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Effect of Reactivity of Quick Lime on the Properties of hydrated Lime Sorbent for SO_2 Removal

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Journal of Materials Science & Technology 2009年第3期25卷 329-332页

作者： h.G. Shin h. Kim Y.N. Kim h.S. Lee Department of Materials Science and Engineering Seoul National University Material Analysis Team Korea Testing Laboratory School of Materials Science and Engineering Pusan National University

The hydration of quick lime and the sulfation of hydrated lime were carried out for verification of relationship between the reactivity of quick lime and the properties of hydrated lime as a sorbent. The effect of reactivity of quick lime was investigated with the change of calcination temperature and time. Results obtained showed that the temperature rise during the hydration of quick limes varied from 31 to 69℃ with the variation of calcination temperature and time. The specific surface area and the sulfation ability of hydrated lime prepared by hydration of quick lime showed a proportional relationship with the reactivity of quick lime. The hydrated lime which was prepared by hydration of quick lime calcined at 1100℃ had the highest reactivity and showed 41.53 m^2/g of the specific surface area, 0.16 cm^3/g of the pore volume and 87% of the removal efficiency for SO2 removal,

关键词： Reactivity Quick lime hydrated lime Calcination hydration Sorbent

Effects of oxide stringers on the β-phase depletion behaviour in thermally sprayed CoNiCrAlY coatings during isothermal oxidation

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Journal of Materials Science & Technology 2020年第10期42卷 108-116页

作者： h.Chen A.Rushworth Department of Mechanical Materials and Manufacturing EngineeringFaculty of Science and EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100China

This paper details an investigation of the effects of oxide stringers on theβ-phase depletion behaviour in thermally sprayed CoNiCrAlY *** Plasma Sprayed(VPS)Co NiCrAlY coatings,which are free of oxide stringers,are used as the reference materials in comparison with high-Velocity Oxy-Fuel(hVOF)sprayed CoNiCrAlY coatings during isothermal oxidation at 1100℃.An outer layer of spinel oxides and an inner layer of alumina are formed in the as-sprayed coatings,while only a single alumina scale is found in the heat-treated ***β-phase depletion occurred in the hVOF coatings than in the VPS *** was found that theβphases tend to coalesce at the oxide stringers in the hVOF coatings,which is likely due to the internal oxide particles and stringers acting as short diffusion barriers to tie up theβphase and inhibit theβ-phase depletion.

关键词： MCrAlY β-Phase depletion Oxidation Diffusion

Full-scale pullout tests of rock anchors in a limestone quarry focusing on bond failure at the anchor-grout and grout-rock interfaces

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2264-2279页

作者： Bjarte Grindheim Charlie CLi Are håvard høien Department of Geoscience and Petroleum Norwegian University of Science and Technology(NTNU)TrondheimNorway Norwegian Public Roads Administration(NPRA) BergenNorway

Rock anchors are a common safety measure for stabilising large-scale infrastructure,such as bridge towers,retaining walls,rock slopes and *** are four principal failure modes for rock anchors:(a)tensile failure of the steel anchor,(b)anchor-grout interface failure,(c)grout-rock interface failure,and(d)rock mass *** tests were performed in a limestone *** tests were designed to test failure modes B and C through *** the tests of failure mode B,the shear stress on the anchor-grout interface is the largest at the top of the grout column and attenuates towards the distal end for small *** shear stress becomes uniformly distributed when the applied load is approximately 50%of the ultimate pullout *** anchors designed to test failure mode C were installed with an endplate and had a higher toughness than the straight bar *** shear stress on the grout-rock interface is the largest at the endplate and attenuates upward before slip starts along the *** the ultimate pullout load is reached,and the grout column starts to slip,the shear stress is approximately *** bond shear strength on the anchor-grout interface was approximately 20%of the uniaxial compressive strength of the grout,and the bond strength of the grout-rock interface was around 5%for that of the *** grout-rock interface is likely determined by whichever is weaker,the grout or the rock.

