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A good number of laboratory and case studies in the literature showed that an in-depth PMA can achieve deep plugging and with good stability is needed to improve the flooding to the oil layers [2,3].
The sand pack (L = 50 cm, D = 2.5 cm) is filled with quartz sand with grain size from 40 to 60 meshes.
Table 1 The plugging capacity of PMA for different permeability cores Number Permeability before plugging (×10-3mm2) Composition Gradient of breakthrough pressure (MPa/m) Permeability after plugging (×10-3mm2) Shutoff efficiency(%) Shutoff efficiency after being flushed(%) 1 216.6 1000ppm PMA 29.6 10.3 95.2 95.0 2 1663 6 1046.0 37.1 35.8 3 4 198.2 1864 3000ppm PMA 41.7 11.5 0.9 165.8 99.5 91.1 96.3 90.2 Oil displacement property of PMA.
Fig. 2 Variation of the flow rate with injection time before and after profile modification Table 2 The double tube oil displacement results of the PMA Number Tube mode PV (cm3) Oil saturation (%) Water flooding recovery(%) Recovery enhanced by PMA(%) Total recovery(%) 5 High 77.5 67.1 54.8 12.5 67.4 6 Low 73.0 58.9 58.5 4.65 63.2 From Fig. 2, it can be seen that the novel PMA, with high capacity of selective injection, and good compatibility with rock pores, can modify the distribution of the streamline field and pressure field, change flow direction of injected water, enlarge swept volume, and improve water displacement efficiency.

The grain size is about 10~20μm. 20μm 100μm a b Fig.1.
At second day, the number of bacterial was the largest, the metabolic products were the most and the biofilm was thick.
Two peak maxima changed to one from fifth day, this is because the number of bacterial decreased slightly and the biofilm became thinner with time.
The diameters of impedance loops fluctuated and the number of maxima varied between one and two.

The elongation number of A´B´ in the direction of y: The horizontal distances from A´,B´ to o respectively are as follow: The elongation number in the direction of z is: The elongation number of AB is approximately expressed: So the elongation percentage of AB is: Criterion of LEFP bifurcate fracture The oxygen-free copper crystal grain size of shaped charge liner has turned refiner under explosion loading and its tensile strength and fracture elongation percentage are increased[5], so there is the maximum dynamic elongation percentage , if The bifurcate fracture will arise, which leads to the formation of the separating craters on the target.

New polishing technology is developed as for large numbers of new type precision integrated photoelectron systems, with good performance.
After Journal Title and Volume Number (to be inserted by the publisher) 645 that, taking down these wafers and damage layer on the wafers were measured again.
By changing the proportion of each ingredient, the perfect flow and suspended character are gained, and the wafers will not to be defiled by remnants grains.
Furthermore, the material particles were removed when the abrasives particles in the decade’s nanometer level are used to polish the LN wafer, it cannot be explained by these polishing Journal Title and Volume Number (to be inserted by the publisher) 647 mechanisms macroscopically.

Introduction Application of precise contemporary X-ray methods by study of shell tubes from Zr-based alloys permitted to reveal a number of structure features, able to quicken diffusion of oxygen into the matrix.
Mean values of coefficients αc and αa at 350oC, found for a number of literature data [6], are equal to 5.5 deg-1 and 8.8 deg-1, respectively.
It is seen in Fig. 2-b, that under the influence of tangential macrostresses lamellar hydride particles take up radial positions, perpendicular to outward surface of tube, and coincide apparently with grain boundaries, having analogous orientations and being ways of active oxygen diffusion under operation of tangential macrostrsses.
Thermal expansion of different layers of shell tube by its heating up to 350oC Sample number Depth of layer, t, µm fT αT 10-6, deg εТ, 10-3 εТin/ εТout 1 250 0,37 6,721 2,2179 1,005 600 0,38 6,724 2,2288 2 240 0,36 6,688 2,2070 1,025 620 0,41 6,853 2,2615 When taking into account values εТin/εТout, presented in the last column, it becomes understandable, that by control of production the first tube was accepted as satisfying to technical conditions, whereas the second tube was rejected as spoilt.

