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The ignition, puffing and sooting characteristics of Chinese RP-3 kerosene droplet burning have been studied using high-speed, OH* chemiluminescence and soot thermal radiation imaging. The experiments were conducted in air at standard temperature and sub-atmospheric pressures ranging from 0.2 bar to 1 bar. The kerosene droplet was supported by a thermocouple tip and ignited by a retractable coiled heating wire. The results showed that the ignition delay time increased with a decrease of the ambient pressure, due to an increased distance between kerosene and oxygen molecules. Steady burning and disruptive burning were identified following the ignition. OH* chemiluminescence images showed a spherical flame and a longer flame standoff distance under a lower pressure. The puffing intensity was observed to be enhanced with a reduction of the ambient pressure, and a decreased pressure was found to lower the sooting emission.

The book begins with a historical overview of chromatography in general and significant developments in the various fields of chromatography. The question of why we use chromatography is discussed. The second section deals with the fundamentals of separation science and introduces phase separation and this is discussed in terms of both plate theory and rate theory. The van Deemter equation is introduced and each term discussed with particular reference to practical aspects of optimising average linear velocity of the carrier gas. Feed volumes, symmetry, resolution and column overloading are all introduced. The final section covers the units used as well as Boyles, Charles, Dalton and Avogadro's laws leading up to the ideal gas law. The importance of normalising gas analysis results to standard temperature and pressure is discussed.

The adoption of wheat straw as a fuel for gasification processes has been hindered due to a lack of experience and its propensity to cause bed agglomeration in fluidised bed gasifiers. In this study wheat straw was gasified in a small scale, air blown bubbling fluidised bed using mullite as bed material. The gasifier was successfully operated and isothermal bed conditions maintained at temperatures up to 750 ◦C. Below this temperature, the gasifier was operated at equivalence ratios from 0.1 to 0.26. The maximum lower heating value of the producer gas was approximately 3.6 MJm−3 at standard temperature and pressure (STP) conditions and was obtained at an equivalence ratio of 0.165. In general, a producer gas with a lower heating value of approximately 3 MJm−3 at STP could be obtained across the entire range of equivalence ratios operated. The lower heating value tended to fluctuate, however, and it was considered more appropriate for use in heat applications than as a fuel for internal combustion engines. The concentration of combustibles in the producer gas was lower than that obtained from the gasification of wheat straw in a dual distributor type gasifier and a circulating fluidised bed. These differences were associated with reactor design and, in the case of the circulating fluidised bed, with higher temperatures. Equilibrium modelling at adiabatic conditions, which provides the maximum performance of the system, showed that the gasifier was operating at suboptimal equivalence ratios to achieve greatest efficiencies. The maximum calculated theoretical cold gas efficiency of 73% was obtained at an equivalence ratio of 0.35. Science Foundation Ireland Charles Parsons Energy Research Award Department of Communications, Energy and Natural Resources of the Government of Ireland

This chapter investigates the physical properties of polymers using thermal analysis techniques. The effect of the presence of a solvent during the cure of a thermoharding system is discussed. The physical properties of cured resin systems are tested using rectangular casting samples and/or film samples on a metal background. The casting test samples are obtained after the cure of a proper resin/curing agent mixture without any solvent present. To make a film test sample, however, a solvent has to be added nearly always. The physical properties, such as the Tg-value, of such film samples after cure often seem to be lower than those of the solvent-free prepared casting samples. The three samples are then cured using the more or less standard temperature treatments. DSC measurements are subsequently used to measure the Tg-values of these systems.

Publisher Summary This chapter presents service time-voltage data, service life-ohmic load curves, and effects of operating temperature on service life of primary batteries. The primary battery discussed are silver-zinc cells, alkaline manganese dioxide cells, carbon-zinc cells, mercury-zinc cells, lithium types, manganese dioxide-magnesium perchlorate primary batteries, and thermally activated batteries. In service time-voltage data voltage versus hours of service curves can be prepared at different temperatures to show the effect of cell temperature on hours of service obtainable. Another way of expressing the performance of batteries is plots showing the effect of ohmic load on the battery versus hours of service obtained to a particular end-point voltage when the battery is at a particular standard temperature. This type of curve shows the influence of ohmic load on hours of service obtained for 1.5 V alkaline manganese cells at 20°C to an end-point voltage of 0.8 V/cell. Such curves are prepared for a series of battery temperatures to show the effect of temperature on service life at a particular ohmic load. A very effective way of showing the effect of battery temperature on service life is to plot temperature versus the battery capacity obtained to the end-point voltage at that temperature expressed as a percentage of the battery capacity obtained at a standard battery temperature, usually 20 or 21 °C.

This chapter discusses the basic properties of air and gases. The chapter is widened further to include brief description of the properties of airborne contaminant gases and vapors as a basis for recognizing the similarities and differences between aerosol and gaseous contaminants. Air is a mixture of gases, the main constituents being nitrogen and oxygen, with a variety of other trace gases including argon, carbon dioxide, and water vapor. It is a colourless, odorless gas of density 1.29 kg m -3 at a standard temperature and pressure (STP) of 20°C (293°K) and pressure of 1.01 x 10 5 undergo perfect collisions with one another in which no energy is lost.

The properties of elastic fluids (i.e. gases) depend especially on the facts that: (1) they possess weight; (2) they expand in all directions unless restrained; and (3) they allow themselves to be more and more compressed as the force of compression increases. These properties can be explained if we assume a fluid to consist of a very large number of small particles in rapid motion. If such a fluid is placed in a cylindrical container with a movable piston on which there rests a weight P9 then the particles will strike against the piston and hold it up by their impacts; the fluid will expand as the weight P is moved or reduced, and will become denser if the weight is increased. We can find the relation between P and the density of the fluid by computing the effect of changing the volume underneath the piston. If the volume is decreased, the fluid will exert a greater force on the piston, first, because the number of particles is now greater in proportion to the smaller space in which they are confined, and secondly because any given particle makes more frequent impacts. If in addition we assume that the particles themselves are of negligible size, then it follows that the force of compression is approximately inversely proportional to the volume occupied by the air, if the temperature is fixed; and, if the temperature changes, the force of compression will also change, so that it will be proportional to the square of the velocity of the particles. This result enables us to measure the temperature of a gas by the pressure it exerts; the standard temperature from which the rest are measured should be obtained from boiling rainwater, because this no doubt has very nearly the same temperature all over the earth. Experiments to measure temperature and pressure are described. The theory is applied to atmospheric phenomena and to the firing of projectiles from cannons.