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Observation from cast thin section showed that most of microcracks is structural - diagenetic fracture except a small number of diagenetic fractures, structural - diagenetic fracture can be further divided into intragranular fracture, grain- edged fracture and transgranular fractures
Primary intergranular pores formed after diagenetic compaction, small space formed between sedimentary clastic particles with grain-supported, this type of pores has different pore size, regular and nearly triangular shape.
(3) intragranular pore The intragranular pore is mainly secondary intragranular pore, it formed from feldspar, debris and other more unstable mineral grains corrosion or first fragmentation then erosion, minerals feldspar, mica, usually got selective dissolution along the cleavage or the twin plane as well as the broken surface, formed intragranular strip or honeycomb shape, when they are Subjected to strong corrosion, mould hole is formed or communicat with the intergranular dissolved pore, so porosity and permeability is greatly improved
There is serious sliming fracture in this kind of reservoir, which results in a large number of intrastratal fractures, broken crack blocked.

A number of factors define the metallurgical structure in Al-Si castings and that determines the properties.
The primary importance are dendrite cell size or dendrite arm spacing, the form and distribution of microstructural phases (eutectic structure, the size and distribution of intermetallics) and grain size.
Besides of heat treatment also modifying and grain refining can be used for optimization of structure parameters morphology.
Molten metal was purified with salt AlCu4B6 before casting and was not modified or grain refined.
A minimum number of five test specimens from each state (untreated, T4, and T6 heat treated) were used for tensile test.

Table 1 Parameters of strain at individual simulations Simulated tube wall thickness Pass number eh ė eh(total) Final cooling rate [-] [s-1] [-] [°C.s-1] 6.3 mm 1. 0.33 4.8 1.77 0.70 2. 0.49 21.8 3. 0,95 21.8 20 mm 1. 0.28 3.9 1.27 0.44 2. 0.33 12.4 3. 0.66 12.4 40 mm 1. 0.21 3.1 0.85 0.25 2. 0.22 8.2 3. 0.42 8.2 Table 2 Variants of temperature at individual passes Pass number variant „A“ variant „B“ variant „C“ variant „D“ T vcool.
The microstructure of the specimens after the plastometric simulations reflects the different size of the initial austenitic grain and it is formed by a mixture of bainite, ferrite and perlite in different proportions.
After heat treatment, the microstructure of all 12 specimens was formed by quenched phases and differed more or less only by the degree of visualization of the original austenitic grain – see Fig. 6.
Microstructural differences of the specimens after rolling simulation (grain size, proportions of phase components) were eliminated by subsequent quenching from 850 °C and tempering at 680 °C.

The precipitation of fine and stable carbides in steels is very effective for grain size refining and precipitation hardening, and will benefit the improving of mechanical properties [4-6].
Fig.1 OM structures of the (a) 0W and (b) 0.1W cast steels Fig. 2 shows the dependences of impact energy on the tested specimen number of both the 0W and 0.1W steels.
Fig.2 Dependences of impact energy on the tested specimen number of 0W and 0.1W steels.
Fig.3 Fracture surfaces of the (a) 0W and (b) 0.1W steels after Charpy impact tests Cast steels possess coarse grains and inhomogeneous microstructure.
The improvement of tensile properties of the 0W steel after W addition is closely related to the roles of W played in the aspects of grain size, microstructure, precipitate, interlamellar spacing of pearlite, and solid solution strengthening [1,8].

