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., Japan) were studied to determine mechanical properties, volume change ratio, and force generation characteristics of the PAN gel fibers for both chemically-driven and electrically-driven systems [4], no systematic studies for the as-spun PAN fibers and the PAN gel fibers was performed.
Morphology of the as-spun PAN fibers prior to the activation of the PAN gel fibers and chemomechanical properties of the PAN gel fibers, the subject of this study, were carried out to evaluate the effects of experimental parameters on morphology of the as-spun fibers and the influence of pH sensitivity on dimensional change of the PAN gel fibers.
Results and discussion The properties of different concentrations of polymer solutions are given in Table 1.
Properties of the PAN/ DMF solution Spherical or spindle-type beads were observed for the electrospun fibers at viscosities ranging from 46 to 1000 cP (PAN concentrations from 4 to 9 wt%).
It is reported that viscosity and surface tension of the precursor solution affect the formation of beads.

Study on the Mechanical Properties and Heavy Metal Ions Immobilization Capability of Solidified Body for MSWI Fly Ash with Geopolymer Qing Wang1,a, Xinrui Wang1,b, Hai Cao1,c, Zhaoyang Ding1,d, Deyong Kong2,3,e* 1School of Material Science and Engineering, Shenyang Jianzhu University, Shenyang, 110168, China 2Liaoning Hai Tian Ge Environmental Protection Technology Co., Ltd, Fushun, 113000, China 3Shenyang Academy of Environmental Sciences, Shenyang, 110167, China awangqingmxy@126.com, b994987029@qq.com, c125856093@qq.com, dsmallnew69@126.com, ekongdeyong0453@163.com Keywords: MSWI fly ash; Geopolymer; Solidified body; Single-component; Heavy metal ions Abstract.
Geopolymer is significantly different from ordinary Portland cement in terms of structural properties and reaction mechanism [4].
Through the analysis of the infrared spectrum, it can be concluded that the heavy metal ions contained in MSWI fly ash will not affect the [SiO4] and [AlO4] tetrahedral structure, but be participated in the actual reaction in some form.
Shi, Effect factors and mechanism of solidification/stabilization of heavy metals by geopolymers: Journal of Functional Materials, 5(2015),5013-5018
Zhang, Preparation properties and mechanism of slag based geopolymer: Journal of Wuhan University of Technology, 31(2009),120-125

So it is the key factor to take effective tunnel surrounding control technology for safety and effect of isolated island coal face.
Mechanical model and mechanical parameters.
With Mohr-Coulomb yield criterion to judge the damage of rock mass, the rock mechanical property parameters of coal rock mass model is shown in table 1.
Table 1 Coal petrography mechanical parameters lithology Thickness （m） Shear modulus （GPa） Bulk modulus (GPa) Cohesion (MPa) Internal Friction angle（°） Density (kg/m3) mudstone 7.2 3.47 6.08 3.5 30 2472 13-2 coal 0.9 2.01 4.9 1.25 28 1380 Chiltern mudstone 6.5 5.37 8.23 4.5 33 2472 13-1 coal 3.4 2.01 4.9 1.25 28 1380 Silt finestone 1.3 9.62 14.33 8.31 38 2520 Table 2 Rock mass mechanics parameters after slip casting reinforced Bulk modulus（GPa） Shear Modulus （GPa） Density （kg/m3） Internal Friction angle（º） Cohesion （MPa） Tensile Strength （MPa） 1.257 5.80 2243 29 1.0E6 0.83E6 Characteristic of surrounding rock stress.
It is shown as Fig.4 that bolt is affected by tension stress and bolt cable by pressure stress in bolt cable-mesh support.

The produced fusion weld as an integral part of the whole cast is one of the factors determining its functional properties.
Chemical composition and properties of the QE22 alloy.
Acknowledgements The study has been financed within the project N N507 244240 “Structure and properties of welded joints of cast magnesium alloys in simulated operating conditions”.
Rzychoń, Magnesium Alloy – microstructure, properties and applications in: W.
Kiełbus, Structure and mechanical properties of casting MSR-B magnesium alloy, JAMME 18 (2006) 131-134

Sodium hypophosphite (NaH2PO2) is the most atom-efficient reactant to fulfill the alkylation process [3], with inexpensive and environmentally benign properties has been widely used [4].
They have too similar aqueous solubility to separate, which will sharply affect each other performances when coexisting in production [6].
The aluminum diethylphosphinate, which have high P % and thermal stability，can significantly decrease the flammability in glass-fibre renforced polyamide 6.6 [13].It is a halogen-free flame retardant, with excellent flame retarding, electric, mechanical properties, good ecologically toxic evaluation, and regenerated properties[14].
So the temperature was a critical factor.

