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进口血竭与国产血竭的比较性研究

广东化工 2015年第4期42卷 18-19,17页

作者：阿拉丁郭亚苹李丽于瑞霞司岩岩丁立新佳木斯大学药学院黑龙江省生物药制剂重点实验室黑龙江佳木斯154007

比较进口血竭药材与国产血竭药材的色谱图,并建立高效液相色谱法(HPLC)测定不同产地血竭中龙血素A和龙血素B的含量,为血竭药材质量控制提供有效的方法。采用超声波提取法,通过HPLC法对不同产地血竭进行比较,其色谱条件:Agilent Zorbax S... 详细信息

比较进口血竭药材与国产血竭药材的色谱图,并建立高效液相色谱法(HPLC)测定不同产地血竭中龙血素A和龙血素B的含量,为血竭药材质量控制提供有效的方法。采用超声波提取法,通过HPLC法对不同产地血竭进行比较,其色谱条件:Agilent Zorbax SB-C18色谱柱,流动相为:A乙腈,B 0.4%磷酸水,梯度洗脱,流速为1 m L/min,柱温为室温,检测波长为280 nm,记录时间60 min,进样量10μL。国产血竭与进口血竭,两者高效液相色谱图差异明显,进口血竭中龙血素A和龙血素B的含量明显高于国产血竭。

关键词：龙血素A 龙血素B HPLC法梯度洗脱

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang si Liu YiHua He Chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation(AKR)is a common radio emission,which can contribute to the magnetosphere−ionosphere−atmosphere *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500−4500 km and invariant latitude(|ILAT|)=60°−80°has been analyzed.63045 AKR samples have been identified with~48%(52%)samples on the dayside(nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05−08 and 18−22(02−05 and 12−17)in the northern(southern)*** distinct MLT asymmetry is associated with the direction of Bxof the interplanetary magnetic *** addition,the occurrence rate on the nightside clearly increases as the index *** study further enriches *** and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

Nanotribological properties and scratch resistance of MoS_(2)bilayerona siO_(2)/si substrate

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Friction 2023年第1期11卷 154-164页

作者： si-hwan KIM Hyo-sok AHN Department of Transdisciplinary Studies Seoul National UniversitySeoul 08826Republic of Korea Department of Manufacturing Systems and Design Engineering Seoul National University of Science and TechnologySeoul 08826 Republic of Korea

The tribological properties and scratch resistance of MoS_(2)bilayer deposited on siO_(2)/si substrates prepared via chemical vapor deposition are *** force microscopy(FFM)is employed to investigate the friction and wear properties of the MoS_(2)bilayer at the nanoscale by applying a normal load ranging from 200 to 1,000 *** resistance is measured using the scratch mode in FFM based on a linearly increasing load from 100 to 1,000 *** probe force microscopy(KPFM)is performed to locally measure the surface potential in the tested surface to qualitatively measure the wear/removal of Mos,layers and identify critical loads associated with the individual failures of the top and bottom *** analysis of the contact potential difference values as well as that of KPFM,friction,and height images show that the wear/removal of the top and bottom layers in the MoS_(2)bilayer system occurred *** FFM and KPFM results show that the top MoS_(2)layer begins to degrade at the end of the low friction stage,followed by the bottom layer,thereby resulting in a transitional friction stage owing to the direct contact between the diamond tip and siO_(2)*** the stable third stage,the transfer of lubricious MoS_(2)debris to the tip apex results in contact between the MoS_(2)-transferred tip and siO_(2).Nanoscratch test results show two ranges of critical loads,which correspond to the sequential removal of the top and bottom layers.

