to be done before Alloy 800 can be confidently endorsed for use as tubing in fast reactor steam generators. (author).
The interaction of cis-diamminediaquoplatinum(II) nitrate with adenosylcobalamin and a series of alkylcobalamins was studied by carbon-13 nuclear magnetic resonance spectroscopy and by electronic spectroscopy. With these cobalamins cis-(Pt(NH/sub 3/)/sub 2/(OH/sub 2/)/sub 2/)/sup 2 +/ forms adducts in which N(3) of the 5,6-methylbenzimidazole moiety is co-ordinated to platinum(II) rather than to cobalt(III) of the corrin. The chemical shifts of the 5'-methylene carbon of adenosylcobalamin-platinum adduct and of the Co-methyl carbon of the methylcobalamin-platinum adduct are characteristic of these cobalamins in the base-off form. Furthermore, these cobalamin-platinum complexes have visible spectra identical to those of the cobalamins in acidic solution. The /sup 13/C NMR spectrum of the adenosylcobalamin-platinum complex suggests the presence of a second adduct in which platinum(II) complexes are co-ordinated to ...
Porous phosphate heterostructures (PPH), functionalized with different ratios of aminopropyl and mercaptopropyl groups, labelled as Nx=5,25,50-PPH and Sx=5,25,50-PPH, respectively, were tested as adsorbents for Ni(II) and Hg(II) found in industrial sewage from electroplating processes and button battery recycling. X-ray diffraction was used to study the structures. The specific surface area of the pristine material (PPH) was 620m^2g^-^1, whereas the specific surface areas of the modified mercaptopropyl (S5-PPH) and aminopropyl (N5-PPH) were 472 and 223m^2g^-^1, respectively. The adsorption data were fitted to a Langmuir isotherm model. The S5-PPH material was saturated by 120mmol Hg(II) per 100g of material, whereas for Ni(II) adsorption, N25-PPH material displayed the highest adsorption w...
The relationship between serum PG I, PG II levels and extent of atrophic gastritis was examined. The subjects were 64 patients (male: 32, female: 32, 51.9 years old on average) with established diagnosis of either atrophic gastritis or normal. In the X-ray gastric examination, Fuji Computed Radiography (FCR) was used to obtain clear-cut images of the gastric area. Concerning the serum PG I level, patients in the group with atrophic gastritis showed lower levels than those of the people in the group with no atrophic change, but the variation was wide, and no definite tendency was seen in the relationship between the atrophic change and the serum PG I levels. Concerning the serum PG II level, as the atrophic change progresses, the serum PG II level tended to increase gradually. A significant reduction in the PG I/II ratio was seen in the group with atrophic changes (p<0.01) in comparison with the group ...
The relationship between serum PG I, PG II levels and extent of atrophic gastritis was examined. The subjects were 64 patients (male: 32, female: 32, 51.9 years old on average) with established diagnosis of either atrophic gastritis or normal. In the X-ray gastric examination, Fuji Computed Radiography (FCR) was used to obtain clear-cut images of the gastric area. Concerning the serum PG I level, patients in the group with atrophic gastritis showed lower levels than those of the people in the group with no atrophic change, but the variation was wide, and no definite tendency was seen in the relationship between the atrophic change and the serum PG I levels. Concerning the serum PG II level, as the atrophic change progresses, the serum PG II level tended to increase gradually. A significant reduction in the PG I/II ratio was seen in the group with atrophic changes (p<0.01) in comparison with the group ...
The biosorption characteristics of Cd(II) ions using the red alga (Ceramium virgatum) were investigated. Experimental parameters affecting the biosorption process such as pH, contact time, biomass dosage and temperature were studied. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherms. The biosorption capacity of C. virgatum biomass for Cd(II) ions was found to be 39.7 mg/g. From the D-R isotherm model, the mean free energy was calculated as 12.7 kJ/mol, indicating that the biosorption of Cd(II) the metal ions was taken place by chemisorption. The calculated thermodynamic parameters ({delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o}) showed that the biosorption of Cd(II) ions onto C. virgatum was feasible, spontaneous and exothermic at 293-323 K. Evaluation of experimental data in terms of biosorption kinetics showed that the biosorption of ...
Apparent molar volumes V{sub phi} and apparent molar heat capacities C{sub p,phi} were determined for aqueous solutions of nickel(II) nitrate, copper(II) nitrate, and zinc(II) nitrate at molalities m=(0.01 to 0.5) mol {center_dot} kg{sup -1}, and at the pressure p=0.35 MPa. Solution densities obtained using a vibrating-tube densimeter at T=(278.15 to 368.15) K were used to calculate V{sub phi} values. Heat capacity measurements obtained with a twin fixed-cell, differential-output, power-compensating, temperature-scanning calorimeter at T=(278.15 to 393.15) K were used to calculate values of C{sub p,phi}. Our results were then fitted to functions of m and T and compared to literature values.
