9,596 research outputs found
A revision of Calyptochloa C.E.Hubb. (Poaceae), with two new species and a new subspecies
Thompson, E.J. & Simon, B.K. (2012). A revision of Calyptochloa C.E.Hubb. (Poaceae), with two new species and a new subspecies. Austrobaileya 8(4): 634–652. Two new species of Calyptochloa C.E.Hubb. (Calyptochloa cylindrosperma E.J.Thomps. & B.K.Simon and C. johnsoniana E.J.Thomps. & B.K.Simon) endemic to central Queensland, and a new subspecies of Calyptochloa gracillima C.E.Hubb. (C. gracillima subsp. ipsviciensis E.J.Thomps. & B.K.Simon) endemic to southeast Queensland are described and illustrated
Subsurface Irrigation Research in Arkansas
A pilot study conducted in 1963 indicated that (1) cotton yields could be increased by subirrigation, (2) drilled orifices were unsatisfactory because of internal plugging caused by burrs and drilling particles, and (3) operating pressures of 5 and 10 psi were excessive, and 5 psi probably should be considered as an upper-limit pressure. A greenhouse study of a subirrigation system indicated that 2 psi should, in general, for in-wall orifices, be considered as a lower-limit pressure when orifices are built into the pipe wall. The greenhouse study also indicated that a placement depth of 12 inches was preferable to 18 inches in terms of the amount of water required. Twelve inches was used as the depth of placement for the field subirrigation system. A device was developed for forming orifices with a hot needle. This method has advantages over the drilled orifices used in the pilot study in that the forming process does not produce loose particles to fall inside the pipe or burrs which remain attached to the inner edge of the orifice and later cause stoppage problems. This method also seems preferable to punched orifices which tend to become smaller with time due to rebound of the plastic
Report of the Fourth District Economists' Roundtable
A summary of the 1994 forecasts for real output and inflation presented by 15 members of the Fourth District Economists' Roundtable at their January 1994 meeting, highlighting the measurement of service sector prices and the role of small businesses in creating jobs.Federal Reserve District, 4th
Galactic cosmic ray exposure estimates for SAGE-3 mission in polar orbit
An analysis of the effects of galactic cosmic ray (GCR) exposures on charge-coupled devices (CCDs) was performed for the SAGE-III 5-year mission in sun-synchronous orbit between 1996 and 2001. A detailed environment model used in conjunction with a geomagnetic vertical cut-off code provides the predicted 5-year fluence of GCR ions. A computerized solid model of the spacecraft was used to define the effective shield thickness distribution around the CCD detector. The particle fluences at the detector location are calculated with the Langley heavy-ion transport code, and these fluences are used in conjunction with estimated nuclear stopping powers to evaluate dosimetric quantities related to the detector degradation. A previous study analyzing effects of trapped particle and solar flare protons indicated an approximate 20 percent reduction in detector sensitivity for the mission. The galactic cosmic ray contribution was thought to be relatively small and therefore was not previously analyzed. The present study provides quantification of the GCR effects, which are found to contribute less than 1 percent of the total environment degradation
Midyear report of the Fourth District Economists' Roundtable
A summation of the May 20, 1994 meeting of the Fourth District Economists' Roundtable, at which participants offered their views on the current and prospective state of the economy and discussed the limitations of describing the U.S. business cycle.Federal Reserve District, 4th
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