关键词： chemical vapor deposition(CVD)-grown MoS,bilayer friction force microscopy(FFM) nanoscratch test Kelvin probe force microscopy(KPFM) scratch resistance

Enhanced Ferromagnetism of CrI3 Bilayer by Self-Intercalation

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Chinese Physics Letters 2020年第10期37卷 114-119页

作者： Yu Guo Nanshu Liu yanyan Zhao Xue Jiang si Zhou Jijun Zhao MOE Key Laboratory of Materials Modification by Laser Ion and Electron BeamsDalian University of TechnologyDalian 116024China

Two-dimensional(2D)ferromagnets with high Curie temperature have long been the pursuit for electronic and spintronic *** 3 is a rising star of intrinsic 2D ferromagnets,however,it suffers from weak exchange *** we propose a general strategy of self-intercalation to achieve enhanced ferromagnetism in bilayer CrI *** show that filling either Cr or I atoms into the van der Waals gap of stacked and twisted CrI 3 bilayers can induce the double exchange effect and significantly strengthen the interlayer ferromagnetic *** to our first-principles calculations,the intercalated native atoms act as covalent bridge between two CrI 3 layers and lead to discrepant oxidation states for the Cr *** theoretical results offer a facile route to achieve high-Curie-temperature 2D magnets for device implementation.

关键词： exchange twisted ferromagnetic

参与食品可追溯体系对农户绿色生产转型的影响

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西北农林科技大学学报（社会科学版） 2025年第1期25卷 89-100页

作者：陈哲李晓静司伟西北农林科技大学经济管理学院陕西杨凌712100 烟台大学经济管理学院山东烟台264005 中国农业大学经济管理学院北京100083

基于2022年山东和陕西2省6县(市、区)1 248户苹果种植户的微观调查数据,在使用有限混合模型(FMM)测度农户绿色生产转型程度的基础上,实证检验参与食品可追溯体系对农户绿色生产转型的影响。研究结果表明:(1)参与食品可追溯体系会显著促... 详细信息

基于2022年山东和陕西2省6县(市、区)1 248户苹果种植户的微观调查数据,在使用有限混合模型(FMM)测度农户绿色生产转型程度的基础上,实证检验参与食品可追溯体系对农户绿色生产转型的影响。研究结果表明:(1)参与食品可追溯体系会显著促进农户绿色生产转型,这一结论在解决潜在的内生性问题和经过多种稳健性检验后依然成立;(2)异质性分析表明,参与食品可追溯体系对大规模种植户、参与组织和受教育水平更高的农户绿色生产转型的促进作用更为明显;(3)机制分析结果表明,参与食品可追溯体系可以通过产品收益激励、绿色认知提升、社会声誉维护三条路径影响农户绿色生产转型。据此提出加大食品可追溯体系建设,提高农户参与比率;明晰转型关键制约因素,增强农户绿色生产转型意愿;充分考虑不同资源禀赋农户特征,给予针对性的政策引导等对策建议。

关键词：食品可追溯体系绿色生产转型溢价激励随机前沿模型苹果种植户

Corrosion behavior of Gd_(2)Zr_(2)O_(7)thermal barrier coatings under Fe-containing environmental sediment attack

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Journal of Advanced Ceramics 2024年第4期13卷 447-462页

作者： Lei Guo yanyan Li Kai Yan School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Advanced Joining Technology Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin 300072China Key Laboratory of Special Equipment Safety and Energy-saving for State Market Regulation China Special Equipment Inspection&Research InstituteBeijing 100029China

Environmental sediments mainly consisting of CaO–MgO–Al_(2)O_(3)–siO_(2)(CMAS)corrosion are a serious threat to thermal barrier coatings(TBCs),in which Fe element is usually ***_(2)Zr_(2)O_(7)TBCs are famous for their excellent CMAS *** this study,the characteristics of Fe-containing environmental sediments(CMAS-Fe)and their corrosiveness to Gd_(2)Zr_(2)O_(7)coatings were *** types of CMAS-Fe glass with different Fe contents were *** melting points were measured to be 1322–1344℃,and the high-temperature viscosity showed a decreasing trend with increasing Fe *** corrosion behavior of four types of CMAS-Fe to Gd_(2)Zr_(2)O_(7)coatings at 1350℃was *** the initial corrosion stage(0.1 h),anorthite was precipitated in CMAS-Fe with a high Ca:si ratio,while Fe-garnet was formed in the melt with the highest Fe *** the corrosion time resulted in the formation of a reaction layer,which exhibited an interpenetrating network composed of Gd-oxyapatite,ZrO_(2),and residual *** spinel was precipitated within the reaction *** 1 h or even longer time,the reaction layers tended to be stable and compact,which had comparable hardness and fracture toughness to those of Gd_(2)Zr_(2)O_(7)*** the cyclic CMAS-Fe attack,the residual CMAS-Fe in the interpenetrating network provided a pathway for the redeposited CMAS-Fe infiltration,resulting in the continuous growth of the reaction *** a result,the Gd_(2)Zr_(2)O_(7)coatings had a large consumption in the thickness,degrading the coating ***,the Gd_(2)Zr_(2)O_(7)coatings exhibit unsatisfactory corrosion resistance to CMAS-Fe attack.

