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Electronic structure evolution accompanying heavy fermion formation in CeCu2Si2

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 123-131页

作者： XueBing luo Yun Zhang QiuYun Chen Qin Liu lizhu luo ShiYong Tan XieGang Zhu XinChun Lai Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621908China

The cooper pairs in the heavy-fermion superconductor CeCu2Si2 are formed of heavy ***,the heavy fermions are fundamental to the emergence of unconventional superconductivity and associated non-Fermi-liquid behavior in the normal *** interplay between localization and itinerancy manifested on the electronic structure is key for understanding the heavyfermion ***,via the first-principle density functional theory(DFT)combined with single-site dynamical mean-field theory(DMFT),we investigate the temperature(T)evolution of the electronic structure of CeCu2Si2 in the normal state,focusing on the role of the 4f states in the low energy *** characteristic temperature scales of this evolution,which accompanied the heavy-fermion formation,are *** coherence onset temperature is around 130K,whereas the heavy-fermion band formation temperature is between 40 and 80K;both characteristic temperature scales are higher than the transport coherence ***,the heavy-fermion formation is confirmed by calculating its effective mass variation with the *** on the calculated T-dependent evolution of the 4 f orbital occupancy and electronic structure,an explanation on the behavior of the temperature evolution of the correlation strength of CeCu2Si2 is *** results offer a comprehensive microscopic picture of the heavy-fermion formation in CeCu2Si2,which is essential for further understanding the emergent superconducting pairing mechanism.

关键词： CeCu2Si2 heavy-fermion formation temperature electronic structure DFT+DMFT

Study on Surface and Bulk Properties of Ce-5 % Lanthanum Alloy

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Journal of Rare Earths 2004年第Z1期22卷 22-25页

作者： luo lizhu Wang Xiaolin Fu Xiaoguo Zhang Yanzhi Zhao Zhengping Liu Chunrong China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China China Academy of Engineering Physics Mianyang 621900 China

The surface and bulk properties of Ce-5% La were studied with X-ray photoelectron spectroscopy (XPS)and X-ray diffraction (XRD), *** XRD analysis shows that cerium in bulk is in γ-phase, and its lattice parameter is 0.516 *** we also find Ce2O3 in the bulk from the XRD figure but no existence of metal lanthanum because of its small *** XPS analysis shows that there are always oxides existing in the *** O1s peak always exists at the binding energy of 530.3 eV, which may be attributed to Ce2O3 and La2O3, but no evidence was found for the existence of *** is concluded that there is a thick layer of Ce2O3 on the sample *** the Ce3d peak show multi-split in the figure, in which there are two peaks in each region, 3d5/2 and 3d3/2, and the binding energy of these peaks are 882.86, 887.70 eV for 3d5/2, and 901.44, 905.93 eV for 3d3/*** special phenomena can be attributed to the changes of 4f electronic configuration, and the cerium in the sample exhibits properties similar to *** the influence of the addition of lanthanum to cerium is not visible, and further investigations are expected.

关键词： Ce-5% lanthanum alloy XRD XPS rare earths

Direct observation of the f–c hybridization in the ordered uranium films on W(110)

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Chinese Physics B 2019年第7期28卷 444-448页

作者： Qiuyun Chen Shiyong Tan Wei Feng lizhu luo Xiegang Zhu Xinchun Lai Science and Technology on Surface Physics and Chemistry Laboratory

A key issue in metallic uranium and its related actinide compounds is the character of the f electrons, whether it is localized or *** we grew well ordered uranium films on a W(110) *** surface topography was investigated by scanning tunneling *** Fermi surface and band structure of the grown films were studied by angle-resolved photoemission *** spectral weight can be observed around the Fermi level, which mainly comes from the f ***, we provided direct evidence that the f bands hybridize with the conduction bands in the uranium ordered films, which is different from previously reported mechanism of the direct f–f *** propose that the above two mechanisms both exist in this system by manifesting themselves in different momentum *** results give a comprehensive study of the ordered uranium films and may throw new light on the study of the 5 f-electron character and physical properties of metallic uranium and other related actinide materials.

