Foreign materials

The visible crystals that develop during a crystallization procedure are built up as a result of growth either on nuclei of the material itself or surfaces of foreign material serving the same purpose. Neglecting for the moment the matter of impurities, nucleation theory provides an explanation for certain qualitative observations in the case of solutions. 

Defects (total) include damaged kernels (total), foreign material, and shmnken and broken kernels. The sum of these three factors may not exceed the limit for defects. 

The propellant is dry-screened to remove dust and foreign material, and excess graphite. Unacceptable propellant from the dry-screen operation may be returned to the graining stage for reworking. The product is blended in large rotating barrels for baUistic uniformity. 

H. Schmit2, Stahl- isen-l istenjSteel-Iron Joists, 7th ed., Verein Deutsche Eisenhuttenleute (VDEh), Dusseldorf, Germany, 1987. 2500 German and 1000 foreign materials covered, also ia a computerized database. 

Fine-grained deposits are usually obtained from complex ion solutions, eg, cyanide, or using certain addition agents. These deposits are less pure, less dense, and exhibit higher electrical resistivities because of the presence of foreign material. 

TFM = total foreign materials or total of all substances that are not insoluble lead compounds. 

In the wet method, as practiced in Colombia, freshly picked ripe coffee cherries are fed into a tank for initial washing. Stones and other foreign material are removed. The cherries are then transferred to depulping machines which remove the outer skin and most of the pulp. However, some pulp mucilage clings to the parchment shells that encase the coffee beans. Fermentation tanks, usually containing water, remove the last portions of the pulp. Fermentation may last from twelve hours to several days. Because prolonged fermentation may cause development of undesirable flavors and odors in the beans, some operators use enzymes to accelerate the process. 

A skin wound cleanser is a nonirritating, Hquid preparation (or product to be used with water) that assists in the removal of foreign material from small superficial wounds, does not delay wound healing, and may contain an antimicrobial ingredient. 

Dirty. The shell is unbroken and has adhering dirt or foreign materials, prominent stains, or moderate stains covering more than one-fourth of the shell surface. 

Remove detritus, trash, or accumulations of foreign material on a regular basis. 

Deposits stimulate tubercle formation. Hence, regions where foreign material accumulates are common tubercle breeding grounds. Stagnant, low-flow areas also promote tubercle growth. 

The use of dispersants is highly recommended in systems containing silt, sand, oil, grease, biological material, and/or other foreign material. Not only does increased dispersion generally increase the effectiveness of chemical inhibition, it also prevents nucleation of oxygen concentration cells beneath foulants. 

Contaminants/ Inspect drum before filling foreign material in drum, leading to reaction in drum. CCPS G-3 CCPS G-15 CCPS G-29 CCPS G-30... 

Antibodies secreted by B cells bind to foreign material (antigen) and serve as tags or identifiers for such material. Antibody-tagged bacteria. 

To be able to check guaranteed performance without the fouling effects caused by foreign material or impurities in actual duty gas. 

Factors affecting laboratory polymerisation of the monomer have been discussed" and these indicate that a Ziegler-Natta catalyst system of violet TiCl3 and diethyl aluminium chloride should be used to react the monomer in a hydrocarbon diluent at atmospheric pressure and at 30-60°C. One of the aims is to get a relatively coarse slurry from which may be washed foreign material such as catalyst residues, using for example methyl alcohol. For commercial materials these washed polymers are then dried and compounded with an antioxidant and if required other additives such as pigments. 

Prevent suek-baek of foreign material into the eylinder by use of eheek valves or vaeuum break traps. 

Health Hazards Information - Recommended Personal Protective Equipment Eye protection Symptoms Following Eiqzosure Dust irritates eyes in same way as any foreign material. Penetration of skin by fragments of metal is likely to produce local irritation, blisters, and ulcers which may become infected General Treatment for Exposure EYES flush with water to remove dust. SKIN treat as any puncture Toxicity by Inhalation (Threshold Limit Value) Data not available Short-Term Inhalation Limits Not pertinent Toxicity by Ingestion Oral LDLo (lowest lethal dose) = 230 mg/kg (dog) Late Toxicity Data not available Vtqtor (Gas) Irritant Characteristics Not pertinent Liquid or Solid Irritant Characteristics Data not available Odor Threshold Not pertinent. 

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