Owing to its unique properties, carbon (in various forms, including graphite, diamond, graphene and nanotubes) can find a great number of industrial applications, also as a result of its using in the technology of composite materials.
There are a great number of manufacturing methods of Cu-C [8-10], including: - Cu-C as a bulk material: microwave sintering, hot-pressing, spark plasma sintering, cold pressing, hot-isostatic pressing, liquid infiltration and diffusion bonding, - Cu-C as layers: microwave plasma-enhanced chemical vapour deposition and tape casting.
Materials and experimental procedure The mixtures of copper powders (produced by Aldrich, having a dendritic shape, grain size of 3 mm and purity of 99,8%) doped with carbon with the volume fraction of 3% were prepared for the purpose of the technological trials.
The following carbon forms of various types were used: - short nanotubes – by Aldrich, diameter between 110 and 170, length between 0,5 and 2 μm, - long nanotubes – by NanoAmor, diameter between 50 and 80, length between 5 and 9 μm, - graphite nanopowder – by Aldrich, grain size of 30 nm, specific surface >100 m2/g, - graphene powder – by SkySpring Nanomaterials, particle size between 1 and 5 nm.
The grain boundaries of the copper matrix were coated with these powders, thus creating a continuous structure without visible microstructural defects.

Re decreases the number of oxygen existed in the coating.
When the rare earth element Re was added in Al-Zn-Si coating, although the addition of rare earth element Re for Al-Zn-Si coating could not change the component of corrosion products, it could decrease the number of oxygen existed in the coating.
Furthermore, Re mainly enriched on grain boundaries, reinforces and hinders grain growth, and the eutectic structure can hinder the crack propagation [10, 11].

The model will enable an improvement in the forming process, refinement in the design of the fan blade and a model to evaluate new alloys or refinements to grain size or texture in existing alloys.
The steady increase in hardening of the alloy observed is attributed to concurrent static and dynamic grain growth [3] which develops at SPF temperature.
The grain size for the results displayed in Fig. 2 before testing the alloy is reported as 6.4 mm.
The number of elements through the core sheet thickness on the plane section is five.
Thus the number of 8 node solid elements in the two skin sheets totals 182718, and for the core sheet the number of 4 node shell elements totals 168553.

It includes a number of typical parameters: the effectiveness of the business, transmission delay, jitter, packet loss rate and network throughput.
This system can provide the most fine-grained quality of service distinction.
(2) MF (Multi-Field) classifier: It classifies the packets according to the combination contents of the packet header in the multiple domains such as source address, destination address, DS field, protocol identifier, source port number and destination port number, etc.
Integrated service and Differentiated service comparison (1) Different Service granularity The Integrated service model is a fine-grained QoS based on data stream but the Differentiated service model is a coarse-grained QoS
The delay is relatively large with the increasing of packet number in the general network if the complementary strategy is not used.

The machining parameters considered for the study are Abrasive Grain Size (AGS) and Hydraulic Pressure (HP) and Stand Off Distance (SOD) and the Abrasive Flow Rate (AFR).
CCD is used when number of factors involved for sequential experimentation is more.
Box-Behnken Designs (BBD) usually have fewer design points than central composite designs, thus, they are less expensive to run with the same number of factors.
Standoff distance is the significant factors for surface roughness followed by abrasive grain size.
The most important aspect affecting surface polish is the abrasive grain size.

,Xuanhua,Hebei,China a wweizhi@126.com Key words: Fine-disseminated Hematite, Stage grinding, High-intensity magnetic separation, Reverse flotation Abstract: The mineral processing experimental research was carried out on the hematite bearing characteristics of low grade, fine grain,complex composition.
Because the dissemination size of iron minerals in the ore is uneven, the process flow of stage grinding - stage separation is selected, which can discard some coarse-grained quartz, recover iron minerals of monomer dissociation early, reduce the follow-up workload and reduce beneficiation costs.
Product Name Yield Grade Recovery activity for raw ore activity for raw ore HIMS concentrate 43.81 12.78 44.83 75.29 24.23 HIMS tailings 56.19 16.39 11.47 24.71 7.95 Ore feeding 100 29.17 26.08 100.00 32.18 Tests on LIMS-HIMS- Reverse flotation progress for recovery of weakly magnetic minerals Preparation of strong magnetic concentrate for first stage The crude concentrates of first stage were prepared under the conditions of the pulsation number of 120 times / min, a stroke of 20mm, the magnetic field strength of 8500 Oe Using the slon-500 vertical ring pulsating magnetic machine for the weak magnetic tailings obtained in the above step.