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Corrosion behavior of a CuCrNiAl alloy in the presence of NaCl deposit

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Rare Metals 2006年第3期25卷 210-215页

作者： XU Tao chang limin LIU Jianhua Department of Applied Technology Daqing Petroleum Institute Daqing 163318 China Analysis and Measure Center Jilin Normal University Siping 136000 China Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China

The corrosion behavior of a CuCrNiAl alloy with NaCl deposit at 700 and 900℃ was studied by means of metalloscope, XRD, SEM/EDX, and thermogravimetric analysis. The results indicated that the corrosion of the CuCrNiAl alloy beneath the NaCl deposit is severe; the corrosion production is loose and easy to scale off; the Cr phase is easier to erode than the Cu phase, and the contents of Cu and Cr decrease when the content of Ni increases in the matrix of the alloy beneath the corrosion region. The effects of distortion on the corrosion of the CuCrNiAl alloy were discussed, and the acceleration mechanisms of NaCl on the corrosion were also discussed.

关键词： CuCrNiAl alloy corrosion NaCl high temperature

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声波移动障碍反散射问题研究

长春理工大学学报（自然科学版） 2024年第2期47卷 121-127页

作者：常丽敏孟品超长春理工大学数学与统计学院长春130022

研究一种具有Dirichlet边界条件的时域声波移动障碍反散射问题。首先对时域波动方程进行求解,在有限观测时间内对移动障碍物采集动态声波近场数据;其次建立一个时域声波移动障碍反散射问题的神经网络模型,该模型将时域近场数据作为输入... 详细信息

研究一种具有Dirichlet边界条件的时域声波移动障碍反散射问题。首先对时域波动方程进行求解,在有限观测时间内对移动障碍物采集动态声波近场数据;其次建立一个时域声波移动障碍反散射问题的神经网络模型,该模型将时域近场数据作为输入序列,已知形状的移动障碍物位置参数作为输出序列,求解该反散射问题;最后对于不同移动速度的情况,有效地反演出移动障碍物的位置和轨迹。数值实验表明了该方法的有效性。

关键词：时域声波反散射问题移动障碍物多层前馈神经网络近场数据

Electrochemical activation of oxygen atom of SnO2 to expedite efficient conversion reaction for alkaline-ion(Li+/Na+/K+)storages

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Nano Research 2023年第1期16卷 1642-1650页

作者： Yong Cheng Bingbing Chen limin chang Dongyu Zhang Chunli Wang Shaohua Wang Ping Nie limin Wang Key Laboratory of Preparation and Applications of Environmental Friendly Materials(Jilin Normal University) Ministry of EducationChangchun 130103China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryCASChangchun 130022China Department of Energy Science and Engineering Nanjing Tech UniversityNanjing 210000China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

SnO2-based anode materials have attracted much attention due to high capacity and relatively mild voltage ***,limited by low initial Coulombic efficiency(ICE)and poor stability,its practical application is still ***,it has been found that compositing carbon or metal particles with SnO2 is an effective strategy to achieve high alkaline-ion *** this strategy may improve the kinetics and ICE of the electrochemical reaction,the specific mechanism has not been clearly *** this work,we found that the invalidation SnO2 may go through two steps:1)the conversion process from SnO2 to Sn and Li2O;2)the collapse of the electrode material resulted from huge volume changes during the alloyed Sn with alkaline *** address these issues,a unique robust Co-NC shell derived from ZIF-67 is introduced,in which the transited metallic Co nanoparticles could accelerate the decomposition of Sn-O and Li-O bonds,thus expedite the kinetics of conversion *** a result,the SnO2@Co-NC electrode achieves a more complete and efficient transfer between SnO2 and Sn phases,possessing a potential to achieve high alkaline-ion(Li+/Na+/K+)storages.

