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Introduction For slice mining of thick coal seams in the early time, mining and management is relatively backward, resulting in a large number of coal resources residue.[1]We should recycle the resources, but its occurrence conditions are relatively complex.[2]especially early digging generating irregualr goaf resulting in certain limitations in on-site detection.
Most of the coal seam roof are siltstones and mudstones, its old roof is a layer of fine-grained sandstones.
Thickness(m) Distance(m) Structure Roof lithology Floor lithology Stability level Admissibility MIN-MAX AVE MIN-MAX AVE MIN-MAX number of interlayer 2 4.53-8.65 7.06 0.55-3.30 2.24 0-5 Mudstone/Siltstone Siltstone/Mudstone/Fine sandstone Stable ALL 3 0.55-1.63 0.91 0-2 Mudstone/Siltstone Siltstone/Mudstone Stable ALMOST Tab.2 Characteristics of Coal seam Roof and Floor in Maozequ Mine Coal seam No.

However, the increasing of Al addition will restrict grains growth.
Acknowledgment The authors gratefully acknowledge the foundation by the National Natural Science Foundation of China (NSFC) with the project number 50775045, Guangdong Natural Science Foundation for Team Project and the Project of Dongguan Science & Technology with the project number 200701109.

Then a large number of primary αphases dissolved and a few had been kept after the flat billets were secondary forged and rapidly cooled.
In addition, the fast cooling process also caused the alloy grains to fail to grow, So the plasticity is better than that of the show cooling process.
8 ≥ 20 ≥ 635 ≥ 50 ≥24 ≥855 930/ 1130 ≥ 8 ≥ 25 ≥ 635 ≥ 50 ≥ 32 Note: persistent temperature 500℃, stress 470MPa Fig. 3 Transverse strength at room temperature Fig. 4 Longitudinal strength at room temperature As mentioned above, although the comprehensive properties of the flat billets produced by the four processes all meet the standard requirements, the mechanical properties of the blank forged by the 1-4 process are the best (see table 2), and the microstructure also meets the blank requirements of the forging.Since the final forging is used as a bearing part, the higher the strength, the better, so in conclusion, 1-4 process is selected as the best process for producing blank for frame forging. 3 Conclusion It’s an excellent thermal process for TA15 titanium alloy slab that the first forging temperature is T1 and the secondary forging temperature is T2 with rapid cooling rate after thermal deformation.The flat billets will have 10% primary α phases and a large number

The phenomenon of "bottom tearing scour" has aroused great concern for water workers at domestic and foreign and obtained a large number of research results.
The sampling positions table Number Name of the sampling cross-section Sampling position coordinates or engineering positions E N Ⅰ The upper layer of Yellow River left bank No. 67 sedimentation cross-section Dashizui engineering Ⅱ The lower layer of Yellow River left bank No. 67 sedimentation cross-section Dashizui engineering Ⅲ Yumengko No. 68 sedimentation cross-section of Yellow River left bank 110°36′06.9″ 35°39′30.4″ Ⅳ Yumengko No. 68 sedimentation cross-section of Yellow River right bank 110°35′40.5″ 35°38′27.4″ Ⅴ Lang dian engineering 4 No. dam of Yellow River left bank sedimentation cross-section 110°21′34.5″ 35°05′47.1″ Ⅵ The 50 cross-section of Yellow River right bank sedimentation cross-section Hua yuang engineering opposite the new beach The soil particle-size analysis experiment：In the experiment, using sieve analysis to select part of the particle size greater than 0.075mm; using  hydrometer method to select part of particles size less than 0.075mm, using sodium
Moisture content as the abscissa, cone sink depth as the vertical axis, draws a relationship curve in the double logarithmic graph paper, getting respectively fine-grained soil liquid limit, plastic limit, by calculated the plasticity index in turn divided into the soil type.

The distributions of iron loss and magnetic flux inside a magnetic plate and grain-oriented silicon steel lamination are certainly not uniform; especially the eddy current loss induced by the normal magnetic flux is concentrated in a thin surface layer.
The number of turns of each exciting coil is 300.
We can be calculated by (4) (4) Where NE and V (e) denote the total number of elements in non magnetic copper plate and the volume of element e, respectively.

