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Introduction T91 steels (ASME SA-213T91/P91), as a representative type of high Cr ferritic heat-resistant steels, has been recognized as the preferable materials and widely used in high-temperature structural components such as header and main steam pipe in advanced power plants due to the good high-temperature endurance, creep resistance properties, excellent heat conductivity, low thermal expansion coefficient and high performance-cost ratio [1-4].
Thus, a considerable amount of experimental work has been performed on the understanding of the evolution of microstructure, mechanical properties, and strengthening mechanism of T91 steels [5-7].
Austenitization process plays an important role in steels since it affect the final microstructure of the sample and, consequently, the mechanical properties of material.
Therefore, it is primarily important to understand the kinetics of nucleation and growth in the process of austenitization for the adjustment of the microstructure and thus the tuning of the properties of materials.
Fresh specimens were used for each dilatometric measurement cycles, to ensure that for each measurement the specimen had the same initial structure and thermal/mechanical history.

Diesel oil migration process The development tendency of diesel oil migration process is similar to gasoline because their physical properties are similar and diesel oil is also atmospheric storage.
The influencing factors, such as phase state, gravity, capillary force, viscous force, gas-liquid interaction and interior resistance of porous media, etc., control three fuels infiltration.
Gasoline and diesel oil are hydrocarbon mixture and some of their properties are given in table 1.
We can see the direction of propane gas flow is influenced by these factors including the leak velocity direction, gravity, position of the outlet and the tank wall shape.
It is affected obviously by gravity.

As more and more kinds and widely using of the Concrete chemical additive, it has become an important factor affects the concrete admixture.
The reasons caused concrete durability and its evaluation methods. 1.1 The reasons caused concrete durability The durability of the concrete structure refers to the character that concrete structures keep their own work ability in the natural environment, the using environment and under the action of the concrete internal factors, or in other words, the structure resistance ability against the destructive erosion of external and internal environments in the design service life.
Its influence factors can be divided into the following several aspects: (1)Environment aspect The environments which concrete is in have important influence on the durability of concrete.
Freezing and thawing experiment method used the Quick frozen method in the national standard common concrete mechanical properties and durability performance test method （GB/T50082-2009） [2] (2)Water permeability evaluation After 28 standard curing days Concrete specimen is under pressure from the hydraulic pressure 0.2 MPa ， la every 8 h increasing the water pressure 0.1 MPa till to 2.0 MPa pressure, and always watching out specimen head face for water seepage conditions.
Conclusion The bleed air performance of concrete admixture has much effect on the mechanical properties and durability of concrete, specifically as follows: (1) Concrete strength The adding of admixture can increase the air content of concrete, and reduce the water cement ratio.

It is relatively very stable material with high lifetime, but in most of the cases is during its use exposed to various destructive factors.
It could be for mechanical straining, temperature, but especially effect by aggressive gases and liquids.
This is very clear in environment with higher concentration of aggressive factors which degradates surface layer of the concrete and allows gasses and moisture later impact throw pore tracts reinforcement in construction.[1,2] This in its final consequence leads to gradual degradation above all venerable parts, cement matrix and later to corrosion of reinforcement in concrete.
Properties of building structures protected by these materials, as for example resistance against water pressure, resistance against oil, gases, and many chemicals has been already many times proofed and described. [3,4,5] Functional principle Crystalline products are dry powder compounds composed of Portland cement, silica sand and many active, proprietary chemicals.
As can be seen on Fig 2, even after 18 months in effect by concentrated SO2 medium impact, results of S2 treatment did not show any dramatical decrease of water tightness properties.

In many cases, it’s only possible to use a certain portion of the recycled material, which depends on numerous factors, mostly on the type of processing.
Before the use of the concrete, the factors of fraction, impact on load-bearing values, water absorption and icing must be taken in mind.
The key elements of the decision-making process for the use of recycled materials include the properties and the possibilities of recycling.
Waste has different properties and the recycling differs as well.
All these factors must be considered when deciding on the use of recycled material.

Asynchronous phenomenon of the ring truss deployable antenna Xinyan Wu1,a, Anping Luo2,b 1Zhejiang institute of mechanical & electrical engineering Co.
LTD, China 2Zhejiang Jianyu property management Co.
The deployable structure of the ring truss have advantage properties, which can be used as an effective supporting structure of deployable antenna.
Dynamics theory including constraint equations and considering friction factor are built firstly.
First, the paper set up specialized constrained equations which can reflect the structure geometry and physical features, especially considering the influence of friction factors.

