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Effect of Fe/Cu/Ce loading on the coal-based activated carbons for hydrolysis of carbonyl sulfide

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Journal of Rare Earths 2010年第2期28卷 205-210页

作者：宁平于丽丽易红宏唐晓龙李华王红妍杨丽娜 faculty of Environmental science and Engineering Kunming University of Science and Technology

Fe/Cu/Ce modified coal-based activated carbon(AC) was prepared by the sol-gel method,and the effect of Fe/Cu/Ce on catalytic properties of Fe/AC,Fe-Cu/AC and Fe-Cu-Ce/AC was investigated in the hydrolysis of carbonyl sulfide(COS) at 50 °*** surface properties were evaluated by means of nitrogen adsorption and were characterized by using scanning electron microscopy(SEM),X-ray diffracto-metry(XRD) and X-ray photoelectron spectroscopy(XPS).The catalytic activities results showed that addition of Cu and Ce...

关键词： carbonyl sulfide activated carbons metal oxides rare earths

Development of samarium–cobalt rare earth permanent magnetic materials

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Rare Metals 2014年第6期33卷 633-640页

作者： Jian-Hong Yi faculty of Materials science and Engineering Kunming University of Science and Technology

Samarium–cobalt rare-earth（Sm–Co-RE） permanent magnetic materials with large magnetic energy product, high coercive force, high Curie temperature, good thermal stability, and corrosion resistance, have wide potential applications in aerospace, microwave communications, instrumentation, electrical engineering, magnetic machinery, etc. In this paper, the development of Sm–CoRE permanent magnetic materials in the following aspects in recent years was summarized： Sm–Co-RE permanent magnets with high application temperatures, positive temperature coefficients of coercive force, zero temperature coefficients of residual magnetization, high resistance rate,high mechanical property, and nanocrystallization.

关键词： Samarium–cobalt rare-earth permanent magnet Magnetic Temperature coefficient Resistivity

Metal loaded zeolite adsorbents for hydrogen cyanide removal

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Journal of Environmental sciences 2013年第4期25卷 808-814页

作者： Ping Ning Juan Qiu Xueqian Wang Wei Liu Wei Chen faculty of Environmental science and Engineering Kunming University of Science and Technology

Metal （Cu, Co, or Zn） loaded ZSM-5 and Y zeolite adsorbents were prepared for the adsorption of hydrogen cyanide （HCN） toxic gas. The results showed that the HCN breakthrough capacity was enhanced significantly when zeolites were loaded with Cu. The physical and chemical properties of the adsorbents that influence the HCN adsorption capacity were analyzed. The maximal HCN breakthrough capacities were about the same for both zeolites at 2.2 mol of HCN/mol of Cu. The Cu2p XPS spectra showed that the possible species present were Cu2O and CuO. The Nls XPS data and FT-IR spectra indicated that CN- would be formed in the presence of Cu＋/Cu2＋ and oxygen gas, and the reaction product could be adsorbed onto Cu/ZSM-5 zeolite more easily than HCN.

关键词： hydrogen cyanide zeolite removal

Securing Recommender Systems Against Shilling Attacks Using Social-Based Clustering

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Journal of Computer science & technology 2013年第4期28卷 616-624页

作者：张响亮 Tak Man Desmond Lee Georgios Pitsilis King Abdullah University of science and technology faculty of science Technology and Communication University of Luxembourg

Abstract Recommender systems （RS） have been found supportive and practical in e-commerce and been established as useful aiding services. Despite their great adoption in the user communities, RS are still vulnerable to unscrupulous producers who try to promote their products by shilling the systems. With the advent of social networks new sources of information have been made available which can potentially render RS more resistant to attacks. In this paper we explore the information provided in the form of social links with clustering for diminishing the impact of attacks. We propose two algorithms, CLUTR and WCLUTR, to combine clustering with ＂trust＂ among users. We demonstrate that CLuTR and WCLUTR enhance the robustness of RS by experimentally evaluating them on data from a public consumer recommender system ***.

关键词： shilling attack recommender system collaborative filtering social trust clustering

Effects of Rare Earth,Titanium,and Magnesium Additions on Microstructures and Properties of High-boron Medium-carbon Alloy

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Journal of Iron and Steel Research International 2016年第11期23卷 1226-1233页

作者： Xiao-li SHI Ye-hua JIANG Rong ZHOU faculty of Materials science and Engineering Kunming University of Science and Technology

In order to improve the toughness and wear resistance of high-boron medium-carbon alloy （HBMCA）, a novel wear-resistant HBMCA comprising granular borocarbide was obtained by titanium, magnesium, and rare earth modifications. These modifications gave rise to greatly refined as-cast eutectic borocarbide structures and a less interconnected continuous borocarbide network. Heat treatment mostly produced broken and spheriodized borocarbides that tended to exist as isolated particles in modified HBMCA. The heat treated modified HBMCA exhibited enhanced hardness than pristine and impact toughness was improved significantly to 12.5 J/cm^2. In addition, it displayed 2.39 and 1.7 times greater wear resistance than high-speed steel （HSS） and high nickel-chromium alloy steel （Cr25） at high temperature （500℃）, respectively. Here, the modification mechanisms involving Re2O3, TiN, and MgO/ MgS heterogeneous nuclei were discussed.