Parenting programmes are effective interventions for preventing and treating conduct problems in young children. Up to 20% of children in disadvantaged areas have conduct disorder. Recent government initiatives such as targeting early years services to designated disadvantaged Flying Start areas in Wales have resulted in increased nursery-care provision for pre-schoolers, yet little has been done to equip nursery staff with effective child behaviour management strategies. The purpose of this non-randomised trial platform study was to establish the feasibility of delivery and the effectiveness of the new Incredible Years Toddler Parent Programme in supporting nursery staff in managing difficult behaviour in the nursery. The Parent Programme is a 12-session (a two-hour session/week) course for carers/parents of children aged one to three years old, which encourages carers to: establish positive relationships with children through play and ...
The chemical operational concept originally established for the water-steam circuit of Angra II nuclear power plant has undergone several modifications throughout the development of the project. This work discusses the two main modifications giving special attention to the costs involved and analyses the main points and the consequences of such modifications 1 ref., 4 figs., 2 tabs.
System-level-operational testing of the ETX-II test-bed electric vehicle is described and the results discussed. Because the traction battery is a major factor in the performance of an electric vehicle, previously reported work on the sodium-sulfur battery designed for use with the ETX-II is reviewed in detail. Chassis dynamometer performance of the test-bed vehicle met or exceeded design goals and compared reasonably well with SIMPLEV computer modeling results. Areas are identified wherein further work is needed to establish a firmer basis for comparison of the simulation and the observed results.
A lot of effort has been made to spread the application of RTOS in embedded system development in China. RTOS, #mu#C/OS and #mu#C/OS-II, with its opened source code, is well known in embedded systems. Learning RTOS, Using RTOS, becomes more and more popular. The Book of 'Micro C/OS-II The Real-Time Kennel Second Edition' was published in 2002. Here some new progress of the RTOS, especially the safety certifications, the reliability of software is introduced. (authors)
This report describes selective catalytic reduction (SCR) technologies which offer an economical and effective means of reducing nitrogen oxide emissions from electricity generation facilities and reviews the feasibility and cost effectiveness of employing this technology on electricity generating facilities in Ontario. Based on experiences in the United States, in British Columbia, and internationally in Japan and Germany, the indication is that the technology for the installation of SCR systems on new gas-fired combined cycle power plants and existing coal-fired power plants has grown enormously during the past decade, and has been established as the control technology of choice for nitrogen oxide emissions. It is widely acknowledged to reduce power plant nitrogen oxide emissions, and do so at a very reasonable incremental cost. It is estimated that the annualized cost of installing and operating a SCR at a large ...
In the research of a more efficient, less costly, more environmentally responsible and less technically difficult method for generating electrical power from coal, `the Partially Gasified Coal Fired Combined Cycle with a CFBC with Different Speeds (DFBC)` is introduced by Tsinghua University. The high efficiency cycle includes gasification, compressed air heating in a fluidized bed immersed air heater followed by a combustor and the heat recovery of gas turbine exhausted gas used as the combustion of coal in the differential-velocity atmospheric circulating fluidized bed. Superheated steam is raised in the DFBC boiler. A preliminary analysis is made for the choice of combined cycle components. The computer program can be used to evaluate the design and off-design performance of the power plant. The simulation results show that the new system is a valuable coal fired combined cycle system for China, mainly to the improvement of the existing ...
In 1970, the Federal Power Commission predicted a fall from 46% to 27% in 1990 as a result of predicted increases in the use of nuclear power. Today, the Department of Energy expects coal to supply about 50% of electricity generation in 1990. About one-eighth of the world's annual hard coal production is used to make electricity in the United States. Power stations in the country used more coal in 1979 than was produced in the whole Western Europe that year. These 405,000,000 tons of coal equivalent were burned in 1257 individual utilities with an aggregate capacity of 235,000 megawatts. There are coal-fired power plants in 43 of the 50 states. Four factors will be most important in shaping the future development of coal-based electricity: prices, conservation, environmental regulations, and national security. The price differential between coal and oil has now reached a level where it is much more economic for a United States electric utility to build and ...
