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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The effect of pH on chemical properties of soils with varying degrees of weathering intensity and on yield and chemical composition of pearl millet and alfalfa /

Naghshineh-Pour, Bijan January 1975 (has links)
No description available.
42

Role of aluminum and iron hydroxy compounds in the absorption of organic matter by montmorillonite clay.

Kadirgamathaiyah, Sinnathamby. January 1969 (has links)
No description available.
43

Some of the effects of natural gas upon the physical and chemical properties of the soil

Adams, Russell Stanley. January 1959 (has links)
Call number: LD2668 .T4 1959 A34
44

Zeolite Formation and Base Exchange Reactions in Soils

Burgess, P. S., McGeorge, W. T. 01 May 1927 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
45

The Action of Aluminum Ferrous and ferric Iron, and Manganese in Base Exchange Reactions

Magistad, O. C. 01 February 1928 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
46

Base Exchange in Orthoclase

Breazeale, J. F., Magistad, O. C. 01 August 1928 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
47

A theoretical model of component activities in magnesian calcites.

Deknatel, William Brockway. January 1991 (has links)
Calcium carbonate, calcite, and magnesium carbonate, magnesite, form a series of solid solutions with compositions ranging 0 to 50% magnesite which is dolomite the end member of the series. The calcite magnesite solid solutions are called magnesian calcites (Mg-calcites). Mg-calcites exist in nature, in soils, in marine skeletal materials, in some marine cements, etc., and their existence has been associated with the supersaturation of calcite in sea water and the soil solution of some calcareous soils. They are clearly more soluble than calcite, but their chemical properties has not been defined. This paper examines the basic chemistry of the Mg-calcites and develops a theoretical model derived from the regular solution model and based on classical equilibrium thermodynamics. This model can be used to predict solubility and explain the behavior of the Mg-calcites.
48

Effect of CO₂ on the chemical equilibrium of soil solution and ground water.

Dyer, Kenneth L. January 1967 (has links)
The equilibrium equations relating dissolved CO2 , HC03- CO3-, H+, solid phase CaC03 , exchangeable H+ and ionic strength were programmed for simultaneous solution on a 7072 IBM digital computer. This routine was combined with an eXisting program which had been successfully used to relate the equilibrium of soluble and exchangeable Ca+ + ,Mg+ + ,Na+; dissolved Cl - , S04- ' and N03-; and solid phase CaS04 •2H20. The final systems analysis model thus developed accounted for most of the dissolved substances normally present in significant quantities in ground waters and soil solutions. This model made possible calculation of the equilibrium concentrations which would result if the concentration of one or more of these constituents were to be arbitrarily changed. This systems analysis model was used to predict the equilibrium concentrations of ionic species in soil solutions obtained from soils at moisture and carbon dioxide levels different from those prevailing in the original analysis. The soils used in this study were vastly different in chemical characteristics, texture, and genesis. Included were soils which were both acid and basic in reaction, calcareous and noncalcareous, gypsiferous and nongypsiferous, and both high and low in organic matter. In general, the chemical predictions obtained were of about the same level of accuracy as the experimental methods used to determine these chemical constituents. Soil cores from strata underlying an irrigated area were collected, and the 1: 1 soil-water extracts of these cores were analyzed for chemical constituents. The systems analysis model developed in this study was then used to estimate the concentrations of the chemical constituents which would have been in solution in the cores at the time they were sampled. The soil solutions calculated to be in most strata were similar to the underlying ground water, thus indicating a probable common origin for the water above and below the water table. It is believed that this systems analysis approach can, with minor modification, be used to predict changes in ground water quality as water percolates through strata of known chemical characteristics.
49

The creation of heathland and acid grassland on former arable land at Minsmere

Owen, Kathleen Mary January 1998 (has links)
No description available.
50

Effects of sodium, potassium, ammonium on dispersion of calcareous soils

Ibrahim, Ismail K January 2011 (has links)
Typescript. / Digitized by Kansas Correctional Industries

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