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Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of Materials science & technology 2010年第5期26卷 445-448页

作者： Shuming Wang and Fenghua Kuang school of Materials science and Engineering,{2. of science & technology beijing,beijing 100083.china school of Materials science and Engineering University of Science & Technology Beijing Beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2.l4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2.3.doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3. for Al3. in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3. substitution Solid solution

Annealing Texture Evolution of Ti-IF Steel during Batch Annealing

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 175-179页

作者： Jing Shi Xianjin Wang(Material science and Engineering school,{2.,{3.) Material science and Engineering school University of Science and Technology Beijing Beijing 100083 China

Texture development and recrystallization behavior of Ti-IF steel during Batch Annealing (BA) were investigared with X-ray diffraction and EBSP in lab, and the results were compared with research work on continu ous annealing (CA) with rapid heating rate. The basic tendencies are similar that eary nucleation takes place in ND fibers, RD fibers are consumed at the end of recrystallization, and ND texture dominates over annealing texture. However, the detailed texture transformation during batch annealing is different and somewhat more compicated than tha in rapid-heating process. Moreover, misorientation plays an important role in texture transformation of BA In addition, the results of EBSP are consistent with that of ODF well.

关键词： Ti-IF steel texture batch annealing X-ray diffraction EBSP

A New Genetic Algorithm Based on Niche Technique and Local Search Method

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Journal of university of science and technology beijing 2001年第1期8卷 63-68页

作者： Jinwu Xu, Jiwen Liu Mechanical Engineering school, university of science and technology beijing,{2. Mechanical Engineering school Univ. of Sci. and Technology Beijing Beijing 100083 China

The genetic algorithm has been widely used in many fields as an easy robust global search and optimization method. In this paper, a new generic algorithm based on niche technique and local search method is presented under the consideration of inadequacies of the simple genetic algorithm. In order to prove the adaptability and validity of the improved genetic algorithm, optimization problems of multimodal functions with equal peaks, unequal peaks and complicated peak distribution are discussed. The simulation results show that compared to other niching methods, this improved genetic algorithm has obvious potential on many respects, such as convergence speed, solution accuracy, ability of global optimization, etc.

关键词： genetic algorithm (GA) niche technique local search method

Application of the annexation principle to the thermodynamic property study of ternary metallic melts In-Bi-Cu and In-Sb-Cu

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Journal of university of science and technology beijing 2002年第3期9卷 170-176页

作者： Man ZhangMetallurgy school, university of science and technology beijing,{2. (Received 2.01-10-2.) Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the phase diagrams, measured activities and the annexationprinciple, calculating models of mass action concentrations for In-Bi-Cu and In-Sb-Cu melts havebeen formulated. Calculated results not only agree well with practical values, but also obey themass action law, showing that the deduced model can reflect the structural reality of given meltasand that the annexation principles is applicable to these tow ternary metallic melts. So long asthere is one from three binary systems constituting the ternary melts, in which the activities ofone component exhibit positive deviation relative to Raoultian behavior, heterogeous meltsinevitably would form, so heterogeneous calculating model should be used to calculate their massaction concentrations. On the contrary, if all the binary melts are homogeneous and their activitiesexhibit negative deviation with respect to the Raoult's law, then the ternary melts formed fromthem will certainly be homogeneous, hence single phase model should be applied.

关键词： activity mass action concentration coexistence theory annexationprinciple

Prediction of Enthalpies of Fusion for Divalent Rare Earth Halides Based on Modeling by Artificial Neural Networks and Pattern Recognition

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 24-26页

作者： Yimin Sun Zhiyu Qiao Minghong He(Applied science school, {2. of science & technology beijing, beijing 100083. china)(National Natural science Foundation of china, beijing 100083. china) Applied science school University of Science and Technology Beijing Beijing 100083 China National Natural science Foundation of china Beijing 100083 China

The artificial neural network (ANN) and the pattern recognition were applied to study the correlation of enthalpies of fusion for divalent rare earth halides with their microstructural parameters,such as ionic radius and electronegativity. The model,represented by a back-propagation netal network, was trained with a 12.set of published data for divalent rare earth halides and then was used to predict the unknown ones. Also the criterion equations were ptesented to determine the enthalpies of fuSion for divalent rare earth halides using pattern recognition in mis work. The results from the model in ANN and criterion equations are in very good agreement with reference data.

关键词： BP neural network pattern recognition enthalpy of fusion divalent rare earth halides microstructural parameters

Numerical Simulation on Irregular Shrinkage of Initial Shell in Continuous Casting of Steel

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 103-106页

作者： Dejun Jing Kaike Cai(Metallurgy school, university of science and technology beijing,{2.) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the microstructures of steel, a thermo-elasto-plastic stress model of continuously casting billets is established to study hailal solidifying process in molds. Results show that peritectic phase transformation contributes greatly to the irregular shrinkage ofinitial shell, which makes the billets vulnerable to surface defects.

关键词： thermo-elasto-plastic stress model peritectic phase transformation irregular shrinkage of initial shell

Assessment of the apparent activation energies for gas/solid reactions—carbonate decomposition

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Journal of university of science and technology beijing 2003年第2期10卷 25-29页

作者： Jianhua Liu and Jiayun ZhangMetallurgical Engineering school, university of science and technology beijing,{2. Metall. Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The guidelines for assessing the apparent activation energies of gas/solidreactions have been proposed based on the experimental results from literatures. In CO_2.free inletgas flow, CaCO_3.decomposition between 950 and 12.0 K with thin sample layer could be controlled bythe interfacial chemical reaction with apparent activation energy E = (2.5+-10) KJ/mol and E=(2.0+-10) kJ/mol at T = 813.to 102. K, respectively. With relatively thick sample layer between 793.nd 12.3.K, the CaCO_3.decomposition could be controlled by one or more steps involvingself-cooling, nucleation, intrinsic diffusion and heat transfer of gases, and E could vary between147 and 190 kJ/mol. In CO_2.containing inlet gas flow (5 percent-100 percent of CO_2., E wasdetermined to be varied from 949 to 2.97 kJ/mol. For SrCO_3.and BaCO_3.decompositions controlled bythe interfacial chemical reaction, E was (2.3.-15) kJ/mol (1000-13.0K) and (3.5+-15) kJ/mol(12.0-1400 K), respectively

关键词： assessment activation energy decomposition carbonate

Thermodynamic Properties of Mn-P and Fe-Mn-P Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 10-13页

作者： Jian Zhang Rong Zhu Metallurgy school, university of science and technology beijing,{2. Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams and the coexistence theory of metallic melts structure involving compound formation, the cal- culating models of mass action concentrations for Mn-P and Fe-Mn-P melts have been formulated. The calculated mass action concen- trations agree well with the corresponding measured activities, this in turn shows that the deduced models can reflect the structural char- acteristics of the melts concerned and there isn't any saturation of phosphorus in both melts.

关键词： activity dephosphorization the coexistence theory mass action concentration

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma school of Computer science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-2.M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method