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Fe2+ Fe3+ Me2+ H+ O2, CO2 diffusion through micro-pores reaction with mineral grains on surface or within particle gas-liquid transfer solution phase solid phase gas phase Fe2+ Fe3+ Me2+ H+ O2, CO2 diffusion through micro-pores reaction with mineral grains on surface or within particle gas-liquid transfer solution phase solid phase gas phase Fig.1: Illustration of the key reaction and transport processes in bioleaching Gas-liquid mass transfer.
In its most universal form [6]: φ MeS )X1()d(αr −⋅∝ (9) where X represents the fractional conversion of the mineral, α(d) is a particle parameter incorporating size d as well as nature of the mineral grain, and φ a semi-empirical factor that describes the progression of leaching.
The stoichiometric coefficients νi,j refer to the number of moles of each species i consumed or produced in reaction j as written, with the value being positive for reaction products and negative for reagents.
While the fundamental rate processes and balances discussed so far apply to either category, there are a number of aspects to be accounted for in each specific case.
This approach has been successfully employed to model a number of heap leach scenarios in experimental columns and also crib tests [10, 11, 12].

In 2015, for example, there was an approximately 40 % increase in the number of wooden houses built [2].
Each project needs to take a number of parameters into consideration which influence both the overall lifetime and the costs of the façade maintenance throughout its use.
General material properties of façade planks from Siberian larch (Larix sibirica) [13] Material Properties Mean Value Tensile strength perpendicular to the grain 1.5 N/mm2 Tensile strength parallel to the grain 12.0 N/mm2 Shear strength 10.0 – 12.0 N/mm2 Table 3.
All the tested objects were labelled with a reference number.
However, the direction of the wood grain has to be considered as well, see results for façade planks, since the expansion in two tested direction of wood fibres is diametrically different as well as would be the size of the cladding board.

The typical grain size distributions of soils are shown in Fig. 1.
Fig. 4 shows the distributions of the blow numbers along the depth.
It is found that the blow numbers are all over 6, which indicates a high strength for the natural mixed soils.
In addition, the tip resistances in the cone penetration tests change from site to site at the same depth due to the differences in grain size distributions.
Depth / m Site 1 Site 2 Site 3 Tip Resistance / MPa Blow Numbers /N Depth / m Site 1 Site 2 Site 2 Fig.4.

Table1 The dimension and numbers of samples Processing project Planning Sanding Shaping Drilling Mortising Crosscutting Dimension：Height×width×length [mm] 19×102×910 10×102×305 19×76×305 19×102 Numbers of samples [piece] 30 30 60 Testing and Evaluation Method.
At the same time, weighted-average number was determined by process's impact on product quality, weighted-average number of planning, sanding, crosscutting and shaping was 2 and weighted-average number of mortising and drilling was 1.The test marks of per process was that the percentage of each level multiplied by the corresponding points, by which, the various machining properties were graded: excellent (4-5); good (3-4); fair (2-3); poor (1-2); very poor (0-1).
The comprehensive marks were the sum of the test marks of per process multiplied by the corresponding weighted-average number, full marks 50 points.
According to the criteria ASTM D1666-87, a hollow chisel was used to process the connected square mortise and it was as far as possible to make two edges of mortise perpendicular to the wood grain and other two edges parallel to the wood grain in processing.

This is due to the fact that the increment of carbon, chromium, molybdenum, vanadium atomic number in transition zone results in the increment of troostite and carbon contents.
A large number of stable carbides precipitates.
Layer and base metal also forms a number of special stable complexs.
Furthermore RE elements can purify the grain boundary and reduce interface energy.
By the use of original treatment process, the 5Cr2NiMoVSi steel die can only deal with the work-piece in a number of 5000 or so; after the use of RE nickel boride → pre-cool temperature quenching and tempering complex strength process, mold service life span has reached about 40,000 in terms of the number of the work-piece.

The fitting line could not follow well with the observed data in the higher oxygen partial pressure region, because the number of oxygen is higher than 3 in the higher oxygen partial pressure region (Fig.3(b)).
The diffusion profile in one section is calculated by the following equation: where, Cn(x) is the concentration of 18O at x in the section number of n [ 1≤n≤100, 5×(n-1)≤ x /nm ≤5×n ] and Cn-1 indicates the 18O concentration at the boundary of next before section (section n-1).
Dn* is the calculated diffusion coefficient of isotope oxygen at the section number of n in the LaMnO3 film, and t is the 16O/18O exchange duration time (t=300 s).
In air atmospheres, a number of authors have reported the oxidation of alloy and the formation of oxide scales.
With respect to the factor (iii), small and thin grain boundary in oxide scales can affect the diffusion of oxygen, although we could not observe the grain boundary diffusion in the oxide scales by SIMS imaging due to small grain size of oxides (grain boundary side is presumably on the order of 1 µm in width). 4.