关键词： Rock anchor Load transfer Shear stress distribution Bond shear strength Field test

Determination of Trace Amounts of Vanadium by Kinetic-Catalytic Spectrophotometric Methods

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Chinese Journal of Chemistry 2006年第4期24卷 557-562页

作者： POURETEDAL, h.R. KEShAVARZ, M.h. Department of Chemistry Malek-ashtar University of Technology Shahinshahr Iran

Kinetic-catalytic spectrophotometric methods were proposed for the determination of trace amounts of vanadium element as vanadium（Ⅳ） and/or V（Ⅴ） ions. The vanadium（Ⅳ） as VO^2＋ ion and/or vanadium（Ⅴ） as VO3^- ion showed a catalytic effect on the kinetic reactions between a color reagent such as methylthymol blue （MTB） or SPADNS and bromate in acidic media. The rate of decrease in the absorbance of the reagent MTB at 440 nm or SPADNS at 510 nm was proportional to concentration of V（Ⅳ） and/or V（Ⅴ） ions in the solution. The linear ranges for determination of vanadium were obtained in the range of 1.0-150 and 5.0-100.0 μg/L by the fixed-time and slope methods, respectively, with using MTB as reagent. In the presence of SPADNS as reagent, the calibration curves were made in the amplitude 1.0-200.0 and 5.0-150 μg/L of vanadium ion by the fixed-time and slope methods, respectively. Using fixed-time method, the limits of detection were obtained to be 0.5 and 0.7 μg/L of vanadium in the presence of MTB and SPADNS as reagents, respectively. Detection limits of vanadium by slope method and reagents of SPADNS and MTB were obtained to be 3.5 and 3.8 μg/L of vanadium, respectively. The proposed methods were applied successfully to determination of vanadium in synthetic and real samples.

关键词： kinetic-catalytic method SPADNS methylthymol blue vanadium

An Effective hybridization of Quantum-based Avian Navigation and Bonobo Optimizers to Solve Numerical and Mechanical Engineering Problems

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Journal of Bionic Engineering 2023年第3期20卷 1361-1385页

作者： Mohammad h.Nadimi-Shahraki Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad***Iran

hybrid metaheuristic algorithms play a prominent role in improving algorithms' searchability by combining each algorithm's advantages and minimizing any substantial shortcomings. The Quantum-based Avian Navigation Optimizer Algorithm (QANA) is a recent metaheuristic algorithm inspired by the navigation behavior of migratory birds. Different experimental results show that QANA is a competitive and applicable algorithm in different optimization fields. however, it suffers from shortcomings such as low solution quality and premature convergence when tackling some complex problems. Therefore, instead of proposing a new algorithm to solve these weaknesses, we use the advantages of the bonobo optimizer to improve global search capability and mitigate premature convergence of the original QANA. The effectiveness of the proposed hybrid Quantum-based Avian Navigation Optimizer Algorithm (hQANA) is assessed on 29 test functions of the CEC 2018 benchmark test suite with different dimensions, 30, 50, and 100. The results are then statistically investigated by the Friedman test and compared with the results of eight well-known optimization algorithms, including PSO, Kh, GWO, WOA, CSA, hOA, BO, and QANA. Ultimately, five constrained engineering optimization problems from the latest test suite, CEC 2020 are used to assess the applicability of hQANA to solve complex real-world engineering optimization problems. The experimental and statistical findings prove that the proposed hQANA algorithm is superior to the comparative algorithms.

关键词： Optimization Metaheuristic algorithms Evolutionary algorithm Quantum-based avian navigation optimizer algorithm Engineering optimization problems,Bionic algorithm

EXPERIMENTAL AND ThEORETICAL INVESTIGATION OF ThE FIRST FOLD CREATION IN ThIN WALLED COLUMNS

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Acta Mechanica Solida Sinica 2010年第4期23卷 353-360页

作者： Abbas Niknejad G.h.Liaghat h.Moslemi Naeini A.h.Behravesh Mechanical Engineering Department Yasouj University Faculty of Engineering Payame Noor University (PNU) Mechanical Engineering Department Faculty of EngineeringTarbiat Modares University

In this paper, a theoretical formula is presented to predict the instantaneous folding force of the first fold creation in square and rectangular columns under axial *** rectangular column is a small and single model of honeycombs with square or rectangular *** are based on the analysis of the Basic Folding Mechanism （BFM）.For this purpose, sum of the dissipated energy rate under bending around horizontal and inclined hinge lines and the dissipated energy rate under extensional deformations was equal to the work rate of the external force on the *** final formula obtained in this research, reasonably predicts the instantaneous folding force of single-cell square and rectangular honeycombs instead of the average ***, according to the calculated theoretical relation, the instantaneous folding force of the first fold creation in a square column was sketched versus folding distance and compared to the experimental results, which showed a good correlation.

