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Introduction Semiconducting oxide sensors have been extensively studied due to their high sensitivity to a large number of gases [1].
The reason for this is in Polycrystalline thin films and at sufficiently High Temperatures, a periphential Diffusion of Gases at grain boundaries can generate inhomogeneous depletion Layers.
Thinner the film, more deep is the depletion layer and hence more scope to adsorb more number of gas species on the surface.
References [1] Raluca Savu, Miguel Adolfo Ponce et al., Grain Size Effect on the Electrical Response of SnO2 Thin and Thick Film Gas Sensors, Material Research, Vol. 12, No. 1, 83-87, 2009

If plant population was too high, then crop net photosynthesis process would be affected due to less light penetration in the crop canopy as well as increase in the competition for available nutrient which will affect grain yield and forage production.
Crop growth rate during emergence to maturity was calculated by subtracting total DM at emergence from total DM at maturity and dividing by the number of days of the emergence to maturity period.
Tillage of deep loosening maintained CGR different to the CT, despite a 9.38% lower CGR before flowering stage, the number was 30.92% higher from flowering to maturity.
Conversely, it decreased crop growth rate during grain filling stage because of low radiation use efficiency and low incident radiation.

We clarify that why mullite nuclei can generate changeable crystals from two ways, crystal growth habit and grains superimposed manner, and calculate the surface energy of the four different surfaces by using first –principles calculations and basing on mullite crystal structure constructed theoretical model.
N is the number of effective atoms in the model.
Then we can get the formula of mullite crystal surface energy: g = (Estab – NEbutk) / 2A (2) N is the cell number of the slab mold. γ is the surface energy of N crystal surfaces.
Its grains mainly grow in the direction of (001) surface and present to be columnar (Figure 2).

The role of deformation twinning in strengthening and ductility of h.c.p metals has been the subject of a number of investigations [3-5].
For magnesium and its alloys, although different twinning modes have been observed by a number of authors, it is quite common for twinning to occur on the plane [6, 7].
It can be found that the sample possesses nearly equiaxed grains with grain size of ~50 μm, and the obvious residual intermetallic compounds cannot be found.

However, any further increase in pH suppressed grain growth of the whiskerlike morphology.
In particular, the reaction production at pH 11.5 (Fig. 5(d)) showed homo- geneous ellipsoidal particle shaped precipitates (ricelike grains), which are seen to be clearly different from the whiskerlike precipitate obtained at lower values of pH.
It is suggested that the reason underlying this behavior is as follows: the high degree of supersa- turation in solution at the higher pH (∼11.5) results in the growth on a larger number of nuclei, which suppresses the development into the whiskerlike phase.
This infers that the number of HPO42 ions in the reaction product increases with decreasing pH in the calcium deficient nonstoi- chiometric chemical composition give by the equation, Ca10-x(HPO4)x(PO4)6-x(OH)2-x (0 ≤ x ≤ 2).

The Lu 3+ ion is small (r=0.861 Å) [4], which combined with its high Z-number (71), gives a very high density of electrons.
The advantage of using nanopowders instead of micron-sized classic phosphors comes from the fact that nanosized particles scatter light photons to a significantly lower degree than the larger grains [10,11].
Such a microstructure is perfect for the most efficient packing in a screen since the empty sections between grains are minimized.
We are obtaining a growing number of results, which seem to confirm this supposition.

Hot rolling, due to recrystallization, will reduce the average grain size of a metal while maintaining an equiaxed microstructure where as cold rolling will produce a hardened microstructure.
Fig. 2 Deformation in rolling As the rolling process breaks up the grains, they recrystallize maintaining an equaxed structure and preventing the metal from hardening.
Fig. 6 Electro-hydraulic servo system with mechanical load A servo-valve is a complex device which exhibits a high-order non-linear response, and knowledge of a large number of internal valve parameters is required to formulate an accurate mathematical model.
a QvAQ xAV dtdP −⋅− ⋅+ = 0 / β , [ ]ei bb bb b QQvAQ xAV dtdP −+⋅+− ⋅− = 0 / β (14) bbaaP PAPAF ⋅−⋅= Furthermore the internal leakage oil flow (Qi) increase the required cylinder's oil flow which increase the pressure drop on the servo valve so the maximum acting force decreasing Eq. 3,4: 2 2       ⋅⋅ ⋅−= ss a Sa xwc Q PP ρ , 2 2       ⋅⋅ ⋅+= ss b Tb xwc Q PP ρ (15) References [1] Meehan, P.A., Edwards, W.J., Wallace, G.A.: Modelling and Simulation of Vibrational Phenomena in Rolling mills, Proceedings of the 7th International Conference on Steel Rolling, Chiba, Japan (1998) [2] Tlusty, J., Chandra, G., Critchley, S., Paton, D.: Chatter in Cold Rolling, Annals of the CIRP Vol. 31/1/ (1982) [3] Halnay A., Safta C.A., Ursu I., Ursu F.: Stability of Equilibria in a Four-dimensional Nonlinear Model of a Hydraulic Servomechanism, Journal of Engineering Mathematics, Volume 49, Number

Although, a large number of constitutive models have been proposed by various researchers, only a few have been used practically because of the difficulties in determining the material constants.
The number of data points are same for all the curves and thus the serration is a material phenomenon and has nothing to do with the sampling rate.
These solute Mg atoms can diffuse at a speed greater than the speed of dislocations and make a cluster around the dislocations when they are stopped by an obstacle like grain boundaries and thus tend to “lock” dislocation motion.
Zerilli, Influences of strain rate and grain size on yield and serrated flow in commercial Al-Mg alloy 5086, Scripta Mater. 41 (1999), 1177-1184

A number of papers studied the packing density and coordination number by computer simulations, while some others presented idealized mechanical models of heaped granular materials.
Different orientations between crystal grains within the catalyst material and different heat-expanding coefficients between phases lead to different expending degrees in different directions, and then cause stress concentration at phase interfaces; that is, a thermal stress is induced inside the pellets, which changes the mechanical properties of the catalysts.
Knudsen, Dependence of mechanical strength of brittle polycrystalline specimens on porosity and grain size, J.

XRD results confirm the appearance of nanometric grains of fcc-Al in Al85Y5Ni15, Al90Y10, Al92Sm8, Al90Tb10, Al91Tb9 ( Fig. 2.).
The abrupt drop of resistivity, registered for Al80Y6Ni14 above 570K, is due to crystallization to micrometer size grains.
The bonding strength rises, when a number of empty 3d states increases within a sequence of Al-Ni, Al-Co, Al-Fe systems.
Such a low diffusity allows to form a large number of nanocrystals with a limited size.