Dielectric constants of deep frozen clay soils of Longgu mine (0.1∼1GHz)

Heavy clay soils that are normally resistant to wind erosion, from study site Ostrožská Nová Ves situated in the foothills of the Bílé Karpaty Mountains, Czech Republic, were a subject of laboratory analyses. The analyses should found out the influence of overwinter processes on disruption of soil aggregates and thus reason of vulnerability to soil loss by wind. Two overwinter processes were observed – freezing and thawing, and freeze-drying of the soil. Both processes have indicated the increasing of erodible fraction in dependence of water content of analysed soils. Exposed frozen clay soils that freeze-dries during the winter in the foothills of Bílé Karpaty, leaves soils highly erodible in late winter and early spring.

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TO THE DEFINITION OF DEFORMATION CHARACTERISTICS OF SOILS IN TERMS OF SEASONAL FREEZING AND THAWING

Construction and Architecture ◽

10.12737/14964 ◽

2016 ◽

Vol 3 (2) ◽

pp. 87-89

Author(s):

Александра Мащенко ◽

Aleksandra Mashchenko

Keyword(s):

Physical Characteristics ◽

Clay Soils ◽

Deformation Characteristics ◽

Freezing And Thawing ◽

Seasonal Freezing ◽

Deformation Properties ◽

Frozen Clay ◽

Definition Of

The article presents the method of determining the deformation properties of soils thaw as well as results of the physical characteristics of frozen clay soils and silty sands. The results of the coefficient of compressibility and thawing during thawing soils are given. The article presents the methods for improvement of deformation properties of soils. Keywords: coefficient of thawing, compressibility when thawing, clay soils, silty sands, reinforcement

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Electron microscopy studies of PZT ferroelectric film capacitor structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131450 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1364-1365

Author(s):

V. Kaushik ◽

P. Maniar ◽

J. Olowolafe ◽

R. Jones ◽

A. Campbell ◽

...

Keyword(s):

Electric Fields ◽

Sol Gel ◽

Ferroelectric Material ◽

Dielectric Constants ◽

Dielectric Films ◽

Lead Zirconium Titanate ◽

Si Substrate ◽

Film Capacitor ◽

Pzt Films ◽

High Dielectric

Lead zirconium titanate films (Pb (Zr,Ti) O3 or PZT) are being considered for potential application as dielectric films in memory technology due to their high dielectric constants. PZT is a ferroelectric material which shows spontaneous polarizability, reversible under applied electric fields. We report herein some results of TEM studies on thin film capacitor structures containing PZT films with platinum-titanium electrodes.The wafers had a stacked structure consisting of PZT/Pt/Ti/SiO2/Si substrate as shown in Figure 1. Platinum acts as electrode material and titanium is used to overcome the problem of platinum adhesion to the oxide layer. The PZT (0/20/80) films were deposited using a sol-gel method and the structure was annealed at 650°C and 800°C for 30 min in an oxygen ambient. XTEM imaging was done at 200KV with the electron beam parallel to <110> zone axis of silicon.Figure 2 shows the PZT and Pt layers only, since the structure had a tendency to peel off at the Ti-Pt interface during TEM sample preparation.

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The need of electron microscopy in the study of domains and domain walls in ferroelectrics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170487 ◽

1994 ◽

Vol 52 ◽

pp. 550-551

Author(s):

Wenwu Cao

Keyword(s):

Domain Wall ◽

Domain Walls ◽

High Mobility ◽

Continuum Theory ◽

Polarization Vector ◽

Ferroelectric Materials ◽

Dielectric Constants ◽

Nonlocal Coupling ◽

Cubic Symmetry ◽

Gradient Energy

Domain structures play a key role in determining the physical properties of ferroelectric materials. The formation of these ferroelectric domains and domain walls are determined by the intrinsic nonlinearity and the nonlocal coupling of the polarization. Analogous to soliton excitations, domain walls can have high mobility when the domain wall energy is high. The domain wall can be describes by a continuum theory owning to the long range nature of the dipole-dipole interactions in ferroelectrics. The simplest form for the Landau energy is the so called ϕ model which can be used to describe a second order phase transition from a cubic prototype,where Pi (i =1, 2, 3) are the components of polarization vector, α's are the linear and nonlinear dielectric constants. In order to take into account the nonlocal coupling, a gradient energy should be included, for cubic symmetry the gradient energy is given by,

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Dielectric constants of biological objects

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0079.196304c.0617 ◽

1963 ◽

Vol 79 (4) ◽

pp. 617-639 ◽

Cited By ~ 11

Author(s):

B.I. Sedunov ◽

D.A. Frank-Kamenetskii

Keyword(s):

Dielectric Constants ◽

Biological Objects

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Energetic relationships for crushing of soil clods

Progress in Agricultural Engineering Sciences ◽

10.1556/progress.2.2006.1.3 ◽

2006 ◽

Vol 2 (1) ◽

pp. 51-72

Author(s):

István Patay ◽

Virág Sándor

Keyword(s):

Moisture Content ◽

Specific Energy ◽

Soil Moisture Content ◽

Energy Requirement ◽

Clay Content ◽

Clay Soils ◽

Rigid Support ◽

Soil Plasticity ◽

Specific Energy Requirement ◽

The Relationship

Clod crushing is a principal problem with soils of high clay content. Therefore, there is a need for determining the conditions for clod breaking and clod crushing. The objective of the work was to develop a special purpose tool for single clod breaking both by rigid support of the clod and by a single clod supported by soil and to develop a machine for clod crushing. Furthermore, the purpose was to determine the relationship between the specific energy requirement for clod crushing in the function of soil plasticity and the soil moisture content by the means of the developed tool and machine. The main result of the experiments is summarized in a 3D diagram where the specific energy requirement for soil clod crushing is given in the function of the moisture content and the plasticity index for different clay soils.

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