The experimental results and discussion 2.1 Determination of debris recovery Choose water and well completion fluid system, add 50 grams of natural debris, the grain size of 40 ~ 60 mesh, under 60℃, scroll after 24 h, recycling with the sieve of 100 mesh, drying, weighing, notes for the m1, calculate recovery rate R1, the bigger R1 is, the smaller the cuttings dispersion degree is, the better the stabilization effect is.
Table 4 Determination of completion fluid corrosion rate Specimen number Surface area 10-4m2 Quality g Quality of corrosion g Corrosion rate g/m2·h 1# 20.5 20.2469 20.2357 0.076 2# 21.4 20.7862 20.7740 0.079 average 20.9 20.5166 20.5049 0.077 Seen from the table, the average corrosion rate is 0.077 g/m2·h, less than the enterprise standard of Daqing oilfield limited liability company, the standard is 0.100 g/m2·h. 2.4 Completion fluid for the influence of different permeability cores Choose three different permeability of natural cores respectively into three core grippers, with 2.0% KCl solution measured core permeability , denoted by K1, injected completion fluid, after 24 hours measured core permeability, denoted as K2, Calculated Damage core rate, the experimental data are shown in Table 5.
Table 5 The influence of completion fluid on core permeability Core number K1 10-3μm2 K2 10-3μm2 Damage rate ％ 1-4 94.5 82.4 12.8 1-7 131.2 115.2 12.2 1-8 186.3 166.7 10.5 From the table can be shown, to the cores of different permeability and injection after completion fluid, permeability reduction, the higher the permeability of the core, completion fluid of core damage degree of the lighter.
Table 6 The influence of completion fluid immersion time on core permeability Core number K1 10-3μm2 Immersion time h K2 10-3μm2 Damage rate ％ 1-9 78.9 4 72.3 8.4 2-6 71.6 12 63.6 11.2 2-11 82.9 48 71.0 14.3 2-13 77.0 120 65.7 14.7 From the table can be shown: For the four similar permeability cores, with the extension of completion fluid immersion time, the core of the damage degree would increase, initial core damage is faster, the increase amplitude of the damage rate will slow down after 48 hours.

The literature analysis shows that materials based on aluminum effectively strengthened when bringing them to sub-ultrafine-grained or nanostructural level [1-6], but the properties of aluminum alloys obtained using nanomaterials are insufficiently studied.
When reducing the carbon number of the liquid phase will increase, and aluminum to decrease.
The samples were prepared from aluminum powders with a particle size of the main fraction is 5-100 μm or crushed chips alloy AK9 and number of nanocarbon materials in the ratio of Al - 10 mass. % C in the original mixture.
Number of input ligatures in aluminum melt was calculated from the condition 1 wt.% carbon composite.

Table 1 Chemical composition of Ti-6Al-4V Element Ti Al V Fe C N H O Wt % Balanced 6.17 4.23 0.15 0.03 0.02 0.001 0.16 Table 2 Mechanical properties Material σy [Mpa] σb [Mpa] E [Gpa] Ti-6Al-4V 886.2 949.0 115.2 The USDR parameters adopted for processing including spindle speed, feeding rate, static force, ultrasonic vibration amplitude and repeated processing numbers were 100 r/min, 10 mm/min, 720 N, 16 μm, 50 times, respectively.
Grains in deformable layer are extruded and elongated.
During later cyclic loading the residual stresses decrease linearly vs. the logarithm of the number of cycles.
While at higher strain amplitudes, residual stress significantly decresed as the number of fatigue cycles increased.

Introduction In order to increase crop production ,when people grow they use a large number of pesticides and fertilizers, but it is neither environmental protection nor safe.So how can do both productive and reduce the side effects become a hot research topic .The experiment using high voltage electrostatic field to affect barley seed, discuss their effects on seed germination.The process using physical method without adverse effects and can achieve the purpose of crop productive, aims to further promote high voltage technology in the practical application of this field.
The experimental materials and method Barley seed (Liao Ning 5) is bought from Jilin province Runhe seed industry co., LTD.Fresh, without skin damage seeds were used in experiments.Seeds were divided into 7 groups, each group of 200 grains, placed in a petri dish.
Test results By comparing the experimental data，the number of seed germination, germination potential, germination index, vigor index of seed under 3.5 kV and 5 kV voltage are higher than other experimental group, the effect is significantly higher than the control group.Thus the high-voltage electrostatic field can promote the growth of barley seed, but the voltage is not the bigger the better, but the medium voltage .
Lead to a large number of ions through the membrane , thereby increasing the permeability of cell membrane, maybe this could explain the experimental results of this paper.

There are a number of measurement methods: mechanical release method (drilling method, ring core method, cut strip method, etc) and non-destruction measurement (X-ray diffraction, neutron diffraction, etc), X-ray diffraction analysis method which has no damage to the samples during the process of test is commonly used and it can be field measured [1-4].
The specific calculations are as follows [8]: (1) where , , is the number of direction, is the related coefficient.
Secondly, if the relation between and is no longer following the linear relationship, such as Fig. 2(c) shows, may be mainly caused by existed texture or coarse grains besides the accidental errors.
Table 3 Statistical analysis of the residual stress error Serial number Interval Group data Frequency 1 [14.5,16.0) 15.25 2 2 [16.0,17.5) 16.75 8 3 [17.5,19.0) 18.25 11 4 [19.0,20.5) 19.75 16 5 [20.5,22.0) 21.25 8 6 [22.0,23.5) 22.75 3 7 [23.5,25.0) 24.25 1 8 [25.0,26.5) 25.75 1 Fig. 4 Residual stress error square diagram (5) Because the parameters and of the given normal distribution were unknown, and should be estimated by maximum likelihood value method firstly