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Structural determination of eleven new preschisanartane-type schinortriterpenoids from two Schisandra species and structural revision of preschisanartanin J using NMR computation method

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Chinese Journal of Natural Medicines 2019年第12期17卷 970-981页

作者： HU Kun li xing-ren TANG Jian-Wei li Xiao-Nian PUNO Pema-Tenzin State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences

Nineteen preschisanartane-type schinortriterpenoids(SNTs),among which eleven ones were previously undescribed,were isolated from two Schisandra species,*** and *** structures were determined using 1 D and 2 D NMR spectroscopic analyses,NMR data comparison,quantum chemical calculation of NMR parameters,electronic circular dichroism(ECD),X-ray single crystal diffraction,and chemical ***,structural re-examination of a few previously reported preschisanartane-type SNTs led to the structural revision of preschisanartanin ***,it is suggested that the reported structures of arisanlactone D and schilancidilactone W should be ***,a few isolated SNTs were found to possess neurite outgrowthpromoting activities,and protective activities against neural injuries.

关键词： Schisandra sphaerandra Schisandra rubriflora Preschisanartane-type schinortriterpenoids Structural revision Quantum chemical calculation of NMR parameters

Effects of Pulse Current on Solidification Structure of Austenitic Stainless Steel

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Journal of Iron and Steel Research International 2004年第6期11卷 37-39页

作者： FAN Jin-hui CHEN Yu li ren-xing ZHAI Qi-jie Shanghai University Hebei University of Science and Technology

The 1Cr18Ni9Ti specimens were treated respectively with pulse current under 520 V and 2 600 V during solidification and the solidification structure was *** results showed that pulse current can refine solidification grains,cut primary dentrities remarkably and reduce second dentritic arm *** mechanism and effect are changed with operation parameters.

关键词： pulse current austenitic stainless steel solidification structure

Influence of Electropulsing Pretreatment on Solid-State Graphitization of Spherical Graphite Iron

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Journal of Iron and Steel Research International 2012年第12期19卷 66-72页

作者： li Qing-chun li ren-xing liN Da-shuai CHANG Guo-wei ZHAI Qi-jie School of Materials Science and Engineering Liaoning University of Technology Jinzhou 121000 Liaoning China Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai 200072 China

The solid-state graphitization process of spherical graphite iron after electropulsing pretreatment was ob- served in-situ by using a high-temperature confocal scanning laser microscope （HTCSLM）. The influence of electro- pulsing pretreatment on the decomposition of cementite and the formation of graphite during the solid-state graphiti- zation was studied. The result indicates that the electropulsing pretreatment can accelerate the decomposition of ce mentite, and make more neonatal graphite in small size be formed near the cementite. The neonatal graphite nucle ates and grows chiefly at the temperature range of 800 to 850 ℃, and the average growth rate of neonatal graphite is 0. 034 μm2/s during the heating process. For the spherical graphite iron after normal and electropulsing pretreat- ment, the decomposition rate of cementite during the heating process is 0.16 and 0.24 μm2/s, respectively. Analy- sis shows that the electropulsing pretreatment promotes the dislocation accumulation near the cementite, conse- quently, the decomposition of cementite and the formation of neonatal graphite is accelerated during the solid-state graphitization.

关键词： pulse current spherical graphite iron graphitization cementite in-situ observation

Recent progress in CdS-based S-scheme photocatalysts

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Journal of Materials Science & Technology 2024年第4期171卷 162-184页

