Geògrafs: regeneracionisme i divisió del territori (1879-1899)

Després d'haver fet inviable qualsevol alternativa federal i un cop passats uns anys d'estabilització del nou regim alfonsí, la burgesia oligarquica es va sentir amb forces per iniciar un període de reformes que per fi la dotés d'una Administració territorial convenient als seus interessos. Des de 1879 fins a la meitat de la decada següent, s'inicia un període de relatiu optimisme en el que fa referencia a les reformes de !'Estat, fet que, com podrem observar, contrastara amb el sentiment fatalista de la dkcada de 1890, agreujat per la perdua de les colonies.

A Study of Portland Cement Maintenance Mix and Set Accelerators, R-249, 1970

The large volume of traffic on the interstate system makes it difficult to make pavement repairs. The maintenance crew needs 4-5 hours to break out the concrete to be replaced and prepare the hole for placing new concrete. Because of this it is usually noon before the patch can be placed. Since it is desirable to remove the barricades before dark there are only 7-8 hours for the concrete to reach the required strength. There exists a need for a concrete that can reach the necessary strength (modulus of rupture = 500 psi) in 7-8 hours. The purpose of this study is to determine if type III cement and/or an accelerator can be used in an M-4 mix to yield a fast setting patch with very little shrinkage. It is recognized that calcium chloride is a corrosive material and may therefore have detrimental effects upon the reinforcing steel. The study of these effects, however, is beyond the scope of this investigation.

Books, publications, project completion reports, M.S. and Ph. D. theses : research supported by Iowa State Water Resources Research Institute under the Water Resources Research Act of 1964, U.S. Public Law 88-379, U.S. Department of the Interior, Office of Water Resources Research, 1970

This book, published jointly by the American Society of Agronomy, Soil Science Society of American and Iowa State University presents the papers that were given at a symposium held in Ames, Iowa, on Nov. 30 and Dec. 1, 1965 on the general topic of plant environment and efficient water use.