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When the main structure this material was attached to produces some normal deformation, such as shrinkage, creep, swelling and so on, rigid polyurethane foam would gradually soften and release stress layer by layer to prevent the cracking or falling off.
On another hand, the porosity structure of polyurethane material is stable as there are closed interspaces in interior , not mutually connected.
The construction of polyurethane materials could be carried out on most of the buildings, especially on the building structure node and other complex parts, such as bay windows, skylight, staircase, pipeline coatings and so on.
In addition, because of its hydrophilic molecular structure and unique closed t pore structure, the rigid polyurethane foam was also used widely in the noise reduction and seismic engineering projects.
References [1] Zhu Yimin and LiuYijun: Rigid Polyurethane Foam（3rd Edition）, Chemistry and Industry Press，Beijng, 2004 [2] Yan Ge: The Analysis of the Application of Rigid Polyurethane Foam in the Roadbed(2002)

Introduction AZ31 alloy is the most widely used wrought magnesium alloy, but its plastic deformation property is relatively poor due to its hexagonal close-packed (hcp) crystal structure.
Fig. 2(a), (b), and (c) show the edge, 1/2 radius, and central structures respectively of the alloy with effect of Al4C3 grain refiner after holding time of 60 min at 680 oC.
Fig. 2(d), (e), and (f) show the edge, 1/2 radius, and central structures respectively of the alloy with co-effects of Al4C3 grain refiner and low-frequency electromagnetic stirring after holding time of 60 min at 680 oC.
Motegi, Grain refining mechanism and casting structure of Mg-Zr alloy, J.
Chen, The application of the discrete variational method in the density functional theory to chemistry and materials physics, Science Press, Beijing, 1998

Introduction Steady high magnetic field is an extreme environment that is a very important and fundamental tool for researches of many subjects including physics, chemistry, biology, medicine, and so on[1].
Design and Realization of SPS for WM of SHMFF Structure of SPS.
The structure of PAC’s software is shown as Fig. 4.
Fig. 4 Structure of Software of PAC Fig. 5 Flow chart of judging fault of WM Simulation System.
Fig. 7 Structure of SPS Fig. 8 Snapshot of MSI when testing SPS Conclusion WM of SHMFF requires very high electric current to generate steady high magnetic field.

Transmission electron microscopy (TEM) is the one appropriate technique which has characterized the physical properties of materials and the most useful methods to clarify the structure in materials.
In order to be able to accurately and robustly quantify material structures, we must obtain a statistically high number of showing images of the appropriate material structures.
The next step is the application of the image processing method in order to extract meaningful structure from the acquired images.
TEM image reveals the detailed examination of the shape, size and structure of material particles.
[10] IUPAC: Compendium of Chemical Terminology Gold Book (International Union of Pure and Applied Chemistry(IUPAC), 2012)

These received nanoparticles were investigated using different methods to characterize their morphology and structure.
Fig.1c shows the typical structure after the nano powders, revealing the nucleated nano-crystalline domains within the powders.
A broad range between 100°C and 450°C contributes to the loss of lattice water from the apatite structure.
When starting HA enters the high temperature plasma region, the surface water is released from apatite structure.
Alves; Journal of physics and chemistry of solids, 62(2001), p1251-1255.

Greshnyakov, Classification and structure of silicon carbide phases, Physics of the Solid State. 54 (2) (2012) 433-440
Gomes de Mesquita, Refinement of the crystal structure of SiC type 6H, Acta Crystallographica. 2 (4) (1967) 610-617
Nanoscale materials in chemistry, New York: Wiley-Interscience, 2001
Andrievski, Nano-sized silicon carbide: synthesis, structure and properties, Russian Chemical Reviews. 78 (9) (2009) 821
Patent 2,431,947. (2011) [21] Sivkov, A., et al., Plasma dynamic synthesis and obtaining ultradispersed zinc oxide with single-crystalline particle structure, Advanced Powder Technology, 27(4) (2016) 1506-1513

Samples 1 and 2 exhibit well-crystallized structures.
Samples 3-5 exhibit porous structure; hence their surface area is much larger (see Table 1).
Xu, Yo Zheng, Structure and properties of Fe3O4 films grown on ZnO template via metal organic chemical vapor deposition.
Gao, Facile synthesis, structure and visible light photocatalytic activityof recyclable ZnFe2O4/TiO2, Applied Surface Science. 319 (2014) 83-89
Shabelskaya, Synthesis and Properties of Binary Spinels in a NiO-CuO-Fe2O3-Cr2O3 System, Glass Physics and Chemistry. 43 (2017), Is. 1, 240-245

Normalised steel will consist of fine ferrite or cementite with grains of pearlite but hardened and tempered steel will be expected to have a bainitic structure or tempered martensite.
This may be attributed to the variations in alloy chemistry.
However, Fig. 2(b) show the presence of fine equiaxed structure.
Fig.2 (c, d) show the carbides and fine equi-axed structure in the Q/T condition, see Fig.2 (c) and bainitic structure in the Q/T condition, see Fig.2(d).
A mixture of bainite and martensite structure are shown in the heat treated and tempered conditions.

The geological structure of the region is complicated, the part of roadway along the tunneling direction of two roadway in the middle of the fault, the gap are 7.0m and 5.6m, the sphere of influence up to 210m, the seam roof were squeezed and stretched repeatedly, the integrity of the coal roof was damaged greatly, and leading to great in-situ stress.
The slurry was consolidated to the criss-cross fractures of surrounding rock by squeezing or penetration, and form a network skeleton structure.
Although the compressive strength of the polymer chemistry materials of network skeleton structure than the surrounding rock is not necessarily high, but this consolidation body has good toughness and adhesion.
By grouting, the internal friction angle of roadway surrounding rock has changed, the strength of the surrounding rock is improved, the carrying capacity of the surrounding rock itself is used completely, roadway surface has a smaller deformation, the coupling of surrounding rock and retaining structure are achieved in strength, stiffness and deformation, a good reinforcement effect is achieved and provide a reference for the similar roadway.
Traditional strengthening ways have low efficiency, large labor intensity and seriously affect the safety of production, the grouting technology is used in broken roof, the rock’s loose structure is changed timely, the overall strength of the coal and rock are improved, the construction schedule is improved greatly, thus the normal convergence of mining of the work face is ensured, technical and economic and social benefits are remarkable.

Presuppositions Because the thermal deformation calculation of a dry gas seal is very complicated, so this article mainly discusses the emperature field and thermal structure coupling deformation under stable states.
Thermal Analysis The structure of the first stage dry gas seal in the synthesis gas compressor is shown in Fig. 1.
Because the structures of the seal rings and boundary conditions have axial symmetry property, so the problem can be simplified as a problem of axial symmetry stable thermal conduction, its heat conduction equation [5]
(11) Constraint Conditions Exact and reasonable boundary constraint conditions are the basic of resolving the heat-structure coupling deformation, therefore, sealing ring structure must be analyzed to acquire restriction conditions, so as to simply and resolve the problem.
Averne: Fundamentals of Heat and Mass Transfer (Publishing House of Chemistry Industry, Beijing 2007) ,in Chinese