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., Chengdu 610021, China adhf8010@126.com, bshowseal@yahoo.cn, czhumin2006105131@126.com, d287685258@qq.com, e2010696@qq.com Keywords: steel-lined, penstock, concrete crack, cracking width Abstract: According to mechanic properties of steel-lined reinforced concrete penstock, author abstracted and simplified its mechanical model, designed and produced 20 axis tensile structures of reinforced concrete, and proposed the test methods on the ratio of crack widths on two sides of concrete protective covering.
It can be found in survey [4] that some penstocks those have been built have large cracks on the surface (even come to 1.7mm), which may affect the durability of outer reinforcement of penstock, but it's difficult to test the width of concrete cracks in the outer reinforcement on site.
Fig.1 Axial Tension Component of Reinforced Concrete According to previous studies, covering thickness, concrete strength, reinforcement diameter, superficial form of reinforcement, reinforcement spacing, reinforcement ratio, and etc. may affect the width of concrete cracks, and 20 specimens were Designed and produced on the basis of considering these factors, which are shown in Table 1.
The main reasons for the difference between crack widths on two sides are variability of material properties, approximation of calculation model and limitation of measurement accuracy.
Conclusions According to mechanic properties of steel-lined reinforced concrete penstock, its mechanical model is simplified as axial tension component of reinforced concrete, and the crack widths on two sides of concrete protective covering are measured and analyzed by test method.

The main aim of the present research is to improve the structure of the briquette and to observe basic fuel properties of durian peels in the presence of calcium hydroxide.
Therefore, the main focus of this research is to compare the properties of durian peels briquette in the presence of the binder calcium hydroxide.
Hameed, Textural porosity, surface chemistry and adsorptive properties of durian shell derived activated carbon prepared by microwave assisted sodium hydroxide activation, Chem.
Morey, Factors affecting strength and durability of densified biomass products, Biomass Bioenergy. 33 (2009) 337-359
Hurst, Microwave and slow pyrolysis biochar-Comparison of physical and functional properties, J.

Nevertheless, poplar has low density and poor mechanical strength.
Bonding strength test According to the test methods of type- II plywood of GB/T 17657-1999《test methods of evaluating the properties of wood-based panels and surface decorated wood-based panels》, test the bonding strength of samples.
The small size effect of micro/nano fibrils augmented the contact area of bean glue and poplar veneer, and then strengthened the interface properties of plywood.
As the second edothermic peak in figure 1, the unfolding of soybean glue was a coopertive transformation accompany with decalescence phenomenon, while the structure and distribution of hydrophobic and hydrophilic groups on the protein surface greatly affect protein–protein and protein–substrate interactions and therefore must affect soy protein gluing strength.
The real line tand1 is dissipation factor of blank soybean glue, and the broken line tand2 dissipation factor of 1% micro/nano fibrils addition soybean glue.

The mechanical properties of steels are strictly connected to chemical composition as well as to microstructural features obtained after thermo-mechanical processing.
As a consequence, recrystallization and grain growth are relevant to the mechanical properties of steels, thus suggesting the necessity of mathematical models able to predict the microstructural evolution after thermo-mechanical cycles.
In particular, in stainless steel grades, mechanical characteristics, and a proper microstructure with an adequate grain size distribution, are very important in order to achieve the required formability and deep drawing properties for many applications.
In order to achieve such ability, not only mechanical properties but also an adequate microstructure of the product is needed.
This is the reason why there is the need for quantitative models that accurately predict the effect of the processing parameters on the final product in order to control the microstructure and properties of steels during a thermo-mechanical treatment.

The chemical composition and the mechanical properties of the material are presented in Table 1 and Table 2, respectively.
Table 1 Chemical composition of 7050-T7451(wt.%) Zn Cu Mg Zr Fe Si Mn Ti Cr Others Al 6.7 2.5 2.3 0.12 0.13 0.12 0.10 0.06 0.04 0.15 87.9 Table 2 Mechanical properties of 7050-T7451 Yield strength [MPa] Tensile strength [MPa] Elongation [%] Hardness [HB] Young modulus [GPa] 455 510 10 135 71.7 Experimental set-up.
Therefore, it means that the thermal load and mechanical load together affect the surface residual stress.
However, the dominative factor that affects the surface residual stress is the mechanical load due to a relatively small elastic modulus.
The following conclusions can be drawn: (1) The dominative factor that affects the compressive surface residual stress is the mechanical load, especially the strong burnishing effect the tool flank surface produced