关键词： uranium films 5f-electron character angle-resolved photoemission spectroscopy

An investigation of the effects of dust storms on rat lung using HRCT and blood gas analysis

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Research in Cold and Arid Regions 2016年第4期8卷 319-324页

作者： FengFeng Lei WanYin luo ZhiBao Dong YingZhu Sang lizhu luo Gang Huang Hua Liu QiZhang Chen Department of Respiration the People's Hospital of Gansu Province Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Department of Radiation Imaging the People's Hospital of Gansu Province

The increasing intensity and frequency of sand-dust storms in China has led to greater prominence of associated environmentaland health issues. Many studies have focused on the health effects of air particulate contaminants, but fewformal investigations have studied the effects of sand-dust storms on human and animal health. The aim of this study wasto investigate the effects of dust storms on rat lung by using high resolution computed tomography （HRCT） and blood gasanalysis through a wind tunnel simulating. We found that the rat lung damage effects can be detected by the HRCT imagingafter exposure to sand-dust storm environments, but had no obvious result through blood gas analysis. Exposure durationspositively correlated with the damage degree to lung tissue. These will provide some evidence for clinical diagnosis ofnon-occupational pneumoconiosis.

关键词： dust storm lung blood gas analysis HRCT wind tunnel simulation

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高中课程改革与高考改革关系演变与展望

课程．教材．教法 2022年第3期42卷 62-71页

作者：罗立祝福建师范大学教育学部福州350117

新中国成立以来,我国高中课程改革与高考改革关系演变经历了创立与政治化、改革与错位、深化与协同三个发展阶段。高中课程育才与高考选才是两种不同性质的活动,高考科目仅是全部高中课程科目的一部分,高中课程标准也只是选择高考内容... 详细信息

新中国成立以来,我国高中课程改革与高考改革关系演变经历了创立与政治化、改革与错位、深化与协同三个发展阶段。高中课程育才与高考选才是两种不同性质的活动,高考科目仅是全部高中课程科目的一部分,高中课程标准也只是选择高考内容的依据之一,这导致二者形成错综复杂的关系。为了加快推进教育现代化、建设教育强国,建议健全高中课程实施的督查机制、增强高中学业水平考试功能与作用、优化高考科目设置、深化高考内容改革,以提升高中课程改革与高考改革的协同育人成效。

关键词：高中课程改革高考改革协同育人

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马缨丹提取物对黄胸散白蚁体内酶活性的影响

林业科学 2017年第5期53卷 107-115页

作者：孙骊珠罗兰袁忠林青岛农业大学农学与植物保护学院青岛266109

【目的】探究马缨丹氯仿提取物、乙酸乙酯和石油醚萃取物对黄胸散白蚁体内纤维素酶系及解毒酶系活性的影响,初步探讨其作用机制。【方法】采用滤纸片带毒饲喂,测定处理不同时间点其对黄胸散白蚁体内3种纤维素酶[内切-β-1,4-葡萄糖酶(EG... 详细信息

【目的】探究马缨丹氯仿提取物、乙酸乙酯和石油醚萃取物对黄胸散白蚁体内纤维素酶系及解毒酶系活性的影响,初步探讨其作用机制。【方法】采用滤纸片带毒饲喂,测定处理不同时间点其对黄胸散白蚁体内3种纤维素酶[内切-β-1,4-葡萄糖酶(EG)、外切-β-1,4-葡萄糖酶(CBH)、β-葡萄糖苷酶(BG)]和3种解毒酶[羧酸酯酶(Car E)、谷胱甘肽S-转移酶(GSTs)、多功能氧化酶(MFO)]酶活性的影响。【结果】马缨丹氯仿提取物、乙酸乙酯和石油醚萃取物在6~72 h对黄胸散白蚁体内6种酶活性的影响存在差异,主要表现为有一定的抑制作用。对3种纤维素酶活性的影响而言,氯仿提取物对EG酶活性无显著影响,但对CBH和BG酶有显著的抑制作用,尤其对CBH酶抑制作用较强,在72 h时抑制率最大,达17.61%;乙酸乙酯萃取物对3种酶均有抑制作用,对EG和BG酶活性抑制作用较强,在48 h时对EG的抑制率最大,为27.18%,在24 h时对BG酶活性抑制作用最大,为29.28%;石油醚萃取物对CBH酶活性无显著影响,但对其他2种酶抑制作用显著,对EG酶的抑制作用较强,在72 h时对此酶的抑制作用最大,为39.89%。对3种解毒酶活性影响而言,3种提取物对Car E酶的活性影响不大;对GSTs酶的影响主要在12~48 h,其中乙酸乙酯萃取物的抑制作用最强,36 h时抑制率最大,为39.54%;对FMO酶的抑制作用呈波动式变化,其中以12 h、36 h抑制作用较强。【结论】马缨丹氯仿提取物、乙酸乙酯和石油醚萃取物能抑制黄胸散白蚁体内的纤维素酶和解毒酶,扰乱其正常的生理代谢功能。

