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Introduction Non-dispersible underwater concrete is described as tremie concrete, and is a new type concrete which can be poured underwater and whose aggregate and cement slurry separate in water is not like normal concrete. [1] In recent years, the construction of underwater projects is developing prosperously, concrete is still one of the most important and largest demand building materials in underwater engineering and the performance of underwater concrete will directly affect the quality of underwater engineering.
Because of the differences of mechanical property between non-dispersible underwater concrete and normalconcrete, it’s necessary to study the mechanical performance of columns.
The paper will use the experiment analysis way which study the mechanical performance of nomal concrete columns, discuss the mechanical performance features of non-dispersible underwater concrete columns with the experiment of axial compression and eccentric compression and provide a reference for researching non-dispersible underwater concrete.
Finally, taking all factors as a whole, we select secondary anti-washout admixture (UWB-II) which is manufactured by Engineering and Technology Institute of China National Petroleum in 2003.
Table 2: Mechanical property of concrete and longitudinal reinforcement Concrete Longitudinal reinforcement Material fcu(MPa) Ec(GPa) fy(MPa) fu(MPa) Es(GPa) NC 41 28 405 530 200 NDC 33 24 Specimens To better compare with normal concrete, the paper designs 3 groups, 6 concrete short columns (slenderness ratio is 4.5) on the basic of eccentric distance.

One of the most important factors is the reaction temperature.
All of them agreed that during the mixing phase the essential part of ammonium is released so the mechanical properties of the final product remained unaffected.
AAC is a lightweight material with remarkable properties such as fire resistance, thermal and sound insulation and very good structural performance.
The final part of the manufacturing process is the hydrothermal treatment of the prepared green bodies, where the material gains its final properties.
Dilmore and Neufeld [16] examined the influence of the contaminated fly ash to mechanical properties and were concerned about the environmental impact of produced AAC.

Introduction Compared with the noble-metal-based metallic glasses, Cu-based bulk metallic glasses have excellent properties such as high glass forming ability, good mechanical properties and relatively low cost.
Since the successive development of Cu-based bulk metallic glasses by Inoue [1], Johnson and others in the late 90s, much effort [2~4] has been devoted to study the alloy systems, properties and engineering applications of Cu-based bulk metallic glasses.
The ultimate aim of amorphous alloys research is to develop the bulk metallic glasses with high glass forming ability and useful engineering properties.
The alloying elements significantly affected the thermal physical parameters of Cu-based metallic glasses such as crystallization temperatures, glass transition temperatures and liquidus temperatures, which further influenced glass forming ability, thermal stability, corrosion resistance and mechanical properties of metallic glasses [5, 6].
It is well known that bulk glassy alloys with high GFA and large supercooled liquid region usually obey the following three factors [7]: (1) multi-component system consisting of more than three elements, (2) significant atomic size mismatches above about 12% among the three main elements and (3) negative heats of mixing among their elements.

Introduction Titanium and its alloys have been widely used for aerospace, medical, and other applications because of their excellent properties such as high specific strength, good heat resistance and corrosion resistance properties.
Non-uniform green density distribution, coarse particle, gravity and friction are some of the factors that may influence on the distortion of the sintered parts [4].
The average oxygen content was 0.278 mass % after sintering, which is higher than that of the initial powder (0.115 mass %) However, this oxygen content level does not affect the mechanical properties [10].
[2] Miura, H., Takemasu, T., Kuwano, Y., Ito, Y., Kenji, S., Sintering behavior and mechanical properties of injection molded Ti-6Al-4V alloy, J.
-M, Effect of thermal mechanical properties of PIM feedstock on compacts shape retention during debinding process, Trans Nonferrous Met.

Material property data for ABS-HI-121H from LG chemical Co. was supplied by Moldflow.
This may affect the surface morphology change of the product in the smaller cavity.
The resin viscosity would affect the filling-balance in the variable-runner system so that the process parameters influencing the resin viscosity should be considered carefully as the influencing factors to the filling-balance capability of the variable-runner system.
The difference is considered to be affected by the sensitivity of resin viscosity to temperature. 4.
Coulter, Conference proceedings of ASME International Mechanical Engineering Congress & Exposition, Washington, D.C., Vol. 3(2003) [3] D.