关键词： alkaline-ion storage SnO2 anode conversion reaction electron transfer

Stabilizing effects of atomic Ti doping on high-voltage high-nickel layered oxide cathode for lithium-ion rechargeable batteries

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Nano Research 2022年第5期15卷 4091-4099页

作者： Yong Cheng Yan Sun changting Chu limin chang Zhaomin Wang Dongyu Zhang Wanqiang Liu Zechao Zhuang limin Wang Key Laboratory of Preparation and Applications of Environmental Friendly Materials(Ministry of Education) Jilin Normal UniversityChangchun 130103China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of materials science and engineering Changchun University of Science and TechnologyChangchun 130022China Department of Chemistry Tsinghua UniversityBeijing 100084China

High-voltage high-nickel lithium layered oxide cathodes show great application prospects to meet the ever-increasing demand for further improvement of the energy density of rechargeable lithium-ion batteries(LIBs)mainly due to their high output ***,severe bulk structural degradation and undesired electrode-electrolyte interface reactions seriously endanger the cycle life and safety of the ***,2 mol%Ti atom is used as modified material doping into LiNi_(0.8)Co_(0.2)Mn_(0.2O2)(NCM)to reform LiNi_(0.6)Co_(0.2)Mn_(0.18)Ti_(0.02)O_(2)(NCM-Ti)and address the long-standing inherent *** a high cut-off voltage of 4.5 V,NCM-Ti delivers a higher capacity retention ratio(91.8%vs.82.9%)after 150 cycles and a superior rate capacity(118 vs.105 mAh·g^(-1))at the high current density of 10 C than the pristine *** designed high-voltage full battery with graphite as anode and NCM-Ti as cathode also exhibits high energy density(240 Wh·kg^(-1))and excellent electrochemical *** superior electrochemical behavior can be attributed to the improved stability of the bulk structure and the electrode-electrolyte interface owing to the strong Ti-O bond and no unpaired *** in-situ X-ray diffraction analysis demonstrates that Ti-doping inhibits the undesired H2-H3 phase transition,minimizing the mechanical *** ex-situ TEM and X-ray photoelectron spectroscopy reveal that Ti-doping suppresses the release of interfacial oxygen,reducing undesired interfacial *** work provides a valuable strategic guideline for the application of high-voltage high-nickel cathodes in LIBs.

关键词： lithium-ion battery high-voltage high-nickel cathode Ti-doping structural stability interface stability

Low-cost hybrid integrated 4 × 25 GBaud PAM-4CWDM ROSA with a PLC-based arrayed waveguide grating de-multiplexer

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Photonics Research 2019年第7期7卷 37-42页

作者： Lei Liu limin chang Yingxin Kuang Zezheng Li Yang Liu Huan Guan Manqing Tan Yude Yu Zhiyong Li State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 101408China

We demonstrate a low-cost hybrid integrated and compact 100 GBaud four-lane coarse wavelength division multiplexing (CWDM) receiver optical sub-assembly (ROSA) based on an arrayed waveguide grating de-multiplexer in the O band. To achieve the horizontal light coupling between the planar light-wave circuit (PLC) based arrayed waveguide grating de-multiplexer and photodetector array, a 42°polished facet is applied for total reflection.A flexible printed circuit with high-frequency coplanar waveguides is used for a power supply of trans-impedance amplifier and signal *** fabricated CWDM ROSA module, whose size is 18mm×22mm×6mm, shows a 3 dB bandwidth of 21.2,18.4,19.6,and 19.3 GHz,respectively,in each lane. The overall symbol error rates are at a magnitude of 10^-7 for 25 GBaud four-level pulse amplitude modulation (PAM-4) transmission with an average input optical power of 5dBm.

关键词： CWDM ROSA division optical compact facet pulse dB

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控股股东股权质押与公司业绩预告行为

财经论丛 2020年第9期 74-83页

作者：常利民东北财经大学会计学院辽宁大连116025

以2007~2017年中国A股上市公司为研究样本,考察了控股股东股权质押对公司业绩预告行为的影响。研究发现,控股股东股权质押降低了公司业绩预告的自愿性和精确度,增加了业绩预告偏差;降低业绩预告精确度,增加业绩预告偏差的作用在强制披... 详细信息

以2007~2017年中国A股上市公司为研究样本,考察了控股股东股权质押对公司业绩预告行为的影响。研究发现,控股股东股权质押降低了公司业绩预告的自愿性和精确度,增加了业绩预告偏差;降低业绩预告精确度,增加业绩预告偏差的作用在强制披露业绩预告情形下更显著;降低业绩预告自愿性和精确度,增加业绩预告偏差的作用在审计质量较低企业中更显著。作用机制分析发现,控股股东股权质押降低业绩预告自愿性和精确度,增加业绩预告偏差的作用仅体现在卖空限制的公司;控股股东股权质押解除后,该作用不再显著。本文研究对于完善业绩预告制度和股权质押制度,维护资本市场稳定具有借鉴意义。

