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Although there have been no MSD attributed accidents in the last twenty years, there is, however, a serious concern that MSD could occur again in the commercial aircraft fleet and it could potentially affect any ageing aeroplane in service.
Mechanical properties of AA 2524 are: young’s modulus 70GPa, yield strength 332 MPa, ultimate strength 463 MPa.
The curves of crack growth rate da/dN vs. stress intensity factor (SIF) range ΔK of the seven specimens are shown in Fig.1.

Due to its character of very brittle, poor mechanical performance, weak seepage force and poor dispersion property at low temperature, the application of native starch is limited[2].
Fertilizers are the main factors that limit the production of agriculture, so it is very important to improve the utilization of fertilizer nutrients.
Nitrogen, the most vital nutrient for crops, has commonly been considered to be the yield-limiting factor.
The urea can be released only if the SPAM /urea membranes reach a certain swelling rate. 3.2.3 Release of urea from the SPAM /urea composite films in soil Because there are many factors that could affect the release ofurea from loaded SPAM in soil, such as the kind of soil, watercontent, bulk density, urea concentration, gel collapse and so on, there must exist obvious differences for urea releasefrom loaded SPAM between in distilled water and in soil.

Introduction Up to 1958 no formal fatigue requirements exist only static strength considerations plus safety factors were expected to preclude fatigue damages.
The essential property of the new test facility is the absolute proportionality of the load distribution and the genuine sequence of loading.
The force are produced hydraulically and transmitted by mechanical means to the test specimen, which jacks which are working in tension as well as in compression.
At the end of the fatigue test an ultimate test with factor of 1.5 up to 9g was done.
Not only safety factors are defined but also initial crack sizes, probability of failures were categorized.

Mechanical components, used in automotive, aerospace, naval structures, nuclear plants etc, are subjected to unsymmetrical loadings, with a mean stress different from zero.
Therefore, fatigue life and fatigue limit are assumed to be controlled by crack propagation law and threshold stress intensity factor, respectively.
Table 1 : Chemical composition of the C35 steel Fe C Mn Si Cr Ni Cu 98.4% 0.36% 0.6% 0.27% 0.14% 0.07% 0.07% The main mechanical properties are : Young Modulus E = 205 GPa, the 0.2% offset yield stress Rp0.2% = 350 MPa, the cyclic yield stress Rpc0.2% = 280 MPa, the ultimate tensile strength Rm = 580 MPa and the fracture elongation A = 31%.
· Propagation phase seems not affected by the mean shear stress. 
[3] Shigley JE, Mischke CR, Mechanical Engineering Design, Fifth edition, McGraw-Hill, New York, 1989.

A minute mechanical loading apparatus (Nanofactory Instruments AB, SA2000N) built in a TEM specimen holder was used.
The critical stress intensity factor, KiC, is evaluated as 0.76 MPam1/2; here, Ki is the total stress intensity factor defined as Ki = (K12 + K22) 1/2.
Thus, the plastic deformation of the Cu layer would affect the delamination behavior.
The plastic property of Cu used in this section was evaluated on the same material in the in situ TEM experiment.
This indicates the stress intensity factor range is below the threshold.

To understand the mechanical behaviors of nanocrystalline materials and to design them for desired mechanical properties, it is critical to fully understand their deformation mechanisms.
Introduction Nanocrystalline materials have been reported to have superior mechanical properties such as high strength, which in a few cases also coexists with very good ductility [1-3].
These superior mechanical properties are attributed to their unique deformation mechanisms, which are different from those in their coarse-grained (CG) counterparts [4-8].
As will be discussed later, the stacking fault energy is the main factor that affects the a E-mail: yzhu@lanl.gov above size ranges, especially the critical grain size for the transition from lattice dislocation slip to deformation twinning.
Similar observation was also reported in Ti processed by surface mechanical attrition treatment [40].

It was suggested that mechanical rubbing forces the polymer chains in the surface region to orient parallel to the rubbing direction [3], and this orientation of the polymer chains, having been confirmed using a variety of methods [4-8], is believed to be the key factor for the alignment of LC molecules.
Here, we demonstrate that mechanical rubbing creates optical anisotropy at PI surface.
Linearly polarized light reflected at an oblique angle of incidence from an absorbing sample becomes elliptically polarized, and this change in polarization contains useful information on the optical properties of the sample.
Spectroscopic ellipsometry (SE) is well suited for probing bulk optical properties, and has also been used to study rubbed PI films [7].
Whereas the opportunity for ellipsometry to be a real time monitor to obtain information in situ on dynamic properties is limited as optical anisotropy measurement by ellipsometry requires sample rotating.

This leads to a large gate-drain capacitance Cgd, which negatively affects the switching behavior of a TFET-based inverter, and is responsible for large overshoots of the output voltage, which further degrade the switching time.
CMOS logic is faster than TFET in both (a) self-loading and (b) constant loading, because it provides higher drive current at VDD = 0.4 V and is not significantly affected by the Miller effect.
An even greater performance loss affects the TFET inverter if a heavy capacitance load is applied.
Analysis approach The quantum-mechanical treatment for the investigation of the SL-FET is carried out self-consistently solving the open-boundary Schrödinger-Poisson equations in the effective-mass approximation with cylindrical coordinates.
Different material pairs provide different device characteristics because of the different energy filtering properties related with the material electronic structure, such as the electron mass and the barrier height between the two materials.

The flow can assume different configurations, called flow patterns, which will depend mainly on the physical properties of the fluids, volume fraction and flow rate of each phase, relative velocities and geometry of the flow channel.
Core-flow stability depends on several parameters such as fluid velocity and properties, tube position and geometry.
The properties of the fluids used in the simulation are shown in Table 1.
Table 1 - Fluid properties used in the simulation.
Journal of the Brazilian Society of Mechanical Sciences.21 (1999) 233-244

Introduction The relatively new nanocrystalline materials have received a great deal of attention as advanced engineering materials with improved physical and mechanical properties [1].
They can be produced using several techniques [2-7], via physical, chemical and thermo-mechanical means.
This is quite similar to the coarser ones in Fig. 1(a), the only clear difference being its lower size scale factor.
A summary of experimental conditions and mechanical properties (temperature and pressure of sintering, density of the compacts after sintering, resulting hardness and yield strength) is reported in Table 1.
In fact, all the refined microstructures having the grain size value shown in Table 4 are affected by extinction contours [33,37], denoting a thermal instability of the ultrafine structure upon reheating.