Search results

The X-ray density of samples is calculated by following equation: (2) Where, value of 8 or known as Z is the number of formula units in a unit cell for spinel ferrite, M the molecular mass of the sample, NA the Avogadro’s number and a3 volume of the cubic unit cell.
The average grain size in range 32 – 60 nm is observed to be 42.6, 45.3, 48.7 nm for concentration x of 0.0, 0.1 and 0.3, respectively.
The grain size increases linearly up to Co0.5Mg0.5Fe2O4 of x = 0.5 Mg addition.
The dimension of the particle observed to increase with increasing of Mg concentration x with average grain size in range 32 – 60 nm.

Fracture of bolts can result from metallurgical causes of material, poor design for bolts form, poor tightening procedures for nominal applied strain, temperature and number of re-tightening cycle, thermal gradient, or other factors [1].
Many experiments show that there are grains dislocations in the primary and secondary creep, cavities only occur in the tertiary creep.
Therefore, the relaxation damage mechanism is grains dislocation.
It may be not led to fracture only by grains dislocating.
A large number of creep experiments show that the failure strain at a given temperature decreases with increasing time to rupture, and specimens accumulating creep strain at higher strain rates fail at shorter times but have higher strain capabilities.

In addition to the nature of Al2O3p is hard, the hardness increased due to some theoretical factors such as residual elastic stress as well as high dislocation density due to particles reinforced, and decrease in grain size or sub grain of the matrix[11].
The sub grain of reinforced also seen become small (Fig.5b,c).
[9] Anne Z, Widyastuti and Mochamad Z, Effect of Mg on Formation of Electroless Plating on the Surface of SiC Particles Reinforced Composites, Journal of Materials Science and Engineering Volume 4, Number 12, Desember 2010 Serial Number 37, ISSN 1934-8959, pp. 12-17 [10] Daoud,A., El-Khair, M.T.

Electroforming can used a unique part to get a number of parts, get a certain number of copies form a valuable mandrel.
On the one hand, by the refining grain size to improve surface quality and microstructure; on the other hand, electroforming is combined with the other advanced manufacturing technology.
According to the electrochemical deposition theory, the improvement of cathode current density, can refine grain and improve the electroforming layer quality and depositing rate.
In the process of nickel jet electroforming, the plating rate of jet-electroforming is up to 90 times as fast as conventional nickel-electroforming, as well as it can get more compact structure and smaller grains.

The result showed that particle was fine-grained and organic content was high showing that mean grain size in the sediment of approximately 7.7 φ, organic content (LOI) offs 8.6% and organic carbon (Corg) of 2.4%.
(°C) 23.5 22.5 DO (mg/L) 6.1 5.0 pH 7.0 6.9 Water layer ORP (mV) 150 103 Mean grain size (φ) 7.7 LOI(Loss on Ignition) (%) 8.6 Sediment Organic carbon (Corg) 2.4 2.
We could see that as compared to control and sand, the number of SRB in the sediments where gypsum was added was much higher.
Especially in the case of powder-gypsum, it showed 2.43×106 cells/cm 3 which was higher in the number of SRB for more than 10 times as compared to that of control (Table 3).

Attribute Reduction Based on continuous attribute domain Zhangyi1 1Nanchang Normal University Department of Mathematics and Computer Science, Jiangxi Nanchang, 330032 Key words: Data mining; continuous attribute domain; Attribute Reduction Abstract: Discrete data attributes reduction, there are many mature methods, but for continuous data attributes reduction, general algorithm is not very good, in real life, the continuous data feature extraction and discrete data is also important, based on the number of new brain waves as analysis object, and through the continuous eeg feature extraction comparison, verify the feasibility of the proposed method.
Introduction Attribute reduction is in a large number of attributes in the collection, in classification ability unchanged, the core attribute reduction process, the attribute reduction theory is one of the key problems in Rough set theory, Rough set theory since Pawlak has been proposed, the attribute reduction theory, algorithm and application also obtained the full development, including the reduction algorithm based on positive region, the reduction algorithm based on information theory and rough set method with other data mining and machine learning algorithm combining reduction algorithm based on discernibility matrix reduction algorithm. . these reduction theory for the amount of data and change data very fruitful, but for the incremental data or data processing often have great limitations.
Call equivalence relation knowledge, said R particles generated equivalence class as the basic knowledge, and called the quotient set of domain U R - grain of division.
EEG signal is a kind of typical real number domain, based on the eeg signals as an object for data analysis, design of data reduction method is as follows: 1, according to the characteristics of the domain, set different threshold value center 2, according to the different threshold center, classified data, classified as follows: Where n said number threshold value near the center; 3, between different samples than x 4, according to the distance of the x size, select features.

Therefore it can increase the number of cell nucleation and promote grain refinement.
As sputtering time extending, the grains of film grow up.
According to the Hall-Petch theory, the film mechanical performance will decrease with the growing grains.

Experiments The nominal composition of the alloy used in this study is 0.85Si, 0.82Cu, 1.37Mg, 0.12Cr, 0.15V, 0.03Ti and 96.5Al (numbers indicate wt.%).
When the temperature is as high as 574˚C, the molten globule can be observed and some grain boundaries are widened due to the melting of eutectic phases with low melting points on the microstructures, that leads to a slight over-burnt.
At the same time, triangle boundaries appear because the eutectic phases with low melting points between some crystal grains are melted.
That is because with the homogenization going on, the concentration gardient in the grain decreases step by step, and the quantity of diffusing matter will reduce as well according to the Equation 1, the homogenization processes will slow down at last.

This can be achieved by other dislocations (work hardening, σ┴), grain boundaries (grain boundary hardening, σgb), solute atoms (solid solution hardening, σss) or precipitation particles (precipitation hardening, σp).
The average contribution of grain boundary hardening, σgb, is relatively small in the case of conventional aluminium alloys (<1 MPa) and therefore is not considered in present study.
The B-parameter is associated with the different number of activated slip planes and is temperature dependent (B = 1-10), while the C-parameter takes into account solute trapping and depends on the chemical composition of the alloy and also strain rate (C = 0.011). dann is the critical distance between dislocations for their spontaneous annihilation: dann=Gb42π(1-ν)Evf, where ν is the Poisson’s ratio (0.33 for aluminium) and Evf is the vacancy formation energy (0.69 eV for pure Al [4]).

The grain is smaller than the lead doping samples made by the same method[18].
There are some small grains, and the number of the small grains increases with the nickel doping concentration increasing, which indicates that Ni doping would block BiCuSeO bulk sintering.