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A model of attenuation of residual strength with number of cycles has been founded .In this model the constant confined stress and maximum stress of fatigue loading are both considered. 55 specimens of plain concrete are tested under biaxial compressive fatigue loading with constant confined stress.
Introduction For a large number of reinforced concrete structures and prestressed reinforced concrete constructions like nuclear reactor pressure vessels and containment vessels, offshore oil platforms, heavy-dutymachines foundations, bridges, railroad ties, crane runway girders, etc., since they are subjected to long-term cyclic loading, fatigue failure is one of their main failure forms.
The mix ratio of concrete is: cement: sand: gravel: water= 383:663:1154:200(Kg/m3), in which, we employed 32.5# Portland cement produced by Dalian cement plant, medium sand, and gravel with the maximum grain diameter of 15mm.
Determination of Model Coefficients A model of attenuation of residual strength with number of cycles has been founded by the author in reference[9].

Introduction Straw is what’s left over when grains, such as wheat, rice, and barley, are harvested.
First, in areas of grain production, straw is inexpensive.
And more importantly, because straw is now as the waste material from grain production, in many areas in China straw is still burned in fields, producing significant air pollution [1] and increasing the risk of accidents of aircraft and vehicle on highways.
And the dampness or moisture damage in buildings originating from, for example, insufficient ventilation or leaking roofs, with subsequent microbial growth in building materials, has been associated with a number of health effects.

It is indicates the number of lithium complex oxides that react immediately with CO2 at temperatures ranging from the ambient temperature to high temperatures.
The reaction products were board-like powder particles comprising many grains.
The morphology of the grains differed from the degree of reaction and the size of the grains increased as the degree of reaction increased.

In the matrix of the alloy a large number of second phase particles can be seen, which by scanning microscope were identified as a Zn15Ti phase, according to Zn-Ti phase diagram [2]. 0.007wt. % is the mean titanium content in alloy used in current research.
After following rolling passes – after fourth and sixth rolling passes the dendritic microstructure definitely destroyed – the microstructure is fine-grained.
Lower rate of recrystallization of the non-homogenized strip can be explained by the fact that solute atoms remaining in solution as well as small particles are very effective obstacles in grain boundary movement during dynamic recrystallization, for example in the hot rolling process.
This assumption give rise to another question, which is about the possibility of grain boundary movement through the obstacles in non-homogenized material during the dynamic recrystallization in the rolling process.

Thus, the change in transparency of films prepared by using acetylacetone is related to the effect of acetylacetone on the grain growth.
As discussed above, the addition of acetylacetone limits the grain and crystal growth, leading to homogeneously dispersed crystalline nanoparticles no strongly influenced by the annealing temperature.
The number of layers also diminish the resistivity of films due to the increase in thickness.
The homogeneity of film and small grain size allows an elevated optical transmittance.

Grinding speed, depth of cut, feed rate, and wheel properties, such as abrasive material and abrasive grain size, are the dominant parameters for the ball grinding process, as shown in Fig. 1.
As mentioned, the main ball grinding parameters having significant effects on surface roughness are grinding speed, depth of cut, feed, wheel properties, such as abrasive material and abrasive grain size, etc.
Consequently, tool material of the grinder ball with the diameter of 1.5 mm and grain size no. of 150, revolution of the spindle speed, depth of grinding, feed, and stepover were selected as five experimental factors (parameters) and designated as factors A to E (Table 1) for ball grinding in this research.
The S/N ratio, η, is defined by the following equation [5],       −= −= ∑= n i iy n stic characteri quality square mean 1 2 10 10 1 log10) (log10η (1) iy : observations of the quality characteristic under different noise conditions n: number of experiment After the S/N ratio from the experimental data of each L18 orthogonal array was calculated, then the main effect of each factor was determined by using the analysis of variance (ANOVA) technique and the F ratio test [5].

The number of adherent platelets on the anodic oxidation /TiO2 complex one is much less than the anodized one.Accumulation and pseudopodium of platelets are also serious on the surface of anodic oxide film by pseudopodium in Fig. 6a.
Research on microstructures and blood compatibility of Ta-doped TiO2 films on ultrafine-grained Tiournal of Functional Materials[J].
[18] Yu Chunhang, Shao Honghong , XU Xiaojing Zhai Rui.Influence of Mg Interlayer Film on Microstructures and Kinetic Clotting Time of TiO2 Film on Nano-grained Ti,Chinese Journal of Materials Research[J],2010,24(6):669
[24] Yu Chun-hang,Shao Hong-hong.Research on microstructures and blood compatibility of Ta-doped TiO2 films on ultrafine-grained Ti,Chinese Journal of Materials Research[J],2010,3(41):552-554

Recently, a number of waste materials have been used in the stabilization of soils in order to reduce both environmental problems and the requirement for traditional additives such as lime, fly ash, rice husk ash and corncob ash [8, 9, 10].
The grain size distribution curve of soft Bangkok clay is expressed in Fig. 2.
Grain size distribution curve of soft Bangkok clay.
Rachan, Strength development in cement stabilized low plasticity and coarse grained soils: laboratory and field study, Soils and Foundations. 46 (2006) 351-366.

In addition to the alloying concept and deformation temperature (both effecting SFE), grain size and even local texture play an important role [13,17].
The TWIP steel in its as-received condition is characterized by a mean grain size of ~ 2 µm and features high dislocation density and a low fraction of twins [11].
Figure 2: a) EBSD grain map and b) TEM bright-field image depicting the microstructure of the as-received TWIP steel [15].
Based on the number of points depicted in Fig. 4, the findings presented in this study indicate clear trends for the HCF behavior, but of course more tests are needed for statistical evaluation of the results.

The blades used are three in number fixed appropriately with good joining technique / integrated in one piece to withstand the stress of the process.
The image clearly indicates that it is a polycrystalline material due to the impressions of grain boundaries.
Grain boundaries are observed, and the brighter region is the Al element.
The grain growth is hindered by the particulate which obstructs its further growth.