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Properties of ten-year-aged argon oxygen decarburization stainless steel slag

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Journal of Iron and Steel Research International 2021年第10期28卷 1233-1242页

作者： Ya-jun Wang Ya-nan Zeng jun-guo li Yu-zhu Zhang Wei Wang College of Metallurgy and Energy North China University of Science and TechnologyTangshan063210HebeiChina School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina

The characteristics of argon oxygen decarburization slag(AODS)for smelting stainless steel that has been aged for 10 years were *** types of AODSs distributed at three positions in a slag heap were sampled for comparison *** analysis,mineral phase identification,thermogravimetric analysis,and micromorphology analysis were used to study the element migration trends and carbonation behavior of AODS after long-term *** leaching tests were performed to study the chromium leachability of the aged *** results show that during the long-term aging process,the AODS heap had undergone oxidation and carbonation,accompanied by element migration and mineralogical *** surface slag had the highest degree of carbonation but the weakest chromium *** chemical composition of the middle slag was the closest to that of the original *** the bottom steel slag,in addition to magnesium,certain depositions of other elements were *** matrix phases in the aged slag were dicalcium silicate and merwinite,and the chromium was mainly wrapped in these matrix phases in the form of oxides,spinels,or *** the combined effects of carbonation and oxidation,the leaching characteristics of the chromium in the aged slag varied greatly depending on the *** bottom slag had the strongest chromium leachability,and the hexavalent chromium had long-term continuous leachability.

关键词： Argon oxygen decarburization slag Aging Chromium Leaching Mineral phase

Kinetic model of chromium release from argon oxygen decarburisation(AOD)slag in a neutral leachate

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Journal of Iron and Steel Research International 2020年第11期27卷 1303-1310页

作者： Ya-nan Zeng Qian-qian Ren Bao liu jun-guo li School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063200HebeiChina

Valorisation of argon oxygen decarburisation(AOD)slag,a suitable recycling resource,is limited by the release of a notable amount of heavy metals,such as *** mineralogical component of AOD slag was characterised by X-ray diffraction and scanning electron microscopy-energy-dispersive X-ray *** explore the release kinetics of chromium from AOD slag,neutral leaching tests were performed at various *** results indicated the existence of two leaching stages:quick and slow leaching *** 2 h,the chromium release fraction increased sharply as the leaching time *** the leaching time in creased,the chromium release rate gradually *** on the shrinking core model,chromium release kinetic models for the quick and slow leaching stages from the AOD slag were independently *** chromium release was controlled by solid product diffusion during the quick leaching stage and a complicated process in the slow leaching *** activation energy of chromium leaching was calculated based on the Arrhenius *** product diffusion was the velocity-determining step during the 2 h leaching *** the slow leaching stage,chromium release was controlled by complicated hybrid control dominated by solid product diffusion.

关键词： Kinetic model Chromium release Shrinking core model-AOD slag

Componentwise Complementary Cycles in Multipartite Tournaments

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Acta Mathematicae Applicatae Sinica 2012年第1期28卷 201-208页

作者： Zhi-hong HE guo-jun li Xue-qin ZHOU School of Mathematics and Information Science Yantai UniversityYantai 264005China School of Mathematics and System Sciences Shandong UniversityJinan 250100China

The problem of complementary cycles in tournaments and bipartite tournaments was completely solved. However, the problem of complementary cycles in semicomplete n-partite digraphs with n 〉 3 is still open. Based on the definition of componentwise complementary cycles, we get the following result. Let D be a 2-strong n-partite （n 〉 6） tournament that is not a tournament. Let C be a 3-cycle of D and D ／ V（C） be nonstrong. For the unique acyclic sequence D1, D2,..., Da of D ／ V（C）, where a 〉 2, let Dc = {Di｜Di contains cycles, i = 1,2,...,a}, Dc = {D1,D2,...,Da} ／ De. If Dc≠ 0, then D contains a pair of componentwise complementary cycles.

关键词： complementary cycles componentwise complementary cycles multipartite tournaments

Lepton-Flavor Violating Processes li → ljγ in Topcolor-Assisted Technicolor Models

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Communications in Theoretical Physics 2002年第10期38卷 461-464页

作者： YUE Chong-Xing XU Qing-jun liU guo-li CCAST World Laboratory P.O. Box 8730 Beijing 100080 China College of Physics and Information Engineering Henan Normal University Xinxiang 453002 China College of Physics and Information Engineering Henan Normal University Xinxiang 453002 China College of Physics and Information Engineering Henan Normal University Xinxiang 453002 China

We consider the lepton-flavor violating (LFV) processes li → ljγ in the framework of topcolor-assistedtechnicolor (TC2) models. We find that the new gauge boson Z' predicted by TC2 models can give significantlycontributions to these processes via the flavor-changing couplings Z'lilj. The present experimental bound on the LFVprocess μ→ eγ gives severe constraints on the TC2 models. Using other experimental constraints on the Z' mass Mz,we obtain constraints on the lepton mixing factors KTμ and KTe. The future LFV experiments will probe into TC2models.

