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Controlling Pore Size of Tissue Engineering Scaffolds Fabricated by Electrospinning and Phase Separation Yu Zhou, Qilong Zhao and Min Wanga Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong amemwang@hku.hk Keywords: Electrospinning, Phase separation, Hybrid technique, Pore size, Tissue engineering scaffold.
There are different approaches in tissue engineering, including cell-based tissue engineering, factor-based tissue engineering and scaffold-based engineering.
By using different biocompatible and biodegradable polymers and controlling the electrospinning parameters (polymer solution concentration, applied voltage, solution flow rate, working distance, etc.), scaffolds with different morphology, structure and properties can be obtained.
Parameters such as polymer solution concentration and solvent for making polymer solutions were shown to affect pore sizes in nanofibrous scaffolds.
[6] Tong H W, Wang M, Electrospinning of poly (hydroxybutyrate-co-hydroxyvalerate) fibrous scaffolds for tissue engineering applications: effects of electrospinning parameters and solution properties, J.

Media was changed every 3 days and the monocytes were allowed to differentiate into functional osteoclasts over a period of 17 days cultured in complete Minimum Essential Medium (α-MEM) consisting of 10% fetal calf serum, 5µg/ml Penicillin, 50U/ml of streptomycin and 1% LGlutamine supplemented with 10 -8 M Dexamethazone, 10 -8 M Vitamin D3 and M-25ng/ml of Macrophage Colony Stimulating Factor for the first 7 days. 100ng/ml recombinant human RANKL was added for the following 10 days.The differentiated osteoclasts expressed specific osteoclasts markers like tartrate resistant acid phosphatase (TRAP) and the resorption pits on dentine indicated the functional activity of the cells.
Results and Discussion Titanium based alloys are widely used in orthopaedic implants because of their good mechanical properties.
This crystalline structure as a result of sol - gel coating technique improved the surface morphological properties and this may have a significant influence on the osteoclast behavior [13].
The changes in the surface morphology of the modified Ti-6-Al-4V induced by the osteoclast activity may affect the way osteoblasts interact with coated titanium and how bone is subsequently formed.

When the receiver is sustained at 0 K, the spectral energy flux of media 1 at distance d to the surface can be calculated by projecting the time-averaged Poynting vector[11]: (1) Here, Θ(ω, T1）is the mean energy of quantum mechanical harmonic oscillator at frequency ω, temperature T1; Z1(ω, β) can be regarded as an exchange function which provides information on the contribution to the spectral energy flux at a given β.
The reason is that when the distance is 80μm, the effect of wave interference become the dominating factor and most of radiation energy comes from evanescent waves produced by photon tunneling.
This is caused by the properties of surface waves that surface waves propagates along the interface but its amplitude decays exponentially away from surface.
Thus, the excitation frequency of surface phonon polaritons is invariant with temperature, but the intensity of polaritons is affected.
Additionally, the energy emitted by SiC increase rapidly as the temperature rises. 3)The net heat flux is revelent to optical properties of both plates.

Hydrolysis degree is one of the important indexes of polymer quality inspection, it is the important parameter that can effect polymer solution structure, rheological properties and chemical mechanical stability, which is especially important in the application of high temperature and high salt reservoir【3，4】, and it has great reference value to know the polymer form in field and further enhance oil recovery of reservoir after polymer flooding.
HPAM polymers under the condition of high temperature occurred molecular degradation and hydrolytic degradation is the main mechanism of polymer chemical degradation, and it is also the main factor that affects and limits the HPAM polymer application in high temperature and high salinity reservoir, and accurately determining the hydrolysis degree is an important basis for polymer application【5，6】.
Therefore, this article propose to do a system study to the change law of hydrolysis degree of BH heat-resistant polymer, discuss the effect of high temperature hydrolysis on the properties of BH heat-resistant polymer solution, and provides the basis of application of BH heat-resistant polymer for high temperature reservoir.

Yadav Smart Materials Research Laboratory Department of Physics, Indian Institute of Technology Roorkee, Roorkee-247667, India Email: klyadav35@yahoo.com Keywords: Ceramics, nanocomposites, X-ray diffraction, dielectric properties, magnetic properties Abstract.
The physical properties of a material that are formed from two or more singlephase compounds are determined by the properties of the constituents as well as by the interaction between them.
Magnetic properties Fig. 8 shows magnetization vs. magnetic field (M-H) hysteresis loops for the composition x = 0.2 of CFBF composite annealed at different temperatures.
This indicates that coercivity not only depend on crystallite size but some other factors also affect the coercivity, otherwise coercivity would not have decreased on further increase in annealing temperature.
Magnetoelectric properties The variation of αE=dE/dH with HBias at various magnetic frequencies is shown in Fig. 15 and Fig. 16 for CFBF and NCFBF nanocomposites, respectively.

