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The Synthetic and mechanical Properties of a Silica Matrix Cermet Composite

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 423-428页

作者： Sufian h humeedi Saadoon M Abdulkareem Salih Y Darweesh Department of Physics College of ScienceTikrit UniversityTikritIraq Physics Department College of EducationSamaraa UniversitySamaraaIraq Physics Department College of Education TuzKhurmatuTikrit UniversityTikritIraq

A cermet composite was prepared by employing th.rmal spraying flame onto stainless steel surfaces of(304)*** 25,50%of aluminum was mixed with matrix of(10%Al_(2)O_(3)-SiO_(2)).A spray system consistis of oxygen barrel,acetylene and spray gun that contains powders feeder at different spray distances(5,10,15,20 and 25 cm).The th.rmal treatment of the samples resulting from spraying was performed at 1100℃for 1.5 *** physical examinations(porosity and adhesion),mechanical tests(h.rdness and wear rate)and Atomic Force Microscope(AFM)test were performed before and after th.rmal *** test results showed that the best mixing rate was(50%)and the best spray distance was(15cm)wh.re the quality of coating layer improved after th.rmal treatment at 1100℃for 1.5 hr with a porosity ratio reduced from 11.2%to 6.6%,and adhesion strength improved with the increase in the alumina content to 50%.The results demonstrated that the best adhesion value after th.rmal treatment was 30.98 *** h.rdness of coating layer increased from 45.78 to 54.88 hV;while the lowest rate of wear was at 50%of alumina with a spray distance of ***,th.re was a clear improvement based on AFM within grain size,root mean square and roughness rate.

关键词： spraying by flame ceramic oxides composites atomic force microscope

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细粒六硝基芪冲击起爆模型

火工情报 1992年第1期 74-83页

作者： Kipp,me 符绿化

Influence of particle size and temperature on the dielectric properties of CoFe_2O_4 nanoparticles

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International Journal of Minerals,metallurgy and Materials 2014年第4期21卷 408-414页

作者： Deepshikha rath.re rajnish Kurchania r.K.Pandey NIIT University Department of Physics Maulana Azad National Institute of Technology (MANIT)

The objective of this study was to establish the dielectric properties of CoFe2O4 nanoparticles with particle sizes that varied from 28.6 to 5.8 nm. CoFe2O4 nanoparticles were synthesized using a chemical coprecipitation method. The particle sizes were calculated accord-ing to the Sch.rrer formula using X-ray diffraction （XrD） peaks, and the particle size distribution curves were constructed by using field-emission scanning electron microscopy （FESEM） images. The dielectric permittivity and loss tangents of the samples were determined in the frequency range of 1 khz to 1 Mhz and in the temperature range of 300 to 10 K. Both the dielectric permittivity and the loss tangent were found to decrease with increasing frequency and decreasing temperature. For the smallest CoFe2O4 nanoparticle size, the dielectric per-mittivity and loss tangent exhibited their highest and lowest values, respectively. This behavior is very useful for materials used in devices that operate in the microwave or radio frequency ranges.

关键词： cobalt ferrite nanoparticles coprecipitation dielectric properties permittivity loss tangent particle size temperature

Is activation of GDNF/rET signaling the answer for successful treatment of Parkinson's disease?A discussion of data from the culture dish to the clinic

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Neural regeneration research 2022年第7期17卷 1462-1467页

作者： James A.Conway Edgar r.Kramer Institute of Translational and Stratified medicine Peninsula Medical SchoolFaculty of HealthUniversity of PlymouthDevonUK

The neurotrophic signaling of glial cell line-derived neurotrophic factor(GDNF)with its canonical receptor,the receptor tyrosine kinase rET,coupled togeth.r with the GDNF family receptor alpha 1 is important for dopaminergic neuron survival and physiology in cell culture experiments and animal *** prompted the idea to try GDNF/rET signaling as a th.rapeutic approach to treat Parkinson’s disease with the hallmark of dopaminergic cell death in the substantia nigra of the *** several clinical trials with GDNF in Parkinson’s disease patients,which mainly focused on optimizing the GDNF delivery technique,benefits were only seen in a few *** general,the endpoints did not show significant *** suggests that it will be helpful to learn more about the basic biology of this fascinating but complicated GDNF/rET signaling system in the dopaminergic midbrain and about recent developments in the field to facilitate its use in the *** we will refer to the latest publications and point out important open questions in the field.

关键词： α-synuclein clinical trials dopaminergic neurons glial cell line-derived neurotrophic factor GFrα1 gut-brain axis Nedd4 Parkin Parkinson’s disease rET

Simultaneous effects of chemical reaction and Ohmic heating with heat and mass transfer over a stretching surface: A numerical study

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1137-1142页

作者： S.r.Mishra M.M.Bhatti Department of Mathematics Siksha ‘O’ Anusandhan University Shanghai Institute of Applied Mathematics and mechanics Shanghai University

In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics reynolds number. The governing flow problem comprises of momentum, continuity, th.rmal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method(SLM) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sh.rwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology.

