3,594 research outputs found
Tests of N.A.C.A. airfoils in the variable-density wind tunnel Series 24
This note is the fifth of a series covering an investigation of a number of related airfoils. It presents the results obtained from tests of a group of six low-cambered airfoils in the variable-density wind tunnel. The mean camber lines are identical for the six airfoils and are of such a form that the maximum mean camber is 2 per cent of the chord and is at a position 0.4 of the chord behind the loading edge. The airfoils differ in thickness only, the maximum-thickness/chord ratios being 0.06, 0.09, 0.12, 0.15, 0.18, and 0.21. The results have been presented in the form of both infinite and finite aspect-ratio characteristics. The values of C(sub L) max/C(sub d) degrees min for this group of airfoils are among the highest thus far obtained, the minimum profile drags being approximately equal to those for the symmetrical series of corresponding thickness, while the maximum lift coefficients are considerably higher
Cities on the Saco
Review of: Cities on the Saco: A Pictorial History. By Jacques M. Downs. Photo reproductions by Taylor H. Conrad
The âGreen Eatingâ Project: A Pilot Intervention to Promote Sustainable and Healthy Eating in College Students
The âGreen Eatingâ Project: A Pilot Intervention to Promote Sustainable and Healthy Eating in College Students
Kelleigh Eastman
Sponsor: Geoffrey Greene, Nutrition and Dietetics
A topic of interest that is growing in the general population is the idea of being sustainable, or âgreenâ, and there is a rising awareness in sustainable practices involving food and the environment. Some of the âgreenâ eating behaviors identified through my research included eating a plant-based (i.e. vegetarian or semi-vegetarian) diet, eating locally grown foods, eating organically grown foods, and eating foods that are labeled fair-trade. Frequently, these âgreenâ eating behaviors are healthful eating behaviors because they promote increased consumption of fruits and vegetables. The basis of this study was that a âgreenâ eating intervention could promote a more sustainable diet as well as a healthier one. Since college students may sometimes find it difficult to adhere to many of these âgreenâ behaviors, I incorporated many URI and campus meal plan-specific suggestions within the learning modules and messages. I tried to make learning about sustainable eating fun and applicable to URI college students using SAKAI as the intervention platform.
Currently, there are no known nutrition interventions promoting healthful eating through âgreenâ practices. This project was a yearlong pilot study which aimed to develop four educational modules and a series of motivational messages to help promote sustainable eating behaviors in college students. This study was a randomized controlled trial which tested the effects of a multimedia-based intervention on behavior change, self-efficacy, and decisional balance of âgreen eatingâ habits.
Web-based, stage-tailored interventions have shown to be effective in changing many health-related behaviors including dietary behaviors. The interventions were designed applying the Transtheoretical Model of Behavior Change (Stages of Change, Decisional Balance, and Self-Efficacy) and the Social Cognitive Theory (Goal Setting and Vicarious Learning) to promote the four topics I chose, including: an introduction to green eating, eating with ethics, eating locally, and eating a plant-based diet. The information extracted from this study will be used to construct a stand-alone web-based intervention to use in future interventions.
Keywords: Sustainability, green, nutrition, education, stages of change, Transtheoretical Mode
Soil erosion in Iowa
Soil erosion is the carrying away of soil thru the free movement of water over the surface of the land. If all the rain falling on the soil were absorbed, erosion could not occur. But the precipitation is sometimes so rapid and so great and such a small portion is taken up by the soil, that many cultivated fields are subject to extensive losses by the washing action of water. Bare bluffs and hillsides are particularly in danger of erosion and gullies formed in such locations may extend for miles and render large areas partially or wholly unfit for cultivation.
Loess soils are apt to be injured by erosion when the topography is hilly or rough and it is these soils which are affected to the greatest extent in Iowa. Large acreages in the Missouri loess, the Mississippi loess and the Southern Iowa loess soil areas are frequently rendered untillable or even entirely useless because of excessive erosion. The adoption of proper methods of preventing or controlling the washing away of valuable land is therefore important
Quantum Mechanics and the Third Law of Thermodynamics
Rodebush has recently discussed certain points concerning the third law of thermodynamics in terms of quantum mechanics. His recognition of the significance of quantum mechanics in considering the behavior of solutions and glasses at low temperatures we believe to be of interest, and we agree with the more important of his conclusions. However, there have arisen some questions of interpretation in which we differ from the statements of his paper. We have thought it of value to present here, as explicitly as possible and at the risk of some duplication of ideas, an outline of these points and a discussion of their bearing on the expected behavior of the systems under treatment. It is our opinion that the views presented below have been in the main accepted by investigators interested in the theory of the third law; however, so far we are aware no equivalent discussion has been published
I Love You Like A Yankee Loves The Red White and Blue
https://digitalcommons.library.umaine.edu/mmb-vp/1678/thumbnail.jp
NMR analysis of tâbutylâcatalyzed deuterium exchange at unactivated arene localities
Regioselective labelling of arene rings via electrophilic exchange is often dictated by the electronic environment caused by substituents present on the aromatic system. Previously, we observed the presence of a tâbutyl group, either covalently bond or added as an external reagent, could impart deuterium exchange to the unactivated, C1âposition of estrone. Here, we provide nuclear magnetic resonance analysis of this exchange in a solvent system composed of 50:50 trifluoroacetic acid and D2O with either 2âtâbutylestrone or estrone in the presence of tâbutyl alcohol has shed insights into the mechanism of this tâbutylâcatalyzed exchange. Fast exchange of the tâbutyl group concurrent with the gradual reduction of the H1 proton signal in both systems suggest a mechanism involving ipso attack of the tâbutyl position by deuterium. The reversible addition/elimination of the tâbutyl group activates the H1 proton towards exchange by a mechanism of tâbutyl incorporation, H1 activation and exchange, followed by eventual tâbutyl elimination. Density functional calculations are consistent with the observation of fast tâbutyl exchange concurrent with slower H1 exchange. The Ïâcomplex resulting from ipso attack of deuterium at the tâbutyl carbon was 6.6 kcal/mol lower in energy than that of the Ïâcomplex resulting from deuterium attack at C1. A better understanding of the tâbutylcatalyzed exchange could help in the design of labelling recipes for other phenolic metabolites
- âŠ