Virgin Numbers

Isomerization. Isomerization is a catalytic process which converts normal paraffins to isoparaffins. The feed is usually light virgin naphtha and the catalyst platinum on an alumina or zeoflte base. Octanes may be increased by over 30 numbers when normal pentane and normal hexane are isomerized. Another beneficial reaction that occurs is that any benzene in the feed is converted to cyclohexane. Although isomerization produces high quahty blendstocks, it is also used to produce feeds for alkylation and etherification processes. Normal butane, which is generally in excess in the refinery slate because of RVP concerns, can be isomerized and then converted to alkylate or to methyl tert-huty ether (MTBE) with a small increase in octane and a large decrease in RVP. 

The caprolactam obtained must meet die specifications of permanganate number, volatile bases, hazen color, UV transmittance, solidification point, and turbidity in order to be used for repolymerization alone or in combination witii virgin CL.5 Reported CL purification methods include recrystallization, solvent extraction, and fractional distillation. One solvent extraction technique involves membrane solvent extraction. Ion exchange resins have been shown to be effective in the purification of aqueous caprolactam solutions. In one such process,... 

Endosulfan has been identified in at least 164 of the 1,577 hazardous waste sites that have been proposed for inclusion on the EPA National Priorities List (NPL) (HazDat 2000). However, the number of sites evaluated for endosulfan is not known. The frequency of these sites can be seen in Figure 5-1. Of these sites, 87 are located in the United States, one is located in Guam, and one is located in the Virgin Islands (not shown). 

The Center for Disease Control publishes an Annual Survey of Foodborne Disease for the fifty states, Guam, Puerto Rico and the U. S. Virgin Islands. The number of confirmed outbreaks listed for 1976 through 1980 ranged from three to 19 per year. The number of outbreaks listed for 1980 (10), the latest available survey, was at the high end, namely 15 and involved 52 individuals. Please note fifteen outbreaks and 52 individuals. 

Figure 1. The study area in the British and United States Virgin Islands. Dots indicate sites surveyed prior to establishing permanent collecting stations. Seven permanent stations are indicated by number.

Table I. Southern Illinois University (SIU) Culture Collection of Dinoflagellates From the Virgin Islands. All Stock Cultures are Maintained in ES Enriched Natural Seawater Containing 1.5% Soil Extract. The Letter c Next to Strain Number Denotes Clonal Culture.

The ACV is defined as the number of acid equivalents expressed as mg KOH per g of sample. It may be also expressed as percentage (m/m) of a particular fatty acid in a fat or oil. This parameter usually indicates alterations undergone by hydrolysis, and can be determined by direct titration " . The ACV is used as a standard, for example, ISO 660 or lUPAC 2.201 . The acidity of refined oils is always below 1%, whereas that of virgin oils is higher and variable. In cases of extreme oxidation, free carboxylic acids are produced (Scheme 1, Section ll.A.2.c) that contribute to the ACV. This is the operational principle on which the Rancimat equipment for POV determination is based. 

Aviation gasoline contains a high concentration of alkylate and high-octane-number aromatics. Careful fractionation of virgin naphtha can also be performed to isolate isohexane and isoheptane fractions. Aromatic components are limited by their calorific value and are typically C and Cg. 

Males respond better at intermediate (25 °C) than at more extreme temperatures (10 °C, 30 °C) (Appel and Rust, 1983). Fecal extracts from females reared at low temperatures elicited significantly less male courtship, suggesting that females produce less pheromone at the lower temperatures than at the higher temperatures (Appel and Rust, 1983). However, because females at low temperatures also defecate less, it is possible that while the total amount of pheromone was lower, the amount of pheromone per unit mass of feces may be the same as at 25 °C or 30 °C. Wharton etal. (1954) indicated that isolated males were much less responsive than grouped males, but Takahashi and Kitamura (1972) demonstrated that isolation from females for more than 1 month caused the males to be highly responsive. Adult males can survive at least a month without food. When food and pheromone (extract of filter paper that had been contaminated by virgin females) were presented separately to starved males, equal numbers of males responded to both stimuli, but when they were offered simultaneously, males preferred the pheromone (McCluskey etal, 1969). 

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