Volatilization temperature

Ground turbine fuels are not subject to the constraints of an aircraft operating at reduced pressures of altitude. The temperature of fuel in ground tanks varies over a limited range, eg, 10—30°C, and the vapor pressure is defined by a safety-handling factor such as flash point temperature. Volatile fuels such as naphtha (No. 0-GT) are normally stored in a ground tank equipped with a vapor recovery system to minimise losses and meet local air quaUty codes on hydrocarbons. 

Volatile A volatile substance is one that is capable of being evaporated or changed to a vapor at a relatively low temperature. Volatile substances also can be partially removed by air stripping. 

Despite the difficulties, there have been many efforts in recent years to evaluate trace metal concentrations in natural systems and to compare trace metal release and transport rates from natural and anthropogenic sources. There is no single parameter that can summarize such comparisons. Frequently, a comparison is made between the composition of atmospheric particles and that of average crustal material to indicate whether certain elements are enriched in the atmospheric particulates. If so, some explanation is sought for the enrichment. Usually, the contribution of seaspray to the enrichment is estimated, and any enrichment unaccounted for is attributed to other natural inputs (volcanoes, low-temperature volatilization processes, etc.) or anthropogenic sources. 

The alkylating agent (0.1 mol) is added to the TBA salt of the methylene compound (0.05 mol) in CHCI, (75 ml) and the slightly exothermic reaction is stirred at room temperature. Volatile material is evaporated and Et20 (25 ml) is added to the residue. The filtered ethereal solution is evaporated to yield the alkylated product. 

Nylon microwave and roasting bags were reported to release, at cooking temperatures, volatile compounds, such as Nylon 6,6 cyclic monomer and cyclic oligomers up to the tetramer, and Nylon 6 monomer and cyclic oligomers up to the octamer. The same non-volatile compounds (except Nylon 6 heptamer and octamer) were extracted from the same packages (Soto-Valdez et al., 1997). 

The Isometric ion plots of Figures A and 5 indicate that evolution of benzene from the silicone-epoxy samples occurs in two distinct stages, with the low temperature peak attributable to residual solvent species. Above 200°C, thermal degradation processes involving scission of the Si-phenyl bond occur and account for the increased formation rate of benzene. The other high temperature volatile products are similar to those observed for the novolac epoxy samples, and are attributed to decomposition of the epoxy fraction of samples D and E. 

Smith, M. H., and C. D. O Dowd, Observations of Accumulation Mode Aerosol Composition and Soot Carbon Concentrations by Means of a High-Temperature Volatility Technique, J. Geophys. Res., 101, 19583-19591 (1996). 

In many high temperature applications in the electrical and electronics industry, the refractory metals arc protected by a vacuum or an inert gas, so that oxidation is not a problem. However, for most other high temperature applications, poor oxidation resistance has limited use. The oxides ol [he refractory metals, rather than existing as tight, protective barriers, stiller from porosity at moderately elevated temperatures, volatility at higher temperature, and spalling of ihe oxide scales away from the substrate, especially al corners and edges. 

The widely used Parylene C owes its popularity principally to the room temperature volatility of its monomer. The Parylene C monomer, chloro-/>-xylylene, has become the de facto performance standard. By comparison, the Parylene N monomer, -xylylene itself, is too volatile and would perform better in a sub-ambient temperature deposition system. The Parylene D monomer, dichloro-p-xy 1 Iene [85586-88-5] is too heavy, and causes distribution problems in larger deposition systems. 

A solvent is a substance that can dissolve another substance, and a volatile solvent is a liquid that vaporizes at room temperature. Volatile solvents include adhesives such as airplane glue and rubber cement aerosols such as spray paint, hair spray, and air freshener solvents such as nail polish remover, paint remover, and lighter fluid and cleaners such as dry cleaning fluid, spot remover, and degreasers. 

To an ice-cooled solution of N-methyl-l-naphthalenemethylamine hydrochloride (2.1 g) in methanol (40 ml) and water (10 ml) was added sodium hydroxide powder (2 g) followed by dropwise addition of epichlorohydrin (8 ml). The mixture was heated at 60°C for 3 h, then cooled to room temperature. Volatile materials were removed in vacuo and the residue was taken up in ethyl acetate and washed with water. The organic phase was collected, dried over sodium sulfate, filtered and evaporated to dryness. The crude mixture was purified by flash chromatrography on silica gel (grade 9385, Merck, 230-400 mesh, 60 A) using a solvent gradient of a mixture of hexane and ethyl acetate (95 5, 90 10 and 85 15) as eluent, affording the N-methyl-N-naphthylmethyl-2,3-epoxypropane (1.85 g, 81.5%) as an oil. 

The reaction mixture is allowed to warm slowly to room temperature over a 15 to 20-minute period, during which time the reaction mixture is periodically stirred with a small magnet. While the reaction mixture is wanning to room temperature, volatile reaction products are removed at a rate so as to maintain gentle reflux on the —78.5° cold finger. The reaction is complete when the reactor reaches room temperature. 

Mercury Input to the Oceans via Submarine Volcanism Low-temperature Volatilization Anthropogenic Sources Mining... 

There are three prominent processes that release mercury of mixed natural and anthropogenic origin to the atmosphere. These three include biomass burning (deliberate and natural) and the evasion of mercury from soils and the ocean. The general factors controlling emission of mercury from soils have been discussed in the section on low-temperature volatilization. The mercury... 

Although the OSl method is useful for quality control of oils, it is not recommended for measurement of antioxidant activity for certain reasons. The high temperatures used do not allow reliable predictions of antioxidant effectiveness at lower temperatures. Volatile antioxidants may be swept out of the oil by the air flow under test conditions, and also the oils are severely deteriorated when endpoint is reached (12). 

The discussion of the essential features in the experimental and theoretical approaches to the free radical degradation of polymers is thus completed. We introduce the next section with a summary table which is subdivided according to the two extremes of degradation unzipping and random scission. The first part of Table III describes the influence of basic structure and the second deals with secondary factors for a given structure. When a polymer is processed at elevated temperatures, volatilization and deterioration of physical properties during short time intervals are a matter of concern hence initial rates are important. 

At the reaction temperatures involved, molten nitrate systems are not particularly corrosive and conventional materials, such as stainless steels, are probably adequate for the reaction, dissolution, and separation steps. If high-temperature volatilization or transfer to a halide system is necessary, then other materials will be required. 

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