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Hence, dense materials with fine grains can be obtained in a very short holding time [17, 18].
Acknowledgements This research was financially supported by the National Natural Science Foundation of China (Grant Number: 51271091).
The technology project of Jiangxi province Education Department of China (Grant Number: GJJ12420).

Meanwhile we suggest the construction units using Ordinary 32.5 Portland cement of Weifang Cement Workshop, and Ⅱgradation, medium sand, whose sediment percentage 0.39%, air dry, SiO2 >90%, apparent density ρoa=2.469g/cm3 , stacking density ＝1460 Kg/m3 , modulus of fineness 2.9, lime rock reduced stone of continuous grain composition of Weifang, have a grade 5mm-20mm, sediment percentage 0.39%, air dry, native rock strength 55.6±8.9Mpa, apparent density ρoa=2.669g/cm3 , stacking density ＝1560 Kg/m3.
Each batch of concrete volume in about 1000m3 or so, each inspection batch standard maintenance specimen number of about ten group, at the same time around each batch do 5 groups of early rapid maintenance presumption strength, to control the concrete specimens with early strength of concrete quality evaluation.
Conclusions In the application of concrete strength presumption of adopting hot-water method to presumpt 28d standard maintenance intensity early in the process of test, through a large number of test data of a construction site, the commonly concrete strength relationship has good correlation and also can meet the requirements of precision presumption.

Stainless steels are used to replace copper tubes in most power, but a large number of cooper tubes are still applied to air conditioning refrigeration industry.
Table 1 Chemical composition and mechanical properties of copper TP2 and the standard values Items Cu P Rm A50mm Grain size Detection value 99.95 % 0.02 % 255 MPa 45 % 0.015mm Standard values ≥ 99.9 % 0.015-0.04 % ≥205MPa ≥40 % ≤0.040mm The appearance of the opened copper tube corrosion are shown in Fig. 1 and Fig. 2.
Fig. 1 shows the brass surface having a large number of green corrosion products.

In addition, a number of works are known [2, 8] which demonstrate that the appearance of meniscuses in the center of the craters is due to the perturbation of the surface liquid metal under the influence of high-voltage electric fields (generated by anode or cathode voltage drops) the force of surface pressure of the melted metal and that of the weight.
Further analysis of the lateral surface of Taylor type cones has demonstrated that during the process of solidification and constitution of solid material grains some asperities of nanometric dimensions are crystallized on their surface (Fig. 6).
The extraction of conic meniscuses through extensive oxidation of their surfaces was seen when the number of electric discharges increased.

The first number in the legends shows deformation temperature, the second part is the strain rate, and the last number is ln(Z) for the respective deformation condition.
Finally, it should be noted that Z is not the sole governing parameter in DRX kinetics since other parameters, e.g. initial grain size of the material, are also effective.

In the presence of a deoxidizing gas, the surface density of the negatively charged oxygen decreases, so the barrier height in the grain boundary is reduced.
The first and the second groups, indicated by number 1 and 2, correspond to sunflower and grape sheet oils, while the third, fourth and fifth indicated by number 3-5 correspond to mutton, lard and chicken fats, respectively.

By the end of 2009, the population of Ankang city has reached 26.606 million; the total area is 23,529 square kilometers, among which, cultivated land area reaches 199,000 hectares, 1,658 million hectares belong to forest ,and coverage rate is achieving 56.5 percent, the grain sowing area is 278,000 hectares, 884 ,600 tons of food production, and the net income of each farmer is 3313 yuan.
Poverty population is about 400, 000, of which the characteristics are large number, wide range, and deep level.
The number of poor households who moved away which have reached 1859 involving 7524 people; over 139 small watershed with 4621 square kilometers has been improved.

The common quality defects of construction projects are great in number and are mainly embodied in such three aspects as “crack, infiltration and leakage” and common quality defects of concrete include inadequate strength, honeycombs, pitting surface, holes, exposed reinforcing bar, lacking edge and angle and temperature cracking, etc.
For example, the grain diameter of gravels selected for grouting and the control of clay content of plaster sand have a significant influence on project quality and therefore, the correct selection of raw materials is one of the main measures to control the quality of concrete.
For example: 55 concrete columns in certain project have inadequate strength and when the problem is detected, steel hoops are adopted for reinforcement to cause the total number of floors to be reduced by two and the loss reaches RMB 1.2 million.

It is affected not only by the internal factors, such as the physical characteristics of the soil, grain composition, the density of filling, the permeability performance and the initial stress, but also by the external factors, such as earthquake magnitude, epicentral distance, vibration duration.
, （1） where is the initial shear stress; is an empirical parameter reflecting the pore pressure decreasing with , and its value is generally between 1.1～1.3; is the increment of equivalent number of cycles; is the liquefied number of cycles.

This is due to the fact that the higher surface area, the high concentration of crystal defects, such as dislocations, stacking faults, and vacancies, and the greater number of grain boundaries provide more nucleation sites available for hydride.
For a chemical reaction to proceed at a reasonable rate, there should exist an appreciable number of molecules with energy equal to or greater than the activation energy.