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DILECTRIC AND THERMAL PROPERTIEs OF PEO DOPED WITH CADIMIUM CHLORIDE sALT

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Chinese Journal of Polymer science 2012年第2期30卷 143-151页

作者： Jibril Al-Hawarin Ayman s.Ayesh Rami A.Abdel-Rahem Chemistry Department College of ScienceAl Hussein Bin Talal UniversityMaanJordan Physics Department College of ScienceKing Faisal UniversityAl-AhssaKingdom of Saudi Arabia Chemistry Department College of ScienceKing Faisal UniversityAl-AhssaKingdom of Saudi Arabia

The main aim of this research is to investigate the effect of salt concentration on the dielectric properties （AC （CrAC）, permittivity （d）, dielectric loss （d＇）, and dielectric relaxation process） and melting behavior of polyethylene oxide （PEO）/CdC12 complexes. The dielectric study was carried out over a frequency range 10-335 kHz and a temperature range 25--45~C. The AC conductivity, permittivity and dielectric loss of the PEO/CdC12 complexes increase with increasing salt concentration and temperature. Also, it was found that the addition of CdC12 salt to PEO host reduced the melting temperature of PEO host. Dielectric results reveal that the relaxation process of these complexes is due to viscoelastic relaxation or non-Debye relaxation at room temperature. Additionally, it was found that relaxation behavior remained viscoelastic at different temperatures and salt concentrations.

关键词： Polyethylene oxide CdC12 salt Dielectric properties Dielectric relaxation Relaxation process Thermalproperties.

Numerical Analysis on the Effect of n-si on Cu(In, Ga)se2 Based Thin-Films for High-Performance solar Cells by 1D-sCAPs

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Gain enhancement in two-stream free electron laser with a planar wiggler and an axial guide magnetic field

Open Journal of Applied sciences（应用科学） 2024年第5期 1315页

作者： Rasika N.Mohottige Micheal Farndale Gary s.Coombs shahnoza saburhhojayeva

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Chinese Physics B 2012年第9期21卷 247-250页

作者： s.saviz Z.Rezaei Farzin M.Aghamir Plasma Physics Research Center Science and Research BranchIslamic Azad University Department of Physics University of Tehran

The theory for a two-stream free electron laser （FEL） consisting of a relativistic electron beam transported alongthe axis of a planar wiggler in the presence of an axial guiding magnetic field is proposed and investigated. The electron trajectories and the small signal gain are derived. The characteristic of the linear gain and the normalized maximum gain are studied numerically. The result shows that the normalized maximum gain is considerably enhanced in comparison with that of the single stream. The effect of the difference between the energies of the two beams in this configuration of FEL is also considered, and we find that the gain is affected by the energy differences between groups 1 and 2.

关键词： wo-stream free-electron laser

Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Heat transfer in a porous saturated wavy channel with asymmetric convective boundary conditions

林业研究（英文版） 2024年第2期 74页

作者： Aleksey s.Ilintsev Elena N.Nakvasina Alexander P.Bogdanov

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Journal of Central south University 2015年第1期22卷 392-401页

作者： Q.Hussain s.Asghar T.Hayat A.Alsaedi Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics Faculty of Science King Abdulaziz University Department of Mathematics Quaid-I-Azam University 45320

The viscous flow in a wavy channel with convective boundary conditions is investigated. The channel is filled with a porous viscous fluid. Two cases of equal and different external convection coefficients on the walls are taken into account. Effect of viscous dissipation is also considered. The governing equations are derived employing long wavelength and low Reynolds number approximations. Exact closed form solutions are obtained for the simplified equations. Important physical features for peristaltic flow caused by the wavy wave are pumping, trapping and heat transfer rate at the channel walls. These are discussed one by one in depth and detail through graphical illustrations. special attention has been given to the effects of convective boundary conditions. The results show that for Bi1≠Bi2, there exists a critical value of Brinkman number Brc at which the temperatures of both the walls become equal. And, for Bi1>Bi2 and Br>Brc, the temperature of the cold wall exceeds the temperature of hot wall.

关键词： peristalsis heat transfer porous medium convective boundary conditions

Nanophase Decomposition of a Zn-Al Based Alloy Zn_(68)Al_(10)Cu_(22)

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Journal of Materials science & Technology 2004年第6期20卷 687-690页

作者： Y.H.Zhu W.B.Lee s.To Advanced Materials Research Center Department of Industrial and systems Engineering The Hong Kong Polytechnic University Hong Kong ChinaAdvanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong ChinaAdvanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China

The nanostructural evolution and phase transformation of the films of a Zn-Al based alloy (Zn68Al10Cu22 in wt pct) have been studied by using X-ray diffraction and scanning electron microscopy. Nanostructural thin films of the Zn-AI based alloy were produced by using an electron beam deposition technique. It was found that a nanocrystalline phase η'n had a strong preferred crystal orientation at (0002) crystal planes in the as-deposited films. During ageing at 220℃, the decomposition of nanophase η'n started with clustering to form Z-zones, and transitionai phase, which was accompanied by an eutectoid decomposition of the η'n phase: η'n β'eut T'. Decomposition, such as clustering and the formation of the Z-zones, and the transitionai phase etc. were observed in the nanophase β'eut. The formation and the decomposition of the transitionai phase of micrometers in size were involved in the decomposition of the main nanophase η'n. The mechanism of the Z-zones formation and the stability of nanophases were discussed.