A life cycle assessment was performed to quantify the non-renewable (fossil) energy use and global warming potential (GWP) in electricity generation from a typical gas fired combined cycle power plant in Singapore. The cost of electricity generation was estimated using a life cycle cost analysis (LCCA) tool. The life cycle assessment (LCA) of a 367.5 MW gas fired combined cycle power plant operating in Singapore revealed that hidden processes consume about 8% additional energy in addition to the fuel embedded energy, and the hidden GWP is about 18%. The natural gas consumed during the operational phase accounted for 82% of the life cycle cost of electricity generation. An empirical relation between plant efficiency and life cycle energy use and GWP in addition to a scenario for electricity cost with varying gas prices and plant efficiency have been established.
A life cycle assessment was performed to quantify the non-renewable (fossil) energy use and global warming potential (GWP) in electricity generation from a typical gas fired combined cycle power plant in Singapore. The cost of electricity generation was estimated using a life cycle cost analysis (LCCA) tool. The life cycle assessment (LCA) of a 367.5 MW gas fired combined cycle power plant operating in Singapore revealed that hidden processes consume about 8% additional energy in addition to the fuel embedded energy, and the hidden GWP is about 18%. The natural gas consumed during the operational phase accounted for 82% of the life cycle cost of electricity generation. An empirical relation between plant efficiency and life cycle energy use and GWP in addition to a scenario for electricity cost with varying gas prices and plant efficiency have been established.
Fully-fired combined cycle plants utilizing the high temperature gas turbine discharge as gas intake for a coal-fired steam generator were developed in the 1960's. Long-term experience and the excellent reliability statistics of the gas turbines of these plants have proven that the thermodynamic, economical and ecological advantages of combined cycle units over conventional units strongly suggest such plants for fossil-fuel applications. This paper describes the design and operation of these plants. Topics are Gersteinwerk Unit K combined-cycle power plant, plant design concept, design criteria and performance, gas turbines, steam generators, steam turbines, various modes of operation, typical plant start-up, environmental considerations, prototype plants and topping old steam turbine plants. It concludes that combined-cycle plants provide efficiencies over 45% with low NO/sub x/ emission and a low emission rate. 15 refs.
The probabilistic external events analysis performed for the Savannah River Site K-reactor PRA considered many different events which are generally perceived to be external'' to the reactor and its systems, such as fires, floods, seismic events, and transportation accidents (as well as many others). Events which have been shown to be significant contributors to risk include seismic events, tornados, a crane failure scenario, fires and dam failures. The total contribution to the core melt frequency from external initiators has been found to be 2.2 {times} 10{sup {minus}4} per year, from which seismic events are the major contributor (1.2 {times} 10{sup {minus}4} per year). Fire initiated events contribute 1.4 {times} 10{sup {minus}7} per year, tornados 5.8 {times} 10{sup {minus}7} per year, dam failures 1.5 {times} 10{sup {minus}6} per year and the crane failure scenario less than 10{sup {minus}4} per year ...
The outlook for natural gas (from both supply and price perspectives) has improved dramatically since the late 1970s, and significant advances have been made in electrical generation technologies which use gas. For example, gas-fired combined-cycle turbine units have become even more efficient and reliable. These units can be installed quickly (12 to 24 months versus 8 to 15 years for coal and nuclear units), and they may be brought on-line in small incremental blocks. This modular construction feature offers greater flexibility to utility planners, and the relatively low capital cost of combined-cycle units reduces financial uncertainties. The purpose of this chapter is to compare two electric power generating options, a new coal-fired powerplant and a new natural gas fired combined-cycle unit, from both economic and environmental perspectives. The comparison is based on a 240 megawatt baseload system.
Deregulation and restructuring changes in the electric power industry have provided opportunities to build new power plants. These power plants, however, will not enjoy long-term power purchase agreements with the utilities they serve, but will have to respond to the market. This is where the term `merchant plant` originates. Calpine Corp. presented its reasons for believing that now is the best time to be building new merchant plants based on modern natural gas-fired, combined-cycle power plants. Among those reasons are: (1) construction of new nuclear power plants has been rejected by people on both sides of the border, (2) attempts to promote alternative energy sources such as solar, wind and biomass have not added significant generation capacity and are not likely to do so in the near future because of their high cost, and (3) coal-fired plants are also facing environmental challenges. For all these reasons, modern natural ...
The increasing price differential between natural gas and coal will create a demand for technology that can allow the displacement of natural gas with coal in power plants. Coal gasification is the standard approach suggested to allow coal to displace natural gas. However, the relatively high capital investment required for coal gasification will require fuel cost differentials higher than those anticipated in the near term before coal gasification replaces natural gas. One way of achieving shorter term displacement of natural gas by coal would be to develop technology that would allow coal to be used as the heat source for the endothermic reforming of natural gas. In a natural gas-fired combined cycle power plant, the endothermic heat of reforming, which would be provided by coal combustion, is recovered in the combined-cycle. Therefore, this portion of the coal`s energy would be converted to electrical power at the high efficiency of the ...
