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Effect of CeO_2 on heat transfer and crystallization behavior of rare earth alloy steel mold fluxes

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 565-572页

作者： ze-yun Cai Bo Song Long-fei Li Zhen Liu Xiao-kang cui School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

To improve the heat transfer capability and the crystallization property of the traditional mold flux, CaF_2 was replaced with B_2O_3. Then, the influences of CeO_2 on the heat transfer and the crystallization of the CaF_2-bearing mold flux and the new mold flux with 10 wt% B_2O_3 were studied using a slag film heat flux simulator and X-ray diffraction(XRD). The results revealed that the addition of CeO2 reduced the heat transfer by increasing the solid slag thickness and the crystallization of two mold fluxes. However, CeO_2 had less effect on the B_2O_3-containing mold flux compared with the CaF_2-bearing mold flux. According to the analyses, the CeO_2 contents in the CaF_2-bearing mold flux and the B_2O_3-containing mold flux should not exceed 8 wt% and 12 wt%, respectively. Therefore, these experimental results are beneficial to improve and develop the mold flux for casting rare earth alloy steels.

关键词： cerium oxide boron trioxide mold fluxes heat transfer crystallization rare earth alloy steels

Octanuclear Palladacycles with B(3)-H Bond Activation of o-Carborane

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Chinese Journal of Chemistry 2023年第3期41卷 307-313页

作者： Run-ze Yuan Peng-Fei cui Yue-Jian Lin Guo-Xin Jin State Key Laboratory of Molecular Engineering of Polymers Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsDepartment of ChemistryFudan University2005 Songhu RoadShanghai200433 China

Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane *** substitution reaction of 1 has been explored,and three of its substituted complexes Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(L)4(L=^(t)BuNC,2;L=C_(5)H_(5)N,3;L=C_(4)H_(8)S,4)have been *** m-and p-carborane disubstituted ligands m-and p-C_(2)B_(10)H_(10)(CS_(2)CH_(3))_(2)(ligands 5 and 6)as well as their B—H activated carborane complexes[m-C_(2)B_(10)H_(9)(CS_(2)CH_(3))_(2)PdCl](7)and[p-C_(2)B_(10)H_(8)(CS_(2)CH_(3))_(2)][PdCl(^(t)BuNC)]_(2)(8)have also been synthesized by the similar *** of these complexes have been characterized,including X-ray single crystal diffraction,NMR spectroscopy,IR spectroscopy and elemental analysis methods.

关键词： Carborane Palladacycle Regioselective B-H activation Polynuclear complex Dithioester chemistry

Phase stability of Fe_(23)Zr_(6)and thermodynamic reassessment of Fe-Zr system

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Journal of Iron and Steel Research International 2021年第11期28卷 1375-1389页

作者： ze-ting Du Lei Zou cui-ping Guo Xue-ping Ren Chang-rong Li Department of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Northwest Institute for Nonferrous Metal Research Xi’an 710016ShaanxiChina

The stability of the Fe_(23)Zr_(6)phase in Fe–Zr system was studied,and the partial Fe–Zr phase diagram was revised by means of X-ray diffraction,electron probe microanalysis and differential thermal analysis *** the basis of the experimental results in the present work and literature,the Fe–Zr system was reassessed using CALculation of PHAse Diagram(CALPHAD)*** phases,liquid,fcc,bcc and hcp,are modeled as the substitutional *** intermetallic compounds,hex.-Fe_(2)Zr,Fe_(2)Zr,FeZr_(2)and FeZr3 phases,are treated as Fe_(2)(Fe,Zr)1,(Fe,Zr)2(Fe,Zr)1,(Fe,Zr)1Zr_(2)and(Fe,Zr)1(Fe,Zr)3 by a two-sublattice model,*** Fe_(23)Zr_(6)phase is treated as stoichiometric compound.A set of self-consistent thermodynamic parameters of the Fe–Zr system was *** results confirm the stability of Fe_(23)Zr_(6)phase,improve the phase diagram of the Fe–Zr system and provide a theoretical reference for the development of Zr alloys.

