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Abstract: High-strength flowing concrete is made of large volume of gelled materials and high rate of sand, but low content of coarse aggregate and small grain diameter, which makes it easy to have a greater contraction, resulting in reduced strength and durability of concrete[4] .So the right amount of expansion admixture is needed to ensure that there is no shrinkage or micro-expansion of the concrete.
Table1-1 The cement clinker composition of Huaxin ordinary silicon 42.5 chemical composition (％) SiO2 Al2O3 Fe2O3 CaO MgO SO3 Loss 22.56 5.10 3.52 60.05 3.41 2.26 3.10 Table 1-2 　Physical and mechanical performance index of Huaxin 42.5 ordinary silicon cement name of samples result Normal consistency water consumption％ setting time rupture strength (MPa) compressive strength (MPa) Proportion (g/cm3) Initial set Final set Three days Twenty-eight days Three days Twenty-eight days national standard / ≮45min ≯10h ≥3.5 ≥6.5 ≥16.0 ≥42.5 / Results of observation 24.5 140min 4h10min 4.0 7.0 18.9 44.9 3.18 Table 1-3 List of cement species Number Name of manufacture factory Brand Varieties 1 Hubei Xinhua Cement Plant Fort Brand 42.5P.O Cement 2 Guangzhou Cement Plant Golden sheep Brand 42.5P.Ⅱ Cement 3 Cement Plant of Yao County, Xi’an Province Qin Ling Brand 42.5P.O Cement 4 Tianjin Cement Plant Camel Brand 42.5P.O Cement 5 Tianjin Building Materials Group Zheng Tong Brand
number The amount of gelled materials (kg/m3) Water (kg/m3) Share of additive in the total gelled materials (%) Sand (kg/m3) Limesone (kg/m3) cement Fly ash Silica fume Expansion admixture 1 435 83 / 32 163 CAN 1.50 688 1032 2 427 83 / 40 165 CAN 1.50 688 1032 3 455 35 / 40 165 CAN 1.50 692 1038 4 430 71 36 58 170 CAN 1.50 638 1041 5 428 60 / 60 170 CAN 1.50 688 1032 6 461 105 84 70 165 CAN 1.55 566 1003 7 496 70 84 70 165 CAN 1.55 566 1003 3.1 Concrete workability and mechanical properties The properties of the concrete mixture and the mechanical properties of concrete in different ages are shown in Table 3-1 [5].
Table 3-1 Performance test of the flowable high strength concrete number Initial concrete properties Concrete properties after 90min Compressive strength (MPa) Slump flow (cm) Time for flowing to 50cm(s) Time for funnel to flow down (s) Fill density (%) Slump flow (cm) Time for flowing to 50cm (s) Time for funnel to flow down (s) Fill density (%) f3 f7 f28 1 64×65 13.1 14.5 85.7 59×53 15.0 15.4 79.2 39.7 50.5 59.7 2 67×68 9.8 10.1 95.4 65×66 11.1 11.5 92.7 41.7 55.9 62.1 3 59×61 10.5 12.4 80.1 54×56 12.5 13.5 90.1 45.9 61.5 73.5 4 66×63 9.0 11.4 90.5 66×65 109 13.2 88.5 57.8 62.8 65.7 5 68×69 8.9 10.4 95.6 67×67 11.3 12.7 93.9 61.0 68.7 74.7 6 66×67 8.5 9.2 93.7 66×65 10.9 11.5 90.8 54.6 62.8 90.3 7 68×62 8.7 10.1 95.7 64×65 11.0 13.3 92.4 56.0 65.3 92.5 Note: ordinary portland cement 42.5 is adopted in group one to five, and ordinary portland cement 52.5 is adopted in group six to seven.
Table 3-2 The limited swelling rate of the high-strength fluid concrete Number 7d 14d 28d 60d 180d 1 0.017 0.019 -0.008 -0.021 -0.022 2 0.015 0.020 -0.006 -0.016 -0.017 3 0.016 0.018 -0.005 -0.017 -0.020 Note: The mixture ratio can be seen in Table 3-1 as 1,2,3.

The middle and lower reaches of the Yangtze River is an important base for producing grain, cotton and oil plants, one of the most rapidly developing areas economically in China.
Main Issues of Water Environment and Water ecology in the Middle and Lower Reaches of the Yangtze River The middle and lower reaches of the Yangtze River is an important base for producing grain, cotton and oil plants, also a region where the water resources is the most abundant in China.
A large number of sediment into Dongting Lake owing to the four rivers discharging a part of flood from the Jingjiang caused a ceaseless decrease of their inflow[2].
In the past decade or more, sewage discharge increases with the rapid economic development, water pollution in canals or lakes is difficult to control effectively because a large number of untreated industrial waste and sewage directly discharge into the freshwater system, furthermore, fertilizer and pesticides are used much in agricultural production.
However, remedial measures should be actively adopted in order to loss of grain caused by flood to the minimum.

A large number of microorganisms are capable of reducing ferric iron and are widely distributed in many environments [1, 2].
Biological iron reduction has been shown to occur with a number of oxidized or partially oxidized iron compounds such as magnetite and various Fe(III)oxyhydroxides.
The samples have an average grain size diameter of about 0.1 mm and the pH(s) were circumneutral with values around 7.5.
DNA copy numbers per g dry weight obtained with qPCR quantification of 16S rRNA genes of Bacteria, Archaea and Geobacteraceae.
Conclusions Both, Archaea and Bacteria are present in similar numbers in the nickel lateritic ore deposit.

