3 resultados para Chancer, Lynn S
em Digital Commons - Montana Tech
Resumo:
In August 1977 excavation was conducted at the Big Creek Lake site -24RA34- at the outlet of the 91g Creek Lakes, Selway-Bitterroot Wilderness Area, Ravalli County, Montana. The site contained shallow, disturbed deposits and lacks any statisgraphic separation. One of these occupations was identified by a projectile point type not previously reported from the area. This was termed Big Creek Corner Notched and its temporal affiliation is not precisely known. Comparative material from Colorado and Alberta suggest either Early Archaic or Late Archaic affiliation. The occupations exemplified by Big Creek Corner Notched points and by Pelican Lake-Elko points (Late Archaic 1000 B.B – A.D. 200) were the most prevalent at the site. Less intensive occupations are by ·Middle Plains Archaic McKean points and Late Prehistoric small side notche arrow points. Microscopic analysis of tool working edges shows several of the projectile point forms were used as multi-functional implements. especially as butchering tools. Many of the types of chipped stone recovered from the site are from known sources in western Montana; indicating group movements within the eastern portion of the Intermountain region. Based on the numerous projectile points and cutting tools, the site is interpreted as a seasonally occupied base camp for hunters.
Resumo:
Warnings are used to inform users of hazards that may be associated with many products. Often these warnings deal with the operation of tools, appliances, and other items for which the user may have some reason at least, to look for information on the product regarding its use. Plastic film presents a serious hazard to young children. Because the film will adhere to the flesh, if it covers the airways for the child, suffocation may result. Because young children may play with them, it is important that such films be kept away from them. Warnings need to be adequate to inform or remind caregivers of this fact. This study examined warnings found on various items in commerce and some alternatives to those warnings. The results showed some warnings to be poor at best. The alternative most preferred included both the prohibition sign and a symbolic indication of proper disposal.
Resumo:
Cyclic Voltammetry experiments have been conducted on copper, iron, and chalcopyrite (CuFeS2) and compared to mass-balanced EH-pH Diagrams. Potassium ethyl xanthate (KEX) was added to solution and additional voltammetry experiments were performed to determine the surface chemistry reactions of flotation collector in solution with these minerals. The ultimate goal of this research was to investigate the possibility of xanthate chemisorption onto the chalcopyrite mineral surface. Results of the copper mineral testing confirm previous literature studies and corroborate published isotherm data. Results of the iron mineral testing showed changes in surface reactions with the addition of potassium ethyl xanthate to solution, however, these results were not attributed to the chemisorption of xanthate. Results of the chalcopyrite mineral testing indicate that the surface of the mineral oxidizes to chalcocite (Cu2S). In the presence of ethyl xanthate, small currents were observed and attributed to chemisorption of the potassium ethyl xanthate at the chalcocite surface, suggesting that the mineral's hydrophobicity is induced by more than dixanthogen. This phenomenon was found to be pH-dependent under a range of alkaline conditions (i.e., pH 7-12) at narrow potentials (i.e., 0 to -200mV).