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Introduction Foam concrete refers to a concrete building material which contains a large number of pores, and has the advantages of fire resistance, heat insulation, sound insulation, seismic resistance and light-weight.
Table 1 Properties of cement Fineness (%) Standard consistency (%) The initial setting time The final setting time Stability (Pat method) Compressive strength (MPa) Flexural strength (MPa) Heat of hydration (kJ/kg) 3d 28d 3d 28d 3d 28d 0.4 28.1 185min 240min No crack 23.9 46.7 3.8 6.8 246 279 Table 2 Chemical composition of cement (%) SiO2 Fe2O3 Al2O3 CaO MgO SO3 Total alkali content Loss on ignition 22.04 2.65 6.29 58.99 2.53 2.47 0.72 3.06 Table 3 Brief introduction of the pulverized limestone Place of Origin Specific surface area cm2/g The content of available CaCO3 Chongqing 210 >99% 290 440 Table 4 Content of the foam concrete mixture Composition Cement /kg Water /kg Limestone /kg Foam /M3 Calcium chloride /kg Content 450 180 0 0.68 2.25 Table 5 Designed mixture ratio for different fineness of the limestone  Number Cement /kg Water /kg Limestone /kg Foam /M3 The fineness of limestone cm2/g Calcium chloride /kg 1 360 180 90 0.64 210 2.25 2 360 180 90 0.64 290
2.25 3 360 180 90 0.64 440 2.25 Table 6 Designed mixture ratio for different limestone and foam Number Cement /Kg Water /Kg Limestone /Kg Foam /M3 Calcium chloride /Kg 1 450 180 0 0.68 2.25 2 427.5 180 22.5 0.68 2.25 3 405 180 45 0.67 2.25 4 382.5 180 67.5 0.66 2.25 5 360 180 90 0.64 2.25 6 337.5 180 112.5 0.63 2.25 7 315 180 135 0.625 2.25 8 292.5 180 157.5 0.62 2.25 Test equipment.
At the same time, it has good filling effect, due to that the limestone powder has fine grains, which can fill in the crystal interface transition zone of cement stone and form a compact wall of the foam concrete, then the strength of the foam concrete increases.

Sixian City is located in Anhui Province northeast, Tuo River, Xinbian River, old Sui River flowing through the territory and climate resources superior, convenient transportation, Sixian District is the country 's important commodity grain production base.
At the same time, soil heavy metal pollution is increasingly prominent because of a large number of waste, emissions and the extensive use of pesticides and chemical fertilizers.
Studies have shown that the vehicle fuel combustion will produce a large number of Pb and use of automotive lubricants, metal parts and tire wear will result in a large number containing Cu and Zn dust, so we can say Cu, Zn and Pb may be derived from the traffic pollution.

Under normal circumstances, the value of the proportional coefficient is a positive number.
Regression Forecasting.Suppose the number of ( ) was about the data recorded the planting quantity and profit of industrial crops in some area many years ago, and they are distribute around a straight line, the function relation between the total profit in this year and the planting total in next year is found using the linear regression method.
If the number of ( ) don’t distribute around a straight line, the method of the variable replacement can be used to transform the nonlinear function into the linear function relation.
The farmers are eager to sell their grain in order to reduce their loss and stored cost, speed up their funds turnover on the conditions of supply and demand in rural industrial crops.

As a result, abundant metastable surface microstructures or phase structures, such as supersaturated solid solution [1], ultra-fine grain [3] and nanostructures [5] are formed within the irradiated surface layer.
Compared with Fig. 1 (a) and 1 (b), one can see that the number density of craters of 5-pulsed sample is obviously higher than that of 10-pulsed sample, indicating that the number density of craters decreases with the pulses increase.
The number density of craters of 5-pulsed sample is obviously higher than that of 10-pulses.

Experiment with grain-size distribution and specific gravity test, were carry on to calculate soil textural classes and soil hydraulic characteristic.
Minimizing the number of compartments will decrease calculation time, and might increase the mass balance error.
For each soil layer, the bottom compartment number is defined.
The soil layers are numbered from top to bottom (the first soil layer is 0-60 cm, the second soil layer is 60-120cm, the third soil layers is 120-260 cm).

The control of the maximum paste thickness (MPT) allows the reduction of the coarse particles interference, minimizing the number of contact points among the grains and avoiding the formation of an aggregate skeleton that impairs the flowability of the mixture.
However, using MPT in the optimisation of particulate systems with small dimensions (< 100 µm) is not as simple as the maximisation of its value because the number of coarse particles might be insufficient.

The glass attenuation depends on the grain size, viscous friction, crystal structure, porosity and hardness.
The amount of energy lost through absorption depends upon the elastic properties of the material being tested [16] while loss due to scattering in materials also depends on the ratio of grain size and wavelength [6].
Moreover, this is due to the fact that the number of Te-O linkages is increased which means the decrease in non-bridging oxygen in the glass network.

Microstructure observation by SEM elucidates that plastic deformation proceeds without generating severe cracks and all the grains are heavily deformed.
SEM observation showed that the oxide consisted of equiaxed small crystal grains, which can be imagined from the microstructure after a slight deformation given by Fig. 5(a).
On the other hand, the limited number of slip system Fig. 6 The effect of high temperature deformation on the texture 　　　 　　　　development 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 0.0 0.5 1.0 1.5 2.0 True Strain Texture Sharpness Fig. 6 The effect of high temperature deformation on the texture 　　　 　　　　development 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 0.0 0.5 1.0 1.5 2.0 True Strain Texture Sharpness (a) (b) Fig. 5 SEM micrographs showing the microstructure observed after the deformation up to true strains of (a) -0.47 and (b) -0.90.

Experimental results indicate that open porosity decreased and bulk density increased with the numbers of infiltration cycle.
Morphological observations also show that the number of open pores at surface site for these materials decreased and they exhibited a denser and smoother morphology as the number of infiltration cycle increased.
Introduction: Boehmite (�-AlOOH), an aluminium hydroxide, is one of the candidate precursor materials for fine grained low temperature alumina ceramics.
As expected, the open porosity decreased and bulk density increased as the number of infiltration cycles increased.
Conclusion The open porosity decreased and bulk density increased with the numbers of infiltration cycle.

(Fig. 1) Very clearly, by plating for longer time, we increase not only the size of the NPs but also the number of Au NPs formed on the HMDS mask.
(Fig. 2) Again, by increasing the temperature, we increase the size of the Au NPs and the number of NPs formed on the HMDS mask.
(Fig. 3) By increasing HF concentration (decreasing the pH), we increase the size of the Au NPs and the number of Au NPs formed on the HMDS mask.
In order to synthesize nanorings with small Au grains, gelatin has been added to the electroless plating solution; the isolated pattern of Au has been deposited under the same conditions with 2% gelatin.