But the double bond and aromatic ring in these substances can react with the acid catalyst, which can reduce the molecular weight of resin and increase the number of carboxyl group [4].
Materials and Methods Wood specimens were cut from first grade flat-grained sapwood of P. sylvestris with the similar color.
Specimens were numbered and measured firstly.

Lines were drawn along the grain direction of each flake (Figure 1).
Where, θ is the average absolute alignment angle of each board; θi is the measured angle over the range of -90 o to 90o ; and n is the total number of flakes.
The numbers in the graph represent different tested panels.

The interplanar spacing {hkl}, average for the reflecting grains volume, can be obtained from the measured diffraction peak position (2θ{hkl}) using Bragg law.
In the g-sin2 ψ geometry, only the φ angle (rotation around normal to the sample surface) can be chosen arbitrarily, but the ψ angle (defined in Fig. 1) depends on the (hkl) reflections and the constant incidence angle α , i.e.: t Ψ2 Ψ1 2θ1 Z Scattering vector (h2k2l2 ) Scattering vector (h1k1l1 ) α α 2θ2 αθψ −= }{}{ hkl hkl (1) Consequently, the possible values of ψ{hkl} angles are limited to the number of (hkl) reflections used in the experiment.
The used procedure is based on minimizing of the merit function called 2 χ , which is defined as: 2 �1n n cal {hkl}nn exp {hkl}nn 2 a a M� 1 = ∑=         ><−>< − δ ψφ ψφ χ ,( ,( (3) where exp {hkl}nna >< ψφ ,( and a cal {hkl}nn > < ψφ ,( are the experimental and calculated lattice parameters, nδ is the measurement error (standard deviation) of >)a( < hkl}{,ψφ for the n-th measurement, � and M are the number of measured points and fitting parameters, respectively.

In this paper, the experimental study for IDFPDA is to study the effect on vibration attenuation of IDFPDA, by changing the diameter and the number of impactors, and the particle materials.
In order to compare easily, the number of different diameter impactors above were 1, 8, 64 and 1000 with the equivalent mass.
Found that the inner diameter of damper was 12mm, and after added 10mm diameter steel ball, the clearances became 2mm same as the diameter of quartz grain.

Introduction In order to effectively address the Loess Plateau in Northwest China's drought and water shortage, drinking water problems, large areas of arable land suitable for long-term issues such as waste, to improve the lives of these areas, the ecological environment, prevent the desert southward, the state has in Gansu, Ningxia, Shaanxi and other regions the construction of a number of water and irrigation water, most of these projects play a huge economic, social and ecological benefits, and has become a drought in western China turn over the people in the region works and rich project, of which King Taechon electricity in Gansu Province to irrigation project (hereinafter referred to Jingdian project) and irrigation in Ningxia Guhai is a typical representative of [1].
Table 1 The analysis result of the groundwater quality [mg/L] Sampling locations Cl- SO42- Mg2+ Salinity Jingdian a second phase of the total dry ducts pumping station 1224.6 2527.6 127.8 5869 Second phase of the total dry Jingdian after four pumping stations and ducts 955.9 1029.7 76.4 3106 Second phase of the total dry Jingdian after five pumping stations and ducts 2101.9 1810.6 119.3 6280 Ningxia Guhai total of five pumping stations before the pools dry 889.8 921.6 79.8 2960 Ningxia Guhai 9 total dry pit pump stations after the tube 1896.7 2601.6 70.6 9516 The study showed that [2], as a result of hardening of cement hydration in the body there are a large number of unstable or meta-stable state of the material such as water and calcium aluminate, calcium hydroxide, when the erosion of media outside the SO42-, Cl-invasive cement plasma rock and role of these substances in the pores of cement in the local weak form partial double salt (ettringite, hydrated calcium aluminate, etc
When the humidity changes, the occurrence of grain size change with the expansion of concrete damage; for other reasons Concrete structures within the pore structure and porosity of the building is also an important anti-erosion factors, the general erosion of media through the pores and cracks within the concrete invasive.