58 research outputs found
Theoretical calculations and analysis for n + 6
R-matrix theory is an important methodology for applications on light, medium and heavy mass nuclides nuclear reaction in the resonance energy range. Full R-matrix formalism contains the diagonal elements of the energy levels matrix and it is a rigorous theory. Because of different assumptions and approximations, many kinds of R-matrix derived methods are obtained. The new R-matrix code FDRR is presented and includes 4 kinds of R-matrix applications. It can be used for calculating integral cross sections and angular distributions of 2-bodies reactions. The cross sections and angular distributions of n+ 6Li reaction are calculated and analyzed by FDRR code. The results are in good agreement with experimental data below 20 MeV
Updated Nucleosynthesis Constraints on Unstable Relic Particles
We revisit the upper limits on the abundance of unstable massive relic
particles provided by the success of Big-Bang Nucleosynthesis calculations. We
use the cosmic microwave background data to constrain the baryon-to-photon
ratio, and incorporate an extensively updated compilation of cross sections
into a new calculation of the network of reactions induced by electromagnetic
showers that create and destroy the light elements deuterium, he3, he4, li6 and
li7. We derive analytic approximations that complement and check the full
numerical calculations. Considerations of the abundances of he4 and li6 exclude
exceptional regions of parameter space that would otherwise have been permitted
by deuterium alone. We illustrate our results by applying them to massive
gravitinos. If they weigh ~100 GeV, their primordial abundance should have been
below about 10^{-13} of the total entropy. This would imply an upper limit on
the reheating temperature of a few times 10^7 GeV, which could be a potential
difficulty for some models of inflation. We discuss possible ways of evading
this problem.Comment: 40 pages LaTeX, 18 eps figure
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Cover Crops In Apple Orchards on Arsenic-toxic Soils
Topics include: Cover Crops Have Become Increasingly Harder to Establish in Central Washington Orchards; Lead Arsenate Spray Residues Poison Alfalfa; In Sprays, the Arsenic - Not the Lead or Fluorine - Poisons Alfalfa; The Arsenic Concentration in the Soil Affects the King of Injury to Plant Growth - Less so, the Degree; Arsenic Toxicity Is Concentrated Mainly in the Upper 4 Inches of Soil; Leagues Have a Low Arsenic Tolerance; Some Soil and Fertilizer Treatments Help Alfalfa on Toxic Orchard Soils; Applications of Some Inorganic Substances Aid Alfalfa Growth on Toxic Orchard Soils; Manure Is One of the Better Organic Substances for Alfalfa on Toxic Orchard Soils; Some Legumes Are Better Than Alfalfa for Arsenic-toxic Soils; Of the Non-Legumes, Most Grasses Are Better Than Cereals For Cover Crops in Arsenic-toxic Soils. Rye Is The Best Cereal; Summary; Literature Cite
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Report of the Fertilizer Project Data 1929-1938
Topics include: History of the Fertilizer Plots in the North Control Washington Area; List of Publications; Soil Types; Maps of Plots; Maturity of Fruit as Measured by Pressure Tests; Total Number Mature Fruits Produced per Tree and Average per Plot; Total Crop Set as Determined by Thinnings, Harvested and Ground Fruit; Total Number Thinnings and Per Cent of Total Crop Thinned; Number of Dropped Fruits and Per Cent of Matured Crop; Total Weight of Matured Fruit; Number Packed Boxes (42 lbs. not) per Tree and per Plot Matured Fruit; Number Packed Boxes (42 lbs. not) per Tree and per Plot Matured Fruit (cont.); Average Actual Size of Apples per Commercial Box of 42 lbs.; Number of Fruits and Average Per Cent IF-F-C and Culls as Determined by Color; Average Per Cent Total Red Color; Average Per Cent Total Red Color (cont.); Average Terminal Growth in Inches per Tree and per Plot; Average Circumference in Centimeters per Tree and per Plot - Also Annual Average Per Cent Increase; Per Cent Breakdown in Storage; Per Cent Breakdown in Storage (cont.); Per Cent Scald in Storage; Per Cent Jonathan Spot in Storag
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Report of the Tree Fruit Branch Experiment Station; Volume 12, No. 1
Topics include agreements, apples, apricot production and sales, Bartlett pear production, Bing cherry, blister mites, budget, codling moth data, fire danger rating record, insects and the transmission of stone fruit viruses, mildew, mite block, moths, peach sales and production, spray application, fertilizers, arsenic, toxic soil, tree removal, tree spacing, and weather data
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Report of the Tree Fruit Branch Experiment Station: Horticultural Investigations
Topics include: Tree Fruit Branch Experiment Station - 1940; Visitors; Projects:; Committee Reports:; W.P.A. Improvement Project; The National Youth Administration Project; Field Location of Experimental Programs; U.S.D.A. Variety Project; General Orchard Information:; Winter Injury Project; 1940 Pollination Studies; Dormant Spray Project:; Codling Moth Trap Records; Laboratory Experiments with Codling Moth; General Spray Experimental Work:; Regular Experimental Codling Moth Spray Program:; Spray Coverage Experiments:; Letters Referring to Spray Materials and Coverages:; Spray Residue:; Pear Psylla Survey; Pacific Mite:; Maturity Project; Spray and Physiological Injury Studies:; Orchard Cover Crop Experiments:; Fertilizer and Cover Crop Experiments:; Grade of Fruit and Value of Crop as Affected by Spray Programs; Economics of the Program at the Tree Fruit Branch Experiment Station:; Fruit Sales:; Financial Statement, April 1, 1940 to April 1, 1941; Publications
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Physical and Chemical Characteristics of Maturing Apples as Related To Time of Harvest
Topics include: Summary; Introduction; Definitions of Quality; Source of Apples; Methods and Records; The Ripening Process on the Trees; The Ripening Process in Storage; Development of Formulae to Show Comparative Value of Apples; Loss from Dropping as Related to Time of Harvesting; Acknowledgements; Literature Cite
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