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Introduction The nanosized crystallites are attracting a lot of interest, because many properties of the nanostructured compounds show to be anomalous when the grain diameter approaches nanometer size.
These modes involve the collective motion of large numbers of atoms which vibrational frequencies are possible to calculate using elasticity theory.
The angular number l = 0,1,2, ... measures the number of wavelengths along a circle on the surface of the particle.
These degenerate modes are labelled by the number m.
o o o -1 04812 0 5 10 15 20 25 30 S1 D0=4.4 nm σ=0.35 0481216 S2 D0=6.8 nm σ=0.32 0 2 4 6 8 10 12 14 0 10 20 30 40 50 60 70 Number of particles D(nm) S3 D0=5 nm σ=0.25 Figure 2.

Wireless sensor network technology has the potential to reveal fine-grained, dynamic changes in monitored variables of outdoor landscape.
Especially as the development of modern agriculture, microclimate information requires more fine-grained, more precise, and more real-time.[1] The on-going technological developments in the miniaturization of electronic devices and wireless communication technology have led to emergence of wireless sensor networks (WSN) which make it is possible to acquire microclimate information more timely, accurately and conveniently.
The total sample number is about 3000 and the sampling cycle is 4 hours.

These computational models would have great value in increasing the understanding of the cutting process and in reducing the number of experiments which traditionally are used for tool design, process selection, and machinability evaluation.
E [GPa] n [ - ] a [10-6/K] l [W/mK] cp r [N/m2K] 210 0.3 11 42 3.6 106 The Selected tools for this investigation were uncoated and fine-grain carbide (grain size 0.5-0.7mm) gundrills (d = 2.5, 8.0 mm, ISO HW-K15).
Summary To reduce the number of gun drilling tests required for tools optimization and to increase the understanding of the high performance machining process gun drilling, a uniform computational model has been developed by using the commercial implicit FE code Deform-3DTM.

area 58 87 183 53 22 24 194 194 PM2.5 four moderate  pollution the Textile  City 45 91 173 51 23 25 188 188 PM2.5 four Moderate  pollution Xiao Zhai 65 68 193 83 20 24 175 193 PM10 four moderate  pollution  stadium 47 83 207 85 34 39 205 207 PM10 five heavy  pollution  western High-Tech 59 90 198 65 27 33 211 211 PM2.5 five heavy  pollution economic  Development zone 52 70 180 63 23 29 196 196 PM2.5 four moderate  pollution Chang’an area 48 41 157 77 30 37 179 179 PM2.5 four moderate  pollution Yanlaing area 53 50 172 63 24 32 191 191 PM2.5 four moderate  pollution Iintong area 54 88 138 65 24 28 179 179 PM2.5 four moderate  pollution Qujiang group 47 97 174 79 17 22 183 183 PM2.5 four moderate  pollution Guangyun tan 52 94 186 79 28 32 204 204 PM2.5 five heavy  pollution Grass beach 54 51 161 91 22 29 210 210 PM2.5 five heavy  pollution Evolution law of PM2.5 PM2.5 is a kind of fine particulate matter and its basic movement is random Brownian motion. is Set as the grain
quality, and is the grain displacement, then its motion can be described by Lagevin equation as follows: (2.3.1) The above formula means the force 0f Brownian particles is the sum of viscous resistance and stochastic force.Where, is a random variable satisfying the following conditions:.
-15 -10 -5 0 5 10 -15 -10 -5 0 5 10 15 2 hours of concentration distribution X Y -30 -20 -10 0 10 20 -25 -20 -15 -10 -5 0 5 4 hours of concentration distribution X Y X -30 -20 -10 0 10 20 -25 -20 -15 -10 -5 0 5 6 hours of concentration distribution Y -30 -20 -10 0 10 20 -25 -20 -15 -10 -5 0 5 12 hours of concentration distribution X Y Fig. 7 The concentration simulation diagram of PM2.5 Conclusion PM 2.5 is not an air pollutant composed of a single component but a complex and variable atmospheric pollutant composed of various man-made or natural pollution sources and a large number of chemical components.
A large number of primary particles produced during certain industrial process and surface dust from buildings, farm, and wind erosion etc. are smaller pollution sources of PM2.5.

Gao et al. [4] performed the high-speed weld of ultra-fine grained steel by using this technique.
These parameters can be described by the following equations: （2） （3） According to Rosenthal equation, the temperature T at any location within the plate can be described by the following equation: （4） here Pabs represents the laser power absorbed by the material; δ is the thickness of the plate; k is the heat conduction coefficient; α is thermal diffusion coefficient and ; T0 represents the original temperature of workpiece; K0 is the second kind Bessel function in a modified form; Pe represents the Peclet number.
Finally the energy effectively absorbed by the workpiece can be calculated by: （5） here n is the total number of the slices.
Laser-TIG hybrid welding of ultra-fine grained steel.

