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CeAu_(2)In_(4):A candidate of quasi-one-dimensional antiferromagnetic Kondo lattice

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Chinese Physics B 2021年第8期30卷 152-157页

作者： Meng Lyu hengcan zhao Jiahao Zhang Zhen Wang Shuai Zhang Peijie Sun Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

Needle-like single crystals of CeAu_(2)In_(4)have been grown from In flux and characterized as a new candidate of quasi-one-dimensional Kondo lattice compound by crystallographic,magnetic,transport,and specific-heat measurements down to very low *** observe an antiferromagnetic transition at T_(N)≈0.9 K,a highly non-mean-field profile of the corresponding peak in specific heat,and a large Sommerfeld coefficientγ=369 mJ·mol^(-1)·K^(-2).The Kondo temperature T_(K)is estimated to be 1.1 K,being low and comparable to *** Fermi liquid behavior is observed deep into the magnetically ordered phase,the Kadowaki-Woods ratio is much reduced relative to the expected value for Ce compounds with Kramers doublet ground ***,this feature shares striking similarities to that of the prototypical quasi-one-dimensional compounds YbNi_(4)P_(2) and CeRh_(6)Ge_(4) with tunable ferromagnetic quantum critical *** the shortest Ce-Ce distance along the needle direction,CeAu_(2)In_(4)appears to be an interesting model system for exploring antiferromagnetic quantum critical behaviors in a quasi-one-dimensional Kondo lattice with enhanced quantum fluctuations.

关键词： heavy fermion quasi-one-dimensional Kondo lattice magnetic phase transition

Unusual thermodynamics of low-energy phonons in the Dirac semimetal Cd_(3)As_(2)

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Chinese Physics B 2022年第10期31卷 268-272页

作者： Zhen Wang hengcan zhao Meng Lyu Junsen Xiang Qingxin Dong Genfu Chen Shuai Zhang Peijie Sun Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Science University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

By studying the thermal conductivity,specific heat,elastic modulus,and thermal expansion as a function of temperature for Cd_(3)As_(2),we have unveiled a couple of important thermodynamic features of the low-energy phonons strongly interacting with Dirac *** existence of soft optical phonons,as inferred from the extremely low thermal conductivity,is unambiguously confirmed by low-temperature specific heat revealing significant deviation from Debye's *** estimated Debye temperature is small in the range of 100-200 K and varies significantly depending upon the measurement used in its experimental *** thermodynamic Gr¨uneisen ratioγreveals a remarkable reduction below about 100 K,an energy scale that is highly relevant to the Dirac states,towards negative values below about 10 K that are indicative of lattice instability.

关键词： Dirac semimetal low-energy phonon thermal conductivity lattice instability

Pressure effect in the Kondo semimetal CeRu4Sn6 with nontrivial topology

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Chinese Physics B 2018年第9期27卷 477-481页

作者： Jiahao Zhang Shuai Zhang Ziheng Chen Meng Lv hengcan zhao Yi-feng Yang Genfu Chen Peijie Sun Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 1O0190 China University of Chinese Academy of Sciences Beijing 100049 China

Kondo semimetal CeRu4Sn6 is attracting renewed attention due to the theoretically predicted nontrivial topology in its electronic band structure. We report hydrostatic and chemical pressure effects on the transport properties of single- and poly-crystalline samples. The electrical resistivity p （T） is gradually enhanced by applying pressure over a wide temperature range from room temperature down to 25 mK. Two thermal activation gaps estimated from high- and low-temperature windows are found to increase with pressure. A flat p（T） observed at the lowest temperatures below 300 mK appears to be robust against both pressure and field. This feature as well as the increase of the energy gaps calls for more intensive investigations with respect to electron correlations and band topology.

关键词： CeRu4Sn6 Weyl semimetal heavy fermion hydrostatic pressure

响应面法优化大蝎子草水溶性总黄酮提取工艺及其水提液抗氧化活性分析

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贵州科学 2022年第6期40卷 31-36页

作者：董贺李军晋海军唐晓琴赵泽林孙恒灿张丽艳贵州中医药大学贵州贵阳550025

目的:优化大蝎子草水溶性总黄酮提取工艺,并对其水提液抗氧化活性进行分析。方法:以浸泡时间、料液比和提取时间为影响因素,大蝎子草水溶性总黄酮含量为评定指标,设计响应面实验。通过DPPH和ABTS自由基清除实验,对大蝎子草水提液的抗氧... 详细信息

目的:优化大蝎子草水溶性总黄酮提取工艺,并对其水提液抗氧化活性进行分析。方法:以浸泡时间、料液比和提取时间为影响因素,大蝎子草水溶性总黄酮含量为评定指标,设计响应面实验。通过DPPH和ABTS自由基清除实验,对大蝎子草水提液的抗氧化活性进行分析。结果:大蝎子草水溶性总黄酮的最佳提取工艺为浸泡时间65 min、料液比1∶19、提取时间70 min,水溶性总黄酮含量为6.42±0.026 mg/g。大蝎子草水提液和VC溶液对DPPH自由基的最大清除率分别为73.38%和97.34%,IC_(50)值分别为59.616μg/mL和0.018μg/mL,大蝎子草水提液和VC溶液对ABTS自由基的最大清除率分别为99.38%和99.47%,IC_(50)值分别为12.086μg/mL和13μg/mL。结论:该方法简便、稳定、可行,可用于大蝎子草水溶性总黄酮的提取,且其水提液具有一定的抗氧化作用。

关键词：大蝎子草水溶性总黄酮 DPPH ABTS

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斜刃剪板机剪切能力测定与机架有限元分析

冶金设备 2001年第2期 9-11,38页

作者：史荣张恒昌孙斌煜常振罗李金英张小立赵金英燕山大学 066004 太原重型机械学院 030024 邯郸钢铁集团有限公司 056015

通过对邯郸钢铁 (集团 )有限公司中板厂斜刃剪板机剪切力及机架应力的现场实测与有限元分析 ,给出了大型剪切机剪切力的测试方法及测试结果 ,并采用有限元法对机架应力与变形进行了分析 ,找出了机架结构的薄弱环节。

关键词：剪板机实验研究有限元分析剪切能力斜刃机架

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续断盐炙工艺优化及其抗氧化活性研究

贵州科学 2023年第1期41卷 11-16页

作者：唐晓琴晋海军马四补李军董贺孙恒灿赵泽林汤小芳张丽艳贵州中医药大学贵州贵阳550025

目的:筛选续断盐炙最佳工艺,分析续断主产区四川省不同产地的续断盐炙前后抗氧化活性。方法:以川续断皂苷Ⅵ含量为评价指标,炒制温度、加盐量、炒制时间、闷润时间为考察因素,采用Box-Behnken响应面法优化续断盐炙工艺;通过DPPH自由基... 详细信息

目的:筛选续断盐炙最佳工艺,分析续断主产区四川省不同产地的续断盐炙前后抗氧化活性。方法:以川续断皂苷Ⅵ含量为评价指标,炒制温度、加盐量、炒制时间、闷润时间为考察因素,采用Box-Behnken响应面法优化续断盐炙工艺;通过DPPH自由基清除试验分析不同产地续断抗氧化活性。结果:最佳续断盐炙工艺为:炒制温度170℃、加盐量2.55%、炒制时间7.5 min、闷润时间60 min;盐炙后,盐边、沐川和盐源续断对DPPH自由基清除能力升高。结论:优化后续断盐炙工艺稳定可行,可为实际生产提供参考;不同产地续断抗氧化活性存在一定差异,盐炙对其抗氧化活性产生影响。

关键词：续断响应面法盐炙工艺抗氧化活性