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The results showed the pyramid absorbing material had the good absorbing property, and as the FeSiAl plate was the substrate the absorbing property in the low frequency 2-4GHz could be improved while the absorbing property in the high frequency 4-18GHz was better.
The ideal absorbing material should have the characteristics of absorption frequency bandwidth, light weight, thin thickness, good physical and mechanical properties, easy usage, etc.
But it has not been solved yet, in the case of civil absorbing materials, the thickness is a certain challenge to achieve high absorption rates at low-frequency, because the thickness is an important factor affecting surface impedance.
Therefore, in order to improve the absorbing properties of the material, it is necessary not only to improve the electromagnetic parameters of the material, but also to design the structure with high absorption rate as much as possible.
It was coincident with the property of the CIPs composite, the magnetic loss determined the absorbing property of the materials.

Introduction Carbon nanotubes (CNTs) have been extensively investigated for applications in many areas because of their unique physical and chemical properties [1].
However, this route induces a structural alteration of CNTs such as defects which result in a considerable change of the thermal, mechanical and electrical property of CNTs.
In this study, using this concept, we prepared the aspect ratio controlled MWCNTs which less change inherent properties of MWCNTs such as purity, crystallinity and electrical conductivity.
It is well known that aspect ratio of MWCNTs can affect the formation of conduction network which can affect the electrical conductivity of composites.
And also, the aspect ratio controlled MWCNTs with novel properties may be useful for applications in diverse areas.

But up to now, there are no systematic studies on slip-drilling pipe's contact mechanical behavior under different parameters at home, and no correlational research article was found.
From the Mechanical Design Manual, we can know that the friction coefficient between steel and steel without lubricant have the equation: μ= 0.15, therefore, μ1= 0.3159.
The plastic damage to drilling pipe in field experiment Conclusions The slip dog's profile parameters directly determine the contact mechanical properties between the slip and drilling pipe.
This paper has produced a complete set of method to assess the performance of slip dog's structural parameters, and this method is universal and practical.Elastic-plastic contact finite element analysis is an effective means to study drilling pipe-slip contact mechanical properties, which can be used to calculate a variety of slip chucking cylindrical tools.
[3] TIAN Hongliang, HU Shaoyun: Experimental study on frictional factor between chuck jaw and drilling rod, edtied by Coal Geology &Exploration,(2003)

However, during forming process at high temperatures, friction and tool wear are determining factors that can affect the efficiency of the whole process.
At high temperature a larger abrasive area and more severe compaction galling occurs that can be explained by material properties of Al-Si coating at elevated temperatures.
These intermetallics can fracture during the heating and forming processes due to thermal and mechanical loads. [1] The fractured particles plays an important role in the tool wear. [2].
Hot stamping occurs at high temperatures, thus friction and tool wear are determining factors that can affect the efficiency of the whole process.
,Hahn, I., Theisen, W., Mechanical properties of AlXFeY intermetallics in Al-base coatings on steel 22MnB5 and resulting wear mechanisms at press-hardening tool steel surfaces, Surface & Coatings Technology (2017), doi: 10.1016/j.surfcoat.2017.04.075

This area is affected significantly by typhoons.
It is always affected seriously by typhoons in summer and winter.
All these factors lead to the lack of uniform planning of navigational facilities on islands along the channel.
These factors make SCS become a high-risk area of accident, so SCS, especially in the areas around SCS islands, accidents are frequent.
[4] Shi Chun-lin, On the Present Main Factors to Affect Navigation Safety in SCS, the New Orient, No 2,2012,pp7～8

Determining how to improve the casting layer surface properties and creating better surface quality of metal products has become a research focus with each big material manufacturing enterprises at present.
In order to study the microprism reflective film work mode, namely the main factors that influence the reflective performance of nickel casting layer.
[4] Yangpei Zhao, Yinhui Huang, Junwei Zhang, etc., Microstructure and properties of pulse jet electrodeposition nanocrystalline copper [J].
Journal of mechanical engineering materials, 2006, 30(6):87-90.
China mechanical engineering, 2008, 19(6):644-647.

