The Soil of the farm / [by J. B. Lawes ... et al.].

Abstract

The Loss of Nitrogen 99-107 (4) 1) J THE SOIL OF THE FARM. CHAPTER I. ORIGIN AND FORMATION OF SOILS. Soil and Subsoil-Conversion of Rock into Soil-Processes of Weathering and Denudation-Alluvium-Boulder Clay-Vegetable Mould-Peat. Soil and Subsoil.-The soil is that part of the ground which can be tilled and in which plants grow. It is merely the upper stratum of decayed rock mixed with A^ege table and animal remains. It varies in depth from less than three inches to more than a foot. Immediately below the soil is the subsoil, which rests upon underlying rock. The subsoil is generally more compact than the soil, being less stirred in cultivation; and it is frequently of a different color. The principal difference, however, between the two consists in the greater amount of the organic matter in the latter, which is generally present to some extent in both. The main distinction between the soil, the subsoil, and the underlying rock consists in this, that soil is rotted subsoil and subsoil is rotting rock. A vertical section of the soil will generally show several gradations. The whole may be made up of five different layers. There will be: (1) A grass layer; (2) A vegetable soil layer 5 (3) (5)

Magnetic phase diagram of the multiferroicFeTe2O5Br

“…14 The complex sequence of transitions is similar to many cycloidal and helical structures. 1,[3][4][5]26 When a magnetic field is applied, the transition temperatures shift, i.e., for B||a * , T N 1 increases and T N 2 decreases, whereas for B||c, both magnetic transition temperatures shift in parallel towards higher temperatures. In case of B||b and B > 4.5 T, the HT-ICM phase disappears along with the electric polarization otherwise present in the LT-ICM phase.…”

“…A magnetically driven ferroelectric response [1][2][3][4][5] has been almost exclusively observed in incommensurate (ICM) states with broken inversion symmetry, where non-centrosymmetric lattice distortions and ferroelectric order are induced through exchange-striction, 6-9 inverse Dzyaloshinskii-Moriya 10 or spin current 11 mechanisms. Since complex ICM magnetic orderings without inversion symmetry are often provoked by magnetic frustration, resulting from competing exchange interactions on a lattice of localized spins, low-dimensional systems with triangular geometries are considered as prominent candidates for novel magnetoelectric materials.…”

Probing the Local Coordination Environment for Transition Metal Dopants in Zinc Oxide Nanowires

“…[3][4][5] Even in systems that appear to be quite pure, reported magnetic behavior can vary widely, ranging from room-temperature ferromagnetism 6 to no magnetic ordering at all. 7,8 This variance in magnetism is attributed to the multitude of synthetic methods used for the production of DMS materials, which can result in differences in dopant environment, structural disorder, or carrier concentration. Therefore, to extract the most accurate information from any magnetic data on a DMS material, it is vital to perform a rigorous structural characterization.…”

Phase diagram of the Dzyaloshinskii-Moriya helimagnet Ba2CuGe2O7in canted magnetic fields

“…Theory shows a particularly strong coupling of ferroelectric and ferromagnetic properties in such materials [6,7]. Spiral magnetic structures are hence speculated to host multiferroicity in numerous different compounds including hexagonal Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 [8], perovskite TbMnO 3 [9] and the kagomé lattice Ni 3 V 2 O 8 [10].…”