Before aging a dense network of dislocations is observed inside the grains.
These dislocations are arranged in cells and many grains are heavily twinned as shown in Fig. 2b.
There is no increase in the number or size of dislocation cells, as shown by the index (i).
Table 2: Characterizations of TiC nano-precipitates for each aging heat treatment   number of counted precipitates Mean spherical diameter (nm) Mean density r (m-3) Volumic fraction (%) 650°C – 100h [4] - 6 - ≈ 0.4 600°C – 500 h [11] 97 4.3 ± 1,7 4 ± 2 x 1022 - 600°C – 1000h (our measurements) 921 4.3 ± 1,6 2.1 ± 0,5 x 1022  0.095 550°C – 1000h (our measurements) 680 3.0 ± 0,9 1.7 ± 0,5 x 1022  0.030 500°C – 4775h (our measurements) 64 2.4 ± 0,5 6.3 ± 2 x 1021  0.0046 Effect of aging on tensile behaviour Figure 4 compares the engineering stress-strain curves obtained at 20°C from tensile tests on tubes that were aged for 1000 hours at 400, 500, 550 and 600°C.

The slurry mixture obtained then carried out a viscosity test with digital viscometer NDJ 8S using rotor number 2 and rotor speed of 30 rpm.
In addition, it appears that irregular grain shapes with small size.
However, irregular grain shape with a wide particle size distribution is advantageous because it can provide an interlocking effect that can make the coating layer dense and evenly distributed[11]. 40µm 40µm 40µm c b a 40µm 40µm 40µm f e d Figure 4.
Acknowledgement This research is conducted under research grant by Directorate of Research and Community Service University of Indonesia “Hibah Publikasi Internasional Terindeks untuk Tugas Akhir” with agreement number NKB-0721/UN.R3.1/HKP.05.00/2019 References [1] U.

The issue of the urban environment decoration, which is the residence place for a considerable number of people who seek aesthetic pleasure, has continuously been the task of urban architecture authority and it is quite successfully performed [1-4].
Properties of the soil taken for research Grain size composition/distribution, % Grain size, mm 2-1 1-0.5 0.5-0.25 0.25-0.071 <0.071 0.4 1.6 32.8 60.2 5 Liquidity limit, % 7.5 Optimal humidity at maximum density, % 7 Maximum density at optimal humidity, g/cm3 2.148 Table 2.
The approach applied to the experiment enables the use of mathematical planning to accelerate the time of its implementation and reduce the number of samples without losing the intermediary results and with sufficient statistical evidence.

PLGA grains (LA/GA=70/30, Mw=7.31×105, Mn=3.19×105, PI=2.29) were provided by Institute of Chemistry, Chinese Academy of Sciences.
PLGA grains were thoroughly dissolved in 1,4-dioxane.
Acknowledgements We would like to thank the Hi-tech Research and Development Program of China for supporting this work under grant number 715-009-0160.
This work is also supported by the National Natural Science Funds of China under grant number 30300356, 50577067.

Because the hardness of stainless steel is relative low the sand grain and the adhesion thing fell off will scratch the surface of the surface of the hole.
Table 1 Proportion of each ingredient of oilstones Number of oilstones 1# 2# 3# 4# 5# 6# 7# Ingredient of Abrasive GC SA GC SA GC SA GC WA GC WA GC WA GC Proportion of each ingredient（%/%） 90 10 80 20 70 30 90 10 80 20 70 30 100 It is known from the honing experiment analysis[2] that the grinding efficiency of the oilstone with green silicon-carbide abrasive is higher, but the larger proportion of green silicon-carbide abrasive is, easier the oilstone is to break down.
Table 2 Proportion of the ingredients of oilstones Number of oilstones 1# 2# 3# 4# 5# 6# 7# Ingredient of Abrasive SA GC SA GC SA GC WA GC WA GC WA GC WA Proportion of each ingredient（%/%） 90 10 80 20 70 30 90 10 80 20 70 30 100 It is indicated from the honing experiment analysis [3] and the grinding ratio of several oilstones (Figure 2) that the grinding effect of oilstone No. 4 is the best according to either the grinding efficiency or adhesion situation in honing stainless steel.
According to the properties of austenite stainless steel, the oilstone with higher hardness and bigger grain abrasive may be adopted in rough honing so as to cut off more margins quickly and make preparation for finish machining.