关键词： thermal barrier coatings(TBCs) Gd_(2)Zr_(2)O_(7) Fe-containing CaO-MgO-Al2O3-siO_(2)(CMAS) corrosion resistance reaction layer

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产业匹配视角下的环京产研一体化圈建设策略

河北学刊 2025年第1期45卷 82-90页

作者：张可云黎思灏中国人民大学应用经济学院

打造环京产研一体化圈层是推动京津冀协同发展的创新举措,需要推动北京市制造业高新技术企业与环京区县的合作。但环京区县存在产业基础薄弱、与北京产业匹配度不高和产业投资联系不强的问题。两地发展差距过大、市郊铁路建设滞后和环... 详细信息

打造环京产研一体化圈层是推动京津冀协同发展的创新举措,需要推动北京市制造业高新技术企业与环京区县的合作。但环京区县存在产业基础薄弱、与北京产业匹配度不高和产业投资联系不强的问题。两地发展差距过大、市郊铁路建设滞后和环京区县营商环境不良是造成上述问题的主要原因。未来应当根据产业匹配度建立对口合作关系,进一步加强市际交通基础设施建设,降低企业营商成本。

关键词：京津冀环京区县产研一体高新技术企业上市公司异地投资

Wear Resistance of Austenitic Steel Fe–17Mn–6si–0.3C with High silicon and High Manganese

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Acta Metallurgica sinica(English Letters) 2014年第2期27卷 352-358页

作者： Haitao si Renlong Xiong Fan Song Yuhua Wen Huabei Peng School of Manufacturing Science and Engineering Sichuan University

To solve the problem of poor wear resistance in conventional Hadfield steels under medium and low stress, a new kind of steel with high silicon and high manganese Fe-17Mn-6si-0.3C was designed and its wear resistance was studied. The results showed that it exhibited better wear resistance than conventional Hadfield steel in both dry friction and abrasive friction. The better wear resistance of the new steel with high silicon and high manganese resulted from the stressinduced γ→ε martensitic transformation.

关键词： High manganese steel Fe-Mn based alloys Wear resistance Martensitic transformation

Electromagnetic modification of faceted-faceted Ni_(31)si_(12)-Ni_2si eutectic alloy

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Chinese Science Bulletin 2012年第13期57卷 1595-1599页

作者： LU YiPing LI GuoBin DU yanyan JI YanShuo JIN Qun LI TingJu School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China Marine Engineering College Dalian Maritime UniversityDalian 116026China

In an electromagnetic field, the morphology of a binary faceted-faceted (FF) Ni31si12-Ni2si eutectic microstructure and the alloy's mechanical properties were investigated. Hardness experiments demonstrated that the solidified ingots were significantly strengthened, and the hardness was improved to 63.1 and 786.6 on the Rockwell hardness C and Vickers hardness scales, respectively. Tests of friction and wear in stirred FF eutectic alloys showed excellent anti-fatigue and anti-adhesion wear performance. Alloy changed from an anomalous microstructure to a refined quasi-regular structure, and there was an increase in the lamellar microstructure fraction. The formation process of the refined quasi-regular microstructure and the resulting mechanical properties were investigated.

关键词：共晶合金电磁改性力学性能硬度实验微观结构共晶组织维氏硬度洛氏硬度