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The traditional methods of oil-gas separation such as vacuum method and mechanical oscillation method were unable to satisfy the requirements of transformer on-line monitoring; and the methods which were used commonly in recent years, like dynamic headspace separation, corrugated tube, carrier gas elution etc, have a high rate of gas-separation and have already been used in some on-line monitoring products.
Introduction Large transformer is one of the most important equipment in power industry, the reliable operation of transformer ensure the safety of electricity supply, and greatly affect national economic development and people's livelihood.
DGA can diagnose internal transformer fault regularly during the transformer operation, and will not be affected by external electromagnetic fields [4], is an effective technique which has been widely used to detect latent faults in transformer, and oil-gas permeability technology is just the important prerequisite and key technology to achieve the requirements of DGA.
After setting complete, the formed mixed hollow fiber membrane has its own structural features: the surface layer has good permselectivity which is very thin (about several tens of nanometers thick), so has improved the mixed hollow fiber membrane permeability on dissolved gas in transformer oil; the lower layer is support layer which is more than 100 microns thick, and there are many pores in moderate size on the lower layer, which make the mixed hollow fiber membrane has good mechanical properties and pressure resistance.
If the material is certain, the main factors to affect the separation performance are membrane thickness and permeation area of membrane.

It is reported that the mechanical properties such as yield strength, ultimate tensile strength and elastic modulus increase with increase in filler content while ductility decrease with the addition Ti reinforced in alloy matrix.
The input control factors and there values are listed in Table 2.
Effect of control factors on wear rate for Ti filled Al7075 alloy composites.
Elaya Perumal, Influence of B4C on the tribological and mechanical properties of Al 7075–B4C Composites, Composites.
Ranganathan, Evaluation of mechanical and wear properties of hybrid aluminium matrix composites, Trans.

The reasonable cable force is the key factor for the safe use of cable-stayed bridge.
Introduction Since the 20th Century, the cable-stayed bridge obtained rapid development at home and abroad with its appealing design, great mechanical behavior and long spanning capacity, etc.
Cable-stayed bridge has complexity mechanical behavior as a high-order hyper-static structure.
As the main load-bearing structure, whether the reasonable of cable force directly affect the safety, serviceability and durability of structures in completed and used stage.
Method of continuous beam on rigid supports: Under the status of the completed bridge, the internal force of the mechanical properties of cable-stayed bridge girder as same as the continuous beam with rigid supports.

Recent studies have showed that their morphology had a strong influence on their optical and electrical properties.
The reports showed that both shape and size of the MNPs were key factors determining incoupling efficiency.
Gurunathan, Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches, Int.
Maier, Optical and Structural Properties of Ultra-thin Gold Films, Adv.
Huo, Poly(acrylic acid)-stabilized colloidal gold nanoparticles: synthesis and properties, Nanotechnology 21 (2010) 455702 [13] C.

In order to investigate the mechanical properties of concrete beams strengthened with CFRP sheets under load conditions, according to the reinforcement ratio, three groups of twelve concrete beams were made, each group included an common concrete beam and three prestressed CFRP sheets reinforced beams.
In Table 3, the curvature ductility parameter of YJGL1-A, YJGL2-A were 3.9 and 3.0，their ductility were great, the curvature ductility parameter of YJGL1-C, YJGL2-C reduced to 2.3 and 2.0, and the curvature ductility factor of DBL-1, DBL-2 were 1.5 and 1.8, the ductility of beam can be improved with CFRP sheets reinforced, different levels have a major influence to the ductility of the beam.
In Design process, we should control the prestress level properly and make the specimens with prestressed CFRP reinforcement with good ductility properties.
The analysis showed that: concrete beam in the case of holding charge, normal section reinforcement with prestressed CFRP sheet had not affect to the performance of the secondary force, the reinforcement effect was still very obvious under load.

In this way, the analyte in all air holes is detected which can be affected through the evanescent field.
The energy overlap factor is defined as the percentage of energy propagating in the six big holes with respect to total mode energy.
The energy overlap factor is 0.00389 when holes are filled with air, and that is 0.0121 when holes are filled with water.
The optical properties of the PCF has been studied and some future design also been proposed especially on the biosensing performance, which can potentially operate on biochemical detecting applications and is useful for improving higher sensitivity.
Pei, Gas sensing properties of index-guided PCF with air-core, Optics & Laser Technology. 40 (2008) 167-174.

The results reveal that the fiber orientation angle is the most significant factor affecting the dynamic characteristics of CFRP/Metal hybrid shaft.
This is due to its good inherent mechanical properties such as high specific strength (strength/density), high specific modulus (modulus/density), high temperature resistance and low coefficient of thermal expansion [4-7].
Mechanical properties of 45 steel.
Properties of carbon fiber epoxy composites.
From Fig. 9, the relationship between the bending natural frequency and the fiber orientation angle is nonlinear because the orthotropic material properties of CFRP.

Kinematic optimization of a new high-speed press using a GA-DE algorithm Xi-Yang Sun1,a, Shuan-Hu Wang2,b 1,2School of Mechanical Engineering, Nanjing University of Science and Technology, Xiaolingwei 200, Nanjing, Jiangsu Province, China aSunyang.89@163.com, bshuanhuwang@tom.com Keywords: Kinematic optimization; High-speed press; GA-DE algorithm Abstract: The objective of this paper is to implement the optimal design of a high-speed press with a new transmission mechanism for punching.
Given this, the longer crank length is, the larger resisting arm affecting the transmission becomes.
Therefore, crank length, as one of important factors influencing motion property of high-speed press, is taken as the optimal object.

After mechanical polishing, the specimens were annealed in a vacuum at 600 0C for 30 minutes before a chemicalpolishing to remove any oxidation and mechanical surface damages.
Lattice rotation near high angle grain boundary is small, while lattice rotation near low angle grain boundary is large, suggests that grain boundaries and grain orientations can affect the slip behavior.
In order to calculate to the elastic stress at an early deformation stage, we simply assumed that the mass within a grain is continuum and the mechanical properties of one grain depend on crystallographic orientation and can be calculated by the Eq. (1), where α, β, and γ are the direction cosines[5].
This result can be explained that the grain boundary property is more important factor for plastic deformation than the elastic stress in early deformation stage. 4.
The elastic stress in an early deformation stage was also calculated by using an FEM simulation, but the effect appears to be minor compared to the grain boundary properties.

Many research groups have focussed upon the improved mechanical properties of UFG materials compared with the coarse-grained (CG) counterpart [1].
From the mechanical point of view UFG-HT offers the most promising combination of high-strength with moderate ductility [9].
The same tendency can be deduced from the pit densities affected by ECAP and the modified condition, too.
In fact, [5] presents worse corrosion properties of the ECAP material Al99.99 compared to the CG material.
Furthermore, these NC and dislocation density were enhanced in the UFG-HT condition although the corrosion properties are not decreased.