作者： Yajing ren Yunfeng li Guixu Pan Ning Wang Yan xing Zhenyi Zhang College of Environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China Jilin Provincial Key Laboratory of Advanced Energy Materials Department of ChemistryNortheast Normal UniversityChangchun 130024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further *** sulfide(CdS),as a typical reducing semiconductor of metal sulfides,represents an interesting research hotspot in photocatalysis due to its suitable bandgap(2.4 eV)for utilizing visible light and strong reducing ability for inducing surface catalytic ***,the photocatalytic performance of CdS is still limited by its fast carrier recombination and serious *** far,CdS semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel S-scheme heterojunction to overcome the above *** this review,the de-sign concepts,basic principles,and charge transfer characteristics of CdS-based S-scheme heterojunction photocatalysts have been comprehensively *** advanced and effective characterization methods for studying the mechanism of CdS-based S-scheme heterojunction are analyzed in ***-thermore,we also summarize the typical applications of CdS-based S-scheme heterojunctions for water splitting,CO_(2) reduction,pollutant degradation,***,according to the current investigation sta-tus,some drawbacks in the current synthetic strategy,mechanism exploration,and application prospect of CdS-based S-scheme heterojunction are proposed,which need to be addressed by further expansion and innovative research.

关键词： Photocatalysis CdS semiconductor Heterojunction S-scheme Metal sulfide

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六轴宽轨机车动力学特性研究

太原科技大学学报 2024年第2期45卷 166-171页

作者：黄凌雄史青录梁永刚李幸人太原科技大学机械工程学院太原030024 中车大同电力机车有限公司技术中心山西大同037038

建立六轴宽轨电力机车——“BKT-2型机车”的多体动力学仿真模型。在AAR5级轨道谱的激励下,研究不同的曲线半径和机车运行速度,以及悬挂刚度的变化对机车动力学特性的影响。结果表明:速度较大时,曲线半径越小垂向动荷系数越大;速度增加... 详细信息

建立六轴宽轨电力机车——“BKT-2型机车”的多体动力学仿真模型。在AAR5级轨道谱的激励下,研究不同的曲线半径和机车运行速度,以及悬挂刚度的变化对机车动力学特性的影响。结果表明:速度较大时,曲线半径越小垂向动荷系数越大;速度增加,不同曲线半径的垂向平稳性变化不大,横向平稳性变化明显;随着一系横向刚度的增大,横向平稳性指标减小,随着二系横向刚度的增大,横向平稳性指标增加;垂向刚度的变化对于垂向动力学特性有较大的影响。适当减小一系、二系垂向刚度,有利于提升机车动力学性能。

关键词：电力机车平稳性指标悬挂刚度垂向动荷系数

Challenges in li-ion battery high-voltage technology and recent advances in high-voltage electrolytes

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Journal of Energy Chemistry 2024年第4期91卷 73-98页

作者： Jianguo liu Baohui li Jinghang Cao Xiao xing Gan Cui Shandong Key Laboratory of Oil&Gas Storage and Transportation Safety College of Pipeline and Civil EngineeringChina University of Petroleum(East China)Qingdao 266580ShandongChina

The electrolyte directly contacts the essential parts of a lithium-ion battery,and as a result,the electrochemical properties of the electrolyte have a significant impact on the voltage platform,charge discharge capacity,energy density,service life,and rate discharge *** raising the voltage at the charge/discharge plateau,the energy density of the battery is ***,this causes transition metal dissolution,irreversible phase changes of the cathode active material,and parasitic electrolyte oxidation *** article presents an overview of these concerns to provide a clear explanation of the issues involved in the development of electrolytes for high-voltage lithium-ion ***,solidstate electrolytes enable various applications and will likely have an impact on the development of batteries with high energy *** is necessary to improve the high-voltage performance of electrolytes by creating solvents with high thermal stabilities and high voltage resistance and additives with superior film forming performance,multifunctional capabilities,and stable lithium *** offer suggestions for the future development of high-energy lithium-ion batteries,we conclude by offering our own opinions and insights on the current development of lithium-ion batteries.

