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The aged specimen picture is characterized by a greater darkness that can be related to a greater size of precipitates, which migrate towards grain boundaries and grow into bigger coherent structures.
On the contrary, fatigue testing results are highly dispersed over the S-N diagram and the limited number of data available do not allow to establish a correlation between thermal ageing and fatigue limit of the alloy.
Another relevant effect induced by thermal ageing is the segregation of precipitates towards the critical zones of the microstructure, such as grain boundaries, that can produce a drastic reduction in the mechanical strength.

Boyce [6-7] and Sanderson et al. [2] performed drying tests in small beds of grain under uniform airflow that the location of the drying front by measuring air temperatures was successfully identified.
Gu et al. [11] performed the experimental study to investigate the temperature distribution at various positions in the in-bin drying of grain.
At fixed heating power, the hot air temperature decreased as the air velocity increased this is because of the increase of the average convection heat transfer coefficient (as described by Eq.(1)) depending on the velocity of the fluid flow in term of Reynolds number (Re) [12].

The manufactured seeding stack was removed from silicon by mechanical polishing using a diamond grain size of 3 µm (= processing route II). 3C-SiC domains in combination with highly defective areas due to surface contaminations of the seed can be observed.
(a) (b) Fig. 2: (a) SEM picture of the 3C-SiC/Si interface after melting the silicon (processing route I) and (b) related morphology of an as-grown sample grown on the 3C-SiC/Si interface after mechanically polishing the seeding surface with a grain size of 3µm (processing route II).
Acknowledgment This work is funded by the European H2020 framework programme for research and innovation under grant agreement number 720827 (CHALLENGE).

Reducing the rate of cooling from high temperatures ensure the time necessary for training the austenite to the edges by the ferrtic grains.
The attack by cavitation it propagates mainly in the ferrite phase and on the limits by separation of the grains of ferrite and austenite and therefore carry a low speed cooling from high temperature favoring reducing the proportion of ferrite phase at room temperature and consequently an improvement in resistance erosion by cavitation.
Acknowledgements The support by a grant of the Romanian National Authority for Scientific Research, CNCS – UEFISCDI, project number PN-II-ID-PCE-2011-3-0837 is acknowledged.

Table 1 The compositions of the testing samples [wt%] Sample number 1# 2# 3# 4# 5# 6# Pure aluminum 100 80 60 40 20 0 Aluminum scraps 0 20 40 60 80 100 Image Analysis.
(a) 100μm (b) 100μm (c) 100μm (d) 100μm (e) 100μm (f) 100μm Fig. 1 The morphology of inclusions in pure aluminum samples (a) 1# (b) 2# (c) 3# (d) 4# (e) 5# (f) 6# Table 2 The results of image analysis of inclusions [volume percentage %] Sample number Inclusion content (%) Description 1# 0.469 No obvious inclusions and holes 2# 0.718 A little inclusions and holes 3# 1.600 Obvious inclusions and holes 4# 3.226 Obvious flocculent inclusions 5# 5.467 Abundant flocculent inclusions 6# 7.043 Abundant inclusions and holes The volume percentage of inclusions detected by image analysis can be transferred into mass percentage according to the following formula: (2) where, kρ is the density ratio of inclusions and metal matrix, kρ = 1.04 for oxide inclusion in aluminum alloy.
Fig. 2 The standard curve of alumina solution Table 3 The content of inclusion detected by colorimetric method [wt%] Sample number 1# 2# 3# 4# 5# 6# Inclusions content 0.09 0.21 0.33 0.48 0.66 0.82 Flux Rinsing Method.
No obvious inclusions and porosity can be seen after rinsing, which implies that majority of inclusions in sample are removed after flux rinsing. 100μm 100μm b a Fig. 3 Metallograph before (a) and after flux rinsing (b) Table 4 The result of inclusion content from flux method [wt%] Sample number 1# 2# 3# 4# 5# 6# Content of inclusions 0.32 0.64 0.98 1.32 1.84 2.12 The comparison of content of inclusions detected through the three methods is shown in Table 5: Table 5 Comparison of inclusion contents among the three methods [wt %] Sample number 1# 2# 3# 4# 5# 6# Image analysis 0.45 0.69 1.54 3.11 5.27 6.79 Colorimetry 0.09 0.21 0.33 0.48 0.66 0.82 Flux rinsing 0.32 0.64 0.98 1.32 1.84 2.12 It can be seen from Table 5 that the values got from image method is the highest, much higher than colorimetry and flux methods.
(1) Holes existing on grain boundary are difficult to distinguish in setting gray threshold and geometric threshold in image analysis, so they are easily mistaken for inclusions

College of Engineering and Technology, Hubli, India amb_gorwar@bvb.edu, bpp_revankar@bvb.edu, cvijay.tambrallimath@gmail.com, dsekermail10@gmail.com Keywords—Post harvest losses, solar crop drying, solar PV/T systems,drying rate Abstract—The growing population demands adequate supply of food grains for its sustenance and supporting life activities.
The agricultural produce in India has increased over the years due to improved farm practices despite of which the country is ranked 2nd in terms of the number of children suffering malnutrition.
The post harvest losses in India are estimated at 4 to 6 percent for food grains and 16 to 18 percent for fruits and vegetables occurring at various stages of harvesting, storage and processing.
The post harvest remedies for the loss of food grains and other agricultural produce includes better post harvest storage techniques based on removal of moisture to store the produce without being perished.

