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The mechanical properties of ultra-fine grained and nanocrystalline materials, therefore, can be severely affected by the dynamic behavior of grain boundaries.
Coupling between grain boundary migration and produced shear is characterized by the factor determined as β=γ=s/d.
Moreover, the experimental results have verified the prediction of the model by Cahn et al. [14,15] that the tangent rule for calculation of the coupling factor β retains its validity over the entire misorientation range including the high angle regime: as depicted in Fig. 2a, the values of the coupling factor calculated according to the model are in excellent agreement with the values obtained in the experiment.
(a) Measured (points) and calculated (lines) coupling factors β and (b) activation enthalpy H of stress driven migration vs. misorientation angle θ for symmetrical <100> tilt grain boundaries [28].
Contrary to this prediction, the experiments with <100> tilt boundaries [31] as well as measurements on bicrystals with <111> tilt boundaries [32], showed that the asymmetrical tilt boundaries can move under an applied stress and produce a shear, although the obtained coupling factors distinctly deviated from the coupling factor calculated according to the tangent rule.

In fact, the change in microstructure of concrete is fundamental cause for the changes of mechanical properties.
Lima and RCA[20] thought that the concrete after fire changed its microstructure and macro mechanical properties such as compressive strength.
Ucarkosar, B., Yuzer, N. and Kabay,N.[35]in Yildiz Technical University think that when concrete exposed to high temperature, its physical and mechanical properties will change.
And there is no further study on the relationships among comprehensive conditions , concrete microstructure and macroscopic mechanical properties
Mechanical properties and microstructure of high strength concrete containing polypropylene fibres exposed to temperatures up to 200 °C Cement and Concrete Research, 2005, v35, n11, p2192-2198

Ogunmola and Gaius Nzebuka Department of Mechanical Engineering, University of Lagos, Akoka, Lagos, Nigeria.
In this study, heat transfer in a longitudinal rectangular fin with temperature-dependent thermal properties and internal heat generation has been analyzed using finite volume method.
Therefore, while analyzing the fin, effects of the temperature-dependent thermal properties must be taken into consideration.
Hence, in this work, finite volume method was applied to analyze heat transfer in a longitudinal rectangular fin with temperature-dependent thermal properties and internal heat generation. 2.
Analytical Solutions for Steady Heat Transfer in Longitudinal Fins with Temperature-Dependent Properties, Mathematical Problems in Engineering, vol. 2013, pp. 14 pages

This study utilized mechanical calculation method and finite element method ABAQUS software to analyze the mechanical response of different flexible pavement material combinations on steel deck.
Construction of Steel Deck Pavement Structure Three-Dimensional Finite Element Model This section described the geometric shape, wheel load, and boundary conditions of the model, as well as the material properties of each course of pavement according to the construction procedure of finite element model.
This study intended to make the most of the geometric symmetry property of structure and the symmetry property of load, and reduce the computer computing time and memory consumption.
Material properties.
The flexible paving material properties of the steel deck in this study are listed in Table 1, using the test data of modulus of resilience of Pan [4] and Chang Liao [5], at temperatures of 25 and 40, respectively.

Based on experimental study of physical and mechanical properties of main rocks of the roof and floor of the under-group coal seams, and the application of "Up Three Zone" Theory of coal seam roof (the caving zone, water flowing fractured zone and bending sinking zone), "Down Three Zone" Theory of coal seam floor (mining damage zone, water-resisting zone, water-conductive zone) and “Water inrush coefficient” Theory, we analyzed the water inrush risk and divided potential dangerous subareas of water inrush from coal seam floor while mining lower-group coal seams.
Rock physical and mechanical tests In order to hold down quantities of drilling project, the test rock samples were drilled under the shaft.
According to rock physical and mechanical test results, angles of internal friction of these three rocks are 59.61º, 46.20 º and 43.96º respectively(table 1), we choose their weighted average 54.19º (or 0.945 radians)as the angle of internal friction of the stratum.
Ultrasonic Simulation of Seismic Waves Affected by Mine Water Invasion in North China Coalfield[J].
The study of influential factors of Ordovician limestone water inrush under floor in following coal of Zhangcun mine[J].

