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Quartz crystal's advantages : stable piezoelectric properties, dielectric constant and piezoelectric coefficients not affected by temperature, good time and temperature stability ; high mechanical strength and high quality factor, good dynamic response, wide linear range, high natural frequency; no pyroelectricity, insulation and good reproducibility.
One is a piezoelectric semiconductor, such as ZnS, ZnO, ZnTe, CdTe, CdS, GaAs and so on, which has both piezoelectric properties and semiconductor characteristics.
Table 1 shows the comparison of some properties of several commonly used piezoelectric materials.
Mechanical properties: The piezoelectric elements act as stress components in the hope of its high strength and stiffness, in order to obtain a wide linear range and high natural vibration frequency.
Time stability: The piezoelectric properties are not transformed over time.

Evolution of defects in the construction causes measurable changes in the dynamic properties along with evolution of stress distribution in critical construction joints.
Additionally materials that could cause threat of the catastrophe caused by fatigue wear, exceeding stress limits or emerging of plastic deformations have magnetic properties that could affect the local magnetic field.
Change of dynamic properties of structure, detected by developed model based SHM system allows to infer on technical state of object.
[8] Gontarz S., Radkowski S., Impact of different factors on relationship between stress and eigenmagnetic field in steel specimen, IEEE Transactions on Magnetics Vol. 48, Issue 3 (2012)
[10] Sander D., Enders A., Kirschner J., Stress and magnetic properties of surfaces and ultrathin films, J.Magn.Magn.Mater. 200 (1999) 439-455

Referring to Al foundry, one factor affecting the fluidity of Al alloys is the pouring temperature.
The presence of oxides has a deep effect not only on mechanical properties but also on the material castability.
Fluidity is not exactly a single physical property, such as the density or viscosity, but a complex physical as well as technological property that depends on many factors.
Miodownik, Material properties for process simulation, Mater.
Ferraro, Effect of grain refinement and cooling rate on the microstructure and mechanical properties of secondary Al-Si-Cu alloys, J.

Because of large ground pressure and difficult to shape of field core-drilling when sampling, complete massive coal and rock samples of uniform mechanical properties and uniform lumpiness were sampled in the field, brought back to laboratory and further made into standard specimens.
Sample were made according to the relevant regulations of our coal industry standard 《Methods for determining the physical and mechanical properties of coal and rock》GB/T 23561.1-2009 ~ GB/T 23561.16-2010.
Sample precision should meet the relevant regulations of《Methods for determining the physical and mechanical properties of coal and rock》, that the nonparallelism of two ends was less than 0.05mm, the deviation of samples’ height and diameter was less than 0.3mm, the deviation of samples’ axis perpendicularity for the end was less than 0.25°.
Bursting liability of rock refers to properties of rock deformation energy accumulated and the production of bursting destruction.
(2)When deep mining the Zhuji coal mine, the countermeasures of coal such as the previous water injection, hole-drilling method and blasting distressing can effectively change the physical and mechanical properties of coal and rock, decrease or release the elastic potential energy accumulated of coal and rock, slowdown or eliminate the bursting resistance.

A particularly important effect on the spintronic objects and other nanoscale elements properties is exerted by the structure of layers, domains, regions, films arising during their manufacture.
Conclusion The proposed mathematical model makes it possible to assess the possibility of upgrading the nanofilms deposition surface, to study the influence of sample surface preparation various factors.
Reddy, Plasmonic and nonlinear optical absorption properties of Ag:ZrO2 nanocomposite thin films, Plasmonic. 9 (2014) 129-136
Tokura, Topological properties, and dynamics of magnetic skyrmions, Nature nanotechnology. 8 (2013) 899-911
Petukhov, Functional Semiconductor Nanostructures in Porous Anodic Alumina Matrices: Modeling, Synthesis, Properties, Apple Academic Press, Waretown, 2019