关键词： Ageing Nanostructure Nanophase stability Zn-Al based alloy film

A case for systemic environmental analysis of cultured meat

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Journal of Integrative Agriculture 2015年第2期14卷 249-254页

作者： Carolyn s Mattick Amy E Landis Braden R Allenby University of Texas school of Public Health 1200 Hermann Pressler DriveHouston TX 77030 USA school of sustainable Engineering and the Built Environment Arizona State UniversityTempe AZ PO Box 875306 USA

The environmental implications of cultured meat are profound. An anticipatory life cycle assessment of cultured meat published in 2011 suggested it could have a smaller impact than agricultural meat in all categories except energy consumption. As with most technologies, cultured meat will almost certainly be accompanied by unintended consequences as well as unforeseen costs and benefits that accrue disproportionately to different stakeholders. Uncertainty associated with new engineered products cannot be completely eliminated prior to introduction, but ongoing environmental assessments of the technologies as they advance can serve to reduce unforeseen risks. Given the pace at which tissue engineering is advancing, systemic assessments of the technology will be pivotal in mitigating unintended environmental consequences.

关键词： cultured meat in vitro meat factory-grown food anticipatory life cycle assessment systemic environmental implications of emerging technologies

Creep Behavior and Microstructure Evolution of sand–Cast Mg–4Y–2.3Nd–1Gd–0.6Zr Alloy Crept at 523–573 K

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Journal of Materials science & Technology 2017年第1期33卷 79-89页

作者： Y.H.Kang H.Yan R.s.Chen The Group of Magnesium Alloys and Their Applications Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China University of the Chinese Academy of sciences Beijing 100049China

High temperature tensile-creep behavior of Mg-4Y-2.3Nd-IGd-O.6Zr （wt%, WE43（T6）） alloy at 523- 573 K was investigated. The creep stress exponent is equal to 4.6, suggesting the underlying dislocation creep mechanism. The activation energy is （199 _＋ 23） kJ/mol, which is higher than that for self- diffusion in Mg and is believed to be associated with precipitates coarsening or cross slip. The creep mechanism is further suggested to be dislocation climb at 523 K, while a cross slip at 573 K is possible. The metastable 13＇ and ~]1 phases in the WE43（T6） alloy were relatively thermal stable at 523 K and could be effective to hinder the dislocation climb, which contributed to its excellent creep resistance. However, at 573 K it readily transforms into equilibrium/3e phase and coarsens within two hours, thereby causing a decrease of creep resistance. In addition, precipitate free zones approximately normal to applied stress direction （directional PFZs） developed during the creep deformation, especially at 573 K. Those zones became preferential sites to nucleate, extend and connect microcracks and cavities, which lead to the intergranular creep fracture. Improving the thermal stability of precipitates or introducing thermally stable fine plate-shaped precipitates on the basal planes of Mg matrix could enhance the high temperature creep resistance.

关键词： WE43 alloy Creep PFZs Precipitate Fracture

Mechanical behavior of Cu-Zr bulk metallic glasses (BMGs): A molecular dynamics approach

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Chinese Physics B 2013年第9期22卷 490-495页

作者： Muhammad Imran Fayyaz Hussain Muhammad Rashid Yongqing Cai s.A.Ahmad Department of Physics simulation Lab The Islamia University of Bahawalpur Department of Physics National University of Singapore2 Science Drive 3117542Singapore

In the present work, three-dimensional molecular dynamics simulation is carried out to elucidate the nanoinden- tation behaviors of CuZr Bulk metallic glasses （BMGs）. The substrate indenter system is modeled using hybrid interatomic potentials including both many-body Finnis sinclair （Fs） and two-body Morse potentials. A spherical rigid indenter （diameter= 60 A（1 A = 10 ^-10 m）） is employed to simulate the indentation process. Three samples of BMGs including Cu25Zr75, CusoZr50, and Cu75Zr25 are designed and the metallic glasses are formed by rapid cooling from the melt state at about 2000 K. The radial distribution functions are analyzed to reveal the dynamical evolution of the structure of the atoms with different compositions and different cooling rates. The mechanical behavior can be well understood in terms of load-depth curves and Hardness-depth curves during the nanoindentation process. Our results indicate a positive linear relationship between the hardness and the Cu concentration of the BMG sample. To reveal the importance of cooling rate provided during the processing of BMGs, we investigate the indentation behaviors of CusoZr50 at three different quenching rates. Nanoindentation results and radial distribution function （RDF） curves at room temperature indicate that a sample can be made harder and more stable by slowing down the quenching rate.

关键词： Bulk metallic glasses (BMGs) nanoindentation deformation quenching rate