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Introduction Magnetic nanoparticles are attracting a great deal of interest from both fundamental and applied points of view.[1-2] Magnetic recording media, catalysis, ferrofluids, pigments, hyperthermia, medical diagnostics, and drug delivery are among the increasing number of applications of magnetic nanoparticles.
This energy is composed of energy density of magnetocrystalline anisotropy of cubic symmetry crystal EA, energy density of magnetostatic interaction Em, energy density of grain in the field of mechanic stresses Eσ, Energy density of inter-phase exchange interaction Eex and energy density of magnetic moment of grain in external magnetic field EH.
Reference number is Government Order-2013/287, code 2.8649.2013.

In comparison with the fine equiaxed crystals zone, the columnar zone has a smaller number of crystals that means only those that had by chance a propitious growth orientation from the beginning.
As a result of these processes, the crystals favourable orientated are bigger and have a larger number of faces, which encourage them further, in the growth process.
The mechanical properties are better along the main axis of columnar crystals, because of the reduced grain boundaries, which are weak zones from the mechanical resistance point of view.
The crystalline structure of metals and alloys is determined by three important factors: - the chemical composition, which determines the primary structure in the case of mono-phasic alloys or with eutectic grains or combinations of both of them; - thermal conditions, which are expressed by the temperature distribution and the cooling rate of castings, depended on the initial temperature of liquid alloy and mould, as well as their thermal properties; - nucleation and growth from liquid conditions, expressed by the homogeneous and heterogeneous conditions, which depend on the presence of solid particles existent or especially introduced into the liquid alloy.

There are a large number of joints exist in deep orebody such as flow banding, interbed, fracture, bedding, etc, and the orientation of these joints is closely related to the extension direction of ore-lode.
Rock types include explosion breccias, quartz syenite, biotite syenite, medium and fine-grained monzogranite and plagioamphibolite.
Through the borehole wall image based on borehole camera technology and rock core image, main rock color of borehole ZK61 is gray white while the main types of rock consist of quartz syenite, biotite syenite, medium and fine-grained monzogranite and plagioamphibolite.
Due to the large number of joints and great differences in genetic type, formation period and distribution region, Advisable statistical method is used in this research for the statistics of joints.

The scanning path was discretized as Fig. 2b: a) Plasma arc moved with the jump distance dz, and the jump number was Ni along Z-axis. b) Plasma arc swung vertical to the heating line (weaving frequency f) with the jump distance and the jump number dx and Nj along X-axis, respectively.
From Fig. 8a, it can be seen that there was material partial melting near to the heating line with larger grains and significant material accumulation on the surface of metal sheet.
While Fig. 8b indicates that there was no grain growth in the heat affected zone with MDPA, and the material accumulation on the surface was not obvious.

Studies have shown that nano materials exhibit increasing number of applications such as in functional composites, microelectronics, semiconductors, catalysis, sensors and cosmetics as well as in medical applications.
All diffraction peaks are in good agreement with the JCPDS file number 7-239 for a typical hexagonal structure magnesium hydroxide.
The significant peak broadening indicates the Mg(OH)2 has a very small grain size.
The wider diffraction peak , the smaller grain size.

Because of the ore of fine-grained dissemination, in the -0.01mm grade, hematite accounted for 36%, -0.02mm accounted for 54.6%, and the gangue minerals quartz, biotite and clay minerals is more, grinding process prone to mud, therefore, plays an important role in grinding process.
This article with citric acid as the grinding agent, with reserves of 2.3 billion a hematite in Hebei province as an example to carry out the fine grain of lean hematite grinding efficiency, combined with grinding pulp viscosity, hematite surface potential index and the characteristics of adsorption mechanism of grinding aid are studied.
(serial number: Z201301) Supported by Hebei Province Natural Science Fund project.
(serial number: E2013209308) References [1] Gao Tai, Guo Xiaofei, Yuan Zhitao, etc.

There are a number of standard European and Russian documents setting out specifications for concrete and concrete mixes and the testing methods.
The standard EN 206-1 is referred to a number of dozens of other standards, both completed ones and the ones under development.
“Heavy-weighted and fine-grained concrete.
This standard applies to heavy and fine-grained concretes, cement binders used in all areas of construction, and establishes the technical requirements for the concrete rules of acceptance and test methods.
This standard applies to concrete mixtures for the preparation of hard, fine-grained and light-weight concrete and establishes rules for sampling and methods for determining the workability, medium density, voids content, desintegration, temperature and keeping the properties of the concrete mix.

The flakes consist of a great number of the 2 – 3 μ sizes microglobules.
The predominant size of the crystal grains is approximately 20 – 40 μ.
Finally, a film of two-component composite, “cellulose+NaNO2” (sample #3), consists of large transparent jelly-like cellulose grains (their size is near 200 μ), with a great number of a smaller 3 - 5 μ inclusions (Fig, 1c).
It easy to see that the morphology and sizes of MCN grains in the “free” powder and in the composite are different.
These anions can reveal luminescence of three types: being located in the volume of the MNO2 (M = Na, K, Cs) micro-crystals; being located near the surface of mentioned powder grains, and being “isolated” in the cellulose host.

This includes phase / phases present, interfaces with non-metallic inclusions, grain boundaries, grain shapes and dislocations [10-13].
The permeability or permeation rate (mol H m-1s-1) is defined by The apparent diffusivity (Dapp) was calculated by the break-through method, where, n = number of electrons transferred, Jss (mol m-2s-1) = atomic hydrogen permeation flux at steady state, F (C/mol) = Faraday’s constant, L (cm) = thickness of steel membrane, tb = the break-trough time.
SEM image shows that the steel contained ferrite, banitic ferrite phases with martensite constituents at the grain boundary.
Thus, the inferences drawn from this study are as follows. 1) The potentiodynamic study shows that anodic current density increases with the polarization potential in NACE and NS4 solutions and no passive film is formed in the anodic dissolution process. 2) The corrosion current density (Icorr) and corrosion rate of pipeline steel in NACE solution is very high compared to the near natural soil (NS4) solution. 3) The microstructure of pipeline steel consists of ferrite and bainitic ferrite phases with martensite constituents at the grain boundaries. 4) The hydrogen diffusivity in X70 pipeline steel at room temperature is 2.039 X 10-11 m2/s. 5) The hydrogen permeation study shows that the hydrogen permeation rate increases with the square root of the charging current density. 6) The subsurface hydrogen concentration also increases with the square root of the charging current density.
Acknowledgement The first author sincerely acknowledged to the Department of Science & Technology, Government of India for financial support of this project (Grant number SR/WOS-A/ET-29/2016 (G)).

Secondly, put the tube blank with the same number of layers as the swinging hose and charge to pressurize after both ends of the tube blank kept sealed to form a number of bulging ring-type corrugation.
Its basic component of organization is austenite grain with many annealing twins, while a bit of -ferrite can be detected in local position.
When the pre-strain is 20%, nearly all of the grains have the phenomena of plastic slipping and some grain has been crushed.
Nearly 80% grains have reached plastic stage and the content of martensite increases further.