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The main characteristics of selected volcanic initial rocks for aggregates and heat-acid-resistant lightweight concretes on their base N Parameters Types of initial rocks for aggregates Types of heat-acid resistant concretes Tuff Pumice Tuffcrete pumice concrete 1 Average density, [kg/m3] 980….1340 393….483 1578 1118 2 Real density,[g/sm3] 2.62….2.65 2.43…2.52 - - 3 Porosity,[%] 49…63 80….84 - - 4 Fire resistance, [℃] 1180…1210 900…950 1200 850…900 5 Softening temperature, [℃] 1100…1120 850…900 1150 780…830 6 Heat resistance, the number of air thermal cycling 40 ... 800 [℃] (40...700 ℃) * >25 >25 20 20* 7 Relative linear thermal deformations at 900 (700 ℃) *,[%] -during first heat treatment - after recurrent heat treatment +0.53…+0.63 +0.48…+0,62 (-0.48…-0.84)* (+0.28…+0.036)* +1.76 +0.38 -3,.52* +0.46* 8 Relative volume deformations,[%], after heating up to temperature: - 800 ℃ (700 ℃) * - 900 ℃ (800 ℃) * +0.015 +0.24 -2.75* -7.2* -0.5 0.34 -2.34
The crushed sands of fractions 0.14 ... 5.00 mm (with a particle size of 2.5...3.0) and crushed stone fractions are used in concrete and macadam with grain sizes from 5 to 20 mm.

Table 2: Physical properties of AZ31 AZ31 physical property Value Thermal conductivity [W/mK] 76.9 Specific heat [J/kgK] 1040 Density[kg/m³] 1780 Poisson’s Ratio 0.35 Young’s Modulus [GPa] 45 Table 3: FE model parameters Parameter Value Tool temperature [°C] 20 Blank temperature [°C] 450 Forming speed [mm/s] 250 Number of elements for blank 3250 Friction coefficient 0.13 Heat transfer coefficient [J/m²sK] 46x103 Results and discussion The results of the uniaxial tensile tests at temperatures between 20°C and 450°C are shown in Fig. 5(a) for a strain rate of 1/s.
This could be due to a very fine initial grain size in the alloy.

Cold rolling is operated for the work hardening, refinement of crystal grain size, highly dimensional accuracy and improvement of surface quality.
Form the above, the manufacturing cost of Aluminum strip become high because of the number of processes.

Theoretical Foundations and Experimental Methods With increasing temperature, the number of vacancies (holes) in the sites of the crystal lattice increases continuously.
M-elements act as inhibitors of grain growth during alloy nanocrystallization [10–11].

Grain size analysis values were used to meet the particle fineness requirements for the following studies.
To determine the number of magnetite compounds in the samples, they were subjected to magnetic separation.

The addition of ATT increases the water absorption rate because ATT is a porous material and contains a large number of hydroxyl groups with relatively hydrophilic groups.
Evaluating distillers grains as bio-fillers for high-density polyethylene[J].

The results showed that the L S S S L L segregation in the radial direction was proportional to the solute Peclet number PeC, and the relative depth of the concaved interface hr, except for the great influence of the solute partition ratio k [22], where L C D RV =Pe (3) R h hr ∆ = (4) R is the inner radius of the crucible, h∆ is the depth of the concaved interface, V is the growth rate and DL is the diffusion coefficient of the solute in liquid phase
The method was first described by Capper et al [9-11], where three kinds of convections were identified i.e., spiral shearing flow, Ekman flow and Couette flow, depending on the Renolds number Re [27].
The Renold's number is given by γ ∆Ω = 2 Re R (5) where, R is the radius of the crucible, ∆Ω is the angular rate variation of the crucible rotation and γ is the kinematics viscosity of the melt.
In the process, the thermal field, solute redistribution, and forced convection interact each other and determine the crystal quality, such as the concentration homogeneities, grain sizes and the densities of different crystal defects, including point defects, dislocations and Te precipitates etc.

After much research, has selected a number of high-temperature (optimal temperature up to 65 ℃), not sensitive to the concentration of the product (in 30% of the sugar solution can still continue to break down cellobiose), many excellent PH adapt to a wide range strains.
Degradation of crop stalks is a more complex biological degradation process, involved a number of chemical and biochemical reaction process, so the chemical analysis of degradation process explanation course detection naturally became a topic which was concerned by people working on biotechnology and analysis.
Currently a small number of microbes that break down plant polymers at the same time, such as white rot fungi, this kind of bacteria can produce the amount of 20%-25% degradation.
[2] Osborne B.G: n IRS Analysis of Grain Past, Present and Future.

Two independent complex moduli are required for isotropic material, and the number of complex moduli increases with the degree of anisotropy (e.g., five complex moduli are required for transversely isotropic medium).
It is because that the attenuation coefficient caused by fluid viscosity is proportional to frequency, and the attenuation coefficient caused by scattering is proportional to crack density (crack density is defined as the product of the number density of cracks and the third power of the average crack radius) and to the fourth power of frequency.
His studies revealed that wave attenuation caused by scattering is not only related to frequency, but also proportional to crack density (crack density is defined as the product of the number density of cracks and the third power of the average crack radius) and to the third power of ratio of mean crack radius to incident wavelength.
Murphy [19-21] interpreted wave attenuation in his experiment in terms of frictional sliding at grain boundaries and crack faces.

The mechanically treated samples are characterized by a large number fraction of interfacial regions which often provide fast diffusion pathways for the ions.
In fact, in the spinel structure of Li4Ti5O12 the Ti4+ cations are randomly distributed over the 16d positions leading, according to quantum chemical calculations of the EFGs [17], to a large number of electrically different Li sites.
However, high-energy ball milling of microcrystalline Li4Ti5O12 for 2 h in a SPEX shaker mill leads to a highly defective material with a large number of interfacial regions and grain boundaries.