关键词： lithium-ion battery High voltage Electrolyte additive Solid electrolyte

High-performance anisotropic SmCo-based magnet with novel microstructure

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Journal of Rare Earths 2024年第8期42卷 1539-1545,I0005页

作者： Yingchang li Zicao xing Nengjun Yu Zesong ren Minxiang Pan Qiong Wu Hongliang Ge Minggang Zhu Wei li College of Materials and Chemistry China jiliang UniversityHangzhou 310018China Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing 100081China

A novel micro structure of magnetically anisotropic Sm Co-based magnet with high-performance is *** magnet consists of SmCo_(7)-H(TbCu_(7)-hexagonal type),Sm_(2)Co_(17)-H(Th_(2)Ni_(17)-hexagonal type)and SmCo_(3)-R(SmCo_(3)-rhombohedral type)*** maximum magnetic energy product of the magnet is 231.69 kj/m^(3),and the intrinsic coercivity is 1005.47 kA/*** outstanding intrinsic coercivity temperature coefficient(β)of-0.125%/K between 298 and 773 K is obtained,which is very close to theβof commercial high-temperature Sm_(2)Co_(17)-based sintered *** initial magnetization curve indicates that the coercivity mechanism is controlled by a domain wall pinning *** SmCo_(3)-R lamellar phase may be a potential pinning center or self-pinning *** microstructure of the magnet is different from that of any previous SmCo-based *** findings provide a new idea for preparing high-performance SmCo-based permanent magnets.

关键词： Rare earths Permanent magnet Composite magnet Melt-spinning Microstructure

Effect of pulse magnetic field on solidification structure and properties of pure copper

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China Foundry 2007年第2期4卷 116-119页

作者： liAO Xi-liang GONG Yong-yong li ren-xing CHEN Wen-jie ZHAI Qi-jie School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Mechanical Engineering Shandong University Jinan 250061 China

The application of pulse magnetic field to metal solidification is an advanced technique which can remarkably refine solidification structure. In this paper, the effect of pulse magnetic field on solidification structure, mechanical properties and conductivity of pure copper was experimentally investigated. The results showed that the solidification structure transformed from coarse columnar crystal to fine globular crystal with increasing pulse voltage. Increasing pulse voltage also improved the tensile strength. However, with the increase of pulse voltage, the elongation and electrical resistivity firstly decreased, then increased when the pulse voltage beyond a critical value. Moreover, in some conditions, pulse magnetic field can simultaneously improve the conductivity and mechanical property of pure copper.

关键词： pure copper pulse magnetic field solidification structure property

Accelerating lithium-sulfur battery reaction kinetics and inducing 3D deposition of li_(2)S using interactions between Fe_(3)Se_(4)and lithium polysulfides

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Journal of Energy Chemistry 2024年第8期95卷 540-553,I0012页

作者： Yihan lin liheng li Longjie Tan Yongliang li Xiangzhong ren Peixin Zhang Chuanxin He lingna Sun College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060GuangdongChina

Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical application is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible deposition of li_(2)*** address these issues,a novel composite,using electrospinning technology,consisting of Fe_(3)Se_(4)and porous nitrogen-doped carbon nanofibers was designed for the interlayer of *** porous carbon nanofiber structure facilitates the transport of ions and electrons,while the Fe_(3)Se_(4)material adsorbs lithium polysulfides(liPSs)and accelerates its catalytic conversion ***,the Fe_(3)Se_(4)material interacts with soluble liPSs to generate a new polysulfide intermediate,li_(x)FeS_(y)complex,which changes the electrochemical reaction pathway and facilitates the three-dimensional deposition of li_(2)S,enhancing the reversibility of *** designed LSB demonstrates a high specific capacity of1529.6 mA h g^(-1)in the first cycle at 0.2 *** rate performance is also excellent,maintaining an ultra-high specific capacity of 779.7 mA h g^(-1)at a high rate of 8 *** investigation explores the mechanism of the interaction between the interlayer and liPSs,and provides a new strategy to regulate the reaction kinetics and li_(2)S deposition in LSBs.

关键词： lithium-sulfur batteries Polysulfide intermediates li_(2)S electrodeposition Interlayers Electrostatic spinning Adsorption Catalysis