The real thermodynamic inefficiencies in a thermal system are related to exergy destruction and exergy loss. An exergy analysis identifies the system components with the highest exergy destruction and the processes that cause them. However, only a part of the exergy destruction in a component can be avoided. A minimum exergy destruction rate for each system component is imposed by physical, technological, and economic constraints. The difference between the total and the unavoidable exergy destruction rate represents the avoidable exergy destruction rate, which provides a realistic measure of the potential for improving the thermodynamic efficiency of a component. The calculation of avoidable cost rates associated with both exergy destruction and capital investment is described in the paper and is applied to the exergoeconomic evaluation of an externally fired combined cycle power plant. For each plant component, avoidable and unavoidable exergy destructions and ...
For IGCC, the primary investment is too high due to the demand of high gasification efficiency. For PFBCC, the thermal efficiency is too low due to the relatively low turbine inlet temperature and the hot working medium of the gas turbine is not easy to clean. A new scheme is proposed for coal fired combined cycle to overcome the main drawbacks of IGCC and PFBCC. The research targets are developing a new cycle construction of coal fired combined cycle to raise the efficiency and reduce the primary investment. Actually, the new scheme is a synthesis of some existing proposals. It adopts partial gasification to reduce the primary investment of the gasification equipment. The un-gasified surplus solid is then fed to a pressurized fluidized bed boiler, but adopting Curtiss Wright type external combustion to lower the ash content in the working medium. The gas fuel from the partial gasifier is combusted in a top combustor to further increase the ...
The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. Along with the major activity of assembling the components of the 50-lb/hr retort, work was also completed in other areas this quarter. Basic studies of the cracking and coking kinetics of model compounds in a fixed bed reactor were continued. Additionally, as part of the effort to investigate niche market applications for KENTORT II-derived products, a study of the synthesis of carbon fibers from the heavy fraction of KENTORT II shale oil was initiated.
Active Activator (Ac) elements undergo mutations to become nonautonomous Dissociation (Ds) elements at a low frequency. To understand...Full Text Available
... in Taylor and Williamson.* Most satellite sensors cannot be ... The coordinates of the rocket Ii ... I - Incoming Global Radiant Flux between 0.285 and ...
Abstract Copper(II) bis(thiosemicarbazone) are very useful for blood flow and hypoxic imaging. The aim of this study was to identify structure-activity relationships (SARs) within a series of analogues with different substitution patterns in the ligands, in order to design improved hypoxia imaging agents and elucidate hypoxia selectivity mechanisms. Genetic algorithms (GAs) were used to develop specific copper metal-ligand force field parameters for the MM3 force-field calculations. These new parameters produced results in good agreement with experiment and previously reported copper metal-ligand parameters. A successful quantitative SAR (QSAR) for predicting the several classes of Cu(II)-chelating ligands was built using a training set of 21 Cu(II) complexes. The QSAR exhibited a correlat...
missionaries and cannibals puzzle. He noted that in order to be able to use a boat to cross a river one would need ... a quali cation that the vertical exhaust stack ...
... And those who study cognition select problems (eg, tower of Hanoi, missionaries and cannibals, logic theorems) with minimal perceptual and motor ...
Form as the end result of massive star evolution; Type II supernova: collapse of iron core in highly evolved massive star; outer regions blasted away in ...
... centers in materials research. MRSECs address fundamental materials research topics of intellectual ... in materials research. II. PROGRAM DESCRIPTION MRSECs are supported by NSF to undertake materials ...
The biosorption of lead, copper and zinc ions on Rhizopus arrhizus has been studied for three single-component and two binary systems. The equilibrium data have been analysed using the Freundlich adsorption model. The characteristic parameters for the Freundlich adsorption model have been determined and the competition coefficients for the competitive biosorption of Pb(II)-Cu(II) at pH 4.0 and 5.0, and Pb(II)-Zn(II) at pH 5.0 have been calcualted. For the individual single-component isotherms, lead has the highest biosorption capacity followed by copper, then zinc. The capacity of lead in the two binary systems is always significantly greater than those of the other metal ions, in agreement with the single-component data. Only a partial selectivity for copper ions has been obtained at pH 4.0. (orig.)
Hexavalent chromium in corrosion preventive coating 64 ...To prevent corrosion of rims, weights can be provided with a coating. ...integrated clips brought up technical problems due to corrosion
... Science, Computer Vision, Digital Government, Digital Libraries, Digital Society and Technologies ... for Robust Intelligence, Digital Government, and Digital Libraries and Archives. In subsequent years ...
