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Solubility of Ba in Liquid Iron and Interaction Effect of the Third Elements

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International Journal of Minerals,metallurgy and Materials 2000年第2期14卷 82-85页

作者： Bo Song Qiyong Han Chenming zhang(metallurgy {2., university of science and technology Beijing, Beijing 100083, china) metallurgy school University of Science and Technology Beijing Beijing 100083 China

Experiments were carried out at 1873 K in a double-temperature zone furnace using vapor pressure method. The equilibriumtests of bedum vapor with liquid iron were conducted in CaO crucibles sealed in a Mo chamber. As a result, the experiments obtainedthe relation between the dissolved content of Ba in liquid iron and the vapor pressure of Ba and the standard Gibbs energies for the re-actions Ba(g)=[Ba] and Ba(l)=[Ba].

关键词： Ba dissolution equilibrium liquid iron interaction parameter

Sol-gel Preparation Copper-cadmium Halide DopedPhotochromic Glass Coating on Plate Glass

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International Journal of Minerals,metallurgy and Materials 2000年第1期14卷 34-37页

作者： ShiyongLuo Jiayun zhang Jixiang Liu metallurgy {2., university of science and technology Beijing, Beijing 100083, china Wuhan university of technology, Wuhan 430070, china Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China Wuhan Univ Technol Wuhan 430070 Peoples R China

Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR) spectrum investigations indicate that the photochromic phase of tile coating is CuBr_xCl_(1-x), solid solution, and that the structure network of the coating is connected with the bonds of Si-O-Si, Si-O-B and Si-O-Al.

关键词： photochromic glass coating sol-gel photochromic phase, structure network

Recent progress in carbene-catalyzed fluoroalkylation

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science china Chemistry 2024年第8期67卷 2448-2460页

作者： Bei zhang Xuan zhang {2. Wang jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China school of Pharmaceutical sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

Nanophononic metamaterials induced proximity effect in heat flux regulation

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Frontiers of physics 2024年第2期19卷 149-156页

作者： jian zhang Haochun zhang Gang zhang school of Energy science and Engineering Harbin Institute of TechnologyHarbin 150001China Institute of High Performance Computing Agency for ScienceTechnology and Research(A*STAR)Singapore 138632Singapore

Recent studies have shown that the construction of nanophononic metamaterials can reduce thermal conductivity without affecting electrical properties,making them promising in many fields of application,such as energy conversion and thermal ***,although extensive studies have been carried out on thermal conductivity reduction in nanophononic metamaterials,the local heat flux characteristic is still *** this work,we construct a heat flux regulator which includes a silicon nanofilm with silicon *** regulator has remarkable heat flux regulation ability,and various impacts on the regulation ability are ***,even in the region without nanopillars,the local heat current is still lower than that in pristine silicon nanofilms,reduced by the neighboring nanopillars through the thermal proximity *** combine the analysis of the phonon participation ratio with the intensity of localized phonon modes to provide a clear *** findings not only provide insights into the mechanisms of heat flux regulation by nanophononic metamaterials,but also will open up new research directions to control local heat flux for a broad range of applications,including heat management,thermoelectric energy conversion,thermal cloak,and thermal concentrator.

关键词： nanophononic metamaterials proximity effect

Pulsation Treatment on the Modification of Crystal with Cold Simulation

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International Journal of Minerals,metallurgy and Materials 1999年第1期13卷 20-23页

作者： jianzhong Wang Yong Tang Daqiang Cang Jiaquan zhang({2. school, university of science and technology Beijing, Beijing 100083, china) metallurgy school University of Science and Technology Beijing Beijing 100083 China

Since the separation of crystal of KCl saturated aqueous is similar to the crystallization of liquid metals, the melts nucleation can be simulated by the experiment of the crystal of salt aqueous solution. In this experiment pulsation treatment was imposed on KCl saturated aqueous in order to study the effect of pulsation treatment on crystallization in the salt solution, and the influence of different pulsation treating time, super-heating and bine of prescription were investigated. The results show that it is possible to modify the crystallization over satured solution temperature and the degree of under-cooling for salt crystal separation was reduced by applying pulse treating on KCl saturated aqueous solution. In addition, this technology may generate embryos for nucleation even at the temperature over melting point or satured solubility.