关键词：股权质押业绩预告信息披露

元宇宙场域下用户-知识-场景重构的图书馆服务机制创新与发展对策研究

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情报科学 2023年第6期41卷 170-181页

作者：常立民吉林省经济管理干部学院图书馆吉林长春130000

【目的/意义】元宇宙场域具有现实世界无法比拟的优势,探索元宇宙图书馆中用户、知识与场景的建构与运行能够为图书馆服务机制创新发展提供理论支持。【方法/过程】对元宇宙图书馆的使命与价值分析的基础上,对技术、用户、知识与场景的... 详细信息

【目的/意义】元宇宙场域具有现实世界无法比拟的优势,探索元宇宙图书馆中用户、知识与场景的建构与运行能够为图书馆服务机制创新发展提供理论支持。【方法/过程】对元宇宙图书馆的使命与价值分析的基础上,对技术、用户、知识与场景的重构过程与运行关系进行逻辑分析。【结果/结论】元宇宙场域下,用户、知识、场景成为元宇宙图书馆服务机制的平行构成要素,并在元宇宙场域下被重新定义和塑造,相互之间形成驱动-交互-生产-体验、参与-体验-建构、调用-发展等共生关系,推进图书馆用户参与建构、知识组织与生产、场景服务等服务机制的创新,并从思想观念转变、职能机构改革、运行过程重组、服务实践以点带面、向外拓展五个方面提出未来发展对策。【创新/局限】明确提出元宇宙图书馆中用户、知识与场景的共生关系,并以此创新用户参与建构机制、知识组织与生产机制、场景服务机制,但创新机制的实践过程还有待进一步探索与验证。

关键词：元宇宙元宇宙图书馆用户-知识-场景共生图书馆服务机制

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商誉减值与公司业绩预告行为

证券市场导报 2022年第1期 62-71页

作者：常利民中原工学院系统与工业工程技术研究中心/经济管理学院河南郑州451191

近年来,商誉减值引发的公司业绩“暴雷”风险成为资本市场的热点话题。本文基于中国A股上市公司数据,考察了商誉减值对业绩预告行为的影响。研究发现,商誉减值提高了公司自愿披露业绩预告积极性,但降低了业绩预告精确度和准确度。机制... 详细信息

近年来,商誉减值引发的公司业绩“暴雷”风险成为资本市场的热点话题。本文基于中国A股上市公司数据,考察了商誉减值对业绩预告行为的影响。研究发现,商誉减值提高了公司自愿披露业绩预告积极性,但降低了业绩预告精确度和准确度。机制检验表明,商誉减值通过增加双重代理成本降低业绩预告精确度和准确度;坏消息、卖空机制下,发生商誉减值的公司通过降低业绩预告精确度和准确度以维稳股价的动机更强。进一步分析表明,商誉减值降低业绩预告精确度、准确度的作用在内部控制质量较低、分析师跟踪较少的公司中更显著,在自愿披露公司与强制披露公司之间不存在显著差异。本文结论对政策制定中防范商誉减值风险、完善上市公司信息披露制度提供了实证证据。

关键词：商誉减值业绩预告信息披露代理成本

形变与热处理对CuCr合金中Cr相形貌及合金性能的影响

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稀有金属材料与工程 2005年第12期34卷 1952-1956页

作者：常立民肖莹郝文光吉林师范大学吉林四平136000 燕山大学河北秦皇岛066004 北京电力设备总厂北京102401

研究了CuCr合金在不同形变与热处理制度下,组织中Cr相形貌、合金力学性能及导电性能的变化。结果表明：当变形量达到70％时,合金中的Cr粒子产生严重的变形,且有开裂现象。在随后高温热处理过程中开裂的Cr粒子发生熔断和球化。适当的形... 详细信息

研究了CuCr合金在不同形变与热处理制度下,组织中Cr相形貌、合金力学性能及导电性能的变化。结果表明：当变形量达到70％时,合金中的Cr粒子产生严重的变形,且有开裂现象。在随后高温热处理过程中开裂的Cr粒子发生熔断和球化。适当的形变与热处理能改善CuCr合金的力学性能与导电性能,并从微观组织方面对其原因进行了分析。

关键词： CuCr合金形变与热处理 Cr相力学性能导电性能