74,829 research outputs found
Ontogeny of the Tibial Spur in \u3ci\u3eMegamelus Davisi\u3c/i\u3e (Homoptera: Delphacidae) and its Bearing on Delphacid Classification
The forms of the nymphal tibial spur in Megamelus davisi Van Duzee, and their relation to Muir\u27s classification of delphacid subfamilies and tribes, are discussed
Notes on the Biology of \u3ci\u3eNersia Florens\u3c/i\u3e (Homoptera: Fulgoroidea: Dictyopharidae) with Descriptions of Eggs, and First, Second, and Fifth Instars
Information on food plants and laboratory rearing of Nersia florens Stal is provided, and the eggs and Ist, 2nd, and 5th instars are described
Spectral absorption coefficients of carbon, nitrogen, and oxygen atoms
Spectral absorption coefficients of carbon, nitrogen, and oxygen atoms tabulated for use in radiant energy transfer calculation
FUTURE TRANSPORTATION DEVELOPMENTS IN THE U.S./CANADA/MEXICO GRAINS-LIVESTOCK SUBSECTOR UNDER NAFTA AND WTO
International Relations/Trade,
Preliminary estimates of radiation exposures for manned interplanetary missions from anomalously large solar flare events
Preliminary estimates of radiation exposures for manned interplanetary missions resulting from anomalously large solar flare events are presented. The calculations use integral particle fluences for the February 1956, November 1960, and August 1972 events as inputs into the Langley Research Center nucleon transport code BRYNTRN. This deterministic code transports primary and secondary nucleons (protons and neutrons) through any number of layers of target material of arbitrary thickness and composition. Contributions from target nucleus fragmentation and recoil are also included. Estimates of 5 cm depth doses and dose equivalents in tissue are presented behind various thicknesses of aluminum, water, and composite aluminum/water shields for each of the three solar flare events
Solar-flare shielding with Regolith at a lunar-base site
The Langley high energy nucleon transport computer code BRYNTRN is used to predict time-integrated radiation dose levels at the lunar surface due to high proton flux from solar flares. The study addresses the shielding requirements for candidate lunar habitat configurations necessary to protect crew members from these large and unpredictable radiation fluxes. Three solar proton events have been analyzed, and variations in radiation intensity in a shield medium due to the various primary particle energy distributions are predicted. Radiation dose predictions are made for various slab thicknesses of a lunar soil model. Results are also presented in the form of dose patterns within specific habitat configurations shielded with lunar material
Midwest Technology Assistance Center for Small Public Water Systems Final Report
The Midwest Technology Assistance Center (MTAC) was established October 1, 1998 to provide assistance to small public water systems throughout the
Midwest via funding from the United States Environmental Protection Agency (USEPA) under section 1420(f) of the 1996 amendments to the Safe Drinking
Water Act. This report summarizes progress made under USEPA Grant# 832591-01 for funds received in Federal Years (FY) 05 and 06.
MTAC is a cooperative effort of the 10 states of the Midwest (congruent with USEPA regions 5 and 7), led by the Illinois State Water Survey and the
University of Illinois. The director of their Water Resources Institute (WRI) coordinates the participation of each state in MTAC. Dr. Richard Warner
(WRI director) and Kent Smothers were the principal investigators for this project. Kent Smothers serves as the managing director of the center, and is
responsible for conducting routine activities with the advice and counsel of Dr. Richard Warner.published or submitted for publicationis peer reviewe
Study of an advanced transport airplane design concept known as Flatbed
The design concept and configuration of the Flatbed transport aircraft are presented. The Flatbed configuration combines into one frame, the ability to haul cargo, virtually unrestrained by cross sectional dimensions of the fuselage. The feasibility and capability of the Flatbed is discussed in depth
Construction and Software Design for a Microcomputer Controlled pH/Ion Titrator
The construction of an automated titration device is described. The major components include an Apple II+ Microcomputer and 8-bit parallel interface. Fisher Accumet, Model 520 Digital pH/lon Meter, Gilmont Micrometer Buret of 2.5 mL capacity, Sigma stepper motor, power supply and driver to operate the buret, and a constant temperature bath of ± 0.005 °C stability. The limitations of the system are 0.001 pH/0.1 mv for the pH/ion sensing system, and 0.125 μL per step for the buret. The system as described is designed to determine equilibrium constants for metal ion-amino acid complexes. By changing the software a variety of different pH and redox titration experiments may be performed. A computer program used to operate the stepper motor driven syringe buret and record the pH from a digital pH meter is described. The program uses both Apple BASIC and assembly language. This is a closed loop operation in which the data from the pH meter is used to control the amount of reagent delivered by the buret. The results are displayed graphically as the titration proceeds. The variance of the pH readings are calculated using an assembly language subroutine and the calculations are done with zero round-off error
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