Special Libraries, April 1956

Volume 47, Issue 4https://scholarworks.sjsu.edu/sla_sl_1956/1003/thumbnail.jp

A REVIEW ON THE MATERIALS USED FOR BEARING AND FAILURE BEHAVIOR

This paper highlights the metallic, polymeric and ceramic materials used to manufacture the bearings, the kind of failures experienced with those materials and their causes. The failure mechanism of bearings and influence of various elements on their properties are reviewed. It is identified from the study that the failure is mainly provoked by initiating the surface micro crack/flake and then subsequently propagating them to failure. Materials influencing wear resistance to control the material removal rate without much compromising the fracture toughness are discussed. The advanced composite materials used in bearings are also discussed. A review on nano composites is also done to turn out the research on bearing materials towards nano composites. The evolution of MMC, nano-composites is investigated to come to a conclusion on stimulating a research work to make a better material for bearings at room temperature and cryogenic temperature. A suitable polymer material is suggested for carrying out the research at cryogenic temperature for low temperature application of bearings

Ex Libris, Spring 2005

WVU Libraries to Host Exhibit Highlighting Women in Medicin

A REVIEW ON THE MATERIALS USED FOR BEARING AND FAILURE BEHAVIOR

This paper highlights the metallic, polymeric and ceramic materials used to manufacture the bearings, the kind of failures experienced with those materials and their causes. The failure mechanism of bearings and influence of various elements on their properties are reviewed. It is identified from the study that the failure is mainly provoked by initiating the surface micro crack/flake and then subsequently propagating them to failure. Materials influencing wear resistance to control the material removal rate without much compromising the fracture toughness are discussed. The advanced composite materials used in bearings are also discussed. A review on nano composites is also done to turn out the research on bearing materials towards nano composites. The evolution of MMC, nano composites is investigated to come to a conclusion on stimulating a research work to make a better material for bearings at room temperature and cryogenic temperature. A suitable polymer material is suggested for carrying out the research at cryogenic temperature for low temperature application of bearings

The Production of Activated Carbon From North Dakota Leonardite

The utilization of leonardite for the production of granular activated carbons was investigated. In granular activated carbons it is desirable to have hard dense granules to permit use without excessive disintegration. Two methods were used to modify the leonardite structure in order to obtain better granules. In one method the leonardite was put into colloidal suspension with certain alkalis. Chemicals were then added to the suspension. The additives used were calcium hydroxide, phosphoric acid, and calcium carbonate. This material was then granulated by drying. The second method for preparing granules consisted in pelletizing powdered leonardite in a rotary drum using a fine spray of sodium hydroxide solution. The chemical additives used in this method were pitch, zinc chloride and phosphoric acid. These granules were then dried, carbonized and activated. Activation was carried out in a rotary tube furnace using steam as an activating agent. For leonardite char fed at 534 grams per hour the optimal activation conditions for methylene blue adsorption were found to be 950° C. with a steam rate of 300 grams per hour. Methylene blue and heat of wetting tests indicated that leonardite char when activated generally had more adsorptive power than the colloidally prepared carbons and had less adsorptive power than the pelletized carbons. The carbon with the greatest adsorptive capacity was a pelletized carbon with a zinc chloride additive. For methylene blue adsorption it was equal to Darco grade S-51 and about 60 per cent as efficient as Columbia grade G. The hardness and abrasion resistance of the prepared carbon were inferior to that of the commercial carbons

Defense contracting

Thesis (M.B.A.)—Boston University

Spiderworms: Using Silkworms as Hosts to Produce a Hybrid Silkworm-Spider Silk Fiber

Spider silk has received significant attention due to its fascinating mechanical properties. Given the solitary and cannibalistic behavior of spiders, spider silk farming is impractical. Unlike spiders, silkworms are capable of producing large quantities of a fibrous product in a manner mimetic to spiders, and there already exists an industry to process cocoons into threads and textiles for many applications. The combination of silk farming (sericulture), a millennia old practice, and modern advancements in genetic engineering has given rise to an innovative biomaterial inspired by nature; transgenic silkworm silk. This project focuses on the creation of chimeric silkworm-spider silk fibers through the genetic modification of silkworms. Advanced genetic engineering techniques were used to introduce the minor ampullate spider silk (MiSp) genes into the silkworm genome. A subset of these transgenic silkworms was cross-bred with other transgenic silkworms containing the same spider silk gene in a different section of the silkworm genome to create hybrid, dual-transgenic silkworms. The transgenic silk samples showed increased mechanical properties compared to native silkworm fibers, with the strongest fibers approaching or surpassing the mechanical properties of native spider silk. The transgenic silk retained the elasticity of the native silkworm silk and gained the strength of the spider silk. Ultimately, genetic engineering opens the door to mass produce synthetic spider silk in an established organism and industry, and the results of this project demonstrate that the properties of silkworm silk can be predictably altered through this technology