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Hence, the mechanical properties of rock mass, especially after the failure, still need to be further researched.
The failure and falling of underground rock mass are extremely complicated affected by anisotropy, existence of a large number of joints and various kinds of weak planes, and groundwater, ground stress and mining stress in the rockmass.
There are a lot of factors influencing strength of rock mass, such as the strength of the rock, mining operation, weakness plane, groundwater, certain error of calculating parameter of the rock mass, so that calculation methods of the stability of the rock mass often cause a large error, especially for numerical method used in mining engineering, which can be regarded as reference of project design and construction, but the really reliable method is based on the classification of the rock mass and other comprehensive evaluation indexes Roof falling Block theory is a kind of very good idea, but it is only useful an ideal condition.
The position of slag Mining range mined-out area Overall investigations on joint distribution in roof rock mass, allowable exposing area, formation of rock fall and related mechanical characteristics are carried out based on above mentioned theories.
The factors influencing stability of the rock mass are very complicated.

Sr-doped CaMnO3 materials have wide applications due to their thermal and electrical properties.
These efforts give significant effects on the properties of perovskite CaMnO3 based materials such as their thermal, electrical, and structural properties [1–27].
Longo, “Effect of pressure on the magnetic properties of Ca1-xSr xMnO3,” J.
Krstić, “Nanopowders properties and sintering of CaMnO3 solid solutions,” J.
Noudem, “Texture, mechanical and thermoelectric properties of Ca3Co4O9 ceramics,” J.

In the manufacturing process of the SiCp/Al alloy composite, an interface region with different physical properties or chemical properties will formed due to the physical or chemical reactions between the particles and the matrix.
The mechanical performance of the interface has important influence on that of the composite material.
The existed studies have shown that the interfacial property is a key factor which must be considered in the performance studies of the composites[1-3].
With the cohesive zone model, the mechanical properties of the interface layer such as strength, toughness, modulus can be reflected by choice of appropriate parameters[10].
Interfacial effects on mechanical behaviors of short fiber reinforced metal matrix composite.

Recent research results showed that the addition of non-metallic second phase particles such as oxides, borides and carbides could remarkably improve mechanical properties and wear resistance of metal matrix composites [1-4].
The wear of the composites was mainly affected by mechanical wear when the electrical current is low.
However, with the increase of the applied load, the mechanical wear of the composites increased according to Archard’s wear equation.
There could be an optimized load for a certain application in high speed sliding electrical contact because load was a factor related to both the electrical heating, frictional heat and abrasive wear.
Paulmier et al. [10] indicated that the passage of electrical current favors oxidation by increasing the surface temperature, and modified the mechanical properties of the oxides and substrate.

This translation agency’s installation is complicated, energy consumption, easy to wear, easy to affect accuracy.
A reasonable choice of wearing material Embedded PLC based control milling machine for the study, studied six different carbon and silicon content of the steel milling machine hardness, impact toughness , tensile strength, elongation and reduction of area , and analyze the friction and wear properties .
Author: Haiying Zhang, male, Birthday：1968.12, professor, Mechanical engineering teaching and researching Address: College of Electrical and Mechanical, DongGuan Polytechnic ,No.3 University Road ,Songshan Lake Sci.
Mechanical design [M] Beijing: Higher Education Press, 2005
Austempering temperature on the influence of microstructure and properties of low alloy wear-resistant steel [J].

Secondly, the windings mechanical property decreases.
However, the results of the frequency response method may be affected by electric field and magnetic field, measuring length, core remanent and other uncertain factors in the application[6-7].
Test data analysis The random variable which is affected by a large number of independent and uniform actions subjects to the normal distribution by the mathematical statistics theory.

At present, various types of growth factors have been reported to affect the ethnogenesis of ASCs.
During the tendon healing process, various types of growth factors such as Transforming growth factor-β (TGF-β), insulin-like growth factors I and II (IGF-I and II), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) work synergistically in the process [8,9].
The Roles of Growth Factors in Tendon and Ligament Healing.
Characterization of mechanical and biochemical properties of developing embryonic tendon.
Temporal expression of growth factors and matrix molecules in healing tendon lesions.

Its structure, morphology and properties were characterized by Ubbelohde viscometer, Fourier transform infrared spectroscopy (FT-IR), Differential scanning calorimetry (DSC), polarized optical microscopy (POM) with a hot stage, and wide-angle X-ray diffraction (WAXD).
Among main chain thermotropic liquid crystalline polymers, wholly aromatic thermotropic polyesters are particularly attractive, which have received considerable attention due to their convenient use temperatures, excellent chemical resistance, relatively high glass transition temperature (Tg) as well as their excellent processing and mechanical properties[2].
C O O CH2 O O n C O O C O C O In addition, the backbone flexibility is another important factor.
Intrinsic viscosity and thermal properties of PHBT, PHDT and PHET Structure ηinh /(dL/g) Tm/(℃) ∆Hm/(J/g) Yield/(%) PHET PHBT 0.2103 0.0881 177.5 224.1 15.31 29.33 85 90 PHDT 0.1500 183.2 17.89 87 The typical infrared spectrum of PHBT, PHDT, and PHET are shown in Fig. 1.
Particularly, the d value of PHET calculated from the peak B was quite different from that of PHBT and PHDT, suggesting that the introduction of oxymethacryloyl group can significantly affect the crystalline degree.

The obtained results can support the design of coated tools with improved properties at interrupted cutting operations by understanding the role of thermal cycling on the stresses of Ti(C,N) coatings. 1.
Since Ti(C,N) exhibits a quasi-isotropic mechanical response, ψ* is approximately the same (34.5°) for all lattice directions.
Thus, in order to obtain more representative stress values, the stress determination was accomplished by a weighted averaging of the sin2ψ curves from the diffraction lines using their corresponding multiplicity factors.
These preliminary results may indicate that the formation of the oxide layer could affect the stress intensity of the TiCN layer at different temperature levels.
Bhat, Review of CVD TiN coatings for wear-resistant applications: deposition processes, properties and performance, Surf.

Introduction Dynamic fracture and dynamic shear localization (or adiabatic shear banding) are the two major failure modes of materials subjected to high-rate mechanical loading [1].
Many experimental efforts have been reported on the determination of DFT and dynamic fracture properties of a variety of materials [6-12], and a number of theoretical models and criteria for dynamic fracture and shear localization have been suggested [13-16] up to now.
In this paper, dynamic fracture properties in both Mode I and Mode II of two high strength steels, 40Cr and 30CrMnSiNi2A, are investigated with a combined experimental-numerical method.
Temporal evolution of the dynamic stress intensity factor (DSIF) of each specimen was calculated and then the DFT was evaluated according to the fracture initiation time at different loading rates.
Materials and experimental procedure The chemical composition of the steels for investigation is given in Table 1, and the mechanical properties are shown in Table 2.