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Fire theories

Further, the fusain samples we examined contained methyl groups (in amounts comparable to those in higher rank coals). The presence of such group in fusains would itself rule out the forest fire theory or any other concept which envisages exposure to high temperatures (600°C.) in forming fusains. [Pg.361]

Somasundaran P 1978 Theories of grinding Ceramic Processing Before Firing ed G Y Onoda Jr and L Hench (New York Wiiey) pp 105-23... [Pg.2774]

Stahl subsequently renamed the terra pingnis phlogiston, the motion of fire (or heat), the essential element of all combnstible materials. Thns the phlogiston theory was born to explain all combnstion and was widely accepted for most of the eighteenth centnry by, among others, such luminaries of chemistry as Joseph Priestley. [Pg.27]

The concept that all substances are composed of elements and atoms goes back at least 2000 years. Originally, only four elements were recognized air, earth, fire, and water. Each substance was thought to consist of very small particles, called atoms, that could not be subdivided any further. This early mental concept of the nature of matter was extremely prescient, considering there were no experimental results to indicate that matter should be so and none to verify that it was so. Modern atomic theory is much more rigorously based, and we even have the ability to see atoms with special tunneling microscopes. All of chemistry is based on how atoms react with each other. [Pg.335]

Coating Theory. This theory includes fire retardants which form an impervious skin on the fiber surface. This coating may be formed during normal chemical finishing, or subsequently when the fire retardant and substrate are heated. It excludes the air necessary for flame propagation and traps any tarry volatiles produced during pyrolysis of the substrate. Examples of this type of agent include the easily fusible salts such as carbonates or borates. [Pg.485]

Dehydration or Chemical Theory. In the dehydration or chemical theory, catalytic dehydration of ceUulose occurs. The decomposition path of ceUulose is altered so that flammable tars and gases are reduced and the amount of char is increased ie, upon combustion, ceUulose produces mainly carbon and water, rather than carbon dioxide and water. Because of catalytic dehydration, most fire-resistant cottons decompose at lower temperatures than do untreated cottons, eg, flame-resistant cottons decompose at 275—325°C compared with about 375°C for untreated cotton. Phosphoric acid and sulfuric acid [8014-95-7] are good examples of dehydrating agents that can act as efficient flame retardants (15—17). [Pg.485]

In theory, whole-tree-energy plants have the potential to be more efficient than existing wood-fired generators, which are fueled by chipped wood with a relatively high moisture content (45%). The dried whole trees have a moisture content below 25%, and whole-tree plants potentially can be built to have a greater capacity and to employ high pressure, high temperature steam. [Pg.108]

Once a fire has started, control of the fire can be accomplished in several ways through water systems (by reducing the temperature), carbon dioxide or foam systems (by limiting oxygen), or through removal of the substrate (by shutting off valves or other controls). Chapter 4 provides detailed discussion on the theories of fire and specific information on hydrocarbons, as well as chemical specific fire characteristics. [Pg.173]

Draw the fire triangle and explain the simple theory of combustion. [Pg.187]

Scale-model experiments have been used to study a variety of ventilation problems as air movement in a room, air movement around a building, energy flow in a building, contaminant distribution at an operator s workplace, and smoke movement in a building on fire. The theory is discussed at a general level in the references. [Pg.1176]

Reid, R. C. 1980. Some theories on boiling liquid expanding vapor explosions. Fire. March 1980 525-526. [Pg.245]

This book is divided into five parts the problem, accidents, health risk, hazard risk, and hazard risk analysis. Part 1, an introduction to HS AM, presents legal considerations, emergency planning, and emergency response. This Part basically ser es as an oveiwiew to the more teclmical topics covered in the remainder of the book. Part 11 treats the broad subject of accidents, discussing fires, explosions and other accidents. The chapters in Parts 111 and Part IV provide introductory material to health and hazard risk assessment, respectively. Pai1 V examines hazaid risk analysis in significant detail. The thiee chapters in this final part include material on fundamentals of applicable statistics theory, and the applications and calculations of risk analysis for real systems. [Pg.661]

Report 97 Rubber Compounding Ingredients - Need, Theory and Innovation, Part II Processing, Bonding, Fire Retardants, C. Hepburn, University of Ulster. [Pg.132]

In this chapter, AFM palpation was introduced to verify the entropic elasticity of a single polymer chain and affine deformation hypothesis, both of which are the fundamental subject of mbber physics. The method was also applied to CB-reinforced NR which is one of the most important product from the industrial viewpoint. The current status of arts for the method is still unsophisticated. It would be rather said that we are now in the same stage as the ancients who acquired fire. However, we believe that here is the clue for the conversion of rubber science from theory-guided science into experiment-guided science. AFM is not merely high-resolution microscopy, but a doctor in the twenty-first century who can palpate materials at nanometer scale. [Pg.603]

C. Hepburn, Rubber compounding ingredients—need, theory and innovation Part II—Processing, bonding, fire retardants. Report 97, Rapra, 1997. [Pg.1040]

Combustion has a very long history. From antiquity up to the middle ages, fire along with earth, water, and air was considered to be one of the four basic elements in the universe. However, with the work of Antoine Lavoisier, one of the initiators of the Chemical Revolution and discoverer of the Law of Conservation of Mass (1785), its importance was reduced. In 1775-1777, Lavoisier was the first to postulate that the key to combustion was oxygen. He realized that the newly isolated constituent of air (Joseph Priestley in England and Carl Scheele in Sweden, 1772-1774) was an element he then named it and formulated a new definition of combustion, as the process of chemical reactions with oxygen. In precise, quantitative experiments he laid the foundations for the new theory, which gained wide acceptance over a relatively short period. [Pg.1]


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See also in sourсe #XX -- [ Pg.188 ]




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