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The optical properties calculations show that, compared with the single-crystal Si layers, the absorption band of the layer of Si/Ge get narrower, and the absorption band-edge obviously get red-shift. 1.
The norm-conserving pseudopotential of reciprocal space is used in the calculation of optical properties.
Fig. 5 The optical absorption spectrum of Si/Ge layer 3.2 Optical Properties Optical properties of semiconductor materials primarily are characterize by semiconductor optical constants (refractive index, light absorption, reflection coefficient and the refractive index, etc.), and these optical constants are decided by energy band structure, carrier concentration and mobility near the Fermi.
But it has been difficult that calculation of optical properties, one of whose reasons is too much factors affecting calculation of optical properties.
Conclusions Energy band structure and optical properties of Si/Ge layer were discussed by using first principle density functional theory.

The paper introduces current researches of the work hardening in metal cutting process, analyses the forming mechanism and influencing factors of the work hardening and discusses the effects of the work hardening on workpiece service performance.
Influencing Factors of Work Hardening in Metal Cutting Due to work hardening is the result of the comprehensive effects of plastic deformation strengthening and softening of temperature rise, therefore, usually whatever factors can increase deformation and friction may force the hardening.
On the other hand, whatever factors is conducive to the softening, such as high temperature, or low melting point, can reduce the degree of hardening.
Influence of the Workpiece Material Properties.From the point of view of the physical properties of the workpiece material, the greater the workpiece material plasticity is, the greater the hardening exponent is, and the more serious the hardening is.For general carbon structural steel, the less the carbon content is, the greater the plasticity is, the more serious the hardened layer is.
The work hardening is affected by workpiece material properties, cutter parameter and cutting conditions in machining.

Excellent mechanical properties are an advantage of these materials considering their weight.
Thermoplastics significantly change their properties with temperature.
These properties can significantly affect machinability of a composite.
Basic mechanical properties of polymeric and cellulose fibres in comparison to glass and carbon fibres are shown in Table 1 [8].
It was proved that a more positive geometry (owing to a larger rake angle) significantly influences all important factors.

This paper solves the penny-shaped crack configuration in transversely isotropic solids with coupled magneto-electro-elastic properties.
The coupled properties of magnetoelectroelastic materials offer great opportunities for engineers to create so-called smart materials/intelligent structures that are cable of responding to internal and/or environment changes.
Work has been directed towards the crack tip field intensity factors.
The (stress, electric displacement and magnetic induction) intensity factors are given.
For the medium of finite size, dependencies of the local electro-magneto-mechanical fields near the crack border on the intensity factors should be same as those given by this paper for the infinite medium, since the medium boundary will not affect the qualitative character of the state of affairs near the crack border.

Wood and Fry [2] observed that when erosion corrosion and electrochemical properties of the physical characteristics of the binding occurs can have many applications, because the erosion and corrosion of liquid and solid particles have an interaction exist.
A variety of factors will affect the working results during the electrochemical machining process, such as voltage supply, electrolyte type, electrolyte concentration, initial gap and flow rate.
Due to varied factors that will affect the working result, one of the factors is changed per time during the experiment without disturbing the other factors.
In this way, the working results are studied to avoid complicating the experiment by involving other factors so as to interfere with the discussion. 2.1 Effect of voltage on removal rate and hole size The discussion result is shown in Fig. 2(a) and Fig. 2(b) of which, Fig. 2(a) explains the effect of the voltage on the removal rate.
The main reason for this is that although the additional erosion factor should be considered for affecting the working removal rate as compared with conventional electrochemical machining during the electrochemical jet-stream working process, the electrolyte still remains the main metal removal method.

Fault tree has been established in this paper by analyzing factors leading reciprocating compressor fault based on the method of fault tree. 21 minimum cut sets leading to reciprocating compressor fault can be gotten through qualitative analyses on this fault tree, the happening probability of the top event can be calculated and the importance of the basic event s can be analyzed through quantitative analysis.
Once the machines are abnormal and fault ,it will affect the normal production, bring huge economic loss .Development of reciprocating compressor fault diagnosis, fault elimination can be invisible, the normal operation of the machine can be ensured, economic benefit be improved.Application of fuzzy fault tree theory can effectively diagnose reciprocating compressor failure probability, and quickly identify the predisposing factors causing failure.
Valve fault in E1,pressure packing ring fault in E2; fault of piston ring in e3; piston and piston rod cylinder fault in E4; Cylinder fault in E5; oil wiper fault in E6; valve failure in E7; spring failure in E8.valve plate surface debris, the valve fracture, springinner surface crack, improper selection of spring,spring ,piston rod and a packing ring friction and wear, filler rod and the piston rod seal failure,packing box temperature increased,piston ring gap too small,piston ring tension too large,piston and piston rod of the mechanical properties and smoothness does not meet the requirements,the piston rod and the piston are not firmly connected,piston rod positioning terminal and the central line of the piston verticality does not meet the requirements,cooling water system in short supply,lubrication system oil supply shortage,suction valve cavity leakage,Exhaust valve jammed or broken,oil wiper wear,scraping the oil ring incorrectly installed, piston rod worn or scratched, ring side
And so on, other bottom event probability of reciprocating compressor fault tree can be calculated.calculate top event occurrence probability and the bottom event probability importance degree, find out the most important influence factors of reciprocating compressor failure ,,provide guidance for reciprocating compressor repair and management,improve its safety and reliability.This shows that the main factors of Reciprocating compressor failure is the valve and pressure packing ring fault;the second is the piston ring, piston and piston rod and the cylinder fault.The results can be used for the maintenance and improvement of reciprocating compressor design theory.
Mechanical Industry Press,1991 [7] Chen Shu-Jen , H Wang Chin G-Lai.

