Fresh News; The Farmers' Market Newsletter, Winter 2006

Newsletter produced by Iowa Department of Agriculture and Land Stewardship

Fresh News; The Farmers' Market Newsletter, Spring 2006

Newsletter produced by Iowa Department of Agriculture and Land Stewardship

After the Ban: The Japanese Market for U.S. Beef, April 2007

In the months following the reopening of the Japanese market to imports of U.S. beef on July 26, 2006, Japanese importers were unable to procure adequate supplies. This paper discusses reasons for early supply shortages and some of the policy and trade issues that will affect demand for U.S. beef in the short to medium term. The paper also discusses current marketing efforts for domestic and imported beef, new marketing technologies, and general consumer trends. The information presented in this paper includes on-site observations and data from meetings with Japanese importers and retailers and industry experts during market research in Tokyo and Osaka in November 2006.

Time-Temperature Strength-Reaction Product Relationships in Lime-Bentonite-Water Mixtures, HR-111, 1965

The interrelation of curing time, curing temperature, strength, and reactions in lime-bentonite-water mixtures was examined. Samples were molded at constant density and moisture content and then cured for periods of from 1 to 56 days at constant temperatures that ranged from 5C to 60C. After the appropriate curing time the samples were tested for unconfined compressive strength. The broken samples were then analyzed by x-ray diffractometer and spectrophotometer to determine the identity of the reaction products present after each curing period. It was found that the strength gain of lime-clay mixtures cured at different temperatures is due to different phases of the complex reaction, lime & clay to CSH(gel) to CSH(II) to CSH(I) to tobermorite. The farther the reaction proceeds, the higher the strength. There was also evidence of lattice substitutions in the structure of the calcium silicate hydrates at curing temperatures of 50C and higher. No consistent relationship between time, temperature, strength, and the S/A ration of reaction products existed, but in order to achieve high strengths the apparent C/S ration had to be less than two. The curing temperature had an effect on the strength developed by a given amount of reacted silica in the cured lime-clay mixture, but at a given curing temperature the cured sample that had the largest amount of reacted silica gave the highest strength. Evidence was found to indicate that during the clay reaction some calcium is indeed adsorbed onto the clay structure rather than entering into a pozzolanic reaction. Finally, it was determined that it is possible to determine the amount of silica and alumina in lime-clay reaction products by spectrophotometric analysis with sufficient accuracy for comparison purposes. The spectrophotometric analysis techniques used during the investigation were simple and were not time consuming.