Effect of temperature and initial state on variation of thermal parameters of fine compacted soils

The thermal structure of subduction zones plays an important role in the seismicity that occurs there with e.g., the downdip limit of the seismogenic zone associated with particular isotherms (350 &#176;C - 450 &#176;C) and intermediate-depth seismicity linked to dehydration reactions that occur at specific temperatures and pressures. Therefore, accurate thermal models of subduction zones that include the complexities found in laboratory studies are necessary. One of the often-ignored effects in models is the temperature-dependence of the thermal parameters such as the thermal conductivity, heat capacity, and density.&#160;Here, we build upon the model setup presented by Van Keken et al., 2008 by including temperature-dependent thermal parameters to an otherwise clearly constrained, simple model setup of a subducting plate. We consider a fixed kinematic slab dipping at 45&#176; and a stationary overriding plate with a dynamic mantle wedge. Such a simple setup allows us to isolate the effect of temperature-dependent thermal parameters. We add a more complex plate cooling model for the oceanic plate for consistency with the thermal parameters.&#160;We test the effect of temperature-dependent thermal parameters on models with different rheologies, such as an isoviscous wedge, diffusion and dislocation creep. We find that slab temperatures can change by up to 65 &#176;C which affects the location of isotherm depths. The downdip limit of the seismogenic zone defined by e.g., the 350 &#176;C isotherm shifts by approximately 4 km, thereby increasing the maximum possible rupture area of the seismogenic zone. Similarly, the 600 &#176;C isotherm is shifted approximately 30 km deeper, affecting the depth at which dehydration reactions and hence intermediate-depth seismicity occurs. Our results therefore show that temperature-dependent thermal parameters in thermal models of subduction zones cannot be ignored when studying subduction-related seismicity.&#160;

Download Full-text

Changes in selected wine physical properties during the short-time storage

Research in Agricultural Engineering ◽

10.17221/7/2015-rae ◽

2016 ◽

Vol 62 (No. 3) ◽

pp. 147-153 ◽

Cited By ~ 2

Author(s):

P. Hlaváč ◽

M. Božiková ◽

Z. Hlaváčová ◽

K. Kardjilova

Keyword(s):

Physical Properties ◽

Storage Temperature ◽

Thermal Parameters ◽

Effect Of Temperature ◽

Short Term ◽

Electric Parameter ◽

Short Term Storage ◽

Temperature Manipulation ◽

Dynamic And Kinematic Viscosity ◽

Term Storage

This article is focused on the effect of temperature and short-term storage on the physical properties of wine made in Slovakia. All measurements were performed during temperature manipulation in the temperature interval approximately from 0°C to 30°C. Two series of rheologic and thermal parameters measurements and one of electric parameter were done. First measurement was done at the beginning of storage and then the same sample was measured after a short storage. Temperature relations of rheologic parameters and electric conductivity were characterized by exponential functions, which is in good agreement with the Arrhenius equation. In case of thermal parameters linear relations were obtained. The graphical dependency of wine density on temperature was described by decreasing polynomial function. The temperature dependencies of dynamic and kinematic viscosity have a decreasing character. The fluidity, thermal conductivity, thermal diffusivity, and electrical conductivity increased with the temperature. It was found out that short-term storage had a small effect on measured properties but longer storage could have a more significant influence on selected properties.

Download Full-text

COMPRESSIBILITY BEHAVIOUR OF COMPACTED SOILS – HYPERBOLIC MODELLING

10.31224/osf.io/a5fty ◽

2020 ◽

Author(s):

U. Venkata Ratnam ◽

K. Nagendra Prasad

Keyword(s):

Void Ratio ◽

Model Parameters ◽

Initial State ◽

Compacted Soils ◽

One Dimensional ◽

Initial Void Ratio ◽

Two Samples ◽

Earth Structures ◽

Hyperbolic Behavior ◽

Engineering Projects

Compacted soils constitute most engineering projects such as earth dams,embankments, pavements, and engineered slopes because of their high shear strengthand low compressibility. The compressibility behavior of compacted soils is a key soilparameter in the design of earth structures but it is not determined correctly owing topartly saturated state. The compressibility of compacted soils can be better evaluatedunder the framework of hyperbolic behavior. One dimensional Consolidation tests oncompacted specimens were conducted using conventional oedometer apparatus underconstant water content condition. Tests were conducted by compact the soil specimensat respective optimum moisture contents for eight different soil samples, of varyinggrain size characteristics and consistency limits, collected from Tirupati Region. Themain objective of this study is to examine the compressibility behavior of compactedsoils to propose a phenomenological model. It is observed that the compressibilitybehavior can be captured by hyperbolic modeling with model parameters involved inthe behavior being initial void ratio, e0, representing the initial state of soil and otherhyperbolic constants linked to this state. The data of 6 samples were used fordeveloping the model and the data of remaining two samples were used for predictingthe observed response from the model proposed. The data of published literature hasalso been used to predict the experimental behavior to bring out the merits of themodel proposed.