Based on the FTA of electronic-control engine start fault diagnosis analysis JianChun Gong1, a, DengRong Zhou2,b, ZongBiao Lu3,c ,ZhongFa Mao4,d 1,3 College of Mechanical Engineering PanZhiHua University, SiChuang, china ,617000 2College of Information and Electric Engineering Panzhihua University, SiChuang,china ,617000 4College of Mechanical Engineering ChongQing University, ChongQing, china,400044 a jcgong01@163.com, b 494982494 @qq.com , c 675905252@qq.com, d565258128@qq.com Keywords: electronic control fuel injection engine; fault tree; cut sets; fault Abstract.
By making qualitative analysis, finding out the main influence factors of failure, and putting forward quite perfect methods of removing fault, which providing electronic fuel injection engine maintenance with the beneficial reference.
Therefore, This article attempts to make a comprehensive analysis and discussion to the electronic control fuel injection engine can’t start, and it aims mainly at the engine can not normal starting phenomenon in the life cycle from the fault tree analysis point of view, finding out the main factors of leading to failure, and put forward the corresponding maintenance measures to improve the safety and reliability of the system.
Engine start failure with fire signs Ignition system fault Mechanical system failure Fuel system fault B16 B17 B15 B14 B11 B13 B12 B Control system fault Injector fault Fuel system doesn’t work properly B5 B4 B7 B6 B3 B2 B1 B10 B9 B8 Fig 2 Electronic control fuel injection engine fault tree FT 2.2 Using the minimum cut set for the evaluation of the fault tree Here we use F-V (Fussell - Vesely) algorithm to confirm the minimum cut set, and carrying out it in sequence from the top event, among which need to use logic gate properties, logic “and” door only increase the capacity of the cut set (fault number), and logic” or” gate increase cut set quantity.
Application of reliability theory and fault tree analysis method, through the establishment of fault tree diagram, making the probability analysis of the top event and the importance degree analysis of the bottom event to the engine fail to start, and find out the electronic fuel injection engine the main factors of start failure, so that saving a lot of time and cost for the maintenance staff. 3 Fault removing methods Through the fault tree analysis, we can obtain the main factors of affecting the electronic fuel injection engine fail to start, then maintenance can be easily carried out.

Broken teeth as a key vulnerability crusher parts, its wear resistance directly affect the productivity and life.
resistance Comprehensive analysis of alloying elements and heat treatment on properties of materials, improved formulation and production process 4.
(2) Steel C, Mn content increased, the hardness increased, decreased impact toughness, in which the greatest influence Mn, C second; Si, MO less influence on the properties of steel are in the middle of obtaining the performance levels the best value.
(3) After testing the mechanical properties obtained material after 870 × 1.5h with the oven cold +880 × 1.5h oil quenched +250 × 2h annealing, the hardness of HRC45, impact toughness = 40J/cm2, Field Application broken tooth can completely meet the application's working conditions.
Modern Casting，Marehl990 [3]Delia.A.et.al Effect of austenitizing conditions on the impact properties of an alloyed austempered ductile iron of initially ferritic matrix Structure[J].Damage Mech，1998，7(2):103～128

Although only mechanical pressure provided by a nip roll was applied during the calendering process, the experimental results indicate that the calendering process should be useful for enhancing the surface quality of roll-to-roll printed electronics products.
If it is beyond the specifications, it should affect the printing quality of the next layer and eventually the overall capability of device.
Another factor to be considered is the electrical conductivity.
Therefore electrical properties of pattern are also expected to change.
Future work should include experiments with the heating roll and analysis to find out critical factors for the quality enhancement.

In this paper, regardless of the cooling system of the mold, the optimization design for the material distribution of heterogeneous injection mold is investigated, which is made of two base materials with different thermo-mechanical properties.
Material Properties Description of Heterogeneous Mold Assume that the mold is composed of two constituent particles 1M and 2M with different material properties 1Mπ and 2Mπ .The overall properties at any point P inside the mold are determined by the linear rule of mixtures[1,2]: 1 2 1 2 1 2, 1 P M M f f f f π π Π = ⋅ + ⋅ + = (1) where 1f and 2f are the volume fractions of material 1M and 2M , respectively.
During the solidification process of casting, the uniformity of casting temperature distribution significantly affects the finished part quality.
Considering the von Mises stress constraints of the mold, the mathematical model of the material optimization of heterogeneous mold is formulated as follows: nix Ne eXe ts XFwXFw Minimize i me Nee ,,2,110 .,,2,1 ),(max.. )()( 0 22 11 L L =≤≤ =≤ ⋅+⋅ ∈ σ σ (5) where 1w and 2w are weight factors, respectively, Ne is the element number of the mold, 0σ is the inherent allowable stress of the mold, meσ is the von Mises stress of the e-th element of the mold.
The convection properties: h=1600W/m2℃, Ta=20℃. 0σ =830MPa.