Corrections Commercial software Simerics was used to get the correction factors of Reynolds number and Mach number, the simplified CFD calculation model is shown in Fig. 2.
Correction factors are derived according to the length and diameter ratio L/D and the ratio of chamfering depth and diameter c/D for chamfered inlet, or the ratio of radiusing dimension and diameter r/D for radiused inlet.
The correction factors of CRL, CRr and CRc in different working conditions are shown in Fig. 8 to 10.
The factors considered in the model is comparable comprehensive, it can simulate laminar flow state with low Reynolds number and complex working conditions of rotation, high mach number flow and supersonic flow.
Journal of mechanical engineering science, 7(2), pp. 210-219.

Thus, wood material polysaccharides exhibit amphoteric properties, forming salts with alkali metal solutions, which characterizes wood material as a weak organic solid acid.
The use of phosphorus compounds is due to the properties of inhibitors of the radical-chain reaction of combustion.
In the conditions of providing fire-retardant properties of wood material, the interaction with inorganic acid will also be predominant.
To give the surface of the sample the properties of conductivity, ion sputtering of the metal under vacuum conditions was used.
Flame retardancy and thermal degradation properties of polypropylene/wood flour composite modified with aluminum hypophosphite/melamine cyanurate.

Introduction Owing to the high mechanical properties and the good weld ability, low cost et al, aluminum-magnesium alloy have a wide application in aviation, shipbuilding, nuclear industry and weapons [1].
However, aluminum-magnesium alloys are non-heat treatable alloys, the micro alloying and hardening are the main methods to improve the properties of these alloys [2].
The results showed that added of element erbium can well improve not only the strength, plasticity, but also the corrosion resistance and fatigue properties of the alloys [6-8].
Deformation temperature is an important factor which will affect the flow stress.

If motors of out of step have large number, their dynamic process will affect the stability of system.
Dynamic characteristics of motor under disturbance Rotor motion equation of induction motor: (1) Where: is mechanical torque which , is electromagnetic torque,.The slip corresponding the maximum electromagnetic torque is .
Therefore, according to the slip coherent properties, it is need to divide into motors in normal operation and motors of out of step for load modeling.
The paper set the static load and motor mechanical load factor as typical parameters,only identifying the parameters as follows:,The limit of the parameters are,,,,,,,; Load parameter identification is a optimization process, which hope to find a set of optimal parameters to make the model’s response be possible consistent with the actual measurement process.

NUMERICAL ANALYSIS OF NATURAL CONVECTIVE HEAT TRANSFER OVER A VERTICAL CYLINDER USING EXTERNAL FINS Anwesha Panigrahi1,a*, D.P.Mishra2,b, Deepak Kumar3,c 1,2,3 Department of Mechanical Engineering Birla Institute of Technology, Mesra, Ranchi-835215, Jharkhand, India aanwesha199021@gmail.com, bdpmishra@bitmesra.ac.in, cdeepak.bit2013@gmail.com, Keywords: Natural convection, Fins, Cylinder, Nusselt number Abstract The present numerical study deals with the natural convection heat transfer on the surface of a vertical cylinder with external longitudinal fins.
The addition of fins increases the surface area and also rate of heat transfer but the increment is up to a certain limit beyond which they will resist the air flow and cause boundary layer interference that will e\affect the heat transfer adversely.
Water at supercritical pressure has a distinct feature of creating the natural convection in it due to buoyancy forces because of the difference in densities at different points of its flow cross section and this factor exerts an influence of the process of heat transfer in the core of the nuclear reactor.
The fluid properties are constant except density which is a function of temperature. 4.
[5] Leung C.W., et al., “Heat Exchanger Design: Thermal Performances of Rectangular Fins Protruding from Vertical or Horizontal Rectangular Bases”, Applied Energy, 123-140, (1985) [6] Yüncü H. and Güvenc A., “An Experimental Investigation on Performance of Rectangular Fins on a Vertical Base in Free Convection Heat Transfer”, Heat and Mass Transfer, 409-416, (2001) [7] Yüncü H. and Mobedi M., “A Three Dimensional Numerical Study on Natural Convection Heat Transfer from Short Horizontal Rectangular Fin Array”, Heat and Mass Transfer, (2003) [8]Jeong et al., “Natural convection heat transfer estimation from a longitudinally finned vertical pipe using CFD”, Mechanical Science and Technology, 1517-1527, (2009) [9] A.