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Through heat treatment and tempering, the microstructure is improved, the grains are refined, and the grain boundary distance is shortened.
When the test sample is damaged or exceeds the expected number of stress cycles, the test is terminated, as shown in Figure 1.
Data exceeding the expected number of stress cycles were removed, and 2 failure data were obtained at each of the 4 stress levels where failure occurred, totaling 8 data.
Table 5 Data for the Normal Temperature Dacromet S/N Curve Test piece number Test amplitude [MPa] Constant average stress [MPa] Testing fatigue life (number of cycles) 1 44 450 >5000000 2 48 1343000 3 44 >5000000 4 48 1425000 5 44 >5000000 6 48 >5000000 Table 6 Data for the Low Temperature Dacromet S/N Curve Test piece number Test amplitude [MPa] Constant average stress [MPa] Testing fatigue life (number of cycles) 1 69 450 >5000000 2 71 1327000 3 69 >5000000 4 71 1810000 5 69 >5000000 6 71 >5000000 The horizontal data processing corresponds to a fatigue strength of 50% failure probability when the fatigue life N=5E6 is: σAN=16j=27σaj (10) 2.3.
The figure includes slopes m1 and m2, the number of cycles at the turning point of the S/N curve ND, and the stress range value ∆σ*Aunder ND.

Siloxane-nanoparticle films are then deposited (sprayed) on "Opuka", a fine-grained argillite which was used for the restoration of the castle of Prague.
For this reason, composite films are deposited on "Opuka" specimens; Opuka is a fine-grained argillite, used for the restoration of the Prague castle.
A sequence number is provided in the upper left corner of each photograph. 12 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 The effect of roughness on the wettability of a surface has been quantified by Wenzel and CassieBaxter.
c) a) 0 Number of pixels b) Scale of gray value 255 Selected pixels (φs) c) a) Number of pixels b) Scale of gray value Selected pixels (φs) c) a) 0 Number of pixels b) Scale of gray value 255 Selected pixels (φs) c) a) Number of pixels b) Scale of gray value Selected pixels (φs) qualitative data) which revealed the morphologies of the composite films.
The spraying technique was employed to treat Opuka, a fine-grained argillite which was used for the restoration of the castle of Prague.

The relative number average molecular weight of the undepolymerized PET was determined by end-group method.
The mass average molecular weight (Mw) of PET was 38905, the number average molecular weight(Mn) was 25703 and the viscosity-average molecular weight was 18197, which was calculated from the following equation respectively: 分别由公式 2-1 、 2-2 、 2-3 计算所得到：
Because the end-group number included in each macro-molecule chain is definite, therefore, in certain weight sample, the molecular weight of the polymer may be calculated via the end-group number: The curves of the molecular weight of the PET depolymerization residues with the catalysts of zinc acetate, zinc sulfate and stannous oxide versus time was shown in Fig.4, Fig.5, and Fig.6 respectively.
To compare with the molecular weight of the grain of 25703, there was a large degree of reduction.

In the case the effect of carburization on life time of heat resistant stainless steel tubes (HP type), Tari et al. [13] reported that a continuous grain boundary carbide network was formed at high temperatures.
He found that the carburization process, which leads to the precipitation of carbides (at grain boundaries) and the formation of sigma phase (within the matrix), was the main cause of mechanical failure.
Under the oxide layer, there is a carbide depleted zone in which carbides are totally absent and only a few of blocky SiO2 oxides left in the grain boundaries.
And hardness of carbide-rich zone and matrix increases along with service time extending, for the number or dimensions of carbides increasing.
The oxide layer include an external Cr2O3 layer and an internal SiO2 layer, and external oxide layer is fully covered the inner wall while internal SiO2 oxide presents dendritic growth along the grain boundary.

This microstructural parameter is dependent on both the previous austenite grain size and on the cooling rate [8].
A lower grain size limit of 4.5µm was established for the definition of a "unit", given that a minimum of 2 pixels per unit was considered for the applied step size.
The austenite mean grain size prior to transformation was in the range 27-34µm for all the conditions tested.
However, other authors have proposed that the fracture process in pearlitic steels is controlled by a structural unit made up of a number of colonies exhibiting close crystallographic orientations for ferrite, usually known as the "crystallographic ferrite unit"[19, 20].
It is expected that for a given austenite grain size, the "crystallographic ferrite unit" size will depend on the transformation temperature.