关键词： dissipated energy rate first fold creation instantaneous folding force thin walled column

An Initial Analysis of a Strongly Lensed QSO Candidate Identified by LAMOST

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Research in Astronomy and Astrophysics 2023年第10期23卷 349-356页

作者： Y.h.Chen M.Y.Tang h.Shu h.Tu Institute of Astrophysics Chuxiong Normal UniversityChuxiong 675000China School of Physics and Electronical Science Chuxiong Normal UniversityChuxiong 675000China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming 650091China Physics Department&Shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China

From 2011 to 2021,LAMOST has released a total of 76,167 quasar *** try to search for gravitationally lensed QSOs by limiting coordinate differences and redshift differences of these *** name,brightness,spectrum,photometry and other information of each QSO will be visually checked *** attention should be paid to check whether there are groups of galaxies,gravitationally lensed arcs,Einstein crosses,or Einstein rings near the *** careful selection,we select LAMOST J160603.01+290050.8(A)and LAMOST J160602.81+290048.7(B)as a candidate and perform an initial *** A and B are336 apart and they display blue during photometric *** redshift values of components A and B are0.2%different,their Gaia_g values are 1.3%different,and their ugriz values are 1.0%or less *** the spectra covering from 3690 to 9100?,the emission lines of C II,Mg,hγ,OⅢ,and hβare present for both components A and B and the ratio of flux(B)to flux(A)from LAMOST is basically a constant,around ***,no galaxies have been found between components A and *** et *** them as binary *** we accidentally find a galaxy group near components A and *** the center of dark matter in the galaxy group is at the center between components A and B,components A and B are probably gravitationally lensed *** estimate that the Einstein mass is 1.46×10^(11)M_⊙and the total mass of the lens is1.34×10^(13)M_⊙.The deflection angle is 197 at positions A and B and the velocity dispersion is 261 km s^(-1).Theoretically,this candidate could be a pair of fold images of a strong lensing system by a galaxy group,and we will investigate the possibility when the redshifts of nearby galaxies are available.

关键词： gravitational lensing:strong (galaxies:)quasars:individual(LAMOST J1606+2900) techniques:imaging spectroscopy

Effects of Austempering and Martempering Processes on Amount of Retained Austenite in Cr-Mo Steels (FMU-226) Used in Mill Liner

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Journal of Iron and Steel Research International 2010年第2期17卷 53-58页

作者： M h Shaeri h Saghafian S G Shabestari School of Metallurgy and Materials Engineering Iran University of Science and Technology

The presence of retained austenite gives rise to deterioration of the wear resistance and fracture strength of Cr-Mo steels in many cases. Thus, the effects of heat treatments including direct quenching, martempering, and austempering on the retained austenite existing in the microstrueture of these steels were investigated. Specimens were austenized at 950 ℃ followed by direct quenching using compressed and still air. The specimens were also isothermally quenched in salt bath at 200 and 300 ℃ for 2, 8, 30, and 120min. Microstructures of the specimens were studied using optical microscope （traditional black and white etching as well as color etching）, scanning electron microscope （SEM）, microhardness tester, and X-ray diffraction （XRD）. The results showed that the lowest amount of retained austenite in the microstructure was obtained in the specimens quenched isothermally at 300 ℃ for 120 min.

关键词： Cr-Mo steel austempering martempering retained austenite microstructure

EXPLORATION　ON　ThE　BASIC　ACTIVE　CENTRES　OF　KF/Al_2O_3:EFFECTOF　PRETREATMENT　TEMPERATURE

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Chinese Chemical Letters 1995年第9期6卷 811-814页

作者： Zhu, Jh Tsuji, h Kabashima, h hattori, h Kita, h Nanjing Univ Dept Chem Nanjing 210093 Peoples R China hokkaido Univ Grad Sch Environm Earth Sci Div Sci Mat Sapporo Hokkaido 060 Japan hokkaido Univ Ctr Adv Res Energy Technol Sapporo Hokkaido 060 Japan

Abstract: KF/Al2O3 reached maxinmun activity at the pretreatment temperature(Tp) of 623K or 723K in Ibuters isomerization at 273K. according to the amount of KF loaded. Further increment of Tp lowered the activity of KF/Al2O3 due the suppression of [Al-OhF]strong basic sites through dehydroxylation. Changes in the state and function ofF caused the deactivation of KF/Al2O3 at high Tp.

关键词： KF/Al2O3 PRETREATMENT ThE CENTRES BASIC ACTIVE Al