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Artificial neural network approach for rheological characteristics of coal-water slurry using microwave pre-treatment

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International Journal of Mining science and Technology 2017年第2期27卷 379-386页

作者： b.K.sahoo s.De b.C.Meikap Department of Chemical Engineering Indian Institute of Technology Research and Development Centre for Iron and steel Steel Authority of India Limited Chemical Engineering School of Engineering Howard College University of Kwazulu-Natal

Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheology characteristic for microwave pre-treatment of coal-water slurry(CWs) was performed in an online bohlin viscometer. The non-Newtonian character of the slurry follows the rheological model of Ostwald de Waele. The values of n and k vary from 0.31 to 0.64 and 0.19 to 0.81 Pa·sn,respectively. This paper presents an artificial neural network(ANN) model to predict the effects of operational parameters on apparent viscosity of CWs. A 4-2-1 topology with Levenberg-Marquardt training algorithm(trainlm) was selected as the controlled ANN. Mean squared error(MsE) of 0.002 and coefficient of multiple determinations(R^2) of 0.99 were obtained for the outperforming model. The promising values of correlation coefficient further confirm the robustness and satisfactory performance of the proposed ANN model.

关键词： Microwave pre-treatment Coal-water slurry Apparent viscosity Artificial neural network back propagation algorithm

Revisiting Laser-Intensity-Dependent Ionization and Fragmentation of C60

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Chinese Physics Letters 2021年第8期38卷 32-37页

作者： D.P.Dong b.H.yang D.b.Qian W.C.Zhou s.F.Zhang X.Ma Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of sciences Beijing 100049China

We revisit the laser-intensity-dependent ionization and fragmentation yields of C60 molecules irradiated by 25-fs,798-nm laser pulses based on the approach in which photoions are measured via a velocity map imaging spectrometer working in a time-sliced *** approach dramatically improves the signal-to-background ratio compared to those using a simple(traditional)time-of-flight mode(spectrometer),and thus allows us to measure the laser-intensity dependences down to a previously untouched region,which is expected to provide new insights into the intense-field ionization and fragmentation of ***,we find that the saturation intensities for C60 ionizations and the onset intensity for C60 fragmentation are much lower than those reported in previous ***,the derived saturation-intensity dependence on charge distribution demonstrates the validity of the over-the-barrier ionization using a conducting sphere model.

关键词： fragmentation saturation ionization

An optimized ion trap geometry to measure quadrupole shifts of ^(171)Yb~＋ clocks

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Chinese Physics b 2016年第11期25卷 230-237页

作者： N batra b K sahoo s De Academy of scientific and Innovative Research CSIR-NPL Campus New Delhi India CsIR-National Physical Laboratory Dr. K. S. Krishnan Marg New Delhi 110012 India Theoretical Physics Division Physical Research Laboratory Navrangpura Ahmedabad 380009 India

We propose a new ion-trap geometry to carry out accurate measurements of the quadrupole shifts in the （171）Yb *** trap will minimize the quadrupole shift due to the harmonic component of the confining potential by an order of *** will be useful to reduce the uncertainties in the clock frequency measurements of the 6s 2s（1/2）→4f（13）6s2 2F（7/2）and 6s 2s（1/2）→5d2D（3/2） transitions,from which we can deduce the precise values of the quadrupole moments（0s） of the 4f（13）6s2 2F（7/2） and 5d2D（3/2） ***,it may be able to affirm the validity of the measured 0 value of the4f（13）6s22F（7/2） state,for which three independent theoretical studies defer almost by one order of magnitude from the *** also calculate 0s using the relativistic coupled-cluster（RCC） *** use these 0 values to estimate the quadrupole shift that can be measured in our proposed ion trap experiment.

