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Results show that processing temperature is a key factor as intensity of the N1s peak increases gradually while processing temperature improves, furthermore, when temperature is 175℃, the most intensity of the N1s peak is obtained.
Introduction The mechanical properties of carbon fiber composites are dependent on the properties of the carbon fiber and the matrix, and the effectiveness of the interfacial adhesion between the carbon fiber and the matrix.
(a) (b) (c) (d) Fig.1 XPS survey spectra of carbon fibers (a)untreated ,(b) 1#,(c) 2#,(d) 3# Table 2 XPS surface element analysis data Element/At.% C1s O1s N1s Si2p O1s /C1s N1s /C1s Si2p/C1s Untreated 70.31 18.57 1.05 10.08 0.26 0.02 0.14 1# 70.2 16.05 7.29 5.28 0.23 0.10 0.08 2# 70.89 16.68 6.23 3.63 0.24 0.09 0.05 3# 74.47 11.94 9.71 2.33 0.16 0.13 0.03 Obviously, temperature is the main factor that affects the oxidation degree.
Although we have not yet understood the interaction between treatment parameters and fiber by present theoretical research and device, it can be confirmed that processing time is an important factor for that.

Depending on the chemical components of binder used, significant differences arise in the physical and mechanical properties of polymer concrete.
References [1] Ohama, Y., Demura, O., Mix proportioning and mechanical properties of polymethyl methacrylate resin concrete, Transactions of the Japan Concrete Institute, 3,(1981) 441-448
H., Mechanical properties of acrylic polymer concrete containing methacrylic acid as an additive", Construction and Building Materials, 37, (2012) 669-679
R., Factors affecting the curing and strength of polymer concrete, Journal of the American Concrete Institute, 80(5), (1983) 396-402
[6] Kobayashi, T. and Ohama, Y., Low-temperature curing of polymethyl methacrylate polymer concrete, Transportation Research Record 1003, International Symposium on Mechanical Properties of Special Concrete, (1984) 15-18

Type of aggregate affected the CTE significantly.
Besides concrete ages, there are many factors [5] known for affecting the coefficient of thermal expansion of concrete, including the types of coarse aggregates, relative humidity, admixtures, outline of specimen, etc.
Table 1 presents the sources and main properties of these coarse aggregates.
The mixing was further continued for about two minutes before evaluating the fresh concrete properties, for example, the slump, air-content, and density.
Results and analysis Fresh properties tests for concrete mixtures were conducted in accordance with the ASTM standards and the results are given in Table 4.

aa.chahardehi@cranfield.ac.uk Keywords: CO2 Transport Pipelines, Structural Integrity, Stress Intensity Factor, Toughness, Ductile Failure, Brittle Failure, Crack Propagation.
A critical part of the structural integrity model should deal with the arrest and initiation stress intensity factors; Gray et al. have conducted tests on mild steels and demonstrated that the two values are identical in sub zero temperatures [23].
This type of test, modified to account for the requirements of CO2 pipelines in terms of steel type, thickness and geometry constraint, can be used as a tool in the generation of the material property database.
[6] W.A Maxey, Factors Affecting Ductile Fracture in Offshore Gas Pipelines, Proceedings of the Offshore Technology Conference, OTC4241, 14th Annual OTC, May 1982, Houston, USA
Priest, The Arrest of Propagating Cracks, Practical Applications of Fracture Mechanics to Pressure Vessel Technology, Institution of Mechanical Engineers, 1971

Critical stress/strain is an important parameter to describe the transport property of superconductors under mechanical stress.
Thus, it is indispensable to study the transport property of superconductive wires under mechanical stress/strain.
Here the electrical transport property of copper reinforced Bi-2223/Ag tape under mechanical tensile stress was studied at 77 K.
Thus, when the mechanical property in HTS tapes is studied, the random of choosing samples should be also considered.
The further study will be needed on the relationship between the mechanical property of HTS tape and the mechanical property of its components to locate the critical stress/strain in the stress-strain curve.

It was also observed that different input parameters have pronounced affect on the formation of oxide scale inside the steam generator tube.
It was also observed that due to formation of scale the thermal conductivity in the boiler tubes was affected and the remaining life of boiler tubes was decreased and accelerated creep damage.
The trend was same for all the models, however the affect was more severe with the increase of both the flue gas and steam temperature.
As stated earlier, the building of scale around the inside wall of the tube causes a layer of material with different thermal properties compared to the original wall itself.
One of the controlling factors for the development of scale is the effect of temperature as shown in Fig 3.

Abdullah3,e 1 Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang Selangor, Malaysia. 2 Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, 43400 UPM, Serdang Selangor, Malaysia. 3 Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, Bangi, 43600 UKM Bangi, Selangor, Malaysia.
Indeed, many methods have been developed to describe the life time behavior under thermo-mechanical, especially with the latest, thermo-mechanical fatigue life assessment of aluminium components using Sehitoglu model [1].
In short, it is evident that the temperature is one of the major factors that affect the fatigue characteristic specifically the fatigue strength of low carbon steel or any other materials.
Due to material properties are sensitive to variation of temperature therefore temperature was accurately controlled by electrical thermocouple with tolerance of ± 2°C.
Temperature affects on fatigue behavior are shown in this figure regarding changes in position of data collected by similar stress ratio.

After a long time running, the parts of metro vehicles will have a certain degree of wear and fear and aging, the car body’s bottom include running gear, dynamo, electrical cabinets and so on will be deposited amount of dust; these things will affect vehicle's property and service life, lead to accidents.
In the dust generation process, what plays a decisive role is the air flow speed, not mechanical force, gravity or other forces.
The dust has five properties include adhesion, cohesion, charge, flammability and water absorption.
These dusts are attached to the running gear, motors and electrical cabinets in metro’s bottom, as time passes, the dusts become more and more, and they are enough to affect the normal driving of the vehicle.
Parameter of the air compressors and vacuum cleaner was selected by the calculated data, and then multiply the safety factor to ensure dusts can be inhaled in the pipelines.

Electrostatic enhancement of coalescence is to apply a high electric field to the flowing emulsion to affect coalescence.
The effect of electrostatic enhancing coalescence depend on several factors, such as the electric field[2,3,4,7,8], the frequency[2,3], electrode design and coating[2,3], drop size[3,5], water cut[3,6,7], hydrodynamic conditions (flow rate, turbulence, residence time)[3,7,8] and crude oil composition and presence of surfactants[3,6,9].
Moreover, the simulation results are used to study the main factors on coalescence of droplets.
The important properties of the liquids are given in Table 1.
Table 1 The properties of the liquids used in the experiments Liquids Conductivity (µS m-1) Viscosity (Pa s) Surface tension (mN m-1) Density (kg m-3) Dielectric constant Distilled water 4.0×10-4 1.0 72 998 80 Kerosene+2%asphaltene 1.6×10-14 0.92 24.5 802.0 2.2 It is mainly paid attention that the electric force affects the motion of the droplets in stationary oil.

However, PMLSM is more easily affected by load disturbance, force ripple and parameter variation.
Dynamic performance is very important index for direct drive, which affects the capability of CNC machines tools.
This will affect the cutting precision and surface quality directly [5].
The property of dynamic disturbance rejection is called dynamic stiffness which is defined as the change in output displacementwith respect to per unit disturbance force [9].
Dynamic stiffness is the most important factor for CNC machine tool servo consideration.