Table 1 Uniaxial compressive strength of ZKD high-moisture quick-concreting material Number Water cement ratio Cementation dosage /kg·m -1 Water dosage /kg·m -1 Cementation time /min Uniaxial compressive strength /MPa 2h 24h 7d 28d 1 0.8 873 698 7 14.4 19.0 21.32 22.55 2 1.0 744 744 8 10.2 15.8 17.90 19.10 3 1.2 647 776 8 8.4 14.0 15.52 16.97 4 1.5 542 813 10 4.48 9.14 10.36 11.51 5 2.0 426 850 12 3.33 6.26 7.92 8.7 6 2.25 385 866 14 2.42 4.74 6.19 7.08 7 2.5 352 880 16 2.05 3.97 5.08 5.44 Table 2 Uniaxial compressive strength of ZKD high-moisture quick-concreting material with ash [6] Number Ash variety Dosage /kg·m -1 Uniaxial compressive strength /MPa Consolidation material water ash 1d 3d 7d 28d 1 Flue ash 1 350 700 450 2.48 2.98 3.15 4.27 2 Flue ash 2 350 700 440 2.51 2.92 3.35 4.22 3 Flue ash 3 350 700 400 1.77 2.57 2.84 3.57 4 Flue ash 4 350 700 420 2.47 3.05 3.35 3.65 5 Boiling ash 1 350 700 480 2.85 3.86 4.33 4.62
Compared with Portland cement , the high-moisture quick-concreting material has a good tenacity and cohesive property. if the load increases to result in greater deformation , load is beared mainly by the rock body and soil body with higher strength , in this way , the breaking condition of the broken rock and soil bodies may transform from original strength condition of fissure surface to near strength condition of rock and soil bodies , so as to improve the mechanical performance of fissure surface . 2.2 Improvement of stress condition of rocks and soils Under action of the pumping pressure , the grout of high-moisture quick-concreting material with fine grain would compress and close some small fissures and the closed fissures which may be not filled except filling some bigger fissures .
Under effect of mining-induced abutment pressure , the support of roadway is more difficult and it is easy to cause the roof fall . 3.2 Experimental analysis of broken coal seam reinforced by grouting Three main factors and 7 schemes are studied to analyse the effect of grouting of high-moisture quick-concreting material into broken coal seam . 3 main factors include the proportion of grain diameter of coal ( grain diameter is <5mm，5～20mm and >20mm separately ) , the water cement ratio of grout ( 1.5 : 1 , 1.8 : 1 and 2.0 : 1 ) and the grouting quantity ( 160ml , 200ml , 220ml ,240ml , 260ml , 280ml , 300ml , 320ml and 360ml ) .

Although CVD diamond film has good potential outstanding properties, the columnar growth of CVD diamond results in a polycrystalline nature and the grain size increase with film thickness [4].
However, one also finds that the increase in load causes the increase of the number of micro-cracks.
For as-grown polycrystalline diamond film, it shows very rough surface and contains well-facet crystalline with the average grain size of approximately 8 µm.
When the polished area get larger, the pits of grain boundaries decrease therefore the finer surface roughness.
For the unpolished diamond film, the full-width half magnitude (FWHM) is less than 10 wave numbers at 1332 cm -1 Raman peak, and only one weak trace of non-diamond inclusion was identified, which reveals good quality of the as-grown diamond.

The formation of single phase YAG powder specimens requires repeated calcination and prolonged heating (∼12 h) [6] which, at elevated temperatures (>1800°C), induce grain coarsening.
Therefore, the obtained particles tend to exhibit a large grain size, irregular morphology and a wide size distribution.
The unusual behaviour of the strain may be related to the mechanism of segregation of europium atoms from the cubic lattice of garnet which, for intermediate thermal treatments, leave a certain number of vacancies.
It is possible that these junctions contain a large number of grain boundaries that in turn they may preferentially accumulate Eu species, which suggests where the Eu may be segregated.

In addition to the protective coatings above, a number of different precious metals and their combinations have been proposed in this paper.
Since the early 1960s, a number of attempts were made to produce coatings of iridium on various refractory substrates, but without much success.
Grain size of Iridium particles is about 0.1 microns.
After oxidation at 1400℃ in air atmosphere for 1h, the grain size became larger (figure 5) .
The coating consisted of the compacted columnar grains with lots of nano voids appeared on the interface between the coating and the substrate.