... Ready-to-Eat (MRE) VIII operational ration was evaluated at a field training exercise (Market Square II) with troops of the 82nd Airborne Division. ...
Given a double complex $X$ there are spectral sequences with the $E_2$ terms being either H$_I$ (H$_{II}(X))$ or H$_{II}($H$_I (X))$. But if $H_I(X)=H_{II}(X)=0$ both spectral sequences have all their terms 0. This can happen even though there is nonzero (co)homology of interest associated with $X$. This is frequently the case when dealing with Tate (co)homology. So in this situation the spectral sequences may not give any information about the (co)homology of interest. In this article we give a different way of constructing homology groups of $X$ when H$_I(X)=$H$_{II}(X)=0$. With this result we give a new and elementary proof of balance of Tate homology and cohomology.
This objective of this work was to summarize the main results obtained in previous papers related to the adsorbent-adsorbate interactions involved in the adsorption of naphthalenesulphonic acids and heavy metals (Cd(II) or Hg(II)) by modified activated carbons. The adsorption of organic compounds (1-naphthalenesulphonic acid, 1,5-naphthalenedisulphonic acid and 1,3,6-naphthalenetrisulphonic acid) and inorganic species (Cd(II) and Hg(II)) was studied on a series of ozonized activated carbon in aqueous phase. Commercial activated carbon (Filtrasorb 400) was treated with different ozone doses to study the effect of ozone treatment on its surface properties and investigate the behavior of the treated carbon samples in the above adsorption processes. After ozonation, carbonyl- and carboxyl-type...
A High Performance Power System (HIPPS) is being developed. This system is a coal-fired, combined cycle plant with indirect heating of gas turbine air. Foster Wheeler Development Corporation and a team consisting of Foster Wheeler Energy Corporation, Bechtel Corporation, University of Tennessee Space Institute and Westinghouse Electric Corporation are developing this system. In Phase 1 of the project, a conceptual design of a commercial plant was developed. Technical and economic analyses indicated that the plant would meet the goals of the project which include a 47 percent efficiency (HHV) and a 10 percent lower cost of electricity than an equivalent size PC plant. The concept uses a pyrolyzation process to convert coal into fuel gas and char. The char is fired in a High Temperature Advanced Furnace (HITAF). The HITAF is a pulverized fuel-fired boiler/air heater where steam is generated and gas turbine air is indirectly ...
The coal-fired combined cycle with partial gasification and fluidized bed combustion (PGFBC-CC), also referred to as a hybrid cycle, has advantages of staged energy conversion and utilization, which can attain high thermal efficiency with low emissions. Four kinds of PGFBC-CC are studied in this paper, two based on pressurized fluidized bed combustion (PFBC) and two on atmospheric fluidized bed combustion (AFBC). Thermal performance calculations and parametric analyses were performed. On the basis of the results, from the above analyses, the best integration system for China is suggested. In addition, a preliminary exergetic analysis is carried out for three of the PGFBC-CC variants.
The first 750 MW block of the new South Humber Bank gas-fired combined cycle power plant, sited about 300 km north from London, was officially commissioned in September 12th 1997. The project has been a major success story for Imatran Voima Oy (IVO), which developed the concept and managed the project and owns 22.5 % of the plant; and ABB Power Plants Limited, responsible for the turnkey delivery. IVO Generation Services (UK) is responsible for the running and maintenance of the facility. IVO also manages two other existing plants in Britain, at Brigg (240 MW) and Peterborough (360 MW)
The first 750 MW block of the new South Humber Bank gas-fired combined cycle power plant, sited about 300 km north from London, was officially commissioned in September 12th 1997. The project has been a major success story for Imatran Voima Oy (IVO), which developed the concept and managed the project and owns 22.5 % of the plant; and ABB Power Plants Limited, responsible for the turnkey delivery. IVO Generation Services (UK) is responsible for the running and maintenance of the facility. IVO also manages two other existing plants in Britain, at Brigg (240 MW) and Peterborough (360 MW).
Concepts involving combined gas-turbine/steam-turbine power-generation plants, in which the fuel gas for the gas turbine is produced via the gasification of coal, are now extremely advanced. This technology already permits efficiencies of around 50% current development targets view 65% as achievable. In conventional technology, efficiencies are tied to conditions, such as air and cooling-water temperatures, at the particular location. In combined-cycle power plants, the properties of the fuel coal also play an important part. There are, in face, coals which can be more advantageously used in a combined-cycle power plant than in a conventional one. These differences, combined with advantageous concepts for coal-fired combined-cycle power-generating plants, are presented and analyzed. Particular attention is devoted to individual losses occurring at coal conversion, thermodynamic cycles, integration of processes and internal consumptions. 14 refs., 14 figs., 4 tabs.
