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In general, rational fertilization can increase grain yield and improve the efficiency of the cultivated land output.
CLPSC is reflected the relationship between the single grain yield and applying pesticide.
But only in 2008, there were y>p>0, k3>1 and p maintained in a reasonable range, which was conducive to the improvement of grain yield.
In 2010, there were y1, which indicated decreasing of pesticide use caused the per unit area yield of grain larger reductions.
This illustrated the link between the single grain yield reduction and unreasonable applying pesticide was inevitable.

Introduction Rock can be represented as an assembly of cemented mineral grains which can be described by its internal microstructures.
The intact crystalline rock consists of a variety of mineral grains of different sizes, and of close contacts between mineral grains and microscopic defects in the form of cracks and holes [1].
Lan et al. [1] developed a grain-based universal distinct element model and studied crack propagation in brittle rock samples with different heterogeneities.
No new cracks generate since number of broken bonds remains zero at this stage.
Moreover, Fig. 5 shows that crack number and type is almost unrelated with heterogeneities.

Microstructure of the base metal (Fig. 2, a) deformed at the temperatures of β area without HT consists of large β grains with unrecrystallized lamellar α phase in the volume of the grain, grouped into colonies. α phase plate thickness is 0.7 - 2 microns.
In between α colonies and α plates there is β phase grain.
HAZ after welding consists mainly of large grains of pure β phase, detected during rapid cooling, with intermittent release of the second phase observed only at the grain boundaries (Fig. 2, b).
At first fine recrystallized grains formed along boundaries of large β grains.
It is obvious that in the structure of these joints at 750 ºC the number of detected metastable phases, the decay of which at different modes of heat treatment would affect the mechanical properties of the joints, is not sufficient.

From the materials perspectives, akin to fusion welding in many respects, AM involves a multitude of complex and interacting physical phenomena such as heat transfer, fluid flow, discrete and continuum mechanics, sintering, melting, solidification, solid state transformations, grain growth, diffusion, textures etc.
Other considerations that need careful thoughts are relevant to ensuing cooling rates that would affect the grain structures, phases and mechanical properties.
From process perspectives itself, additive manufacturing brings in to foresight a number of complex interacting physical phenomena such as: Heat transfer, Fluid mechanics, continuum mechanics, melting, solidification, solid state phase transformations, grain growth, textures, diffusion.
Further complexity arises as the number of process variables that include input materials interact to control the deposit characteristics such as: deposit dimensions, stress state, extent of lack of fusion, gas porosity, structure & chemical gradients.
The role of feedstock powders needs careful investigations as the grain homogeneity and shape are known to affect the profile of the deposit bead and the extent of projections that diminish the surface quality as well as the process stability.

Figure 5: Residual stresses of the different component variants The fatigue strength of the component also depends on the grain structure of the material which is shown in Fig. 6 for the different variants.
The fine grain structure of the variants V4 and V6 results from the annealing.
The grain sizes of V3 and V5 are similar to each other and in comparison to the others these variants have the coarsest structure.
On the horizontal axis the number of load cycles is shown.
That might be taken as an explanation that they show similar behavior at small numbers of load cycles i.e. in the regime of finite fatigue life Summary The component variants produced by cold forging show enhanced properties in comparison of machined component variants in terms of endurance limit.

Addition of Ag, for example, elevates dissolution temperature of GP zones and addition of Fe slows down aging rate due to refinement of grains [8].
All specimens were equal in average grain size, about 150mm, due to the homogenization at 823K.
The maximum stress amplitude and the number of serration are presented as a function tA in Fig.4 (a) and (b), respectively.
It is clearly seen from Fig. 5 (b) (a) Fig.4 Variation of (a) the maximum stress amplitude and (b) the number of the serration with the aging time at 293K for the Al-6%Zn specimens after quenching from 473K.
It might be thought that grain refinement and/or intermetallic compound formation themselves promote the appearance of serration, but the grain size and the state of intermetallic compound did not alter during the aging.

To reduce the size effect, periodic boundary condition is used to reduce the effect that the number of atoms is less than in a real environment.
Polycrystalline material means in each local region the atoms are arranged in periodic, but on the whole, the orientation and arrangement of atoms in different regions are different, thus forming a structure consisted of many grains in different orientations.
Nano-crystals have large proportion of grain boundaries, so it has excellent properties like high strength, super plasticity and high hardness.
Different from the mechanism of single crystal, there are almost no dislocations existed in the polycrystals with large amount of grain boundary atoms.
This method makes grains too symmetrical and idealistic, so there are some differences between the model and the actual materials.

It can be noticed that grain growth is structurally anisotropic.
The grains in the samples are plate-like, which is characteristic BLSF ceramics [9,10].
It also can be found that the ceramics consist of well-developed grains less pore and clear crystalline boundaries.
The CSBTi-0.1, CSBTi-0.15 exhibit larger grain (average particle size about 8-10µm) as compared with other doped samples.
But when a large number of Ca doping, Ca dopant may substitute A-site Bi ions, low-valent Ca 2+ ions were introduced as acceptor doped to substitute for Bi3+ ions.

Etching used to get the geometry (size and shape) morphology of grains and porosity of each using 1% NaOH +95% H2O+4% KMnO4 reference [10] and 5% HF + 95% H2O.
Operation of Eq. 3 is reached number value Re = 13938 based on the criteria of type of flow occurs eddy or turbulent.
From this turbulent flow causes the gases trapped in the casting product which numbers Re> 10000, resulting in gas porosity.
Reference [14], provides the element Fe in aluminum alloys to form intermetallic phase that resulted in equiaxed grain structure.
Wilkinson, Effect of Thermomechanical Processing on Grain Structure Development in a Twin-Belt Strip Cast Automotive Aluminum Alloy, Metallurgical and Materials Transactions A. (2004) Volume 35A

To achieve the objective of low operating temperatures, a number of approaches from the viewpoint of new materials, novel processes, and unique architectures have to be re-examined.
At 200°C, both ScSZ and SDC layers contains small grains.
The grain size of SDC layer is significantly larger than that of ScSZ layer in the bilayer film.
SDC layer contains columnar grains with grain diameter of about 60-70 nm oriented perpendicularly to the substrate, while the grain size of ScSZ layer is around 30 nm and the grain orientes randomly.
The grain diameter for SDC layer is about 60-70 nm while for the SzSZ film it is around 30-40 nm.