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High Temperature Thermoelectric Properties of Dy-doped CaMnO_3 Ceramics

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Journal of Materials Science & Technology 2014年第8期30卷 821-825页

作者： Bin Zhan Jinle Lan yaochun liu Yuanhua Lin Yang Shen Cewen Nan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua University School of Materials Science and Engineering University of Science and Technology Beijing

Dy-doped CaMnO3 ceramics have been synthesized by co-precipitation method combined with the solid-state *** composition and microstructure analysis indicate that high density and pure CaMnO3 phase can be *** electric conductivity can be enhanced by Dy doping,and result in a slight increase of the thermal *** highest dimensionless figure of merit ZT of 0.15 has been obtained at 973 K for x = 0.02 sample,which is about 4 times larger than that of the pure CaMnO3,which indicate that CaMnO3can be a promising candidate for n-type thermoelectric material at high temperature.

关键词： CaMnO3 Thermoelectric properties Thermal conductivity

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立面与透视:文艺复兴时期意大利城市的街道

四川大学学报（哲学社会科学版） 2014年第2期 5-13页

作者：刘耀春四川大学历史文化学院四川成都610064

在中世纪晚期和文艺复兴时期(1300-1600),意大利城市的街道形态发生了许多重要变化。这主要表现为:注重街道的平整和路面铺砌(尤其是连接重要公共活动区域的主街道);强调街道"立面"的塑造,即街道两边宫邸立面的"装饰"性和风格的协调一致... 详细信息

在中世纪晚期和文艺复兴时期(1300-1600),意大利城市的街道形态发生了许多重要变化。这主要表现为:注重街道的平整和路面铺砌(尤其是连接重要公共活动区域的主街道);强调街道"立面"的塑造,即街道两边宫邸立面的"装饰"性和风格的协调一致;此外,文艺复兴晚期还出现了新的街道美学原则,即注重透视效果的笔直街道。文艺复兴时期的街道形态的变化与这一时期城市社会结构、文化观念等的变化交织在一起,并对后来意大利和欧洲城市建设产生了深远影响。

关键词：文艺复兴意大利城市街道

雅各布·布克哈特与意大利文艺复兴——对《意大利文艺复兴时期的文化》的再思考

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四川大学学报（哲学社会科学版） 2011年第1期 34-50页

作者：刘耀春四川大学历史文化学院四川成都610064

雅各布·布克哈特是现代西方文化史学的奠基者之一,他的《意大利文艺复兴时期的文化》被公认为诠释文艺复兴的经典著作。但长期以来,该书在国内学界却一直被严重误读。我们只有将布克哈特置于其生活的时代,并通过对当时史学潮流及布克... 详细信息

雅各布·布克哈特是现代西方文化史学的奠基者之一,他的《意大利文艺复兴时期的文化》被公认为诠释文艺复兴的经典著作。但长期以来,该书在国内学界却一直被严重误读。我们只有将布克哈特置于其生活的时代,并通过对当时史学潮流及布克哈特独特史学观念的剖析方能重新解读这部经典著作。

关键词：雅各布·布克哈特文艺复兴意大利欧洲

A New Full Solar Light Active Photocatalyst Bi Cu Se O and its Photocatalytic Mechanism

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A New Full Solar Light Active Photocatalyst Bi Cu Se O and i...

马来酸酐接枝聚乙烯黏合树脂对尼龙6的黏接性能

第十九届全国高技术陶瓷学术年会

作者： Huanchun Wang Shun Li yaochun liu Jinxuan Ding Yuan-Hua Lin Ben Xu

Photocatalysis is attracting enormous interest driven by the great promise of addressing current energy and environmental crises by converting solar light directly into chemical energy. However, efficiently harvesting solar energy for photocatalysis remains a pressing challenge, and the charge kinetics and mechanism of the photocatalytic process is far from being well understood. Here we report a new full solar spectrum driven photocatalyst in the system of a layered oxyselenide BiCuSeO with good photocatalytic activity for degradation of organic pollutants and chemical stability under light irradiation, and the photocatalytic performance of BiCuSeO can be further improved by band gap engineering with introduction of La. Our measurements and density-functional-theory calculations reveal that the effective mass and mobility of the carriers in BiCuSeO can be tuned by the La-doping, which are responsible for the tunable photocatalytic activity. Our findings may offer new perspectives for understanding the mechanism of photocatalysis through modulating the charge mobility and the effective mass of carriers and provide a guidance for designing efficient photocatalyst.