Structure and component analysis shows that it contains TiB2 strips and grains with good heat resistance, which can intensify the strength of coating base and reduce the plastic deformation generated in part of the electrode surface by blasting right after the electrification.
Table 1 The spot welding parameters (spot welding pressure invariant F=4000N) Number Electric current, [A] Power on time,[ms] Phenomenon one 2k 10 No phenomenon two 2k 20 Small amount of black smoke run out three 2k 30 A very few sparks fly out four 2k 100 A very few sparks fly out five 3k 100 Black smoke run out six 4k 100 Ibid seven 6k 100 Ibid The test reduced welding time in order to ensure no sparks flying out at the beginning, meanwhile, welding current is slowly increased, so that the powder mixture to be smaller thermal shock.
As welding current increases and the growth of the power-on time, spot welding heat will be stronger, the number of particles begin to reduce, and the distribution in the matrix becomes uneven.

Based on the strong inhibition of SiC particles on the grain growth of the Αl2O3 matrix, a mixture powder of α-Al2O3 and SiC was used as feedstock to deposit the nanocomposite coatings by plasma spraying.
Since it uses powder as feedstock, the number of coating materials that can be sprayed by plasma spray process is almost unlimited.
The thickness of the coatings indirectly indicates the powder-used efficiency of the settings since the plasma gun passed over the samples an equal number of times for all runs.

As shown in the figures, Numbers of bainitic ferrite lathes and fraction of retained austenite films are greatly reduced with increasing holding time from 20 min up to 240 min.
Figure 3 demonstrates the change of Vickers hardness number (HV20) of TBF steel austempered at different high temperatures for 20 min and up to 240 min.
The decrease of hardness at each austempering time can be attributed to the reduced numbers of bainitic ferrite lathes due to the morphology change of bainitic ferrite (BF).
This is due to the formation of a larger amount of ferrite soft phase (see figures) upon the decomposition of retained austenite grains into ferrite and carbides.
De Cooman: Austenite stability of ultrafine-grained transformation-induced plasticity steel with Mn partitioning, S.

The value of λ is related with soil properties, such as porosity, grain size, grain shape and specific surface of soil et al, and the position of water filter locating on the probe.
U (%) U (%) lg t (s) lg t (s) Fig 1 ~lg t curves of the first dissipating Fig 2 ~lg t curves of the second dissipating process measuring by mini-transducers process measuring by mini-transducers On CPTU model test, the number of the pore pressure mini- transducers is 13#, 11#, 18#, 20#, 12# and 17#.
The number of sample is 16, and the detail of sampling style is as follow: all soil sample have been sampled by 4 layers, on each layer there are 4 soil samples; in each one layer, 2 soil samples have been sampled by horizontal sampling style which have been used to test the vertical permeability coefficient, and 2 soil samples have been sampled by vertical sampling style which have been used to test horizontal permeability coefficient.
Table 6 Computing value of permeability coefficient on indoor test number sampling direction distance from the top of groove (cm) Kv (×10-7cm/s) number sampling direction distance from the top of groove (cm) Kh (×10-7cm/s) 1-1 horizontal 30 1.43 1-3 vertical 35 2.66 1-2 horizontal 30 1.81 1-4 vertical 35 2.30 2-1 horizontal 60 2.51 2-3 vertical 67 2.46 2-2 horizontal 60 1.65 2-4 vertical 67 3.31 3-1 horizontal 100 1.85 3-3 vertical 105 2.28 3-2 horizontal 100 1.79 3-4 vertical 105 2.53 4-1 horizontal 130 1.15 4-3 vertical 135 3.40 4-2 horizontal 130 1.39 4-4 vertical 135 3.17 average value of Kv 1.70 average value of Kh 2.76 Comparisons with the computing value of two test methods.
Acknowledgement This paper is supported jointly by National Natural Science Foundation of China (the approval number is 40172090 and 50809035), and the direct fund and the open fund of Key Laboratory of Geological Hazards on Three Gorges Reservoir Area (China Three Gorges University), Ministry of Education (the approval number is 2008ZRJ06 and 2008KDZ02).