The fossil fuel consumption and pollutant emissions in a coal fired fluidized bed boiler could be reduced by biomass pyrolysis gas reburning. The influence of three kinds of biomass pyrolysis gases on the emission of N2O in a laboratory scale fluidized bed was investigated using the mechanism of GRI3.0 in this paper. The results showed that: the effect of sawdust pyrolysis gas reburning on N2O was more significant than that of rice husk and orange peel under the same conditions; the increase of initial oxygen content from 1% to 8% in flue gas would restrain the decomposition of N2O; the N2O decomposition was enhanced by increasing reaction temperature from 1073.15 K to 1323.15 K, and the decomposition rate may reach 99% at 1223.15 K.
Integrative and firing properties are important characteristics of neuronal circuits and these responses are determined in large part by the repertoire of ion channels they express, which can vary considerably between cell types. Recently, a new mode of operation of voltage dependent sodium channels has been described that generates a so-called resurgent Na^+ current. Accumulating evidence suggests resurgent Na current participates in the generation of sub-threshold inward Na^+ current causing membrane depolarization which provides the necessary drive to fire high-frequency action potentials. Recent studies indicate that resurgent Na^+ current could be a more widespread feature than previously thought.
The results of a study assessing natural-gas-fired combined-cycle (GFCC) power generation in the electric-utility sector are presented. This study quantified the economic benefits attributable to GFCC generation and examined the characteristics of GFCC technology that produce these benefits and the ways that these benefits vary among regions in the country. The impacts of changes in important economic parameters (capital cost, fuel price, etc.) as well as the impact of advances in GFCC technology were considered. Use of GFCC technology in the electric-utility sector could play an important role in a least-cost planning strategy and thereby provide significant benefits to the utilities and their customers. Potential benefits include reduced capital and operating costs, more effective matching of load growth and capacity additions, and greater system reliability. 8 refs., 3 tabs.
Adding capacity to coal-fired plants in small increments of an overall integrated program may be the solution to the 10-year lead time required for the construction of a new plant. A preliminary study evaluates the technical and economic feasibility of a modular natural gas and coal-fired combined-cycle power plant which can be installed in three distinct phases. The plant sizes are suitable for large industrial and utility applications. The Modular Block Power Plant (MBPP) concept offers the advantages of phase construction, lower capital cost, lower cost electricity, lower air emissions, lower water requirements, and reduced solid waste discharge. Other advantages include part load availability, reduced coal inventory requirements, and easier plant siting. 11 figures, 4 tables.
A survey was undertaken of literature on the conversion of coke-fired cupola furnaces so that they can be fuelled, either wholly or partially, with natural gas. The aim was to determine the most suitable method for a specific furnace. Substitution with natural gas can result in speedier adjustment and control of the smelting process and in addition operational costs are reduced as natural gas is a cheaper fuel. The payback period would be one year. Pollutive emissions would be reduced. It was concluded that the most satisfactory solution would be that 3-4 gas burners should be placed immediately above the smelting zone in the furnace. Each burner should be placed in a separate combustion box in which the complete combustion process could take place. The burners should be placed symmetrically about the furnace, pointing at a small degree downwards. In this way the combustion chamber will not be filled with materials from the furnace and the burners will not be ...
Developing models for the electrical behavior of exploding bridgewire circuits requires high-quality data of a type not usually generated in routine tests of detonator hardware. To obtain a precise measurement of the time of bridgewire burst relative to current start, one must simultaneously record the current, i, and either di/dt or the voltage across the bridgewire. To fully develop and test a model it is also necessary to vary the bridgewire cross sections and geometry, firing circuit characteristics and charging voltage for the firing circuits over as wide a range as possible. As a part of developing an electrical model for aluminum and copper bridgewires, we have conducted parameter studies on some flat copper and aluminum bridgewires. Most of the work was done on aluminum bridgewires, with a few experiments on copper. We will report the experimental results from these studies and compare them with model predictions.
The use of selective additives such as MgO as a sintering aid and a rare earth oxide as a grain growth inhibitor, has allowed the manufacture of beryllia ceramics having close to theoretical density. The grain size and grain size distribution can be controlled by an optimum firing schedule leaving a remnant porosity which is extremely fine (0.2 {mu}m). This structure is compared with conventional BeO ceramics, densified by liquid phase sintering, which develops a glassy grain boundary and retains large pores up to 3 {mu}m. The significantly improved strength properties, extremely fine pores,the 'pinning effect' of rare earth oxide, and the superior surface finish both in the as-fired and polished state are discussed in relation to the micro-structure. (orig.).
