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Although all these methods require sophisticated and costly equipment as well as absolute observance of melting temperature mode specifications, they promote an increase of the number of crystallizing nuclei and grain refinement as compared to impurity modification methods whose effect depends on a uniform distribution of modifier elements in a melt, in some cases it is limited in time, and the modifying elements themselves may affect a chemical composition of an alloy.

The superconductivity of MgB2 is not sensitive to weak links, such as grain boundaries, which enables some techniques to be applied on the processing of MgB2 materials.
Transference number of charge-transfer complexes in solutions: methanol-iodine and ethanol-iodine, Proc.

One concern is the mean free path (mfp) of the molecules relatively to gap size (S) with the following relationship. 12 )2( − = nd mfp π (1) Where n is the number of molecules per unit volume, equals to p/kT, d is diameter of gas molecule (1.5x10-10 m), k is Boltzman constant (1.38x10 -23 J/atom-K).
Fig. 2 (a) SEM micrograph of 8 mol% Y-doped ZrO2 plate sintered at 1500 o C for 1 h and (b) the sintered density and grain size of the samples as a function of sintering temperature.

For thixoforming it is mandatory to reach the process temperature as quickly as possible in order to avoid unwanted grain coarsening and to keep the risk of scaling minimal.
Finally the control variable has to be represented by a crisp number.

It also has a spongy structure and exhibits multigrain agglomerations of well-crystallized grains that might be due to high surface energy of nanoparticles and dipole interactions between ferrites materials.
Acknowledgements The authors thank Universiti Teknologi PETRONAS for funding the project under the YUTP-FRG grant with cost-center number 0153AA-E18.

On the contrary, a number of small clusters containing Cu, Mg and Ag atoms are found in Fig. 7(c), (d).
This observation indicates that the microalloying element of Ag accelerates the nucleation of the precipitates near grain boundaries.

Table 1 Effects of rare earth dosage on optical properties of the samples Serial numbers of samples x(RE)/% Powder colors Afterglow colors λEX/nm λEM/nm Eu2+ Dy3+ L -1 2 3 Light yellowish green yellowish green 364 510 L -2 3 3 yellowish green yellowish green 365 503 L -3 4 5 yellowish green yellowish green 364 505 L -4 6 8 yellowish green yellowish green 368 512 From table 1, it can be seen that the rare earth dosage affects not obviously to the afterglow colors of phosphorescence materials.
When the temperature rising to 1400˚C, the sintered powder colors are non-uniform, the surface colors of samples are mainly yellowish green and some red grains disperse among them, the luminescent intensity observed by eyes is stronger, but the extra sintering often occurs resulting in the samples being taken difficultly because of bonding on the pot and it is difficult for the powder to grind on because of its great rigidity so that its luminescent intensity decreases obviously.

Table 1 Crystallinity and crystalline grain size of Jade fiber and polyester fibersand crystallite dimension of Jade fiber and polyester fiber Sample Name Crystallinity /% d / A Polyester 40.87 3.9662 Jade fiber 18.64 4.5127 2.3 Moisture absorption of the jade fiber TThe natural moisture regains of the jade fiber and polyester fiber are shown in Table 2.
Table 2 Natural Regain of jade fiber and polyester fiber (25 °C, R.H.40%) Sample number Jade fiber G 0 / g W∕% Polyester G 0 / g W∕% 1 49.72 0.5632 35.69 0.4011 2 49.73 0.5429 35.62 0.4038 3 49.74 0.5227 35.45 0.4103 Table 2 shows that under the condition of temperature 25 °C, relative humidity 40%, the average natural moisture regain of the jade fiber was 0.5429% while that of polyester fiber was 0.4051%.

Compared with other formulations, acid sulphate copper plating baths provide a number of desirable features, including the lower cost, fast deposition rate, ease in maintenance, lower toxicity, and good uniformity in strength and ductility [4].
It is noteworthy that the electroplating of copper with or without sodium citrate followed Scharitker−Hill 3D instantaneous nucleating and subsequent grain growth mechanism which is controlled by diffusion of copper ions.

It is expected that the presence of a large number of UNCD crystallites in the films sharpens the sp3 peak because the wave function around the Fermi level in crystallites must be uniform rather than that in the amorphous structure.
We believe that the grain boundaries terminated by hydrogen atoms are responsible for the large sp 3-CH peak [14, 15].