Tunisia Renewable Energy Project systems description report

In 1979, the Agency for International Development (AID) initiated a renewable energy project with the Government of Tunisia to develop an institutional capability to plan and institute renewable energy technologies in a rural area. The specific objective of the district energy applications subproject was to demonstrate solar and wind energy systems in a rural village setting. The NASA Lewis Research Center was asked by the AID Near East Bureau to manage and implement this subproject. This report describes the project and gives detailed desciptions of the various systems

Rapid assessment of soil salinity

Non-Peer Reviewe

Experimental and Analytical Study of Rolling-Velocity Amplification during the Thrusting Process for Two 10-Inch-Diameter Spherical Rocket Motors in Free Flight

Two 10-inch-diameter spherical rocket motors have been flight tested at the NASA Wallops Station. These tests were conducted to measure "spin-up" or amplification of the spinning velocity of the motor during the thrusting process due to internal swirling of the exhaust gases. Model 1, a heavy-wall motor, experienced an increase in spin rate during thrusting of about 10 percent, whereas model 2, a flight-type motor with a lightweight motor case, experienced an increase of about 19 percent. The propellant weight and geometry were the same for both motors. A simple relationship for "spin-up" which satisfies these measured results is reported herein. Both models were spin stabilized throughout their flights. A theoretical method of predicting spin-up was derived and used to extend the measured 10-inch-motor results to spherical rocket motors of other sizes having a similar propellant geometry. This method is presented and its predictions are shown to compare favorably with the measured flight results

Should you incorporate your farm?

Caption title.Includes bibliographical references (page 11)

Proteopedia - a scientific 'wiki' bridging the rift between three-dimensional structure and function of biomacromolecules

Proteopedia is an interactive wiki-style web resource that presents 3D structural and functional information in a user-friendly manner and allows real-time community annotation

Flight Performance of a Spin-Stabilized 20-Inch-Diameter Solid-Propellant Spherical Rocket Motor

A successful flight test of a spin-stabilized 20-inch-diameter solid-propellant rocket motor having a propellant mass fraction of 0.92 has been made. The motor was fired at altitude after being boosted by a three-stage test vehicle. Analysis of the data indicates that a total impulse of 44,243 pound-second with a propellant specific impulse of approximately 185 was achieved over a total action time of about 12 seconds. These results are shown to be in excellent agreement with data from ground static firing tests of these motors. The spherical rocket motor with an 11-pound payload attained a velocity of 15,620 feet per second (m = 16.7) with an incremental velocity increase for the spherical motor stage of 12,120 feet per second

Pollutant Emissions Reporting for Ammonia Fuel Blends

This is a white paper published by SEI and is to be hosted on the SEI website and circulated among energy professionals.To combat carbon dioxide emissions, it is desirable to transition existing combustion systems to carbon-free fuels such as hydrogen and ammonia without negatively impacting air quality. However, quantitatively assessing air quality impacts of pollutants such as NOx is a nuanced process when comparing emissions across different fuels. Recently, the authors of this study published a separate paper showing that some standardized measurement approaches (i.e., measuring dried exhaust concentration) were inflating pollutant emissions by up to 40% for hydrogen combustion relative to natural gas. In this white paper, we extend this analysis to ammonia and cracked ammonia blends, showing that using concentration-based reporting approaches for comparing NOx from ammonia combustion is appropriate (less than a 3% effect), but can inflate apparent NOx emissions from fully cracked ammonia (i.e., an H2/N2 fuel blend) by 20%

Sensors and Systems for in situ Observations of Marine Carbon Dioxide System Variables

Autonomous chemical sensors are required to document the marine carbon dioxide system's evolving response to anthropogenic CO2 inputs, as well as impacts on short- and long-term carbon cycling. Observations will be required over a wide range of spatial and temporal scales, and measurements will likely need to be maintained for decades. Measurable CO2 system variables currently include total dissolved inorganic carbon (DIC), total alkalinity (AT), CO2 fugacity (fCO2), and pH, with comprehensive characterization requiring measurement of at least two variables. These four parameters are amenable to in situ analysis, but sustained deployment remains a challenge. Available methods encompass a broad range of analytical techniques, including potentiometry, spectrophotometry, conductimetry, and mass spectrometry. Instrument capabilities (precision, accuracy, endurance, reliability, etc.) are diverse and will evolve substantially over the time that the marine CO2 system undergoes dramatic changes. Different suites of measurements/parameters will be appropriate for different sampling platforms and measurement objectives

Wheat silage for dairy cattle

Wheat silage as a feed for dairy cows has become popular recently in Missouri, even though little information about nutrient content and optimum cutting stage is available. Some recent research at the University of Missouri-Columbia provides new information about wheat silage for dairy cows. This new information includes the changes in energy, protein, and minerals with stage of maturity at harvest and recommendations for cutting and storage. In general, most of this information probably applies to other small grain silages, such as oats and barley, for which similar information is scarce.R. L. Belyea, R. E. Ricketts , F. A. Martz, R.R. Ruehlow, and R. C. Bennett (Department of Dairy Husbandry, College of Agriculture)New 11/78/8