This research report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the feasibility of setting up 'MINERGIE' low-energy-consumption module standards for the production of heat in small residential buildings. The aims of the standards and the basic idea behind the MINERGIE-modules are discussed. The concepts of the modules for heat pumps and wood-fired heating systems and their combination with solar installations are examined, as are their areas of application. The requirements placed on the modules are listed. System concepts, including simple schematics for typical installations, are presented for wood-log, wood-chippings and pellets-fired systems as well as for ground-loop and air-water heat pump systems as well as their solar-aided counterparts. The results of cost-benefit analyses are presented and questions regarding system guarantee and liability are examined.
This paper presents a study involving prediction of a complicated maneuvering target, with the aim of improving the tracking performance of a fire control system (FCS). In this study, we predict the position of a complicated maneuvering target 5 s in advance using the information up to the current time. Because of the large error caused by the complicated maneuvers and the long prediction time interval, the mechanical system of the fire control system will take a heavy load. In order to cope with this problem, several approaches to decreasing the prediction error have been proposed including the prediction algorithms based on the multiple model(MM) filter, interacting multiple model (IMM) filter, and variable dimension with input estimation (VDIE) filter. Finally, comparative simulation re...
We investigated the impacts of forest thinning, prescribed fire, and contour ripping on community level physiological profiles (CLPP) of the soil microbial population in postmining forest rehabilitation. We hypothesized that these management practices would affect CLPP via an influence on the quality and quantity of soil organic matter. The study site was an area of Jarrah (Eucalyptus marginata Donn ex Sm.) forest rehabilitation that had been mined for bauxite 12?years previously. Three replicate plots (20???20?m) were established in nontreated forest and in forest thinned from 3,000?8,000 stems ha?1 to 600?800 stems ha?1 in April (autumn) of 2003, followed either by a prescribed fire in September (spring) of 2003 or left nonburned. Soil samples were collected in August 2004 from two soil ...
Rapid technology improvements, resulting in high efficiency, emissions reduction and low generation cost, are making gas turbines the generation technology of choice despite some recent reliability problems. The basic reason for the dominance is high efficiency. The rapid pace of gas-turbine technology improvement in the 1990s drove combined-cycle thermal efficiency to nearly 60 percent with natural gas as the fuel. It will probably go even higher after the year 2000. In addition, the gas-fired combined cycle is a bargain. With natural gas prices where they are right now, it is the least-cost generation operation for power producers with access to gas. Many will replace older, high-cost power plants with new gas-fired combined cycle power plants.
The report reviews the activity during the fourth year of Gas Research Institute's Gas Appliance Technology Center program. Work on gas appliances involved a conceptual table-top multi-function oven, development of an indirect-fired conveyor oven, and performance comparisons of smooth cooktops. Performance-evaluation methods for commercial ovens were evaluated. Design improvements were made to a direct-fired conveyor oven and a pulse-combustion deep-fat fryer. Performance of common vents were studied, and a device was designed to allow incorporation of appliances with positive vent pressures into such systems. Standards-related work included draft-hood capacities, flexible corrugated-connector corrosion, and sediment trap efficiencies. Heating-related work comprised conceptual design of a vented baseboard heater and a centralized heat-transfer fluid system.
This document contains a summarization of the results and insights from the Level 1 accident sequence analyses of internally initiated events, internally initiated fire and flood events, seismically initiated events, and the Level 2/3 risk analysis of internally initiated events (excluding fire and flood) for Surry, Unit 1. The analysis was confined to mid-loop operation, which can occur during three plant operational states (identified as POSs R6 and R10 during a refueling outage, and POS D6 during drained maintenance). The report summarizes the Level 1 information contained in Volumes 2--5 and the Level 2/3 information contained in Volume 6 of NUREG/CR-6144.
The paper discusses a number of recent studies investigating into the energy conservation and environmental impacts of electric heating systems (off-peak storage systems). In future, i.e. in and after 1993, off-peak storage systems will be evaluated through comparative analyses of oil-fired heating systems, pollutant emission analyses, the eventual success of pollution abatement measures designed for power plant emissions to keep within the legal limiting values, and the possible abandonment of pollution abatement measures abroad. Opposing the electric heating studies submitted by the electric power industry the author refutes their favourable results referring to the palliative selection of inadequate or vague parameters. Assuming average power plant pollutant emissions of 180 mg/standard/sup 3/ the nitrogen oxide emissions of oil-fired heating systems (134.1 kg/Tj) are found to be below those of off-peak storage systems (242.5 kg/Tj).
