Sulfofication in soils

Sulfur has long been known to be one of the essential plant food constituents. It has always been believed, however, that there was sufficient present in all soils for the optimum growth of crops. This assumption has been very largely based on Wolff\u27s analyses of the ashes of various crops which showed the presence of very small amounts of sulfur. The recent work of many investigators has demonstrated, however, that the amount of sulfur in plant materials as determined in the ash is, in most cases, entirely too low; that there is a considerable loss of sulfur in the process of igniting; and that the amount found in the ash may therefore be a very small part of that originally present in the plant tissue

Sulfofication in Soils

Sulfur has long been known to be one of the essential plant food constituents. It has always been believed, however, that there was sufficient present in all soils for optimum crop production. This assumption has been very largely based on Wolff’s analyses of the ash of various crops which showed the presence of very small amounts of sulfur. Several investigators have found a considerable loss of sulfur upon ignition of plants for ash determinations, and recently Hart and Peterson, of Wisconsin, pointed out definitely the inaccuracy of determining the total sulfur of plant tissues by examinations of the ash. They analyzed numerous feeding stuffs for total sulfur, using the Osborn method, and compared their results with the earlier analyses of Wolff. This comparison showed quite conclusively that a large proportion of the sulfur in crops is lost upon ignition. It is evident, therefore, that considerably larger amounts of sulfur are removed from soils by common farm crops than has been supposed

Branching of the Falkner-Skan solutions for λ < 0

The Falkner-Skan equation f'" + ff" + λ(1 - f'^2) = 0, f(0) = f'(0) = 0, is discussed for λ < 0. Two types of problems, one with f'(∞) = 1 and another with f'(∞) = -1, are considered. For λ = 0- a close relation between these two types is found. For λ < -1 both types of problem allow multiple solutions which may be distinguished by an integer N denoting the number of zeros of f' - 1. The numerical results indicate that the solution branches with f'(∞) = 1 and those with f'(∞) = -1 tend towards a common limit curve as N increases indefinitely. Finally a periodic solution, existing for λ < -1, is presented.

The chameleon groups of Richard J. Thompson: automorphisms and dynamics

The automorphism groups of several of Thompson's countable groups of piecewise linear homeomorphisms of the line and circle are computed and it is shown that the outer automorphism groups of these groups are relatively small. These results can be interpreted as stability results for certain structures of PL functions on the circle. Machinery is developed to relate the structures on the circle to corresponding structures on the line

Universal measurement of quantum correlations of radiation

A measurement technique is proposed which, in principle, allows one to observe the general space-time correlation properties of a quantized radiation field. Our method, called balanced homodyne correlation measurement, unifies the advantages of balanced homodyne detection with those of homodyne correlation measurements.Comment: 4 pages, 4 figures, small misprints were corrected, accepted to Phys. Rev. Let

Time-Reversal-Violating Schiff Moment of 199Hg

We calculate the Schiff moment of the nucleus 199Hg, created by pi-N-N vertices that are odd under parity (P) and time-reversal (T). Our approach, formulated in diagrammatic perturbation theory with important core-polarization diagrams summed to all orders, gives a close approximation to the expectation value of the Schiff operator in the odd-A Hartree-Fock-Bogoliubov ground state generated by a Skyrme interaction and a weak P- and T-odd pion-exchange potential. To assess the uncertainty in the results, we carry out the calculation with several Skyrme interactions (the quality of which we test by checking predictions for the isoscalar-E1 strength distribution in 208Pb) and estimate most of the important diagrams we omit.Comment: 13 pages, 7 figure

Soil Survey of Iowa, Report No. 59—Cherokee County Soils

Cherokee County is located in the northwestern part of the state, in the third tier of counties south of the Minnesota state line and in the second tier east of the South Dakota state line. It lies mainly in the Missouri loess soil area and hence the soils of the county are largely of loessial origin

Field experiments with fertilizers on some Iowa soils

Many of the experiments carried out in the field in cooperation with Iowa farmers on some of the more extensive soil types in the state have been under way for 10 or more years. The average results secured on the Carrington loam, the Clarion loam, the Carrington silt loam, the Grundy silt loam, the Grundy silty clay loam, the Tama silt loam, the Muscatine silt loam, the Clinton silt loam, the Marshall silt loam and the Waukesha silt loam are presented and discussed in this bulletin. The results secured show that crop yields may be increased on many Iowa farms by adopting better methods of management and treatment of the land. The Iowa system of soil management, which has been developed from extensive experimental work and has been tested on many farms, points the way toward securing greater crop yields per acre and keeping the land permanently productive. The fertilizing value of farm manure and green manures is well known, but the results given, in this bulletin and in other publications emphasize the importance of keeping up the supply of organic matter in soils

Soil Survey of Iowa, Report No. 38—Hardin County

Hardin county is located in central Iowa in the fourth tier of counties south of the Minnesota state line and in the sixth tier west of the Mississippi River. It lies partly in the Wisconsin drift soil area and partly in the Iowan drift and Southern Iowa loess areas. The soils of the county are therefore of glacial and loessial origin, the major portion of the area being covered by glacial soils