关键词： validity minimize carry clock relativistic precise deduce magnitude expectation spatially

Analysis of Mechanical Properties of Injection Molded short Glass Fibre (sGF)/Calcite/Abs Composites

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Journal of Materials science & Technology 1997年第5期13卷 389-396页

作者： Fu, s.Y. Lauke, b. Institute for Polymer Research Dresden e.V 01069 Dresden Hohe Str.6 Germany

Acrylonitrile-butadiene-styrene (Abs), with and without calcium carbonate (calcite) particles,was used as the matrix for reinforcement with as-received short-glass fibres (were originallytreated by the manufacturer) and sized short-glass fibres with two amino-silane coupling *** calcite particle content is 0, 11.7 and 23.5 vol. pct for the matrices. The glass fiber contentis 0, 10 and 15 vol. pct. The matrix materials and corresponding composites were compoundedusing a twin screw extruder and dumbbell-shaped tensile bars were prepared with an injectionmolding process. The tensile and flexural properties as well as the unnotched and notchedCharpy impact energies of short glass fibre/calcite/Abs composites were studied in this *** effects of fibres, fibre surface treatments and particles on these mechanical properties ofthe composites were discussed in detail. An importarit information was obtained, which is thatthe tensile and flexural strengths of hybrid sGF/calcite/Abs composites are the same as thoseof corresponding fibre composites when the ratio of the interfacial adhesion strength betweenparticles and matrix to that between fibres and matrix is higher than certain value. otherwise theformer are lower than the latter.

关键词： Abs Calcite/Abs Composites sGF Analysis of Mechanical Properties of Injection Molded short Glass Fibre

Constraining the Temperature-density Relation of the Inter-galactic Medium from Analytically Modeling LyαForest Absorbers

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Research in Astronomy and Astrophysics 2023年第4期23卷 72-84页

作者： Li yang Zheng Zheng T.-s.Kim shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China school of Astronomy and space sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics and Astronomy University of Utah115 S 1400 ESalt Lake CityUT 84112USA Department of Astronomy University of Wisconsin475 North Charter StreetMadisonWI 53706USA

The absorption by neutral hydrogen in the intergalactic medium(IGM)produces the Lya forest in the spectra of *** Lya forest absorbers have a broad distribution of neutral hydrogen column density N_(HⅠ) and Doppler b *** narrowest Lya absorption lines(of lowest b)with neutral hydrogen column density above~10^(13)cm^(-2) are dominated by thermal broadening,which can be used to constrain the thermal state of the *** we constrain the temperature-density relation T=T0(ρ/■)γ^(-1) of the IGM at 1.6by using N_(HⅠ) and b parameters measured from 24 high-resolution and high-signal-to-noise quasar spectra and by employing an analytic model to model the N_(HⅠ) -dependent low-b cutoff in the b *** each N_(HⅠ) bin,the b cutoff is estimated using two methods,one non-parametric method from computing the cumulative b distribution and a parametric method from fitting the full b *** find that the IGM temperature T0 at the mean gas densityρshows a peak of~1.5×10^(4) K at z~*** redshift higher than this,the indexγapproximately remains constant,and it starts to increase toward lower *** evolution in both parameters is in good agreement with constraints from completely different approaches,which signals that HeⅡreionization completes around z~3.

关键词： (galaxies:)intergalactic medium-(galaxies:)quasars absorption lines-radiation mechanisms thermal

Microstructure,texture and mechanical behavior characterization of hot forged cast ZK60 magnesium alloy

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Journal of Materials science & Technology 2017年第9期33卷 907-918页

作者： s.M.H.Karparvarfard s.K.shaha s.b.behravesh H.Jahed b.W.Williams Department of Mechanical & Mechatronics Engineering University of Waterloo Canmet MATERIALs Natural Resources Canada

structure with a significant reduction in casting porosity, while the texture changed to sharp basaMeasured mechanical properties of the forged alloy showed that strength did not change, howductility improved by 75%. The analysis of the fracture surface of the forged alloy under tension rea ductile fracture with dimple morphology, while the as-cast alloy displayed a brittle fracture with pores. This demonstrated that the reduction of casting defects and dendritic morphology, as well evolution of recrystallized grains, enhanced ductility, while partial dynamic recrystallization throuforging process resulted in only marginal modification of strength in the forged condition.. 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials sciTechno

