Widespread Occurrence of Pesticides in Organically Managed Agricultural Soils—the Ghost of a Conventional Agricultural Past?

Analytical Electron Microscopy of Extraterrestrial Ice Analogs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100181737 ◽

1990 ◽

Vol 48 (1) ◽

pp. 594-595

Author(s):

D.F. Blake ◽

LJ. Allamandola ◽

G. Palmer ◽

A. Pohorille

Keyword(s):

Solar System ◽

Analytical Electron Microscopy ◽

Biogenic Elements ◽

Widespread Occurrence ◽

Interstellar Ice ◽

Analytical Electron ◽

History Of ◽

Interstellar Material ◽

Astrophysical Ices ◽

Interstellar Molecular Clouds

The natural history of the biogenic elements H, C, N, O, P and S in the cosmos is of great interest because it is these elements which comprise all life. Material ejected from stars (or pre-existing in the interstellar medium) is thought to condense into diffuse bodies of gravitationally bound gas and dust called cold interstellar molecular clouds. Current theories predict that within these clouds, at temperatures of 10-100° K, gases (primarily H2O, but including CO, CO2, CH3OH, NH3, and others) condense onto submicron silicate grains to form icy grain mantles. This interstellar ice represents the earliest and most primitive association of the biogenic elements. Within these multicomponent icy mantles, pre-biotic organic compounds are formed during exposure to UV radiation. It is thought that icy planetesimals (such as comets) within our solar system contain some pristine interstellar material, including ices, and may have (during the early bombardment of the solar system, ∼4 Ga) carried this material to Earth.Despite the widespread occurrence of astrophysical ices and their importance to pre-biotic organic evolution, few experimental data exist which address the relevant phase equilibria and possible structural states. A knowledge of the petrology of astrophysical ice analogs will allow scientists to more confidently interpret astronomical IR observations. Furthermore, the development and refinement of procedures for analyzing ices and other materials at cryogenic temperatures is critical to the study of materials returned from the proposed Rosetta comet nucleus and Mars sample return missions.

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Use of Paper-mill Wastes on Agricultural Soils: Is This a Way to Reduce Nitrate Leaching?

Acta Agriculturae Scandinavica Section B - Soil & Plant Science ◽

10.1080/09064710310003925 ◽

2003 ◽

Vol 53 (2) ◽

pp. 56-63 ◽

Cited By ~ 3

Author(s):

Holger Kirchmann ◽

Lars Bergström

Keyword(s):

Nitrate Leaching ◽

Agricultural Soils ◽

Paper Mill

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Examination of NOxand CO2production in agricultural soils

Cereal Research Communications ◽

10.1556/crc.35.2007.2.131 ◽

2007 ◽

Vol 35 (2) ◽

pp. 689-692 ◽

Cited By ~ 1

Author(s):

Krisztina Kristóf ◽

Györgyi Kampfl ◽

György Heltai ◽

Erika Nótás ◽

Abdousalam Algaidi

Keyword(s):

Agricultural Soils

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Modeling and Analysis of Effective Electromagnetic Parameters of Capillary System of Agricultural Soils Electric Conductivity. Low-Frequency Resonances in Empty Cylinders of Circular Section with Ideal Surface Conductivity Along Helices

Journal of Automation and Information Sciences ◽

10.1615/jautomatinfscien.v50.i10.60 ◽

2018 ◽

Vol 50 (10) ◽

pp. 77-83

Author(s):

Alexander A. Brovarets ◽

Yuriy V. Chovnyuk

Keyword(s):

Electric Conductivity ◽

Agricultural Soils ◽

Low Frequency ◽

Surface Conductivity ◽

Electromagnetic Parameters ◽

Circular Section ◽

Modeling And Analysis ◽

Capillary System

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Compressive response of some agricultural soils influenced by the mineralogy and moisture

International Agrophysics ◽

10.2478/v10247-012-0091-x ◽

2013 ◽

Vol 27 (3) ◽

pp. 239-246 ◽

Cited By ~ 9

Author(s):

A.E. Ajayi ◽

M.S. Dias Junior ◽

N. Curi ◽

I. Oladipo

Keyword(s):

Agricultural Soils ◽

Tropical Soils ◽

Homogeneity Test ◽

Confined Compression ◽

Moisture Retention ◽

Soil Mineralogy ◽

Undisturbed Soil ◽

Statistical Homogeneity ◽

Compressive Response ◽

Fine Clay

Abstract This study aimed to investigate the mineralogy, moisture retention, and the compressive response of two agricultural soils from South West Nigeria. Undisturbed soil cores at the A and B horizons were collected and used in chemical and hydrophysical characterization and confined compression test. X-ray diffractograms of oriented fine clay fractions were also obtained. Our results indicate the prevalence of kaolinite minerals relating to the weathering process in these tropical soils. Moisture retention by the core samples was typically low with pre-compression stress values ranging from50 to 300 kPa at both sites. Analyses of the shape of the compression curves highlight the influence of soil moisture in shifts from the bi-linear to S-shaped models. Statistical homogeneity test of the load bearing capacity parameters showed that the soil mineralogy influences the response to loading by these soils. These observations provide a physical basis for the previous classification series of the soils in the studied area. We showed that the internal strength attributes of the soil could be inferred from the mineralogical properties and stress history. This could assist in decisions on sustainable mechanization in a datapoor environment.

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