Plastic deformation over the top surface of the centre of the rail was less, consistent with expected mechanical property advantages of martensitic stainless steel over medium carbon rail steel (hardness, toughness, flow stress).
Factors contributing to these results include; (i) the higher hardness of the martensitic stainless steel over the rail steel, (ii) changes in head hardness of the head hardened steel as a function of depth and (iii) surface strain hardening effects associated with deformation during service life.
Further SEM-EBSD and advanced electron microscopy will be required to relate this to microstructure and properties.
Compared to head hardened rail, the laser coated IRJ suffered less damage for the same heavy haul lifecycle, apparently due to the improved mechanical properties of martensitic stainless steel over medium carbon rail steel. 3.
Two approaches might be considered to improve the properties of the coated IRJ; redesigning the shape and position of the hard facing region to reduce surface deformation mismatches during service and selection of a weld deposit material of compatibility of thermal expansion properties.

Introduction Hemihydrate calcium sulfate whiskers is a promising reinforced material due to its high mechanical properties, but it has the characteristics of hydration too when it is in solution or at moist atmosphere.
Therefore, to investigate factors affecting the hydration of whisker is of primary importance for hemihydrate calcium sulfate whiskers' industrial preparation and application.

While the extrusion process is significantly affected by the nozzle, the thermal conduction and thermal deformation of a nozzle can impact the properties and quality of the 3D printed parts [7].
Ding et al. [9] investigated the relationship between nozzle temperature and mechanical properties of 3D printed parts.
On the other hand, although the steel nozzle shows excellent mechanical properties at the temperature around 400℃, the high-temperature extrusion of steel nozzle is limited by the poor thermal conductivity of about 15 W/(m⋅K).
Ding, Effects of nozzle temperature and building orientation on mechanical properties and microstructure of PEEK and PEI printed by 3D-FDM, Polymer Testing, 78 (2019) 105948
Qin, Effects of Nozzle Geometries on 3D Printing of Clay Constructs: Quantifying Contour Deviation and Mechanical Properties, Procedia Manufacturing, 48 (2020) 678-683

During operation mechanical structures can experience large vibration amplitudes.
The design process of the UPD test rig was driven by the above mentioned parameters and by minimising external factors that would affect the quality of the nonlinear measurements.
During commissioning of the rig, the settling of the damper was identified as the main issue affecting the quality of the measurements.
Nitsche, "The role of friction In mechanical joints," Applied Mechanics Reviews, 2001
Schwingshackl, "The effects of boundary conditions, measurement techniques, and excitation type on measurements of the properties of mechanical joints," in Proceedings of the Society for Experimental Mechanics IMAC Conference, 2016

Composite pipelines made up of glass fibres reinforced epoxy resins are increasingly used, especially in oil and gas industry, for their good mechanical properties, combined with reduced weight and excellent behaviour under hostile environment conditions.
The conclusions point out the schemes and the optimal parameters of evaluation as well as the application limits of thermographic inspection Introduction Composite pipelines made up of glass fibres reinforced epoxy resins are increasingly used, especially in oil and gas industry, for their good mechanical properties, combined with reduced weight and excellent behaviour under hostile environment conditions.
In order to solve the differential equation of the thermal conduction in a particular situation it is necessary to know the real conditions of process development, which determine the univocity of the process: geometrical conditions, which describe the dimensions and shape of the body; physical conditions, which include the material thermal properties, initial conditions, which establish the body temperature in the initial moment, boundary conditions of first type, which establish the temperature distribution at the body surface related to time ; boundary conditions of the second type, which refer to the time variation of the thermal flux density at the heat exchange surface; and boundary conditions of the third type, which establish the manner of heat exchange between the solid material surface and the environment.
To identify the affected zone each sample was divided in some equal sectors, according the equipment field of view.
The inspection was developed with the following parameters: factor of emissivity: 0.9, duration of heat pulse: variable, between 0.2 and 10 s, thermograms registered in the cooling transient process, after 2-5 s until 60 s, maximal contrast: after 10 s