Copper Complexation by Dissolved Organic Matter in arid Soils: A Voltametric Study

A voltammetric method was used to estimate the complexing capacity of water extracts from both desert soils sampled at the root zone of creosote and salt cedar plants, and in soils from interspace or background regions where no vegetative influence was apparent. The copper complexing capacity of water extracts of these desert soils was influenced by contact time and pH. In soils from the root zones of creosote and salt cedar plant, copper complexation capacities at pH 8 were from 5 µM to 60 µM after five min contact periods, while 18 h contact periods yielded copper complexation capacities of 40 µM–80 µM. Soils with no vegetative influence had copper complexing capacities of less the 2 µM. The copper complexing capacities of these soils are well correlated with the concentration of organic carbon in the water extract (r2 = 0.86). The abundance of soluble organic matter in the root zone of desert shrubs has the potential to control the solution speciation of Cu2+. The formation of soluble complexes should also have an important influence on the plant uptake and transport of copper, as well as other heavy metals in the root zones of desert shrubs and beyond

Flat plate collector performance determined experimentally with a solar simulator

The NASA is constructing a new office building at Langley Research Center that will utilize solar energy for heating and cooling. A collector technology program being conducted at Lewis will provide the basis for selecting collectors for use at Langley. The technology program includes testing collectors in an indoor facility under simulated solar radiation. Tests have been conducted on five collectors to date and performance data are presented herein

Lost Directions: U.S. Foreign Assistance Policy Since New Directions

International Development,

ECONOMICS OF SOME SWINE PRODUCTION SYSTEMS WITH REFERENCE TO ANIMAL WELFARE

Livestock Production/Industries,

A Comparative Study of Social Behavior of Children: Kindergarten Through Grade Three as Identified by Teacher Rankings, the California Test of Personality and the Hewett Teacher Rating Scale

The purpose of this study was to investigate the soundness of teacher rankings and ratings. This investigation was made by comparing teacher rankings, the Hewett Teacher Rating Scale and the California Test of Personality. To this end the major purposes of this study were: 1. to determine the relationship that exists between teacher ranking of children in three areas of social behavior: socially adjusted behavior, antisocial behavior, and withdrawn behavior and scores of the child on the related subsections of the California Test of Personality. to determine the relationship that exists between the teacher ranking of children on the above three areas of social behavior and the teacher ratings of the child on individual items of the Hewett Teacher Rating Scale. Procedure The research population consisted of 882 students. Of the research population 687 were identified by the thirty teachers in the study as being in the upper twenty-seven per cent or the lower twenty-seven per cent of the teacher rankings. Teachers ranked their children in three categories of social behavior. The three categories used were: socially adjusted behavior, antisocial behavior, and withdrawn behavior. Statistical procedure used included multiple correlation and stepwise backward elimination. Categorical predictors included, teacher ranking of socially adjusted behavior, teacher ranking of antisocial behavior, and teacher ranking of withdrawn behavior. Results and Conclusions 1. Teachers are able to recognize children that manifest socially adjusted behavior.2. A high degree of relationship can be ascertained between socially adjusted behavior, academic achievement, and individual items of the Hewett Teacher Rating Scale.3. Teachers have some difficulties in discriminating between “antisocial behavior and withdrawn behavior

Propfan experimental data analysis

A data reduction method, which is consistent with the performance prediction methods used for analysis of new aircraft designs, is defined and compared to the method currently used by NASA using data obtained from an Ames Res. Center 11 foot transonic wind tunnel test. Pressure and flow visualization data from the Ames test for both the powered straight underwing nacelle, and an unpowered contoured overwing nacelle installation is used to determine the flow phenomena present for a wind mounted turboprop installation. The test data is compared to analytic methods, showing the analytic methods to be suitable for design and analysis of new configurations. The data analysis indicated that designs with zero interference drag levels are achieveable with proper wind and nacelle tailoring. A new overwing contoured nacelle design and a modification to the wing leading edge extension for the current wind tunnel model design are evaluated. Hardware constraints of the current model parts prevent obtaining any significant performance improvement due to a modified nacelle contouring. A new aspect ratio wing design for an up outboard rotation turboprop installation is defined, and an advanced contoured nacelle is provided