Geology and ground-water resources of Cerro Gordo County, Iowa, 1970

The purposes of this report are to delineate and describe aquifers in Cerro Gordo County, evaluate the availability and quality of water in the aquifers, supply data on ground-water utilization, and determine the rate of growth and the magnitude of the cone of drawdown in the Mason City area. It includes photos and fold-out maps

Scale Effects in Hydraulic Model Tests of Rock Protected Structures, HR-119, 1970

A laboratory investigation was undertaken to determine the limiting model Reynolds number above which the scour behavior of rock protected structures can be reproduced in hydraulic models scaled according to the Froude criterion. A submerged jet was passed over an initially full scour pocket containing uniform glass spheres and the rate of scour was measured as a function of time. The dimensions of the scour pocket and jet and the particle diameters were varied as needed to maintain strict geometric similarity. For each of two different Froude numbers the Reynolds number was varied over a wide range. The normalized scour rate was found to be practically independent of the Reynolds number, R, (based on the jet velocity and particle diameter) at values of R above about 2.5 x 10^3, and to decrease with Rat smaller values. A grid placed in the jet was found to have a very strong effect on the scour rate. In an attempt to explain the effect of R on the scour behavior, turbulent pressure and velocity fluctuations were measured in air flows and water flows, respectively, over rigid scour pockets having the same geometry as those formed in the scour experiments. The normalized spectra of the fluctuations were found to be nearly independent of R, but the flow pattern was found to be very sensitive to the inlet condition, the jet deflecting upward or downward in a not wholly explainable manner. This indicates that scour behavior can be modeled only if the approach flow is also accurately modeled.

Los hombres nuevos. Un paralelismo entre la filosofía de la liberación y la Junta de Coordinación Revolucionaria en las décadas de 1960 y 1970

La segunda mitad del siglo XX fue testigo de una crisis intelectual originada comoconsecuencia de una situación política y económica también crítica, en un contexto detensión internacional orquestado por la Guerra Fría. Los intelectuales, que comprendíansu situación histórica como una llamada ética a la responsabilidad, mantuvieron ciertasdudas ante su compromiso político y, aún más, revolucionario. Esto se dio de modomanifiesto en América Latina en torno a las décadas de 1960 y 1970, donde sedesarrollaron, paralelamente, una corriente filosófica con pretensiones de liberación queera fruto de la preocupación por la autenticidad latinoamericana y un movimientogeneralizado de lucha armada protagonizado por diversas organizaciones guerrilleras.

Ajan hengen lyhyt historia : Suomen Etnomusikologinen Seura 1970-80-lukujen vaihteessa

Suomen Etnomusikologisen Seuran 30-vuotisjuhlaseminaarissa pidetty esitelmä.

Summary of Legislation: Iowa General Assembly, 1970

This summary of legislation enacted by the General Assembly has been prepared for the use of legislators and other interested parties. The summary of each legislative enactment has been assigned to a major subject category. This compilation provides interested persons with quick reference to legislation enacted in specific areas and generally informs persons of the contents and effective date of the legislation. NOTE: This is a large file and may take a few minutes to load.

The Iowa scene, 1970

This paper was prepared for presentation at the Workshop for Iowa School Superintendents, June 8, 1970. Contains information and graphs on population changes of towns, employment estimates, farm and manufacturing impacts and 1980 projected populations.

Public libraries: adapting to the digitised environment. An interview with John Lake

During John Lake's visit to Barcelona to take part in a seminar organized by the Facultat de Biblioteconomia i Documentació (Department of Library and Information Science) at the University of Barcelona (UB)1 EPI sought an interview to further explore some of the themes addressed in the seminar, drawing on his extensive experience in the world of public libraries.

The Prediction of Creep and Shrinkage Properties of Concrete, HR-136, 1970

This report is concerned with the prediction of the long-time creep and shrinkage behavior of concrete. It is divided into three main areas. l. The development of general prediction methods that can be used by a design engineer when specific experimental data are not available. 2. The development of prediction methods based on experimental data. These methods take advantage of equations developed in item l, and can be used to accurately predict creep and shrinkage after only 28 days of data collection. 3. Experimental verification of items l and 2, and the development of specific prediction equations for four sand-lightweight aggregate concretes tested in the experimental program. The general prediction equations and methods are developed in Chapter II. Standard Equations to estimate the creep of normal weight concrete (Eq. 9), sand-lightweight concrete (Eq. 12), and lightweight concrete (Eq. 15) are recommended. These equations are developed for standard conditions (see Sec. 2. 1) and correction factors required to convert creep coefficients obtained from equations 9, 12, and 15 to valid predictions for other conditions are given in Equations 17 through 23. The correction factors are shown graphically in Figs. 6 through 13. Similar equations and methods are developed for the prediction of the shrinkage of moist cured normal weight concrete (Eq. 30}, moist cured sand-lightweight concrete (Eq. 33}, and moist cured lightweight concrete (Eq. 36). For steam cured concrete the equations are Eq. 42 for normal weight concrete, and Eq. 45 for lightweight concrete. Correction factors are given in Equations 47 through 52 and Figs., 18 through 24. Chapter III summarizes and illustrates, by examples, the prediction methods developed in Chapter II. Chapters IV and V describe an experimental program in which specific prediction equations are developed for concretes made with Haydite manufactured by Hydraulic Press Brick Co. (Eqs. 53 and 54}, Haydite manufactured by Buildex Inc. (Eqs. 55 and 56), Haydite manufactured by The Cater-Waters Corp. (Eqs. 57 and 58}, and Idealite manufactured by Idealite Co. (Eqs. 59 and 60). General prediction equations are also developed from the data obtained in the experimental program (Eqs. 61 and 62) and are compared to similar equations developed in Chapter II. Creep and Shrinkage prediction methods based on 28 day experimental data are developed in Chapter VI. The methods are verified by comparing predicted and measured values of the long-time creep and shrinkage of specimens tested at the University of Iowa (see Chapters IV and V) and elsewhere. The accuracy obtained is shown to be superior to other similar methods available to the design engineer.