5,006 research outputs found

    Drilling Problems Associated with Arctic Minerals

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    With major involvements in Alaska, the experience gained from these operations reflect the success of talented personnel in meeting the challenges of climate, equipment, logistics, perma-frost, etc. Real concern stems from present delays in the Arctic program due to financing involved as well as increasing dependency of the United States upon these reserves in today’s market and supply situation

    Geomagnetic field models incorporating physical constraints on the secular variation

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    This proposal has been concerned with methods for constructing geomagnetic field models that incorporate physical constraints on the secular variation. The principle goal that has been accomplished is the development of flexible algorithms designed to test whether the frozen flux approximation is adequate to describe the available geomagnetic data and their secular variation throughout this century. These have been applied to geomagnetic data from both the early and middle part of this century and convincingly demonstrate that there is no need to invoke violations of the frozen flux hypothesis in order to satisfy the available geomagnetic data

    Experimental transonic flutter characteristics of two 72 deg-sweep delta-wing models

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    Transonic flutter boundaries are presented for two simple, 72 deg. sweep, low-aspect-ratio wing models. One model was an aspect-ratio 0.65 delta wing; the other model was an aspect-ratio 0.54 clipped-delta wing. Flutter boundaries for the delta wing are presented for the Mach number range of 0.56 to 1.22. Flutter boundaries for the clipped-delta wing are presented for the Mach number range of 0.72 to 0.95. Selected vibration characteristics of the models are also presented

    CLASSIFICATION OF EXPLOSIVES TRANSFORMATION PRODUCTS IN PLANT TISSUE

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    Explosives contamination in surface or groundwater used for the irrigation of food crops and phytoremediation of explosives-contaminated soil or water using plant-assisted biodegradation have brought about concerns as to the fate of explosives in plants. Liquid scintillation counting, high-performance liquid chromatography, and gel permeation chromatography were utilized to characterize explosives (hexahydro-1,3,5-trinitro-1,3,5-triazine and trinitrotoluene) and their metabolites in plant tissues obtained from three separate studies. Analyzing tissues of yellow nutsedge (Cyperus esculentus), corn (Zea mays), lettuce (Lacuta sativa), tomato (Lyopersicum esculentum), radish (Raphanus sativus), and parrot feather (Myriophyllum aquaticum) from three studies where exposure to explosives at nontoxic levels (1–2 mg/L in water) occurred showed that extensive transformation of the explosive contaminant occurred, variations were noted in uptake and transformation between terrestrial and aquatic plants, the products had significantly higher polarity and water solubility than the parent compounds, and the molecular sizes of the transformation products were significantly greater than those of the parent compounds (approximately 300 times greater)

    Effect of Provider Education on Urinary Incontinence Knowledge and Assessment

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    Nearly 50% of women in the United States will experience urinary incontinence at some point during their lives. Urinary incontinence impacts multiple aspects of a woman’s life, yet remains underdiagnosed by primary care providers. The Women’s Preventative Service Initiative released a recommendation in 2018 to screen all women annually for urinary incontinence. The recommendation was in response to the lack of women who seek care for urinary incontinence. The purpose of this project was to implement education and reminders for primary care providers, in order to improve urinary incontinence knowledge and assessment of women 18 years of age or older. The project was carried out in a primary care clinic with primary care providers serving as the participants. A quasi-experimental one-group pretest-posttest design was utilized. Data from a five question pre- and posttest were compared. An independent samples t-test, using a 95% confidence interval, was used to compare the pre- and posttest. Statistical significance (p-value Results indicate primary care providers who are educated about urinary incontinence in women demonstrate improved knowledge and assessment of the prevalent problem. Early intervention can soften the economic burden, improve quality of life, and improve treatment outcomes. Implementation of a urinary incontinence education program coupled with reminders can improve primary care knowledge and clinical decisions regarding urinary incontinence in women

    The Impact of Citizen Environmental Science in the United States

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    An increasingly sophisticated public, rapid changes in monitoring technology, the ability to process large volumes of data, and social media are increasing the capacity for members of the public and advocacy groups to gather, interpret, and exchange environmental data. This development has the potential to alter the government-centric approach to environmental governance; however, citizen science has had a mixed record in influencing government decisions and actions. This Article reviews the rapid changes that are going on in the field of citizen science and examines what makes citizen science initiatives impactful, as well as the barriers to greater impact. It reports on 10 case studies, and evaluates these to provide findings about the state of citizen science and recommendations on what might be done to increase its influence on environmental decisionmaking

    Performance of an Evaporative Cooling System in a Gestation House

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    This field study was conducted to determine the effectiveness of an evaporative pad cooler for modifying the environment in a gestation house in Kentucky and to compare the measured results with the calculated performance of evaporative cooling systems. The building used in the study was a 68-crate gestation house, as described in Figure 1. The building was oriented east-west and was well insulated. There were no windows in the facility. It was fully occupied, throughout the study, with sows with an average weight of 350 lbs. A negative pressure system was used to ventilate the building with a 36 single-speed exhaust fan located in the east end wall (Figure 1). A 4\u27 x 12\u27 evaporative pad was located in the west end wall adjacent to the air intake. Shutters were mounted on the outside of the building to provide shade for the pads and to protect them during inclement weather

    Carbon Dioxide Control System for a Mars Space Suit Life Support System

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    Carbon dioxide (CO2) control during Extravehicular Activities (EVAs) on Mars will be challenging. Lithium hydroxide (LiOH) canisters have impractical logistics penalties, and regenerable metal oxide (MetOx) canisters weigh too much. Cycling bed systems and permeable membranes that are regenerable in space vacuum cannot vent on Mars due to the high partial pressure of CO2 in the atmosphere. Although sweep gas regeneration is under investigation, the feasibility, logistics penalties, and failure modes associated with this technique have not been fully determined. TDA Research, Inc. is developing a durable, high-capacity regenerable adsorbent that can remove CO2 from the space suit ventilation loop. The system design allows sorbent regeneration at or above 6 torr, eliminating the potential for Martian atmosphere to leak into the regeneration bed and into the ventilation loop. Regeneration during EVA eliminates the consumable requirement related to the use of LiOH canisters and the mission duration limitations imposed by MetOx system. The concept minimizes the amount of consumable to be brought from Earth and makes the mission more affordable, while providing great operational flexibility during EVA. The feasibility of the concept has been demonstrated in a series of bench-scale experiments and a preliminary system analysis. Results indicate that sorbent regeneration can be accomplished by applying a 14 C temperature swing, while regenerating at 13 torr (well above the Martian atmospheric pressure), withstanding over 1,000 adsorption/regeneration cycles. This paper presents the latest results from these sorbent and system development efforts
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