Aiming at the thermal safety issues between the insensitive energetic plasticizer and propellant components, NG/BTTN and insensitive energetic plasticizer BuNENA plasticized propellant was compared by DSC test and cook-off numerical simulation, with the thermal safety property evaluated.
Combined excellent energy and mechanical performance, NEPE propellant has been used widely in strategic and tactical weapons, while the using of nitrate ester plasticizers such as nitroglycerine usually cause a poor insensitive property [4].
In this paper, aiming at the safety issues of the insensitive energetic plasticizer BuNENA and the and sensitive energetic plasticizer NG/BTTN, NEPE propellant plasticized by NG/BTTN and BuNENA was compared by thermal decomposition kinetics with DSC test and cook-off numerical simulation with FLUENT, and finally the thermal safety property and influencing factors of propellants were evaluated.
The Tb of NG/BTTN propellant was slightly higher than that of BuNENA propellant, indicating that two propellants showed similar thermal safety property, due to the decomposition temperature of NG/BTTN propellant was slightly higher than that of BuNENA propellant.
Different thickness of insulator affected fast cook-off simulation response.

These nano fluids exhibit good thermal properties when compared to the conventional fluids due to their possessing more surface area by virtue of existing in nano size.
The van der Waals force among the nano particles affects the stability of the nano fluids.
Properties of Nano fluids: Yu et al observed that by adding 5% of zinc dioxide nano particle to ethylene glycol, there was a 26.5% increase in the thermal conductivity.
Similarly the physical properties of the nano fluid and type of flow and turbulence in the nano movement of the nano particles had less effect on the efficiency of the radiator.
“Preparation and heat transfer properties of nanoparticle-in- transformer oil dispersions as advanced energy efficient coolants”.

It relies on applying the tools of supersymmetric quantum mechanical (SUSYQM) transform, followed by coordinate transform method and includes the effects of large internal electrostatic fields characteristic of nitride heterostructures.
These fields originate from piezoelectric and spontaneous polarization and have a very significant influence on electronic and optical properties of the structure.
Clearly, both nonlinear effects exist only in asymmetric structures (where generally 012 �
 or 031 �µ ) and their intensities are proportional to factors 12 2 12 )0( 
µ=� and 312312 )2( µµµ=� .
Evidently, SUSYQM transform produces Hamiltonians with constant effective mass and variable potential, because the variation of parameter � affects only the potential while leaving the mass intact.
In III-N compounds there exists a strong internal electric field originating from piezoelectric and spontaneous polarization [13-15], which can be as large as few MV/cm and has a considerable influence on electronic and optical properties of the structure.

Spray Characteristics of an Internal-mix Airblast Atomizer Cheng Tung Chong1,a*, Simone Hochgreb2,b 1 Faculty of Mechanical Engineering, Universiti Teknologi Malaysia 81310 Skudai, Johor, Malaysia. 2 Department of Engineering, University of Cambridge, Trumpington Street, CB2 1PZ Cambridge, UK actchong@mail.fkm.utm.my, bsimone.hochgreb@eng.cam.ac.uk Keywords: airblast, twin-fluid, atomizer, non-reacting spray, PDA Abstract.
The effect of geometry [7] and liquid properties [8-11] on the spray qualities of airblast atomizers have been studied to elucidate the primary factors involved in atomization.
Gullberg and Marklund [19] reported that fuel and geometrical properties are among the parameters that can affect spray characteristics, in a spray study using an external twin-fluid atomizer with pyrolysis oil.
Despite improved understanding of the breakup of a liquid jet by a high-speed turbulent gas jet, there is little experimental data suitable for validation regarding the spatial distribution of droplet size and velocity within the spray as a function of spray geometry and fuel properties.
The properties of the diesel fuel is reported in [1].

Introduction The material composition of cement stabilized macadam is one of the main factors which affect the compaction, thus researching on the compaction effect of cement stabilized macadam which had added fly ash and water-reducing agent under vibration compaction is important for improving compaction on the actual projects.
Since surfactant has hydrophilic and hydrophobic organic compounds in the two groups, when adding aqueous solution, these compounds can reduce the surface tension of water (water-gas phase) and interfacial tension (water - solid phase).Through adsorption - dispersion, lubrication, wetting, electrostatic repulsion, "ball bearing” effect and other s so on, it may reduce the mixing water, enhance the density of cement, improve cement pore structure and increase mixture’s strength, impermeability, freeze-thaw resistance, anti-carbonation and other properties [5].
From the above we can see that mixed additive (high-performance water-reducing agent and fly ash) can effectively improve the compaction properties of cement stabilized macadam.
[3] Xiangyang Liao, Jianjun Zi, Study on the Experiment of the Properties of Cement Stabilized Macadam with Admixtures Used in Road (Hunan Communication Science and technology, 2009(6), 13-14.), in Chinese
[4] Yubin Huang, Weimin Lv, Mechanical and Shrinkage Properties of Base Materials of Fly Ash and Cement Stabilized Crushed Rock (Highway 2006(11):145-146), in Chinese