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But fertilizer efficiency was low, which directly affected the farm incomes and grain yields.
The reliability of simulation results with the Amesim/Simulink respectively combined simulation model parameters, the PID, and the size of the model parameters and their gain .Joint the Amesim/Simulink simulation model parameters directly affect the final simulation results. , , and parameters of the PID gain different size directly affect the results of simulation and the model of the dynamic process of oscillation frequency and steady state process speed fluctuation .Use of single variable control PID parameter setting in Simulink, and the setting process as follows : Tab 2 Controller critical value conversion experience formula Number Control mode Proportional band Integration time Differential time 1 Ｐ 　 2δk 　 ∞ 0 2 PI 　 2.2δk 　 0.833Tk 　 0 3 　
References [1]LiHongli,Zhangweifen.Chemical fertilizer use and efficiency change of main grain crops in China[J].

Due to the influence of welding heat input, changes take place in the structure of heat affected zone with grains becoming larger; The formation of carbon chromium compounds result in diminished the capacity of samples’ self-passivation.
At the same time, microbial produce a large numbers of metabolic products.
Non-uniform grains in welding heat affected zone and the carbon- chromium compounds cause corrosion resistance more worse.

S. steels, a number of both Japanese and British grade steels also have been friction stir welded.
Results are for longitudinal samples and thus contain only the fine grain, weld metal microstructure.
A lower peak temperature results in a finer ferrite grain size associated with the higher travel speed, higher strength weld.

Three-electrode system was used to test the polarization Table 1 LY12 Aluminum alloy chemical composition (wt %) element Al Cu Mg Mn Fe≤ Si≤ content 91.4-93.7 3.8-4.9 1.2-1.8 0.3-0.9 0.5 0.5 Table 2 Experimental process condition and parameters Sample Numbers Current density (A/ dm2) Sample area (dm2) Test current (A) Eventually voltage (V) Concentration solution (g/L) PH Oxidation time (min) 1 4 0.138 0.55 510 15 11 25 2 8 0.138 1.10 510 15 11 25 3 12 0. 138 1.65 510 15 11 25 curve for four samples.
It can be seen that microarc oxidation ceramic film is formed by the combination of small grain which possess tiny hole in the centre and grow by the type of volcano awl[9].
In domain arc discharging, ceramic film is centered as tiny holes, though produced oxide continuously melt and rapidly solidification and combine with each others to thicken. with the increase of microarc oxidation time, the block grain formed later cover the earlier volcano and these link together with the type of cross-bridge, form a big ceramic connect skeleton.

When using PFC, a large quantity of back-calculation of micro-mechanical parameters such as cement and grain stiffness and strength from laboratory test results are needed.
During initialization, FLAC sends the number of segments and the coordinates of each segment to PFC.
Table 1 The properties of schist used in PFC/FLAC coupling simulation PFC assemble Ubiquitous joint model in FLAC property value property value Grains Intact rock mass Rmin [mm] 7.2 Youngs modulus (GPa) 4.6 Dmax/Dmin 1.66 Poisson's rate 0.32 r [kg/m3] 2700 Cohesion (MPa) 0.58 Ec [GPa] 6.1 Friction angle ( °) 33.28 kn/ks 2.5 Dilation angle ( °) 0 m 0.5 Cement Bedding plane l 1 Cohesion (MPa) 4.3 Ec [GPa] 7.2 Friction angle ( °) 35 Kn/ks 2.5 Dilation angle ( °) 0 sc [MPa] 7±2 tc [MPa] 7±2 Fig. 4 present the simulation results of PFC/FLAC coupled model, in FLAC model, we used the plastic zone to present the EDZ, in PFC model the crack distribution was directly used to present the EDZ.

Introduction Nano calcium carbonate is the chemical synthesised product whose grain diameter is in the context of 1-100nm rang.
Nano calcium carbonate also widely used in rubber, papermaking, coatings, printing ink, etc. [1-6] Surface effect is the properties change due to the ratio of nano surface atomic and total number of atoms sharply increasing along with the diminishing of the nano particle size.
The grain size also fluctuated with the amount additive A increase, when dosage was 0.3 wt.% Ca(OH)2, a maximum of 47nm was achieved, and a minimum size of 36.5nm emerged at dosage of 0.7 wt.% Ca(OH)2.

In the case that various stocks of resources cannot be fully shared in the manufacturing enterprise group, when there is a surge in the number of projects, the resources will become relatively limited, the competition for resources will frequently emerge, resulting in lower product quality, longer development cycle and higher development cost.
In this mode, the resource sharing and application are tight coupling and privatization because of the big grain degree, low utilization rate and the particular realization of information integration and process integration.
Without consideration of resource services for multiple users or tasks, the coarse grained resource encapsulation can’t meet the need of multidimensional dynamic resource combination

Both green and air-dry conditions, the parameter of static bending and compression parallel to the grain have lower values for AH as compared with Teak [4].
In some cases, the perpendicular to grain tension and toughness values are lower.
The PHA can be classified depending on the total number of carbon atom within its monomer; long-chain length PHA (LCL-PHA; 15 or more carbon atoms), medium-chain length PHA (MCL-PHA; 6 to 14 carbon atoms), and short-chain length PHA (SCL-PHA; 3 to 5 carbon atoms).

A large number of combinations of different levels of these factors creates the problem of choice of optimal conditions of production of powders.
Osamu, Microstructural characteristics of large-scale ultrafine-grained copper.
Li, Ultrafine-grained copper prepared by spark plasma sintering process.

At the same time, because of the rapid solidification high speed steel powder, components uniform, less segregation and grain refinement, the wear resistance of material is improved greatly when compared with traditional fused cast high speed steel [7,8].
As the oxide particles spalled off from the matrix to produce abrasive grains, which resulted in increase of abrasive wear.
As the sliding speed increased to 1.05m/s the oxide film cracked and flaked off, and more white oxide particles scattered on the worn surface, a large number of wear debris re-pressed.