关键词： lepton flavor, topcolor-assisted technicolor (TC2)

Leaching behavior and mineralogical evolution of vanadium released from sodium roasted-acid leaching tailing of vanadium slag

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Journal of Iron and Steel Research International 2022年第5期29卷 772-782页

作者： Bao liu Jin li Qian-qian Ren Shuang Cai Xue Yang Ya-nan Zeng jun-guo li College of Metallurgy and Energy North China University of Science and TechnologyTangshan063210HebeiChina

The sodium roasted-acid leaching tailing(SRALT)of vanadium slag with a certain amount of vanadium exhibits potential environmental *** investigate the leaching behavior of vanadium from the SRALT,neutral batch leaching tests were *** evolution of vanadium concentration,pH,redox potential(Eh),dissolved oxygen,and conductivity as a function of time was *** diagrams of V–H2O system with different vanadium concentrations were obtained to identify the ionic speciation of vanadium in leachate.X-ray diffraction,X-ray photoelectron spectroscopy,field emission-scanning electron microscopy,and thermogravimetry–differential scanning calorimetry analysis were conducted to investigate the mineralogical evolution of the SRALT during the leaching *** was found that the major minerals of the original SRALT are titanomagnetite,spinel,olivine,and *** valence states of V existing in the original SRALT are V^(3+)and V^(5+).The pH and Eh values of the obtained leachates are 10.00–10.58 and(−43)–(+67)mV,*** this pH and Eh region,the released vanadium is mainly present as HVO_(4)^(2−).The FeOOH and CaCO_(3)would form during the leaching *** HVO_(4)^(2−)would be mainly adsorbed by the FeOOH and slightly incorporated into the CaCO_(3),resulting in the decline in the vanadium *** vanadium concentration above 27 mg L^(−1)and the dissolved oxygen value below 5.0 mg L^(−1)can be obtained after a short leaching *** a V(V)-releasing and oxygen-depleting substance,the leaching toxicity of the SRALT should not be ignored.

关键词： Vanadium Vanadium slag Tailing Leaching toxicity Mineralogical analysis

Modification for prediction model of austenite grain size at surface of microalloyed steel slabs based on in situ observation

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Journal of Iron and Steel Research International 2021年第9期28卷 1133-1140页

作者： Da-chao Fu Guang-hua Wen Xue-qin Zhu jun-li guo Ping Tang College of Materials Science and Engineering Chongqing UniversityChongqing400044China

The initial solidification process of microalloyed steels was simulated using a confocal scanning laser microscope,and the growth behavior of austenite grain was observed in *** method for measuring the initial austenite grain size was studied,and the M_(0)^(*)(the parameter to describe the grain boundary migration)values at different cooling rates were then calculated using the initial austenite grain size and the final grain ***,a newly modified model for predicting the austenite grain size was established by introducing the relationship between M_(0)^(*)and the cooling rate,and the value calculated from the modified model closely corresponds to the measured value,with average relative error being less than 5%.Further,the relationship between T^(γ)(the starting temperature for austenite grain growth)and equivalent carbon content C_(P)(C_(P)>0.18%)was obtained by in situ observation,and it was introduced into the modified model,which expanded the application scope of the *** the continuous casting slab produced by a steel plant as the experimental object,the modified austenite grain size prediction model was used to predict the austenite grain size at different depths of oscillation mark on the surface of slab,and the predicted value was in good agreement with the actual measured value.

关键词： In situ observation Microalloyed steel Austenite grain size Prediction model Oscillation mark depth

The optimal time-frequency atom search based on a modified ant colony algorithm

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Optoelectronics Letters 2008年第3期4卷 227-230页

作者： guo jun-feng li Yan-jun YU Rui-xing ZHANG Ke College of Astronautics Northwestern Polytechnical University Xi＇ an 710072China

this paper, a new optimal time-frequency atom search method based on a modified ant colony algorithm is proposed to improve the precision of the traditional methods. First, the discretization formula of finite length time-frequency atom is inferred at length. Second; a modified ant colony algorithm in continuous space is proposed. Finally, the optimal time- frequency atom search algorithm based on the modified ant colony algorithm is described in detail and the simulation experiment is carried on. The result indicates that the developed algorithm is valid and stable, and the precision of the method is higher than that of the traditional method.

关键词：最优化频率原子计算方法

Efficient Synthesis of Octalone

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Chemical Research in Chinese Universities 2007年第3期23卷 276-279页

作者： ZHANG Chen CHEN Jin-chun ZHENG guo-jun li Yu-lin State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China

A highly efficient and convergent approach for the synthesis of octalone 1, the focal intermediate for the synthesis of several sesquiterpenoids, was developed based on the cationic cyclization strategy of the functio... 详细信息

关键词： Octalone (± )-1β,11-Dihydroxy-△^4-eudesmol Cationic cyclization Sesquiterpenoids Total synthesis

Large margin classification for combatingdisguise attacks on spam filters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第3期13卷 187-195页

作者： Xi-chuan ZHOU Hai-bin SHEN Zhi-yong HUANG guo-jun li College of Communications Engineering Chongqing UniversityChongqing40044China Institute of VLSI Design Zhejiang UniversityHangzhou 310027China Chongqing Communication Institute Chongqing 400032China

This paper addresses the challenge of large margin classification for spare filtering in the presence of an adversary who disguises the spam mails to avoid being detected. In practice, the adversary may strategically add good words indicative of a legitimate message or remove bad words indicative of spam. We assume that the adversary could afford to modify a spam message only to a certain extent, without damaging its utility for the spammer. Under this assumption, we present a large margin approach for classification of spare messages that may be disguised. The proposed classifier is formulated as a second-order cone programming optimization. We performed a group of experiments using the TREC 2006 Spam Corpus. Results showed that the performance of the standard support vector machine （SVM） degrades rapidly when more words are injected or removed by the adversary, while the proposed approach is more stable under the disguise attack.

关键词： Large margin Spam filtering Second-order cone programming (SOCP) Adversarial classification