Le 1,c 1 College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, China a meymquan@scut.edu.cn, b zhaojing8319@126.com, cangel_tree@sina.com Keywords: Cutting temperature, Natural thermocouple, Online measurement, Real-time monitoring Abstract.
Take the monitoring based on cutting force measurement for example, because of the installation condition limitation of dynamometers, it is used only in laboratorial commonly; there are a lot of factors causing cutting tool vibrations and signal noises in machining process; it is difficult to establish some definite relations between the tool performance, the machined surface quality and the signal characteristics of machine spindle power, or vibration and acoustic emission.
Cutting heat and its induced temperature affect cutting tool performance and machined surface quality directly.
The modified spindle structure is shown in Fig. 1. 1. fixed wire terminal 2. plastic plug 3. sealing cover 4. copper cup 5. insulator 6. mercury 7. pulling shaft nut 8. wire 9. spindle pulling shaft Fig. 1 The structure of spindle pulling shaft and current collector The most important property of the current collector is the magnitude of auxiliary frictional potential caused by the disturbance of the fixed wire in the mercury.
Changho: JSME International Journal, Series C: Mechanical Systems, Machine Elements and Manufacturing, Vol. 46 (2003), pp. 314

Spectral Elements for Flat Shells The spectral element discretization based upon quadrangular elements is quite similar to classical FE in many points, but a few variations in construction result in significantly improved element properties.
In Fig. 4, the velocities of the different modes of propagation are plotted over the frequency for the 1.5mm thick glass fibre reinforced plastic (GRFP) plate with properties listed in Table 1 for α = 30°.
The elastic material properties provided by the manufacturer are given in Table 1.
Material properties of unidirectional glass fibre reinforced plastic (units in GPa and kg/m3) E1 E2 E3 G12 G13 G23 ѵ12= ѵ13= ѵ23 ρ 30.7 15.2 10 4 3.1 2.75 0.3 1700 The fibres are oriented in y direction.
The elastic and viscoelastic material properties are provided in Table 3.

Retrogradation properties of bread crumb A differential scanning calorimeter (Q2000 Model Differential Scanning Calorimeter; DSC-TA Instruments, New Castle, DE, USA) was used to study the retrogradation properties of bread during storage.
The endothermic properties were analyzed by the software supplied with the instrument.
Rheological properties of rice starch–Mesona Blumes gum mixtures.
Assessment of hydrocolloid effects on the thermo-mechanical properties of wheat using the Mixolab.
Impact of different baking processes on bread firmness and starch properties in breadcrumb.

In the electrospun fibers, the peak at 2q = 18.4° was significantly decrease compared to that of casting film, confirming that mechanical stretching occurs and a nonpolar a-phase structure is transformed to a polar b-phase structure by electrospinning.
The main origins of piezoelectric responses can be divided into to two factors; one is beta phase ratio and the other is molecular dipole alignment in the electrospun fibers.
Charge density per volume value is affected by electrospinning conditions such as material, solvent, concentration of solution and applied voltage [17].
When the electric field generated by residual charge affect to dipole orientation of electrospun PVDF-TrFE fibers, the piezoelectric performance can decrease with distance.
Summary PVDF–TrFE electrospun fibers were fabricated by FFES and confirmed to have piezoelectric properties.

This is not without consequence because lowering the yield strength may affect the strain controlled low cycle fatigue (LCF) behaviour or thermo-mechanical fatigue (TMF) behaviour by increasing the plastic deformation amount for a given applied stress or total deformation and therefore reduce the number of cycles to rupture.
Several factors are generally reported to have an influence on the Y.S. behaviour of such alloys.
Modifications of alloy composition are thus inferred to affect mainly the levels of solid solution strengthening of both γ and γ’ phases, the APB energy (APBE) of the ordered γ’ phase which controls the shearing of the γ’ precipitates by pairs of ½<110> dislocations and the γ/γ’ lattice parameter mismatch which induces coherency strain hardening.
All this parameters are known to affect the mobility of the dislocations and consequently the YS.
The intrinsic properties of the γ phase, linked to its chemistry, may also play a role in the mobility of the dislocations which propagate by combined slip and climb mechanisms.