A check for interface failure based on the adhesive, GD414, property is done to investigate the failure behavior, also to gain a simplified interface treatment.
The results show that gaps can release the stress of the interfaces while it can’t affect the whole stress distribution too much.
Besides, to confirm the failure criterion, the paper makes an assumption that if 50% of the specific path fails, then the path fails to affect.
The whole nozzle is at a high safety factor.
Mechanical Engineer,2014,(6)

MICROSTRUCTURE AND PROPERTIES OF LASER FUSED NICKEL BASED SELF FLUXING ALLOY COATING Yu Li1,a , Kazumasa Nishio2,b , Mitsuaki Katoh 3,c and Tomiko Yamaguchi 4,d 1,2 Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, JAPAN, 3,4 Faculty of Engineering, Kyushu Institute of Technology, JAPAN, a ri-yu@edu.life.kyutech.ac.jp, bknishio@life.kyutech.ac.jp, cmkatoh@tobata.isc.kyutech.ac.jp, d yama@tobata.isc.kyutech.ac.jp Keywords: Laser fusing, sprayed coating, Ni-Cr-Si-B, wear, hot corrosion Abstract The thermal sprayed coatings are widely used in waste incineration boilers and fossil fuel-fired boilers.
Introduction Steels are the most widely used materials in construction, mechanical, tooling, aircraft and chemical industries because of their good mechanical properties and relatively low cost [1].
Moreover, the coating layers also can be peeled off because of weak mechanical bonding inherent to thermal sprayed coatings [4]; these are serious problems particularly at high temperatures and in molten salts corrosion environments.
It also can improve the protective properties and bond strength of the sprayed coatings without affecting the substrate properties and dimension with the high degree of automation and controllability of process.
The structure of coating is a key factor to affect the wear and corrosion resistances of coatings.

Thermal Mechanical Coupled 3D Finite Element Simulation of Large H-beam in Hot Rolling Process Peiqi Wanga, Qinhe Zhangb*, Baotian Dongc and Rupo Mad School of Mechanical Engineering, Shandong University, Jinan, Shandong, 250061, China alicofer4913@163.com, b*Corresponding Author: zhangqh@sdu.edu.cn, cdongbaotian@sina.cn, dmarp2005@163.com Keywords: Large H-beam, Thermal mechanical coupled, FEM, Re-meshing technique, Hot rolling Abstract.
Introduction H-beam is a kind of efficient economic cross-section profiles with wide flange, thin web, more superior cross-section properties and more reasonable ratio of strength to weight, which is more widely used.
In order to improve the accuracy of simulation, the material is tested by the Gleeble-1500 thermo-mechanical tester to get the true stress-strain data, and then the VUMAT (User-defined Material Mechanical Behavior) programme is written to define material model.
Taking into account the limit of the computer memory and stress property, the mesh is denser in the contact zone between rollers and workpiece based on subdivision method by inserting new points in the model.
The deformation and deflection of roller is an important factor for affecting the accuracy of the shape and dimension of workpiece.

The main causes of the abnormal foetal heart beats: tachycardia (mother's temperature, medicines, premature foetus, foetal anaemia and hypovolemia, imminent hypoxia and chronic acidosis, birth in pelvic presentation); bradycardia (excessive uterus activity, the rapid labour progressing, advanced pregnancy age, congenital heart block); prolonged decelerations (excessive uterus activity, maternal low blood pressure, maternal origin placenta affecting, the compression and prolapse of the umbilical cord, abruptio placentae regional anaesthesia).
Six factors which influence the thermal comfort and belong to the personal ones, as well as to the environment ones, were identified.
Environment factors: air temperature; radiant temperature; air speed; humidity.
Personal factors: clothing insulation, heat produced by the metabolism.
As a strategy of accomplishing the equipment for identifying and monitoring the personalized information, the following textile structure variants were chosen: - structures which are woven and/or knitted from yarns properties specific for ensuring the physiologic comfort, used as a flexible support for the sensor attaching; - structures which are woven and/or knitted from HiTech fibres with conductive properties.