Results A summary of the two phase flow properties used in the STAR CCM simulation is given in Table 2; Table 2.
From all the factors available from the simulation, it is necessary to choose between the third exit configuration and the fourth exit configuration to determine a suitable pipe geometry for oil and gas application.
Decision Matrix Criteria Convergence (Iterations) Total Pressure (Pa) Static Pressure (Pa) Velocity (m/s) Pressure Drop (KPa) Rating 7 5 5 10 8 After careful rating of the different flow properties after careful consideration of available literature on the different flow properties, the exit configurations 3 and 4 was compared to each other using each criterion.
The third and the fourth exit configurations were selected to have flow properties that ensures easy flow within the production system as well as lower computational cost.
Qi, Reliability Based ECA Flaw Acceptance Criteria and Safety Factors of Risers and Flowlines.

Introduction Liquid metal forming is to fill liquid metal into molds and cool down to normal temperature, which containing some complex factors influence to cast quality.
Actually, the casting shape, materials diversity and the nonlinearity change of material thermal property make the solidification process to be very complex.
Defining the thermal properties parameters of steel casting and sand mold are listed in Table 1 and Table 2, the primary temperature of casting is 1670°C, the primary temperature of sand mold is 25°C, the air temperature is 23°C, the convection coefficient is 65W/(m2·°C), temperature field distribution and the variation are analyzed.
Figure.1 Steel-casting and sand mold cross-section Table 1 The thermal properties parameters of steel casting temperature°C coefficient of heat conductivity W/( m2·°C) enthalpy (J/m3) 25 29.8 0 1543 31.2 7.5E9 1695 24.5 9.8E9 1670 24.6 1.3E10 Table 2 The thermal properties parameters of sand mold coefficient of heat conductivity W/( m2·°C) Density kg/m3 specific heat J/( kg·°C) 0.52 1630 110 Figure.2 The enthalpy change curve of phase transition process The finite element analysis of casting process temperature field.
Mechanical Structure Finite Element Analysis.

M Casals [4] explains that, researchers analysed 3647 errors in 68 buildings, defects were settled in 3 categories –location, sub-contractors involved, affected building element .it refers failure is due to poor workmanship by subcontractors and the location affected mostly is roofs and floors.
L Sousa [6] observed that, this study looked at two types of stone in Portugal to see how these factors & quality of these stones by analysing mechanical properties, weathering effects, fracture patterns.
Roofs: For bigger buildings in particular, steel trusses, beams, and decking may be common, which affects the percentage overall.

Polyetheretherketone (PEEK) has been considered as a suitable polymer in such coatings based on its biocompatibility and mechanical stability [4].
Among biomaterials with bioactive properties, bioactive glasses (BGs) are well known for their ability to interact with biological fluids inducing the formation of a hydroxyapatite (HAp) layer on the surface, which induces effective attachment of bone in vivo [5].
Among the elements that posses a beneficial effect, boron (B) is very interesting for its ability to stimulate wound healing in vivo, to release growth factors and cytokines, to increase the extracellular matrix turnover and for its role in bone physiology and angiogenesis [7, 8].
XRD analysis (Fig. 1c) confirms the presence of hydroxyapatite already after one day of SBF treatment. 45S5-B1 and 45S5-B3 glasses showed the same behaviour, which indicates that the presence of B2O3 does not modify the bioactivity of 45S5 glass and that it can substitute both SiO2 and P2O5 without affecting the glass reactivity.
Immersion tests in SBF demonstrated thus that incorporation of boron to the 45S5 glass composition does not affect its reactivity in SBF solution.

Goldschmidt introduced a tolerance factor (t), defined by RA, RB, RO are the radius of A, B, and O ions, respectively.
In general, the tolerance factor (t) is 0.8These small changes always have an important impact on the physical and chemical properties in the structure of perovskite materials.
Thus contributing to the properties change of oxygen adsorption and desorption and improving the catalytic activity.
Lu et.al [7]used several methods to synthesis LaMn0.8Mg0.2O3, and discovered the different preparation affect crystal structure, particle size and oxygen species in a large degree; consequently affect the methane catalytic activity.