The optimization of the safety characteristics of electrical installations in industrial plants with explosion or fire hazards can be obtained only through a careful interdisciplinary study and analysis carried out at the onset of the plant project design phase. The least complex and costly and safest solutions are those which are born from plant designs which take into account the typology of the industrial process or technology, or which incorporate pollution abatement measures and adequate safety measures for the electrical installations. This paper provides examples to illustrate how the global plant economy is fundamentally dependant upon a multi-disciplinary initial effort in design analyses. Comments are made relevant to the adequacy of the safety requirements established by existing and planned Italian norms in dealing with safety and fire protection for high-tech industrial plant electrical installations.
A large number of proven technical solutions exists for the use of renewable energies. However, their dissemination is still too slow to meet the political goal of substituting for 8-15% of the primary energy demand in the European Union by the year 2010. Even renewable energy systems (RES) with an economic potential are only partly exploited. The FIRE research project financed partly in the JOULE program analyses and compares the means of financing RES in Austria, Denmark, Germany, the Netherlands, Spain, Sweden and the United Kingdom to put forward best practice recommendations so that renewable energy depolyments will occur at a faster rate. FIRE addresses to politicians, to potential investors and to project-developers. (orig./RHM)
Trace elements were extracted from a coal-fired power plant electrostatic precipitator ash with nitric acid, hydrochloric acid, citric acid, redistilled water, and ammonium hydroxide as extractants. Effluent waters at this plant were sampled to assess the elevation of trace element concentrations compared with intake waters. The results showed a positive correlation between those elements most extractable by water (B, F, Mo, and Se) or acid (As, B, Cd, F, Mo, and Se) and those elements most elevated in effluent waters (As, B, F, Mo, and Se).
Fires in the operating room continue to present a hazard to patients, at times with catastrophic and debilitating results. Recent data from closed claim files reveal oxygen, electrosurgical unit (ESU), and surgical drapes are common components of the fire triangle in the operating room. In this era of biotechnological sophistication, why are surgical drapes flammable? The purpose of this study was to test the flammability of different surgical drape materials and to determine the time to ignition using a bipolar ESU device in 21%, 35%, and 100% oxygen concentrations. Results show that regardless of oxygen concentration surgical drapes, when exposed to close contact with the ESU, are flammable. Time to ignition decreases with increasing concentrations of oxygen as expected. One of the surgical drapes tested was advertised to the hospital as nonflammable. Future research should focus on surgical drape materials and aim to reduce the flammability ...
This study concerns the thermotolerance of spores of mesophilic fungi isolated from a tropical semi-arid habitat subject to dry season fire in the Western Ghats, southern India. Among 25 species of Ascomycota isolated from leaf litter, nine were able to grow after incubation in a drying oven for 2h at 100degreeC; the spores of two of these species survived 2h incubation at 110degreeC, and one survived exposure to 115degreeC for 2h. The range of thermotolerance among mesophilic fungi isolated from the leaf litter was surprising: filamentous fungi from other habitats, including species that colonize scorched vegetation after fires and thermophilic forms occurring in self-heating plant composts, cannot survive even brief exposure to such high temperatures. It is possible that the exceptional ...
This paper provides both a detailed history of environmental change in the Sierra Nevada over the past 1,800?years and evidence for climate teleconnections between the Sierra Nevada and Greenland during the late Holocene. A review of Greenland ice core data suggests that the magnitudes of abrupt changes in temperature and precipitation increased beginning c. 3,700 and 3,000?years ago, respectively. Precipitation increased abruptly 1,300?years ago. Comparing paleotemperature data from Cirque Peak, CA with paleoprecipitation data from Pyramid Lake, NV suggests that hot temperatures occurred at the beginnings of most severe droughts in the Sierra Nevada over the past 1,800?years. Severe fires and erosion also occurred at Coburn Lake, CA at the beginning of all severe droughts in the Sierra Ne...
In order to study the intragenic profiles of active transcription, we determined the relative levels of active RNA polymerase II present at the 3′- and 5′-ends of 261 yeast genes by...Full Text Available
Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake studies show increases in ...
Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake studies show increases in ...
The theoretical evolution of a horizontal branch star of Population II is followed through the helium burning in the core phase and is compared with the results given by other investigators. The m- fluence of different physics and interpolation schemes in the opacity tables is discussed. Some thoughts are given on the explanation of the erratic period variations observed in some of the RR Lyrae variables in the globular clusters. (auth)