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来源： cnki会议评论

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塑料工业 2022年第4期50卷 84-89页

作者：刘嘉贤谢兴宇刘耀春佛山(华南)新材料研究院广东佛山528200 佛山清粤新材料科技有限公司广东佛山528200

使用双螺杆熔融接枝制备了一系列马来酸酐接枝聚乙烯(PE-g-MA),相对接枝率范围从0.081~0.281。进一步将PE-g-MA和未经改性的线型低密度聚乙烯(LLDPE)共混制备黏合树脂,采用热压复合的方法研究其对PE/尼龙6(PA6)复合膜和PA6/PA6复合膜的... 详细信息

使用双螺杆熔融接枝制备了一系列马来酸酐接枝聚乙烯(PE-g-MA),相对接枝率范围从0.081~0.281。进一步将PE-g-MA和未经改性的线型低密度聚乙烯(LLDPE)共混制备黏合树脂,采用热压复合的方法研究其对PE/尼龙6(PA6)复合膜和PA6/PA6复合膜的黏接性能。当PE-g-MA的相对接枝率为0.081时,黏合树脂对PA6的剥离强度随PE-g-MA含量增加而增大;PE-g-MA含量为100%时对PE/PA6和PA6/PA6的剥离强度分别为60 N/cm和40 N/cm。提高PE-g-MA的接枝率,黏合树脂对PA6的剥离强度会随PE-g-MA含量增加而先增后减。PE-g-MA的含量为100%时黏合树脂对PA6的剥离强度随PE-g-MA接枝率升高而下降。通过表面全反射红外光谱(ATR-FTIR)表征复合膜剥离后的PA6表面的残余氨基含量,相比复合前最高下降46.5%。氨基残余量越少,剥离强度越大,MA基团和PA6端氨基的反应程度是影响剥离强度的直接因素。

关键词：马来酸酐接枝聚乙烯尼龙6 黏接性能复合膜

不同nLi/nM值制备富锂锰基正极材料及其电化学性能

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材料导报 2019年第A01期33卷 50-52页

作者：封平净卢鹏刘耀春何玉林淮安新能源材料技术研究院储能材料实验室淮安223005 江苏财经职业技术学院机械电子与信息工程学院淮安223003

以NiSO4·6H2O、CoSO4·7H2O、MnSO4·H2O为原料,碳酸钠为沉淀剂,合成球形富锂前驱体,分别以1.00、1.01、1.02、1.03、1.04、1.05和1.06的锂元素与金属元素的化学计量比nLi/nM(锂元素与过渡金属总物质的量比,其中M为Ni、Co、Mn)值混锂,... 详细信息

以NiSO4·6H2O、CoSO4·7H2O、MnSO4·H2O为原料,碳酸钠为沉淀剂,合成球形富锂前驱体,分别以1.00、1.01、1.02、1.03、1.04、1.05和1.06的锂元素与金属元素的化学计量比nLi/nM(锂元素与过渡金属总物质的量比,其中M为Ni、Co、Mn)值混锂,与碳酸锂混合烧结后,制备了不同nLi/nM值的富锂锰基正极材料Li1.5Ni0.25Mn0.65Co0.1O2.5。电化学性能测试结果表明:nLi/nM值为1.05的富锂正极材料的电化学性能优异,循环性能较好,在2.0~4.8V电压窗口下,0.1C倍率首次放电比容量为276mAh/g,1C倍率下200圈循环后的容量保持率为83.7%。

关键词：锂离子电池 nLi/nM值富锂锰基正极材料电化学性能

Crystallined Hybrid Carbon Synthesized by Catalytic Carbonization of Biomass and in-situ Growth of Carbon Nanofibers

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Journal of Materials Science & Technology 2014年第5期30卷 466-472页

作者： Shuhe liu Shuchun Zhao yaochun Yao Peng Dong Chao Yang National Engineering Research Center of Waste Recovery Kunming University of Science and Technology Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