It is shown that the clearance has affected the dynamics response of the system and the lubrication is effective to deaden the impact.
The phenomenon can be improved by the lubrication involved in the mechanical system.
The model is more realistic because the elasticity properties of contacting surfaces and the loss of energy in the impact process.
Some factors must be taken into consideration in the force model, such as account material properties, geometric characteristics and the impact velocities of the contact bodies.
Part C, Journal of mechanical engineering science, vol. 210(c3), 1996, pp. 215-223

The viscoelastic surfactant diverting-acidification technology is a new intelligent matrix acidizing technology.Based on the theoretical analysis，viscosity-variable diverting-acid main agent is selected out.Both the rthogonal design and the grey relational analysis are used to determine synthesis conditions and influence of reaction factors.The production structure is verified by the infrared spectra.Then coreflooding experiments are designed to check the diversion effect,and it shows that the system satisfies the need of diverting-acidification in the carbonate formation.
Mechanical and chemical methods are the mainly diverting technologies[1].Mechanical method enables acid to reach the target rigorously,but it is unable to control the flow of acid within the layer;Chemical method is the most widely used technology,but also has many defects.Compared to conventional diverting technology,Viscoelastic surfactant(VES) viscosity-variable diverting-acid technology has many advantages and becomes the research focus.Based on the theoretical analysis, viscosity-variable diverting-acid main agent and its synthesis conditons are selected out,then multi-coreflooding experiments are carried out to measure its diverting capacity.
The gray relational analysis is based on similar or dissimilarity trends of the factors to measure the association degree between them[5].And it can solve the multiple-factor optimization problems in the synthesis.The steps are as follows: a.Determining the conversion rate as reference sequence xo(k),temperature,time,mass ratio,and catalyst amount as comparative sequence xi(k); b.Reference sequence and comparative sequence data are processed values of the dimensionless by (1) c.Calculating the gray correlation coefficientξi(k) between reference sequence and comparative sequence by (2) d.Connection degrees γi are given by （3） Through the orthogonal design and gray correlation analysis,the best reaction conditions are selected out:(1) amidation reaction:170oC, 6.5 hours, catalyst amount 0.5wt%,the mass ratio between 3-dimethylaminopropylamine
Synthesis and Properties of alkylamide phosphate betaine.Journal of East China University of Science and Technology,Vols.24(1998)No.6, 741-745(in Chinese) [4] Z.L.Geng,H.Q.Jiang: Application of Orthogonal Design Methodology in Optimal Parameters of Polymer Flooding.Journal of Southwest Petroleum University, Vol.27(2009)No.5, 119-121(in Chinese) [5] N.Qi,F.J.Zhou and Y.C.Gao:Grey Correlation Analysis of Factors Affecting Sand Production in Sebei Gas Field,Special Oil & Gas Reservoirs,Vols.17(2010)No.1, 100-104(in Chinese) [6] C.M.He,H.J.Chen and F.Li: Study on Viscositify Mechanism of VES Self-diversion Acid, Drilling Fluid & Completion Fluid, Vols27(2010)No.4, 84-86(in Chinese)

Since GBFS has this special hydration-reaction mechanism, its properties of concrete are different OPC.
It studied by physical-mechanical and durability tests by using mixture and hardened with combinations after prepared NSC with GBFS.
Mineral composition of raw materials and physical property follows in Table 1.
This may be related to the insufficient number of experiments and statistical analysis without relevant safety factor of concrete and other factors.
Strength properties.

The mechanical properties and biocompability of the extruded fibres are investigated to study the effect of graphene content. 2.
Mechanical properties were tested using an Instron 5566 Universal Testing Machine.
Mechanical Properties In general, the addition of graphene results in large increases in the tensile strength, yield strength and Young’s modulus of the fibres.
Mechanical properties of extruded fibres [300 – 365 µm] at different graphene contents.
Jin, Fabrication, Mechanical Properties, and Biocompatibility of Graphene-Reinforced Chitosan Composites, Biomacromolecules 11 (2010) 2345-2351

With the arrival of metal additive technologies, the need to analyze and verify the mechanical and structural properties of the printed materials came to light.
The goal is to achieve optimal dimensions, desired surface quality and a combination of many mechanical and physical properties.
All of these factors affect the hardness of the material.
Remelting increases the relative density, which generally leads to better mechanical properties.
Rajtukova, Mechanical properties of powder CoCrW-alloy prepared by AM technology.