Download Full-text

Effect of Temperature Change on Geometric Structure of Isolated Mixing Regions in Stirred Vessel

International Journal of Chemical Engineering ◽

10.1155/2012/287051 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Nor Hanizah Shahirudin ◽

Alatengtuya ◽

Norihisa Kumagai ◽

Takafumi Horie ◽

Naoto Ohmura

Keyword(s):

Temperature Change ◽

Geometric Structure ◽

Three Dimensional ◽

Effect Of Temperature ◽

Working Fluid ◽

Initial State ◽

Steady Temperature ◽

Single Filament ◽

Stirred Vessel ◽

Rushton Turbine

The present work experimentally investigated the effect of temperature change on the geometric structure of isolated mixing regions (IMRs) in a stirred vessel by the decolorization of fluorescent green dye by acid-base neutralization. A four-bladed Rushton turbine was installed in an unbaffled stirred vessel filled with glycerin as a working fluid. The temperature of working fluid was changed in a stepwise manner from 30°C to a certain fixed value by changing the temperature of the water jacket that the vessel was equipped with. The step temperature change can dramatically reduce the elimination time of IMRs, as compared with a steady temperature operation. During the transient process from an initial state to disappearance of IMR, the IMR showed interesting three-dimensional geometrical changes, that are, simple torus with single filament, simple torus without filaments, a combination of crescent shape and circular tori, and doubly entangled torus.

Download Full-text

Effect of temperature and the initial state on the spalling fracture of alloy 36NKhTYu

Strength of Materials ◽

10.1007/bf02330864 ◽

1996 ◽

Vol 28 (5) ◽

pp. 412-414 ◽

Cited By ~ 1

Author(s):

V. K. Golubev ◽

Yu. S. Sobolev ◽

N. A. Yukina

Keyword(s):

Effect Of Temperature ◽

Initial State ◽

Spalling Fracture ◽

Alloy 36Nkhtyu

Download Full-text

Nucleation of Disorder in Fe3Al Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061574 ◽

1967 ◽

Vol 25 ◽

pp. 312-313

Author(s):

P. R. Swann ◽

W. R. Duff ◽

R. M. Fisher

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Annealing Temperature ◽

Antiphase Domain ◽

Effect Of Temperature ◽

Domain Structures ◽

Transmission Electron ◽

Domain Boundaries ◽

Higher Temperature ◽

The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

Download Full-text

Tensile Failure of 55-Nitinol Wire

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113858 ◽

1975 ◽

Vol 33 ◽

pp. 46-47

Author(s):

F. I. Grace

Keyword(s):

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Stoichiometric Composition ◽

Tensile Failure ◽

Initial State ◽

Initial Shape ◽

Nitinol Wire ◽

Cscl Type ◽

Shear Transformation

An interest in NiTi alloys with near stoichiometric composition (55 NiTi) has intensified since they were found to exhibit a unique mechanical shape memory effect at the Naval Ordnance Laboratory some twelve years ago (thus refered to as NITINOL alloys). Since then, the microstructural mechanisms associated with the shape memory effect have been investigated and several interesting engineering applications have appeared.The shape memory effect implies that the alloy deformed from an initial shape will spontaneously return to that initial state upon heating. This behavior is reported to be related to a diffusionless shear transformation which takes place between similar but slightly different CsCl type structures.

Download Full-text

The effect of temperature on high-resolution TEM image contrast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139573 ◽

1995 ◽

Vol 53 ◽

pp. 640-641

Author(s):

T. Geipel ◽

W. Mader ◽

P. Pirouz

Keyword(s):

Form Factor ◽

Inelastic Scattering ◽

Accurate Method ◽

Waller Factor ◽

Effect Of Temperature ◽

Specimen Thickness ◽

Influence Of Temperature ◽

Debye Waller Factor ◽

Influence Of Temperature On ◽

Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

Download Full-text