Smoke reduction

Table 14. Oxygen Index and Smoke Reduction of Unsaturated Polyester Containing Molybdenum Oxide and Antimony Oxide...

General measures include stopping smoking, reduction of excessive alcohol intake and exploration and, if possible, resolution of any significant psychological factors. Pharmacological treatments are of limited efficacy. 

Many other reports have demonstrated the smoke suppressing tendencies of hydrated fillers in various polymers including ethylene-propylene-diene elastomers,43 PP,38 polystyrene,49 modified polyphenylene oxide, polybutylene terephthalate, and ABS.37 In addition to suppressing smoke generation, a delay in the onset of smoke evolution is also achievable.25 Figure 7.5 illustrates smoke reductions obtained in PP. 

The analysis of smoke and soot formation from polymers during combustion has been extensively studied 50,51 however, less is understood on how hydrated fillers influence this mechanism. It is likely that smoke reduction results from the deposition of carbon onto the high surface area oxide surface, produced on the decomposition of the filler.38 The volatilization of carbonaceous residue as carbon oxides then occurs, reducing obscuration effects from the smoke. 

Polyvinyl Chloride (PVC) In flexible PVC, the partial replacement of antimony oxide with the zinc borate cannot only display synergy in flammability test performance but also results in dramatic smoke reduction.56 This synergy can be more dramatic when used in conjunction with ATH or magnesium hydroxide (MDH) (Figures 9.4 through 9.6). A recent Cone Calorimeter study49 showed that, in flexible PVC, the partial replacement of antimony with the zinc borate could reduce both the HRR and carbon monoxide production drastically at a... 

Magnesium Magnesium hydroxide Magnesium carbonate Synergists with ATH for smoke reduction Addenda, Albemarle-Martinswerk, Amspec Chemical, Dead Sea Periclase, DSBG, J.M. Huber, Kyowa Chemical Industry, Sumitomo Chemical, Witttaker... 

Vapors containing alkali metal species have diverse implications to high temperature processes (1 ). Potential new applications of alkalies in combustion systems include—their vapor phase catalytic action in smoke reduction (2, 3), their liquid phase catalysis of coal gasification (4), and their role as electron sources for magnetohydrodynamic (MHD) combustion systems (3). In most combustion systems, however, their presence is undesirable. This is particularly true in fossil energy systems. 

Lichtenstein E, Boles SM, Lee ME, et al. Using radon risk to motivate smoking reduction II Randomized evaluation of brief telephone counseling and a targeted video. Health Educ Res 2007 [available online only as of time of publication, access via PubMed, www.ncbi.nlm.nih.gov/sites/entrez... 

Smokers should stop smoking completely while using any NRT product, although some products are licensed for use for smoking reduction before a quit attempt. 

Sugiura, K. and Kagaya, M. (1977) A study of visible smoke reduction from a small two-stroke engine using various engine lubricants. SAE Paper 770623. 

Primary Smoking reduction programmes to control lung cancer, ischaemic heart disease, chronic bronchitis and other diseases Environmental control of chemicals that cause asthma... 

Large amounts of thioq anate are generated in people with a high intake of cyanide from tobacco smoking, from cyanide in food, or from industrial pollution of the environment with cyanide. Thiocyanate may also be directly consumed with certain foods. Thiocyanate is a competitive inhibitor of the sodium iodide symporter (NIS) at thiocyanate levels normally found in blood. Thereby, it worsens iodine deficiency by inhibition of thyroidal iodide accumulation and by inhibition of iodide transport into breast milk for infant nutrition. Cessation of smoking, reduction of industrial pollution and improved diet will reduce the role of thiocyanate in thyroid disease. In individuals exposed to high levels of thiocyanate, adverse effects may be prevented by an increase in iodine intake. 

Figure 3.40. Smoke reduction vs. concentration of three smoke suppressants. [Data from Carty, P Grant, J. Metcalfe, Ji.,Appl. Organometallic Chem., 10,2,101-11,1996.]...

B. Chehroudi, K.M. Sinko, W.J. Minkowycz, S. Shih Interacting-spray injection a new concept for NOx and smoke reduction in diesel engines. Atomization and Sprays, 8, 673-690 (1998). 

Kroenke and Lattimer " established a relationship between smoke reduction, char formation and the ability of smoke suppressors to greatly reduce the yield of aromatic hydrocarbons during pyrolysis. 

The first commercial smoke suppressant that was effective at a low proportion was the Ferrocene FE-55 of Arapahoe. However, its brown colour restricted its utility. It is still recommended for rigid PVC and rigid PUR foams, where a smoke reduction of 20 to 60 per cent is reached at a load of 0.25 to 0.75 phr (phr parts per hundred, i.e, parts to 100 parts of the principal component, the polymer). ... 

Guyot, A., Michel, A., Bert, M. and Tran Van Hoang Basic studies of smoke reduction in rigid poly(vinyl chloride). J. Vinyl TechnoL, 3, 189 (1981)... 

Use of nanoclay can be an initiative for preparation of PVC composites. Walid et al. have studied the preparation of poly(vinyl chloride) nanocomposites (Figure 6.11) using organically modified clays such as lecto-rite and bentonite and concluded that addition of a calculated amount of modified bentonite (or) hectorite nanoclay material leads to smoke reduction as well as enhances the time span of smoke evolution [31,32]. 

Zinc borates have also found uses in PVC formulations. They have been shown to be effective flame/smoke suppressants when used as partial replacements for the antimony oxide that is normally used in a t3 ical flexible PVC cable jacket, for example. For flexible vinyl and PVC plastisol formulations, a half to two-thirds of the antimony trioxide can be replaced by zinc borate without loss of flame retardancy. If a small decrease in flame retardancy can be tolerated, all of the antimony trioxide can be replaced with zinc borate, leading to smoke reductions of up to 65%. The flame retardancy can be increased and smoke formation decreased by adding aitunonium octamolybdate to the borate-containing formulations. 

In PVC partial replacement of antimony oxide not only provides synergy for flame retardancy, but also improves smoke reduction, which can be enhanced by addition of ATH. Just as important, due to antimony oxides costing more, partial replacement by zinc borate can result in considerable savings on cost, usually between 30 and 60%. Total replacement of antimony oxide in the presence of a halogen containing system is possible. In polyamide, Firebrake ZB plus a compound like OxyChem s Dechlorane Plus maintains a V-0 rating in the UL94 tests. 

E. M. Bulewicz and P. J. Padley, Suggested origin of the anomalous line-reversed temperatures in the reaction zone of hydrocarbon flames. Combust. Flame 5, 331-340 (1961). K. S. B. Addecott and C. W. Nutt, Mechanism of smoke reduction by metal compounds, presented at 158th National Meeting of American Chemical Society, New York, September 7-12, 1969. 

Placebo-controlled studies In a doubleblind, placebo-controlled study of smoking reduction in 60 smokers, who were given baclofen titrated upwards to 20 mg qds, the most common adverse reaction during baclofen treatment was transient drowsiness however, there were no differences between the groups in mild, moderate, or severe sedation [42 ]. 

Franklin TR, Harper D, Kampman K, Kildea-McCrea S, Jens W, Lynch KG, O Brien CP, Childress AR. The GABAb agonist baclofen reduces cigarette consumption in a preliminary double-blind placebo-controlled smoking reduction study. Drug Alcohol Depend 2009 103(1-2) 30-6. 

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