Physical tests spread

These tests along with experience from fatal fires demonstrate that it is absolutely essential to restrict the speed of fire along internal surfaces. The degree to which flame spreads across the surface of a lining material is classified by a physical test which is detailed in British Standard BS 476 Part 1. 

Fire retardancy of wood involves a complex series of simultaneous chemical reactions, the products of which take part in subsequent reactions. Most FRs used for wood increase the dehydration reactions that occur during thermal degradation so that more char and fewer combustible volatiles are produced. The mechanism by which this happens depends on the particular FR and the thermal-physical environment. The effectiveness of a FR treatment depends upon the performance rating of the treated material when tested in accordance with ASTM E84 (no greater flame spread than 25). 

Principally different physical laws govern the heat transfer by convection, conduction and radiation. No wonder that often the flame spread rate results obtained in small-, medium- or large -scale material tests do not correlate well. 

Testing techniques for the evaluation of physical properties and other properties of finished margarine products as well as low-fat spreads have been stated to include (4, 91) appearance, oral melting characteristics, oil exudation, slump (collapse), penetrations, spreadability, emulsion viscosity at 35°C (95°F), emulsion drop size, and electrical conductivity. 

The primary tumor is assessed with chest x-rays and fiberoptic bronchoscopy, whereas lymphatic spread is usually assessed by mediastinoscopy, gallium-67 citrate scanning, and CT and/or PET scans. If the history and physical examination or other routine clinical studies (e.g., complete blood cell count and liver function tests) suggest the possibility of metastatic disease, then special scans (e.g., bone, brain, or liver) or biopsies (e.g., bone marrow or liver) may be necessary for... 

Laboratory testing shows that visual examination and viscosity measurements are not sufficient to fully define polymer solvation. In this work, the solvation of hydroxyethyl cellulose (HEC) and xanthan has been studied. These polymers are both widely used in various petroleum applications. HEC is used in many workover and completion applications, while xanthan has its most wide spread uses in drilling and enhanced oil recovery (EOR) applications. Solublization of both polymers results in fluids with pseudoplastic (or shear thinning properties). Even though the polymers both exhibit pseudoplastic behivior, the polymers vary considerably as to their molecular size and physical properties. 

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