关键词： Ohmic heating heat and mass transfer Chemical reaction Successive linearization method

Experimental Investigation of Micro heat Pipes of Different Cross-Sections having Same hydraulic Diameter

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Journal of Th.rmal Science 2008年第3期17卷 247-252页

作者： S.L.Mahmood M.A.r.Akhanda Department of mechanical and Chemical Engineering Islamic University of Technology

Effects of micro heat pipe （MhP） cross-sections and orientations on its th.rmal performance are experimentally investigated in this study. Tests are conducted using five different cross-sections （circular, semicircular, elliptical, semi-elliptical and rectangular） of micro heat pipes having same hydraulic diameter of 3 rnm placed at three different inclination angles （0°, 45°, 90°）, wh.re water is used as the working fluid. Evaporator section of the MhP is heated by an electric heater and the condenser section is cooled by circulation of water in an annular space between condenser section and the water jacket. Temperatures at different locations of the MhP are measured using five calibrated K type th.rmocouples. heat supply is varied using a voltage regulator which is measured by a precision ammeter and a voltmeter. It is found that th.rmal performance tends to deteriorate as the MhP is flattened. Thus among all cross-sections of MhP, circular one exhibits the best th.rmal performance in terms of heat flux dissipation followed by semi-elliptical, semi-circular, elliptical and rectangular cross-sections. Moreover, its heat transfer capability also decreases with decreasing of its inclination angle. Finally, a correlation is developed which covers all the experimental data within ＋7%.

关键词： Micro heat pipe cross-section hydraulic diameter inclination.

Sustainable Development and Strategic Thinking

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Chinese Journal of Population,resources and Environment 2007年第4期5卷 3-19页

作者： Walter r Stahel School of Engineering University of Surrey CH-1211 Geneva 3

From an economic point of view, the industrial econ- omy is efficient to overcome situations of a scarcity of goods. From a technological point of view, the resource efficiency of the manufacturing processes of the industrial economy has been per- manently improved during the last 200 years. In addition, cleaner processes have been developed. however, from an ecologic point of view, an increasing world population with increasing consump- tion has produced a "global footprint" which approaches the car- rying capacity of the planet. A circular economy and its high-value spin-offs-a lake economy and a performance or functional service economy-can fulfil customers' needs with considerably less resource consump- tion, less environmental impairment in production and considera- bly less end-of-life product waste, especially in situations of af- fluence, when a considerable stock of physical goods and infra- structures exists. Also, in situations of a scarcity of natural resources, both en- ergy and materials, often ch.racterised by rapidly rising resource prices, the economic actors of a circular economy have a high competitive advantage over the actors of the industrial economy, due to much lower procurement costs for materials and energy. From a social point of view, a circular economy increases the number of skilled jobs in regional enterprises. however, the shift from a linear manufacturing economy to a circular or service economy means a change in economic thinking, from flow (throughput) management to stock (asset) management: in a manufacturing economy with largely unsaturated markets, total wealth increases through accumulation as resource through- put (flow) is transformed into a high.r stock of goods of better quality (but in a manufacturing economy with largely saturated markets, wealth.represented by the stock of goods will no longer increase); in a circular or service economy, total wealth increases through a smart management of existing physical assets (stock

关键词： sustainable development circle economy

Subwavelength grating devices in silicon photonics

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Science Bulletin 2016年第11期61卷 879-888页

作者： Junjia Wang Ivan Glesk Lawrence r.Chen Department of Electrical and Computer Engineering Mc Gill University Department of Electronic and Electrical Engineering University of Strathclyde

Subwavelength grating(SWG) waveguides in silicon-on-insulator are emerging as an enabling technology for implementing compact, high-performance photonic integrated devices and circuits for signal processing and sensing applications. We provide an overview of our recent work on developing wavelength selective SWG waveguide filters based on Bragg gratings and ring resonators, as well as optical delay lines. These components increase the SWG waveguide component toolbox and can be used to realize more complex photonic integrated circuits with enhanced or new functionality.

关键词： Subwavelength gratings Siliconphotonics Integrated optics - Bragg gratings ringresonators Optical delay lines

mean-field and high temperature series expansion calculations of some magnetic properties of Ising and XY antiferromagnetic thin-films

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Chinese Physics B 2012年第8期21卷 487-493页

作者： r.Masrour M.hamedoun A.Benyoussef Laboratory of Materials ProcessesEnvironment and QualityCady Ayyed UniversityNational School of Applied SciencesSafiMorocco LMPhE(UrAC-12) Facult'e des SciencesUniversit'e Mohamed V-AgdalRabatMorocco Institute for Nanomaterials and Nanotechnologies MAScIrRabatMorocco Academie hassan II des Sciences et Techniques RabatMorocco

In this work, the magnetic properties of Ising and XY antiferromagnetic thin-films are investigated each as a function of Neel temperature and thickness for layers （n = 2, 3, 4, 5, 6, and bulk （∞） by means of a mean-field and high temperature series expansion （hTSE） combined with Pade approximant calculations. The scaling law of magnetic susceptibility and magnetization is used to determine the critical exponent γ, veff （mean）, ratio of the critical exponents γ/v, and magnetic properties of Ising and XY antiferromagnetic thin-films for different thickness layers n = 2, 3, 4, 5, 6, and bulk （∞）.

关键词： high-temperature series expansions mean-field theory antiferromagnetic thin film Pade approximant Neel temperature critical exponent