Abstract: Study on the effect of liquefaction mechanism on the performance of ECC, adding rubber powder mesh size effect on the performance of ECC, respectively, to 40 mesh, 60 mesh, 80 mesh and 100 orders at the same content of rubber powder and 40 mesh in different dosage on ECC compressive strength, flexural toughness was analyzed, results show that: the use of the mechanism of liquefaction of mixing rubber powder in cement based materials, with the increase of ECC number increased ductility, at the same time reduce the compressive strength is larger, rubber powder content in 12%, the comprehensive effect is ideal.
Sand: the sand grain size is 0.22~0.37mm.
a) b) Figure 2.a) Compressive strength of G1~G4 b) Compressive strength of G1‘~G4‘ Conclusion 1) the liquefaction mechanism to adjust the ECC ratio, thus liquidity or cement matrix and reducing segregation, achieve high ductility cementitious matrix and multiple cracks and thus more easily. 2) rubber powder mixed with larger mesh size, compared to the number of small can more easily achieve ECC high ductility, but the maximum carrying capacity is greatly reduced, the compressive strength has greatly decreased; with the increase of rubber powder mesh, ECC corresponding improved ductility.

In the annealed specimen, relatively large particles of Fe16N2 were formed with low number density, while in the deformed specimens, dislocation substructures due to cold rolling were disappeared by ion-implantation and fine particles were densely formed.
Number density of the �" particles in (b), cold rolled with 90 %, is obviously higher than that in (a), annealed specimen.
On the other hand, in the annealed specimen, interstitial iron atoms firstly diffuse to sinks, such as surface and grain boundaries, remaining vacancies and nitrogen atoms.

A further increasement of Y content causes the grain columns with features of the zone T microstructure of Thornton's model[7] (Fig. 1 (c) and (d)).
The number of Cr deposited on substrates is not changed at a unit time, that is to say, the number of Al deposited on substrates increases.
During the sputtering process, the number of Al deposited on the substrates changed greatly at a unit time with increasing of Y contents in Al targets.
So the number of positive ions to Al targets at a unit time was a constant.
(2) The number of neutral particle increases above Al target containing Y when CrAlTiN layer is produced.

Introduction Air-suction seeder, is able to overcome many shortcomings of mechanical seeding device, has no strict requirements on seed geometric dimensions, easy to achieve single grain sowing, has the advantages of high operating speed and low rate of seed damage.The principle of air-suction in the precision seeder’s design has certain advantages, which is the main study direction of precision seeder [1~3].
The first chain reciprocal screw: The second chain reciprocal screw: The third chain reciprocal screw:, the chain reciprocal screw does not exist. 3.3 Calculation of parallel mechanism’s DOF Come to conclusion by the above calculation results: the number of common constraints λ=0, and the mechanism's order d=6-λ=6, redundant constraints is the constraints in the removal of common constraints, when removing the common constraints, the left t constraints constitute a k-screw, the redundant constraints: V=t-k=3-3=0, there are 0 redundant constraints.
DOF of the parallel mechanism: In which: M—the number of DOF, d—the order of the mechanism (d=6-λ), λ—the number of common constraints, n—the number of components including the rack, g—the number kinematics pair, fi—relative DOF number of the i-th kinematics pair,v is the number of redundant constraints, z is the number of local DOF. 3.4 Motion characteristics of parallel mechanism’s moving platform Parallel mechanism’s moving platform constraint screw matrix as follows: Get moving platform free kinematics screw as follows: Free movement of the moving platform is getting along z-axis, revolving around x-axis parallel and revolving around BC axis, the moving platform has three DOF and can meet the requirements of horizontal adjustment.

Fig. 1 Soft sphere contact model Fig. 2 Simulation device Simulation experiment Dry sand filling process is related to vibration parameters, shape of flask, buried depth and a number of factors, this article mainly uses three dimensional DEM to simulate dry sand filling process, and by investigating the number of dry sand filling direction to study the vibration effecting on dry sand filling movement.
Afterwards count the sand number of the key filling parts for getting the number of dry sand filling curve under the different directions vibration.
Fig. 4 Dry sand filling number curve Fig. 4 stands for the dry sand filling number curve of filling cavity Ⅰ under the different directions vibration, where X, Y, and Z denote respectively flask along the X, Y, Z one-way vibration, XY, XZ, YZ along the X, Y or X, Z or Y and Z directions vibration, XYZ along the X, Y, Z three directions vibration at the same time.
Refer to the 1DOF vibration, filling time is longer, limited fill number is less, which can't achieve full filling.
(3) Compared the three dimensional DEM with the traditional dynamics method, the former fully considers the interaction between the sand grains, greatly improves the accuracy of numerical simulation, which provides a new path and method for further research and perfect EPC method dry sand filling theory.

Tetrahedral structure of WO4 that appear at wave number of 906 cm-1 and 955 cm-1 in the FTIR spectroscopy confirmed.
Nanoscale Al2O3 exhibits two important features that aiding ionic conductivity in electrolyte such as large specific surface areas and grains covered with various Lewis acidic group [8].
Other bands observed in the wave number specified in Fig. 5 are attributed to W-O and O-W-O vibrations.

And Grid is able to manage a large number of heterogeneous resources of geographically and organizationally distributed.
With the analysis of the runtime performance of GSRI, it is shown that despite the latency created by the transmission through WAN, the GSRI may support the coarse-grained large-scare distributed simulation applications.