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Meanwhile photogenerated electrons and holes respectively from conduction band and valence band can also be captured by impurity energy levels and separating the electrons and holes, which lead to a decreasing of rate of their recombination, increase the lifetime of carriers and increase the number of carriers in per unit time and per unit volume.
This may be due to that when the doping amount is less than the optimum amount, with the increase of dopant concentration, the number of the doped ion trap provides increased, enhance the inhibition ability of electron/hole recombination and the photocatalytic performance improves.
The samples of 0.2% Ce and 0.5% Fe doped TiO2 sintered at 500oC for 2 h, XRD patterns show that the crystal is anatase and SEM pictures show the morphology is small grain of porous spherical structure.

Despite the large number of works devoted to the study of the properties and machining technologies of alloys Al-Mg system [3-13], obtaining longish deformed semi-finished products from these alloys is an urgent task for production.
The following data chosen as the initial data and boundary conditions for modeling: the material of the workpiece is an aluminum alloy, the material of the instrument is tool steel; billet material isotropic; the conditions of contact interaction between the workpiece and the rolls were accepted according to the Siebel law with the friction index at the metal deformation in the rolls ψr = 0.9 and on the die ψd = 0.3; friction on the contact of the rolls and the die were not taken into account; relative reduction during rolling 50 %; the initial temperature of the workpiece Tb = 400-550°C, heat exchange with the environment and the tool; the initial temperature of the die (Td) and of the rolls (Tr) varied from 100 to 200°C, and heat exchange with the environment and the workpiece takes place; the number of finite elements into which the workpiece is divided was 32 thousand pieces.
Zhang, The effect of grain boundary character evolution on the intergranular corrosion behavior of advanced Al-Mg-3wt%Zn alloy with Mg variation.

Density of spruce C22 was approximately 410.0 kg·m-3 and tensile strength parallel to the grain, which exactly was tested here, was approximately 13.0 MPa.
Adhesive system Mark (Fig. 3) Surface treatment Number of test samples [pc.]
The maximum shear strength of the adhesive system stated by each manufacturer is marked by number 0.

Particle size analysis was performed by mechanical sieving up to 80µm according to the standard XP P94-041 and by laser grain size for particles under 80µm following the standard ISO 13320.
Lifts Specimens number Fibre content (%) Lift 2 3 3.7 ± 0.2 Lift 3 3 2.1 ± 0.2 Lift 4 3 2.3 ± 0.1 Tab. 2: Fibre content measured in laboratory 3.2 Water content in cob mix and walls According to the water contents measured in three cylindrical and three prismatic specimens of three lifts, there is not a significant variation in the water content, with the range of 18.4 % to 21.9 % (Fig.10).
ρ dry (kg/m3) Sepecimens number Cylindrical Prismatic Lift 2 3 1715 ± 11 1660 ± 19 Lift 3 3 1763 ± 22 1762 ± 13 Lift 4 3 1776 ± 44 1873 ± 11 Tab. 3: Dry density of cylindrical and prismatic specimens The variation of dry density shown in Fig.12 is ranging between 1660 and 1873 kg/m3 in (3) lifts.

The total number of measured points was 21.
The total number of brick elements was 10000.
During the X-ray diffraction process, there exists large surface grains and texture orientation according to the diffraction information, which have significant influence on the measurement results.

Table 2 Grain size of modificated VO2 powder Sample D50 of after storage [μm] D50 of after ultrasonic 20min [μm] Before modification 33.410 13.586 Modified by Ethanol 29.366 11.055 Modified by Toluene 18.757 7.030 Modified by Ethyl acetate 19.994 7.815 Infrared Spectroscopic Analysis before and after Modification: Fig. 6 shows the FT-IR spectrogram of VO2 before and after modification.
Fig. 8 Ligand way of carboxylate COO and metal ion Among the three complexes, the difference between the two stretching vibration peaks of carboxylate radical COO in terms of wave number position is relatively significant; the frequency difference could be used to determine the mechanism of coordination between carboxylate radical and VO ion.
When unidentate ligand comes into being, the wave-number difference between symmetric stretching vibration peaks of COO will exceed 200cm-1.

HVOF Cr3C2-NiCr coating also showed excellent erosion-corrosion behaviour, high compactness, fine grain size structure and homogeneous distribution[6].
The Addition of CrC(20NiCr) as reinforced material in metal matrix was employed with high velocity oxigen fuel (HVOF) systems with the constant parameter in order to increase the coating capability on thermal shock resistance without decrease significantly their original characteristic on hardness number.
MMC with 140 mesh of NiCr particle size is the most heavily unmelted particles and spread, while MMC with 270 mesh of NiCr particles size, the number of splats which is dominated by Cr and Ni element than unmelted particles.

The TCP sample displays all main peaks that is in agreement with one of XRD pattern reference for β-TCP according to ICDD PDF Number 00-009-0169.
On the other hand, when chitosan was included in the precipitation process (TCP-K), the secondary phase of calcium pyrophosphate (CPP) appeared at 2θ angle of 32,102, according to XRD pattern reference for CCP with ICDD PDF Number 00-020-0024.
Pure β-TCP powder has a typical morphology of nanoscale single particles but mostly agglomerated grains [10, 12].

In case of a deformation occurring in the α+β-region, the softening processes are defined not only by the strength of the α- and β-phases, but also by their number, as well as the potential of each phase for plastic deformation, the ease of sliding transmission at the interphase and intergrain boundaries, the aspects of the development of dynamic hardening and softening processes in two-phase structures.
The high strength of these alloys may be due to both solution hardening and microstructural hardening, since alloys with an approximately equal number of phases have a smaller grain size [1].

In literature a number of research works related to precision, surface finish and surface integrity in WEDM can be found.
After this contribution, a large number of works have been published on topics such as on-line monitoring of current and voltage [13] and the on-line classification of discharge types [14] amongst others.
Two types of hard metal have been studied (both 11-12% in Co, common in the tooling industry), but with different grain sizes: the first one with an average size of 3.7mm and hardness 1240HV30 (±2%); the second one with average particle size 0.3mmand hardness 1600HV30 (±2%).