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The effect of the pore on the mechanical properties of sintered parts has long been studied by a large number of researchers.
There have been a large number of researches on the effect of porosity on the mechanical properties of sintered parts [3~6].
Individual grains were evident in the specimens sintered at the temperatures of 1250o C and above.
In a large number of studies, equations relating the ductility of a sintered part to its fractional porosity have been developed.
In the low-density region, i.e. the initial stage of sintering process, the elongation is directly proportional to the load bearing area projected on the plane normal to the tensile axis, and the following equation can be developed; u rel f i 1  δ η δ = −  δ η  (4) where δu and δf are, respectively, uniform and fracture elongations of pore free material, η is the porosity during sintering process and ηi the initial porosity denoting the stacking structure, i.e. the number of the nearest neighbor powders.

Dongting Lake is an important commodity grain, cotton, oil, fish production base in Hunan Province, is an important light industry and petrochemical base, with Yueyang, Yiyang, Changde and other cities and a number of cities and towns, and relying on its traffic advantage, become an important regional connection CZT City, Wuhan city circle, butt Yangtze River Delta, Pearl River Delta, Chengdu-Chongqing economic zone.
Overload, the actual number of people (P) is greater than the population can carry (Cs).
Surplus, the actual number of people (P) is less than the population can carry less than the actual population (Cs).Critical, the actual number of people (P) is equal to the population can carry (Cs).

Post-deposition annealing treatments are used to improve the emission intensity of the RE ions and the film structure causing crystallization and grain coarsening [6, 7].
The increment of the Tb emission can be attributed to the reduction of defects and the activation of optically active Tb sites, which is influenced by the number of oxygen atoms associated with each Tb ion [10].
Acknoledgements This work was funded by the Peruvian science foundation FONDECYT under the projects “Círculos de investigación en ciencia y tecnología-2”, contract number 011-2014 and under the cooperation project with the German academic exchange service (DAAD), contract number 035-2016.
The authors also gratefully acknowledge the support of Karem Tucto and Loreleyn Flores by CONCYTEC under the contract numbers 012-2013-FONDECYT and 000236-2015-FONDECYT-DE, respectivley.

Each copper nodule is made up by a large number of crystallites.
TEM micrograph shows a large number of crystallites with size ranging from 30-70 nm.
Fine crystallites indicate that a large number of atoms are trapped in the crystallite boundaries.
Higher energy zones like grain boundaries and twin boundaries [7] helps rapid biocidal effect due to the fast releasing of copper ions.
Each nodule is made up of a number of fine crystallites (size~50 nm).

But 304 stainless steel in the chloride ions environment is very sensitive, the results show that the presence of chloride ions in the environment is considered to be the one of the main reason of the local corrosion of 304 stainless steel, because the radius of chloride ion is small, have the strong ability through the passive film, resulting in the destruction of the passive film[1], duo to pitting corrosion at last; Chloride ions also could engender Cr-Cl compounds with Cr of the grain boundary, make the stainless steel generated the Cr depleted area, due to the crystal boundary corrosion[2]; 304 stainless steel also have stress corrosion under low stress.
After sometimes found a number of cooling pipe have pitting corrosion, the pitting corrosion holes are through the pipe itself with irregular shaped, the radius ≤ 3mm.
The cooling liquid in cooling pipe is transparent, shaped pipe wall bright is new, but inner wall of the pipe have a large number of pale yellow sediment.
As shown in Figure 1, Figure 1 (a) is take the Metallographic photo far away from the hole of pitting corrosion, the organization is the austenitic matrix with a small amount of ferrite and a small amount of black carbon precipitation, the basic is not caused by corrosion; Figure 1 (b) is the metallographic photo of the area near the pitting corrosion holes and clearly see many stress corrosion cracks are extend from the hole of pitting corrosion at the origin and cross the intersection, they show herringbone; Surface is dark color and clearly see both sides of the crack have a large number of new pitting corrosion holes.
The results are shown in Table 1: Tab.1 The Cr content changes with the distance from the pitting corrosion hole Number The distance from the pitting corrosion hole Cr content 1 1mm 15.460% 2 5mm 16.97% 3 9mm 17.25% From the table.1, the area more near from the pitting corrosion hole, the lower of Cr content.