关键词： saturated aqueous solution pulse modification treatment nucleation, crystal

CALCULATING MODELS OF MASS ACTION CONCENTRATIONSFOR MATTES (Cu_2.-FeS-SnS)INVOLVING EUTECTIC

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Acta Metallurgica Sinica(English Letters) 1997年第5期10卷 392-397页

作者： J. zhang (Department of metallurgy, {2. of science and technology Beijing, Beijing 100083, china) Univ of science and technology Beijing Beijing China

Based on the facts that cations and anions of molten salts and binary basic oxide solid solutions do not separate from each other as well as that the electric conductivities of mattes are greater than that of salts and basic oxide solid solutions, the calculating models of mass action concentrations for binary and ternary mattes involving eutectic have been formulated. The results of calculation agree well with the values measured;this in turn shows that the calculating models can reftect the structural characteristics of the mattes concerned.

关键词： matte activity eutectic mass action concentration

Algorithm for Computation of Unstructured Real Stability Radius and Its Applications

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International Journal of Minerals,metallurgy and Materials 1998年第4期12卷 245-250页

作者： Xiaodan zhang Lequan Min(Applied science {2., university of science and technology Beijing, Beijing 100083, china) Applied science school University of Science and Technology Beijing Beijing 100083 China

An algorithm for the computation of the unstructured real stability radius of high dimensional linearsystem is presented. Using the accurate formula of the real stability radius of 2.dimensional system linear systemchecks the algorithm. The result shows that the algorithm is reliable and efficient. As applications, the unstructuredreal stability radii of 2.dimensional Chua's circuit and 3-dimensional piecewise-linear system are calculated, thedynamical orbits of the corresponding perturbed systems are simulated.

关键词： lincar systems stability robustness parameter perturbation computational methods

Nonclassical Plane-crystallographic Groups and Their Applications IV

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International Journal of Minerals,metallurgy and Materials 1998年第4期12卷 228-232页

作者： Lequan Min Xaodan zhang(Applied science {2., {2.,university of science and technology Beijing, Beijing 100083,china) Applied science school University of Science and Technology Beijing Beijing 100083 China

Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are *** can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted bythe projections on the plane of the corresponding unit cells consisting of embedding polyhedrons, respectively. TheFourier-transform patterns of the Periodic lattices have striking approximate'8-fold rotational symmetries', some ofwhich are similar to those displaying in the electrton-diffraction patterns of so-called quasicrystals.

关键词： nonclasslcal crystallographic groups locoally 8-fold symmetry Fourier-transform patterns, quasicrystals

Effects of Temperature and [S] on the Kinetics of Nitrogen Removal from Liquid Steel

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Journal of Materials science & technology 2001年第2期17卷 233-236页

作者： Jie FU, Shixiang ZHOU, Ping WANG, Lin DI and jian ZHU metallurgy {2., university of science and technology Beijing, Beijing 100083, china Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China

The kinetics of denitrogenation from liquid steel was studied by using an oxygen-nitrogen analysis system(LECO TC-436) under 1600 degreesC similar to 2.13 degreesC conditions. The results show that when [S]=0.005%, nitrogen removal was controlled by nitrogen transfer in liquid diffusion layer, when [S]=0.012. and 0.140%, it was controlled by both nitrogen transfer in liquid diffusion layer and the chemical reaction at the liquid-gas interface below 2.50 degreesC, and by nitrogen transfer in liquid diffusion layer under 2.50 degreesC similar to 2.13 degreesC conditions. The activation energy E-a was 57 kJ/mol for 0.0050%[S], 95 kJ/mol for 0.012.[S], 165 kJ/mol for 0.140%[S]. The resistance of sulphur on nitrogen removal decreased with the temperature rose, and disappeared at 2.30 degreesC. Based on the results obtained, it has been answered why the nitrogen in liquid steel can be decreased rapidly by carbon-oxygen reaction under very high oxygen and sulphur content conditions during the BOF, EAF, VOD and AOD steelmaking processes.

关键词： Effects of Temperature and on the Kinetics of Nitrogen Removal from Liquid Steel