Impact danger

Dry nitrocellulose, which bums rapidly and furiously, may detonate if present in large quantities or if confined. Nitrocellulose is a dangerous material to handle in the dry state because of sensitivity to friction, static electricity, impact, and heat. Nitrocellulose is always shipped wet with water or alcohol. The higher the nitrogen content the more sensitive it tends to be. Even nitrocellulose having 40% water detonates if confined and sufftcientiy activated. AH large-scale processes use nitric—sulfuric acid mixtures for nitration (127—132). 

THPOH—Ammonia—Tris Finish. By far the most effective finish for polyester—cotton textiles was a system based on the THPOH—NH treatment of the cotton component either foUowed or preceded by the appUcation of Tris finish to the polyester component. This combined treatment appeared to be effective on almost any polyester—cotton blend. A large amount of fabric treated in this way was sold throughout the United States and much of the rest of the world. Shortly after the introduction of Tris finishing, Tris was found to be a carcinogen. Most of the Tris treated production was in children s sleepwear, and this created a situation in which almost aU chemical fire-retardant-treated textiles were unfairly condemned as dangerous. Manufacturers mshed to replace chemically treated textiles with products produced from inherently flame-resistant fibers. Nowhere was the impact more severe than in the children s sleepwear market. New, safer materials have been introduced to replace Tris. Thus far none has been as completely effective. 

It is well known that arsenic is one of the most dangerous elements in terms of its potential impacts to both to human and ecosystem health. Therefore the problem of As detection at ppb level remains very important from the point of environmental hazard investigation. The goal of the present work is the developing of very simple and inexpensive assay for arsenite and arsenate determination in environmental samples using whole-cell bacterial biosensors. 

In the first environment, we are concerned with the potential health risks that chemicals pose to the public, as well as possible impacts on the ecology. In the latter case, we are concerned with indoor air quality and its possible adverse impacts on the health and safety of the workforce. In both cases the health dangers may be either acute, or long-term chronic health risks. We will first discuss general concepts of air pollution and table our discussions on... 

Because the hazard is still present, there is always a danger that its potential impacts could be realized by some unanticipated route or mechanism. Nature may be more creative in inventing ways by which a hazardous event can occur than experts are in identifying them. Accidents can occur by mechanisms that were unanticipated or poorly understood. 

It is a powerful expl, as sensitive to impact as NG (BurMines drop test with 2kg wt, 4cm). Its Abel Test stability is about 20 minutes at 82°. MTN alone does not gelatinize NC unless the temp is raised to 110°, which would be dangerous, but if mixed with only 8% of the triacetate, it gelatinizes the NC at 80° Physical and chemical properties of MTN, detd primarily at Picatinny Arsenal, are as follows ... 

Note Sodium Picrate, Double Salts of. When an aq soln of Na picrate (3 moles) is stirred and heated with 3 moles of finely powdered Ba or Fb picrate, the resulting double salts are less sensitive to impact than the single salts (and for this reason are less dangerous to handle). The same can be said for other picrate double salts (Ref 4)... 

VasU ev (Ref 36) impacted various explosives with steel plates and followed events with a framing camera. PA at 1,59g/cc impacted with a 3-mm thick steel plate at 430m/sec showed only deflagration and no expins. Initially the burning rate was low but reached 600m/sec in about 65 microseconds after impact C. Potential Hazards. The main danger of accidental expln of PA appears to be in fires. There appears to be uncertainty if explns result if PA bums out of contact with metals. On p 494, Urbanski (Ref 35) states ... 

A common assumption is that reduced environmental impact must be paid for by higher prices or lower profit margins. This is a dangerous assumption because it reinforces the idea that environmental issues are a problem and cost. With good design you can achieve reduced impact and higher value at the same time. 

When it is heated above 196°C, the mixture of this compound with chromium trioxide combusts. When it is submitted to friction or impact, the same mixture detonates violently. The same happens if it is heated with sodium nitrite. Nitrite gives rise to a detonation with potassium hexacyanoferrate (II) too. The dangerous site of these complex anions is the cyano group. 

Mercuric and mercurous nitrates have the same oxidising properties as nitrates. The first has been involved in accidents with phosphine (formation of a complex, which detonates on impact) and alkaline cyanides. In the latter case, it is assumed that the danger arises from the formation of mercury nitrite, which is highly unstable in one particular accident the use of an apparatus with a narrow neck aggravated the effect, causing an effect of confinement. The second nitrate led to more or less strong detonations with carbon (red-hot) and phosphorus (on impact). 

Diisopropyl ether that is peroxidised detonated many times by stirring, unscrewing the cap, impact. All accidents are fatal due to the violence of the detonations. It peroxidises in a few hours and forms complex mixtures, which are highly dangerous. The following peroxides have been identified ... 

In a recent seminar, a medical expert noted that the United States has given away economic and technical dominance in industry after industry to other countries. Healthcare research is one of the few areas in which the U.S. enjoys unparalleled leadership which has enormous impact on the quality of medical care. If the healthcare industry and the academic medical enterprise falters—and this is in danger right now—I think it will be an absolute disaster for this country [40]. Many in pharmacy, medicine, and other healthcare fields would concur with the above statement. The problem is that many others in the public sector do not fully appreciate what is at stake. Pharmacists have an opportunity to help tell the story, as difficult as it sometimes is to convey. 

It is much harder to gauge the scale of impacts for the unconfined risks. The most dramatic, and probably most immediate, of the dangers are those from nuclear weapons. Even a small nuclear weapon of the Hiroshima size could cause 100,000 deaths and a large-scale nuclear war could involve hundreds of millions of deaths. It is difficult to judge whether nuclear power would make the use of nuclear weapons more or less likely, or even... 

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