关键词：黄胸散白蚁马缨丹提取物纤维素酶解毒酶杀虫作用机制

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高校招生录取模式改革:目标、现状与展望

福建师范大学学报（哲学社会科学版） 2022年第3期 148-158页

作者：罗立祝福建师范大学教育学院福建福州350117

根据稳定匹配理论和高校招生参与主体的价值追求,高校招生录取模式的改革目标是实现考生个性特长与高校特色专业的稳定匹配。论文构建了专业契合性、形实兼顾性、简便易行性三个主要评价指标,通过对我国现有梯度志愿、院校平行志愿、“... 详细信息

根据稳定匹配理论和高校招生参与主体的价值追求,高校招生录取模式的改革目标是实现考生个性特长与高校特色专业的稳定匹配。论文构建了专业契合性、形实兼顾性、简便易行性三个主要评价指标,通过对我国现有梯度志愿、院校平行志愿、“院校+专业组”志愿、专业类平行志愿、“一档多投”、高校综合评价等六种招生录取模式优势与不足的比较分析,提出“一档多投”录取模式、专业(类)平行录取模式分别是最理想与较理想的招生录取模式。高校招生录取模式未来改革方向应是采用以高考成绩为主要标准、兼容考生多元个性特长标准的专业类平行志愿录取模式,增加高校与考生的双向选择权,引导学生发展个性特长,促进高校培养高质量多样化专业人才。

关键词：高校招生录取模式改革专业类一档多投

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新高考选考科目赋分方案再思考

河北师范大学学报（教育科学版） 2020年第4期22卷 14-20页

作者：罗立祝福建师范大学教育学部福建福州350117

2019年4月,河北、辽宁、江苏、福建、湖北、广东、重庆、湖南8个省市成为继2014年高考综合改革启动后的第三批试点省份,目前共有14个省市启动了高考综合改革。新一轮高考综合改革对高考科目设置作出重大制度创新,选考科目赋分改革成为... 详细信息

2019年4月,河北、辽宁、江苏、福建、湖北、广东、重庆、湖南8个省市成为继2014年高考综合改革启动后的第三批试点省份,目前共有14个省市启动了高考综合改革。新一轮高考综合改革对高考科目设置作出重大制度创新,选考科目赋分改革成为一个极具挑战的难题。这三批高考综合改革试点省市对选考科目如何赋分开展了试错式的改革探索,满足了考试分数正态分布转换和普通高校招生对高考分数区分度的要求,但未能很好解决不同选考科目之间分数转换的等值性和可比性的问题,无法阻止出现功利选科博弈现象。对此,建议尝试采用参照语数英统考成绩的动态比例转换赋分方案,进一步完善现有选考科目赋分方案。

关键词：新高考选考科目赋分方案区分度等值性

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金属铀的水蒸气腐蚀行为研究现状

材料导报 2017年第13期31卷 17-24,32页

作者：秦建伟罗丽珠帅茂兵表面物理化学重点实验室绵阳621700 中国工程物理研究院材料研究所绵阳621700

金属铀是一种重要的核材料,在国防工业和能源系统中得到广泛应用,由于其具有高化学活性,当贮存环境中含有微量水蒸气时容易发生腐蚀而影响其使用性能。为深入认识金属铀在含水环境中的腐蚀老化过程,研究人员开展了大量科学研究。围绕腐... 详细信息

金属铀是一种重要的核材料,在国防工业和能源系统中得到广泛应用,由于其具有高化学活性,当贮存环境中含有微量水蒸气时容易发生腐蚀而影响其使用性能。为深入认识金属铀在含水环境中的腐蚀老化过程,研究人员开展了大量科学研究。围绕腐蚀产物、腐蚀动力学以及腐蚀机理综述了国内外关于金属铀与水反应过程的主要研究成果,从氧化铀缺陷结构、金属铀微观结构对反应过程的影响以及O_2的氧化抑制机理等方面对下一步研究方向进行了展望。

关键词：铀水腐蚀产物腐蚀动力学腐蚀机理