Analysis of Stress Distribution for Powder Compression Molding by Finite Element Method Prakorb Chartpuka* and Chaiwat Chaimahapukb 1381 Department of mechanical engineering, Faculty of engineering, Rajamangala University of Technology Phra Nakhon, Bangsue, Bangkok 10800, Thailand aprakorb.c@rmutp.ac.th, bchaiwat-c@rmutp.ac.th Keywords: stress distribution, powder compression mold, finite element method Abstract.
There are several factors that affect the density in the powder compression process; the major problem is the friction between the powder and the mold wall which result in inconsistent density throughout the net-shaping.
Both models are symmetric under the ultrasonic waves rightly affecting the mold body.
Concerning the Pre-processing, 3D model has been prepared, designed, and created with the SolidWorks program according to the material properties as shown in Table 1.
Table 1 Properties of material [4] Materials AISI 52100 AISI 1045 Elastic Modulus 210 GPa 205 GPa Poisson's Ratio 0.30 0.32 Shear Modulus 80 GPa 80 GPa Mass Density 7,810 kg/m3 7,850 kg/m3 Tensile Strength 2,240 MPa 1,110 MPa Yield Strength 2,033 MPa 710 MPa Hardness, Rockwell C 64 HRC - Table 2 Pre-processing parameters Parameters Form A Form B Form C Maximum element size (mm) 10 10 10 Minimum element size (mm) 2 2 2 Element size for control mesh (mm) 3 3 3 Total element 79,449 79,005 52,865 Total node 53,600 51,576 40,748 Applied normal force (N) 50,000 50,000 50,000 Maximum distortion energy equation in the form of stress components, shown in equation 1 (1) Average stress equation on the cross-sectional area, perpendicular to the direction of force applied, shown in equation 2 (2) Experimental Setup and Procedure for the Measurement To test the stress value, the strain gages are set

The fuel injection quantity fluctuation (FIQF) has adverse affects both on coherence and stability of HPCR system.
HPCR system is a complex fuel injection system integrated with electric field, magnetic field, mechanical motion and hydraulic action.
Model and experiment facilities Fig.1 Simulation model of the HPCR system Fig.2 Test bench of the HPCR system The HPCR system involves multiple physical fields which include electric, magnetic, mechanical motion and hydraulic action.
Factors involved in FIQF due to control valve lift are mainly due to the time taken by control valve in moving between its reset and set positions and the throttling action between control valve and sealing conical surface during fuel injection operation.
Simulation of the Magnetic Properties for Common Rail Electro-Injector[J].

It will gradually crack under traffic load and atmospheric factors, form longitudinal seams.
Using high strength clay, broken bricks, gravel and other water permeability material, or 8% low dose of lime-soil-replacement under different circumstances, in order to improve the subgrade soil compression performance and shear properties, reducing the settlement and improving the base carrying capacity.
Haul trucks should be avoided rolling directly on paved and positioned geogrid to avoid destroying the geogrid, thus affecting the quality of the construction.
If the thickness is less than 8cm, mechanical paving and compaction in conjunction with the grassroots, avoid the thin layer subsidizing phenomenon.
It not only affects road appearance, but also affects the quality of road and shortens its life, close attention should be paid.

For natural gas well in sour gas reservoirs, very serious corrosion in the gas well string is an important factor of gas production system life.
Introduction Some oil and gas wells have adverse working environments, so their service lives and properties will seriously affect the exploration and development and the operating benefits of oil and gas fields.
Corrosion due to water and other factors[1,4,5,6,7].
Despite the fact that H2S/CO2 is the most severe corrosion factor for the facilities of sour oil and gas fields (especially hydrogen sulfide, which may not only generate abrupt sulfide stress cracking of metal to cause great economic loss but also have toxicity that may threaten personal safety), the corrosion action of mineralized water cannot be underestimated.
When high sulfide-resistant and common tubings and the addition of corrosion inhibitor that was appropriate for fluid properties were adopted, the gas wells that had produced for long time could still maintain normal production.