Crystallined hybrid carbon was synthesized by the catalytic carbonization of biomass （Pinus kesiya sawdust） at 1100 ℃ and in-situ growth of carbon nanofibers （CNFs） at 750 ℃ from acetylene. The microstructure of the composite was characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, transmission electron microscopy （TEM） and high-resolution transmission electron microscopy （HRTEM）. It was found that highly crystallined carbon composed of well-aligned graph℃ene layers with interlayer spacing of 0.34 nm can be formed by catalytic carbonization of biomass. However, the structure of the in-situ growing CNFs is lessaligned. Based on the results of the investigation, the formation mechanism of the crystallined hybrid carbon was discussed. Owning to synergistic effect of the highly crystallined carbon and the conductive network formed by CNFs, the crystallined hybrid carbon shows 32.6% lower electrical resistivity than biocarbon. When being used as anode material of lithium-ion batteries （LIBs）, the crystallined hybrid carbon and the biocarbon have nearly the same first coulombic efficiencies （CEs）, however, the former has a discharge capacity of 67% higher than the latter since the second cycle.

关键词： Carbon nanofibers Biomass Catalytic carbonization Lithium-ion batteries

Effect of Pore Structures on the Electrochemical Performance of Porous Silicon Synthesized from Magnesiothermic Reduction of Biosilica

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Journal of Wuhan University of Technology(Materials Science) 2016年第5期31卷 965-971页

作者：刘树和 liu Bin YAO yaochun DONG Peng ZHAO Shuchun National Engineering Research Center of Waste Recovery Kunming University of Science and Technology Kunming 650093 China' School of Material Science and Engineering Kunming University of Science and Technology Kunming 650093 China Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming 650093 China

Two kinds of porous silicon（PS） were synthesized by magnesiothermic reduction of rice husk silica（RHS） derived from the oxidization of rice husks（RHs）. One was obtained from oxidization/reduction at 500 ℃ of the unleached RHs, the other was synthesized from oxidization/reduction at 650 ℃ of the acidleached RHs. The structural difference of the above PS was compared： the former had a high pore volume（PV, 0.31 cm3/g） and a large specific surface area（SSA, 45.2 m^2/g）, 138 % and 17 % higher than the latter, respectively. As anode materials for lithium ion batteries, the former had reversible capacity of 1 400.7 m Ah/g, 987 m Ah/g lower than the latter; however, after 50 cycles, the former had 64.5 % capacity retention（907 m Ah/g）, which was 41.2 % higher than the latter（555.7 m Ah/g）. These results showed that the electrochemical performance of PS was significantly affected by its pore structures, and low reduction temperature played the key role in increasing its porosity, and therefore improving its cycling performance.

关键词： rice husks porous silicon lithium-ion batteries magnesiothermic reduction

Bearing Fault Diagnosis Based on Deep Discriminative Adversarial Domain Adaptation Neural Networks

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2619-2640页

作者： Jinxi Guo Kai Chen Jiehui liu Yuhao Ma Jie Wu yaochun Wu Xiaofeng Xue Jianshen Li School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan056000China College of Mechanical Engineering Anyang Institute of TechnologyAnyang455000China Department of Mechanical and Electrical Engineering Yuncheng UniversityYuncheng044000China

Intelligent diagnosis driven by big data for mechanical fault is an important means to ensure the safe operation ofequipment. In these methods, deep learning-based machinery fault diagnosis approaches have received increasingattention and achieved some results. It might lead to insufficient performance for using transfer learning alone andcause misclassification of target samples for domain bias when building deep models to learn domain-invariantfeatures. To address the above problems, a deep discriminative adversarial domain adaptation neural networkfor the bearing fault diagnosis model is proposed (DDADAN). In this method, the raw vibration data are firstlyconverted into frequency domain data by Fast Fourier Transform, and an improved deep convolutional neuralnetwork with wide first-layer kernels is used as a feature extractor to extract deep fault features. Then, domaininvariant features are learned from the fault data with correlation alignment-based domain adversarial ***, to enhance the discriminative property of features, discriminative feature learning is embeddedinto this network to make the features compact, as well as separable between classes within the class. Finally, theperformance and anti-noise capability of the proposedmethod are evaluated using two sets of bearing fault *** results demonstrate that the proposed method is capable of handling domain offset caused by differentworkingconditions and maintaining more than 97.53% accuracy on various transfer tasks. Furthermore, the proposedmethod can achieve high diagnostic accuracy under varying noise levels.

关键词： Fault diagnosis transfer learning domain adaptation discriminative feature learning correlation alignment