Maximum raman shift occurs at 263 cm-1 which showed the growth of the grains after sintering at 1150 °C.
The grain size of the sample also increased as we increased temperature from 750°C to 1150°C.
It has been investigated by many researchers that ferrite materials have higher Initial permeability due to bulk density and large grain size [29].
The surface morphology, density, porosity, grain size, Fe+2 content and single phase structure of the ferrite may affect the initial permeability.
FESEM results showed that yttrium iron garnet has average grain size between 60 to 110nm with better morphology at sintering temperature of 1150°C.

It allows even large castings to solidify rapidly, thereby reducing segregation and grain refinement.
Results showed that, after the formation of the air gap, IHTC first exhibited a rapid decrease, followed by an increase and then another decrease; IHTC was found to decrease as gap width increased and as the duration of gap formation increased. 1 Introduction Water-cooled casting is characterized by in fast cooling and so produces castings with reduced grain refinement and segregation.
Due to a number of factors, including process, material and state of the heat transfer interface, there is no accurate theoretical solution to heat transfer coefficient with an air gap.
Researchers have conducted a large number of studies on this matter, establishing models and methods of calculation[2~4] and finding casting/mold IHTC solutions suitable for different casting materials, pouring temperatures[5,6], initial temperatures, mold materials[7,8], intended geometric shapes[9], casting pressures[10,11], mold surface coating materials and thickness[12], mold surface roughness, and air gaps[13,14].
In other words, the method of non-linear estimation used F(h) minimization as the criterion: (1) Here, Tj,i and θj,i were the computationally simulated temperature and experimentally measured temperature at measurement point j and time interval i, respectively; K1 and K2 are the total number of temperature measurement points and the total number of time intervals, respectively; h is IHTC. 4 Simulation Results and Discussion 4.1 Results of Temperature Measurement Experiments The following discussion first provided the measured temperature curves.

The quality assurance department plans to optimize the process in order to reduce the number of defects.
The quality assurance department plans to optimize the process in order to reduce the number of defects.
Upon further analysis, it was found that the attempts to perform automatic counting were impracticable and uneconomic due to the low number of experiments planned during the optimization process.
It was considered that an interaction between the observer and the particular PCB might occur, which means that an appropriate model for such a situation is as follows: Yij,r = m + ai + dj + (ad)ij + eij,r (1) where: i – PCB identification label, j – identification label of a human observer counting droplets, r – replications, m – mean of droplets counted from all considered PCBs, ai – droplets count for i-th PCB, dj – systematic counting deviation assigned to j-th human observer (constant tendency to return lower or greater count), (ad)ij – systematic deviation of j-th observer couting droplets from i-th PCB, eij,r – random error of j-th observer couting i-th PCB in r-th replication, Yij,r – number of droplets counted by j-th observer from i-th PCB in r-th replication.
Sozanska, A Comparison of Grain Quantitative Evaluation Performed with Standard Method of Imaging with Light Microscopy and EBSD Analysis, Prakt Metallogr-Pr M 46 (2009) (9) 454-468

This process, valuable for a great number of composite powders, is of great simplicity and has a relative low synthetic temperature of powders.
The sample number and corresponding process are shown in Table 1.
Table 1 SrTiO3 Sample Number and Corresponding Process Sample Number Temperature (°C) Soaking time(h) Materials Process A1 800 2 Strontium carbonate, Titania Gel solid state reaction A2 900 2 A3 1000 2 A4 1100 2 Fig.2.
No agglomerate or big grain shows.

The bio-energy industry can absorb a large number of surplus rural labors, and transfer them to the departments or services before and after agricultural production sectors.
If the agricultural waste is used as bio-energy, the organic fertility of cultivated land will be reduced, and the grain yield and poultry livestock feed would be also reduced.
In China, the production of fuel ethanol by grain should be strictly controlled to develop the bio-energy, and the energy utilization of living waste should be taken seriously.
There are plenty of trees and flowers for urban greening and a large number of biomass materials.
These places also absorb a large number of wastes generated by city.