Introduction Fluid mud is a special movement form for fine-grained cohesive sediment, and widespread phenomenon observed in muddy coast and/or estuary region.
The forming process of fluid mud can be described as follows: in salinity water, fine-grained cohesive sediment settlement is described no longer effectively by the single particle settlement theory but the flocculation theory.
Taking muddy coasts as example, during extreme weather days such as Typhoon, fine-grained cohesive sediment on the nearshore seabed can be re-suspended due to the fierce impact of wave and tide.
The medium grain size D50 of suspended sediments ranges from 0.002mm to 0.004mm based on historical field observations.
According to the relationship of sediment concentration and wave height indicated in Fig.3 and Fig.4, the corresponding wave height should be relatively larger, thus it can bring more energy to re-suspend the fine-grained cohesive siltation on seabed; (3) For the high rank of navigation channel such as 300,000DWT, the critical sediment concentration for fluid mud formation reduces to the range of 0.69-1.26kg/m3, and it is smaller due to the large water depth.

The risk of undesirable spot welds led to the increasing of number of welds by approximately 20 %, which is time, energy and cost consumption [5].
The most important is the distribution of hard martensite grains in ferrite matrix.
The islands of martensite are dispersed around ferrite grains (amount of 10 to 30%).
Base metal of welded sample consists of a fine-grained structure with the ferritic matrix and island of the martensite.
The area of weld metal consists of coarse-grained structure of martensite as a consequence of rapid heating and subsequent cooling during the resistance welding process.

The tailings in some mines usually contain a large number of valuable elements which can be comprehensively recovered [1-2].
Part of chalcopyrite is immersed in gangues as micro-grained particles, which is difficult to liberate even if fine grinding, so both the recovery and the concentrate grade of copper will be affected.
It is filled with the gangue minerals in the fissures of part of broken pyrite, and a little amount of pyrite impregnates in gangues as micro-grained particles, and a little also disseminates in granular or irregular form of monomers.
Micro-grained magnetite can be seen to be immersed in the gangues, which is difficult to liberate from the gangues during grinding and would be partly lost in the tailings owing to its fine dissemination size and close combination with the gangues.
It is difficult to beneficiate the sulfur minerals as a result of high content of slimes, kaolinite etc. easy-to-slime minerals, and the micro-grained dissemination of part of the sulfur minerals (the occupation rate of pyrite in the fraction of less than 0.010mm reaches up to 11.41%).

It is difficult to limit the thickness of the wheels for diamond grains must be coated on the surface of wheel body.
The dimension of the wheel was 150mm(D)×0.5mm(H)×31.75(d)mm, and diamond grain size of the brazed wheel was 325-380μm.
In addition, from the structure of fabricated diamond cut-off wheel, the number of diamonds for the cutting around the wheel circle was fewer than those of traditional sintered diamond wheel.

Table 1 The engineering characteristics of silt Table 2 Grain composition of silt Specific gravity of silt particle Gs Plastic Limit WP Liquid Limit WL Plastic Limit index Ip Maximum dry density g/cm3 Best moisture content wop% 2.71 26.4% 34% 7.6 1.52 22 Grain compo-sition (mm) 2~0.5 0.5~0.25 0.25~0.075 0.075~ 0.005 <0.005 silt 1.6% 1.2% 8.1% 75.9% 13.2% 3.2 Analysis of triaxial test We use Consolidation-Undrained test to investigate the strength of silt with the addition of different microbes.
(2)Ion effect Polysaccharide is a kind of linear coiling of polymer, the molecule has a lot of contact point, and contains a large number of functional groups, such as R - COOH, R-CH2-OH, the dissociation of these functional groups can make strong ions exchange, and have physical and chemical reaction with ions in silt, forming a cementitious material, which will cement dispersive silt particle together, improving the interaction between particles and silt strength.