关键词： Fe_(23)Zr_(6) Fe–Zr system Thermodynamic parameter CALPHAD method

Effect of Al2O3 on the viscosity of CaO-SiO2-Al2O3-MgO-Cr2O3 slags

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International Journal of Minerals,Metallurgy and Materials 2021年第5期28卷 797-803页

作者： Chen-yang Xu cui Wang Ren-ze Xu Jian-liang Zhang Ke-xin Jiao School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

We investigated the effect of Al2O3 content on the viscosity of CaO-SiO2-Al2O3-8wt%MgO-1wt%Cr2O3(mass ratio of CaO/SiO2 is 1.0,and Al2O3 content is 17wt%-29wt%)*** results show that the viscosity of the slag increases gradually with increases in the Al2O3 content in the range of 17wt%to 29wt%due to the role of Al2O3 as a network former in the polymerization of the aluminosilicate structure of the *** increases in the Al2O3 content from 17wt%to 29wt%,the apparent activation energy of the slags also increases from 180.85 to 210.23 kJ/mol,which is consistent with the variation in the critical *** Fourier-transform infrared spectra indicate that the degree of polymerization of this slag is increased by the addition of *** application of Iida’s model for predicting the slag viscosity in the presence of Cr2O3 indicates that the calculated viscosity values fit well with the measured values when both the temperature and Al2O3 content are at relatively low levels,i.e.,the temperature range of 1673 to 1803 K and the Al2O3 content range of 17wt%-29wt%in CaO-SiO2-Al2O3-8wt%MgO-1wt%Cr2O3 slag.

关键词： slag viscosity high aluminium oxide apparent activation energy structure viscosity prediction

APPLICATION OF TREFFTZ BEM TO ANTI-PLANE PIEZOELECTRIC PROBLEM

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Acta Mechanica Solida Sinica 2006年第4期19卷 352-364页

作者： Wang Juan cui Yuhong qin qinghua Jia Jiangying Department of Mechanics Tianjin University Tianjin 30072 China Department of Engineering Australian National University Canberra ACT 0200 Australia

Anti-plane electroelastic problems are studied by the Trefftz boundary element method （BEM） in this paper. The Trefftz BEM is based on a weighted residual formulation and indirect boundary approach. In particular the point-collocation and Galerkin techniques, in which the basic unknowns are the retained expansion coefficients in the system of complete equations, are considered. Furthermore, special Trefftz functions and auxiliary functions which satisfy exactly the specified boundary conditions along the slit boundaries are also used to derive a special purpose element with local defects. The path-independent integral is evaluated at the tip of a crack to determine the energy release rate for a mode Ⅲ fracture problem. In final, the accuracy and efficiency of the Trefftz boundary element method are illustrated by an example and the comparison is made with other methods.

关键词： Trefftz boundary element, point-collocation technique, Galerkin technique, special trial function anti-plane fracture, piezoelectric medium

A dual-band wireless communication of spoof plasmonic meta-waveguide

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Science China(Information Sciences) 2024年第7期67卷 337-338页

作者： Xinxin GAO Geng-Bo WU ze GU Qian MA Wenyi cui Tiejun cui Chihou CHAN State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong State Key Laboratory of Millimeter Waves Southeast University Department of Electrical Engineering City University of Hong Kong

The ever-growing demands in wireless communications,computational imaging, and light detection necessitate the capability to freely manipulate electromagnetic *** and highly integrated devices hold great promise for the future of communications. Spoof plasmonic metamaterials, in particular, have shown potential in creating functional devices and systems due to their ultracompact and low-profile advantages [1–3].