关键词： Magnesium Forging Ductility Texture Recrystallization

Injection of N-Radicals into Diesel Engine Exhaust Treated by Plasma for Improved NO_x Removal: A Feasibility study

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Plasma science and Technology 2006年第2期8卷 202-206页

作者： b. s. RAJANIKANTH b. R. sUsHMA Dept. of High Voltage Engineering Indian Institute of Science Bangalore 560012 India

Reported in this paper is a feasibility study on the injection of plasma induced N radicals for the abatement of NO and NOx present in the actual diesel exhaust. The radical laden diesel exhaust was further treated by discharge plasma in a dielectric barrier discharge reactor. N radicals were produced in a separate plasma reactor filled with baTiO3 pellets and were then injected into the treatment zone, There was a significant improvement in the efficiency when the radicals were injected compared to that when there was no radical injection. The efficiency of NOx removal at 0 load with plasma alone was 14% whereas with the injection of N radicals it went up to 38%, The results of the experiments conducted at different loads are discussed,

关键词： N-radical diesel engine exhaust NOx removal plasma treatment

Temperature Effect on Early Oxidation behavior of NiCoCrAlY Coatings: Microstructure and Phase Transformation

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Acta Metallurgica sinica(English Letters) 2022年第6期35卷 975-984页

作者： A.Ullah A.Khan Z.b.bao Y.F.yang M.M.Xu s.L.Zhu F.H.Wang University of Chinese Academy of sciences Beijing 100049China shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Green Fabrication and surface Technology of Advanced Metal Materials Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243000China Institute of Advanced Wear and Corrosion Resistant and Functional Material Jinan UniversityGuangzhou 510632China shenyang National Laboratory for Materials science Northeastern UniversityShenyang 110819China

Initial oxidation behavior of NiCoCrAlY coating prepared by arc-ion plating has been studied in air at 900, 1000 and 1100 ℃. The results showed that phase transformation from transient θ-Al_(2)O_(3) to α-Al_(2)O_(3) was highly related to the temperature and oxidation time. The oxide scale in the initial stage was mainly composed of θ-Al_(2)O_(3) at 900 ℃. Instead, more amount of α-Al_(2)O_(3) emerged out with increasing oxidation temperature. The elemental distribution after oxidation confirmed that faster chromium diffusion to the oxide scale played an important role in the speedy transformation from θ-Al_(2)O_(3) to α-Al_(2)O_(3). Y segregation at scale/coating interface resulted in less cavity formation and hence improved the oxide scale adherence.

关键词： MCrAlY coating Phase transformation Isothermal oxidation Temperature effect

Degradation of synthetic Dyeing Wastewater by Underwater Electrical Discharge Processes

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Plasma science and Technology 2013年第7期15卷 659-665页

作者： s.D.KIM D.I.JANG b.J.LIM s.b.LEE Y.s.MOK Yeongsan River Environment Research Center National Institute of Environmental ResearchGwangju 500-480 Korea Department of Chemical and biological Engineering Jeju National UniversityJeju 690-756 Korea

Electrical discharge treatments of synthetic dyeing wastewater were carried out with two different systems： underwater pulsed electrical discharge （UPED） and underwater dielectric barrier discharge （UDbD）. Reactive blue 4 （Rb4） and Acid Red 4 （AR4） were used as model contaminants for the synthetic wastewater. The performance of the aforementioned systems was compared with respect to the chromaticity removal and the energy requirement. The results showed that the present electrical discharge systems were very effective for degradation of the dyes. The dependences of the dye degradation rate on treatment time, initial dye concentration, electrical energy, and the type of working gas including air, 02, and N2 were examined. The change in the initial dye concentration did not largely affect the degradation of either Rb4 or AR4. The energy delivered to the UPED system was only partially utilized for generating reactive species capable of degrading the dyes, leading to higher energy requirement than the UDbD system. Among the working gases, the best performance was observed with O2. As the degradation proceeded, the concentration of total dissolved solids and the solution conductivity kept increasing while pH showed a decreasing trend, revealing that the dyes were effectively mineralized.

关键词： degradation dyeing wastewater pulsed electrical discharge dielectric barrierdischarge