关键词： modification eutectic borocarbide spheroidization toughness wear resistance

Microstructure and Properties of 7075Al Alloy Fabricated by Directly Combined of Spray Forming and Continuous Extrusion Forming under Different Atomization Gas Pressures

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 804-812页

作者： Ye-Gao Chen Yi Zhong Jiang-Cheng Yin Li-Qiang Wang Li-Na Liu Huan Yang Ying-Li Liu faculty of Materials science and Engineering Kunming University of Science and Technology

A new process consisting of the spray forming and the continuous extrusion forming for manufacturing 7075A1 alloy was proposed. The microstructure evolution, mechanical properties and the resistance to stress corrosion cracking of the alloy were studied. The results indicate that the spray forming process induces obviously grain refinement and greatly lower segregation microstructure. Besides, the Conform process produces finer grains and conduces to more uniform distribution of the precipitates of A1Cu and MgZn2 phases. The fabricated alloy shows good comprehensive mechanical properties and superb performance of stress corrosion resistance. Moreover, a better combination of the mechanical properties and the resistance to stress corrosion cracking could then be obtained under a certain condition of atomization gas pressure of 0.19 MPa. The enhanced properties are attributed to the following factors, which include the grain refinement, the fine and homogeneous distribution of A1Cu and MgZn2 phases, the high density of the extruded products, as well as the discontinuous distribution of the grain boundaries after retrogression and reaging （RRA） heat treatment.

关键词： 7075A1 alloy Spray forming Continuous extrusion forming Microstructure Property

An Attribute-Based Signcryption Scheme and Its Application in Information Hiding

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Chinese Journal of Electronics 2016年第4期25卷 632-640页

作者： PENG Changgen WANG Weiru TIAN Youliang YUAN Zhilong College of Computer science and technology Guizhou University faculty of science and technology University of Macau

In order to provide a secure,reliable and flexible way to hide information,a new attribute-based signcryption scheme based on ciphertext-policy and its security proof are *** scheme not only can simultaneously fulfil both authentication and confidentiality in an efficient way,but also implements a hierarchical decryption in one group and also between different groups according to user’s authority(different users satisfying the same access structure can be considered as a group).We provide a solution to information hiding using our proposed scheme which can embed ciphertext into a *** the hierarchical decryption property,different users will obtain different message from the same *** user can not get any information without private key because message existed in the carrier is *** solution can be applied in sharing important message under the public network.

关键词： Attribute-based signcryption Information hiding Access structure Hierarchical decryption

Co/Co7Fe3 heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc–air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第02期 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao Yu Zhang Aihua Yuan Hu Zhou School of Materials science and Engineering Jiangsu University of Science and Technology School of Environmental and Chemical Engineering Jiangsu University of Science and Technology

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction（ORR） and oxygen evolution reaction（OER） is crucial for developing rechargeable zinc–air batteries（ZABs）. Herein, an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere（NCS） decorated with dual-phase Co/Co7Fe3heterojunctions（CoFe@NCS）. The phase composition of materials has been adjusted by controlling the alloying degree. The optimal CoFe0.08@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm-2for OER in an alkaline electrolyte. The intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co7Fe3alloy and metallic Co species. When the CoFe0.08@NCS material is used as air–cathode catalyst of rechargeable liquid-state zinc–air battery（ZAB）, the device shows a high peak power-density(157 mW·cm-2) and maintains a stable voltage gap over 150 h, outperforming those of the benchmark（Pt/C+RuO2）-based device. In particular, the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending conditions. Our work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

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Landau-Zener Tunnelling of Two-Component Bose-Einstein Condensates in Optical Lattices

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Communications in Theoretical Physics 2010年第7期54卷 101-106页

作者：彭娉李冠强 faculty of science Shaanxi University of Science and Technology

We investigate the Landau-Zener tunnelling of two-component Bose-Einstein condensates （BECs） in optical lattices. In the neighborhood of the Brillouin zone edge, the system can be reduced to two coupled nonlinear two-level models. From the models, we calculate the change of the tunnelling probability for each component with the linear sweeping rate. It is found that the probability for each component exhibits regular oscillating behavior for the larger sweeping rate, but for smaller rate the oscillation is irregular. Moreover, the asymmetry of the tunnelling between the two components can be induced by the unbalanced initial populations or the inequality of the two self-interactions when the cross-interaction between the components exists. The result can not be found in the single component BECs.

关键词： Landau Zener tunnelling two-component Bose Einstein condensates optical lattices