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Timming of Lithospheric Extension in Northeastern China:Evidence from the Late Mesozoic Nianzishan A-Type Granitoid Complex

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Journal of Earth Science 2019年第4期30卷 689-706页

作者： Jinhua qin cui Liu Yuchuan Chen Jinfu Deng MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China

New zircon U-Pb dates obtained by laser ablation inductively coupled plasma mass spectrometry（LA-ICP-MS）,whole-rock geochemical data and Sm-Nd and Rb-Sr isotopic data are presented for miarolitic alkaline granites,porphyritic syenite and rhyolites of the Nianzishan A-type granitoid complex（NAGC）in the Great Xing’an Range-Songliao Basin in Northeast（NE）*** crystallization ages of 112.95±0.93 and 114.1±1.71 Ma for granite and 118.6±0.51 Ma for porphyritic syenite were determined by high-precision *** εNd（t）of the rocks range from +1.85 to+2.06,with Nd model ages(TDM1)from 671 to 821 Ma,indicating that the NAGC originated from juvenile source rocks and exhibits geochemical characteristics of A1-and AA-type granite which formed in an extensional *** attribute the magmatism to regional extension and lithospheric thinning caused by the subduction of the western Pacific Plate about 120 to 100 Ma.

关键词： AA-type granitee new zircon UU-Pb zircon agees NE China lithospheric exxtension

Critical environmental factors affecting mountain geohazards in a warming climate in Southwest China

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Advances in Climate Change Research 2024年第4期15卷 695-707页

作者： Xiao-Ming XU Peng cui Xue-qin ZHANG Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 10010lChina University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Environmental factors are essential input variables for susceptibility assessment models of mountain ***,the existing literature provides a limited understanding of the relative contribution of these factors to the occurrence of geohazards with a warming climate,posing tremendous challenges for risk management in mountainous ***'an city is susceptible to hazards because of its steep terrain,abundant precipitation and active seismic *** this regard,we utilise the GeoDetector model to extract critical environmental factors affecting the spatial patterns of mountain geohazards(i.e.,landslide,debris flow and rockfall)in Southwest *** analysis indicates that the factors with the highest explanatory power for the spatial distribution of landslides,debris flows,and rockfalls are soil property,extreme precipitation and extreme temperature,***,we revealed the synergistic effects among factors given their larger q-value than individual *** further explored the responses of mountain geohazards to climate change,including the rising temperature and precipitation,because the frequent occurrence of mountain geohazards is closely related to a warming *** variation in snow water equivalent caused by antecedent snowfall and snowdrifts acts as a crucial indicator for geohazards,highlighting the significance of snow and wind observations in meteorological nowcasting and disaster *** disclose the phenomenon of the geohazard hysteresis to the precipitation peak resulting from the top-down(i.e.,precipitation-runoff and surface-deep soil moisture)peak *** work is expected to enhance the precision of susceptibility assessment models and the reliability of short-term forecasts for mountain geohazards.

关键词： Mountain geohazards Environmental factors Climate change GeoDetector Southwest China

f and g series solutions to a post-Newtonian two-body problem with parameters β and γ

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Research in Astronomy and Astrophysics 2016年第1期16卷 135-144页

作者： Song-He qin Jing-Xi Liu ze-Hao Zhong Yi Xie School of Astronomy and Space Science Nanjing University Nanjing 210093 China Shanghai Key Laboratory of Space Navigation and Position Techniques Shanghai 200030 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education Nanjing 210093 China

Classical Newtonian f and g series for a Keplerian two-body problem are extended for the case of a post-Newtonian two-body problem with parameters β and γ. These two parameters are introduced to parameterize the post-Newtonian approximation of alternative theories of gravity and they are both equal to1 in general relativity. Up to the order of 30, we obtain all of the coefficients of the series in their exact forms without any cutoff for significant figures. The f and g series for the post-Newtonian two-body problem are also compared with a Runge-Kutta order 7 integrator. Although the f and g series have no superiority in terms of accuracy or efficiency at the order of 7, the discrepancy in the performances of these two methods is not quite distinct. However, the f and g series have the advantage of flexibility for going to higher *** examples of relativistic advance of periastron are given and the effect of gravitational radiation on the scheme of f and g series is evaluated.

关键词： gravitation - celestial mechanics - binaries: general