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A novel norsesquiterpene alkaloid from the mushroom-forming fungus Flammulina velutipes

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Chinese Chemical Letters 2013年第1期24卷 57-58页

作者： zhen-Yu Xu zhi-ang Wu Kai-Shun bi School of Business Administration Shenyang Pharmaceutical University Center for Drug Evaluation SFDA

A new norsesquiterpe alkaloid （1） was isolated from the solid culture of mushroom-forming fungus Flammulina velutipes fermented on rice. The structure of I was elucidated by spectroscopic methods. The absolute confi... 详细信息

关键词： MushroomNorsesquiterpeneFlammulina velutipesCytotoxicity

A fringe jump counting method for the phase measurement in the HCN laser interferometer on EAST and its FPGA-based implementation

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Plasma Science and Technology 2024年第4期26卷 156-161页

作者：姚远杨曜提昂宋扬张家敏王琰张耀刘海庆揭银先 Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Anhui Electrical Engineering Professional Technique College Hefei 230022People’s Republic of China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601People’s Republic of China

Electron density in fusion plasma is usually diagnosed using laser-aided interferometers. The phase difference signal obtained after phase demodulation is wrapped, which is also called a fringe jump. A method has been developed to unwrap the phase difference signal in real time using FPGA, specifically designed to handle fringe jumps in the hydrogen cyanide(HCN) laser interferometer on the EAST superconducting tokamak. This method is designed for a phase demodulator using the fast Fourier transform(FFT) method at the front end. The method is better adapted for hardware implementation compared to complex mathematical analysis algorithms, such as field programmable gate array(FPGA). It has been applied to process the phase measurement results of the HCN laser interferometer on EAST in real time. Electron density results show good confidence in the fringe jump unwrapping method. Further possible application in other laser interferometers, such as the POlarimeter-INTerferometer(POINT)system on EAST tokamak is also discussed.

关键词： electron density laser-aided interferometer fringe jump unwrapping FPGA EAST

A three-way electrolyte with ternary solvents for high-energy-density and long-cycling lithium-sulfur pouch cells

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SusMat 2024年第2期4卷 1-12页

作者： zheng Li Legeng Yu Chen-Xi bi Xi-Yao Li JinMa Xiang Chen Xue-Qiang z.ang Aibing Chen Haoting Chen zuoru z.ang Li-zhen Fan Bo-Quan Li Cheng Tang Qiang z.ang Tsinghua Center for Green Chemical Engineering Electrification Beijing Key Laboratory of Green Chemical Reaction Engineering and TechnologyDepartment of Chemical EngineeringTsinghua UniversityBeijingChina School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Institute of Advanced Materials and Technology University of Science and TechnologyBeijingChina Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuanChina Center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan UniversityJangan-GuSuwon-SiGyeonggi-DoRepublic of Korea College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuangChina Ordos Carbon Neutral Research and Application Co. Ltd.Kangbashi DistrictOrdos CityInner MongoliaChina Institute for Carbon Neutrality Tsinghua UniversityBeijingChina

Lithium–sulfur(Li–S)batteries promise high-energy-density potential to exceed the commercialized lithiumion batteries but suffer from limited cycling lifespan due to the side reactions between lithium polysulfides(LiPSs)and Li metal ***,a three-way electrolyte with ternary solvents is proposed to enable high-energy-density and long-cycling Li–S pouch ***,ternary solvents composed of 1,2-dimethoxyethane,di-isopropyl sulfide,and 1,3,5-trioxane are employed to guarantee smooth cathode kinetics,inhibit the parasitic reactions,and construct a robust solid electrolyte interphase,*** cycling lifespan of Li–S coin cells with 50μm Li anodes and 4.0 mg cm^(−2) sulfur cathodes is prolonged from88 to 222 cycles using the three-way ***-heterogeneous solvation structure of LiPSs and organic-rich solid electrolyte interphase are identified to improve the cycling stability of Li metal ***,a 3.0 Ah-level Li–S pouch cell with the three-way electrolyte realizes a high energy density of 405 Wh kg^(−1) and undergoes 27 *** affords a three-way electrolyte recipe for suppressing the side reactions of LiPSs and inspires rational electrolyte design for practical high-energy-density and long-cycling Li–S batteries.

关键词： lithium metal anodes lithium-sulfur batteries pouch cells solid electrolyte interphase three-way electrolyte

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面向神经病学的智能预问诊系统研究及应用

中国卫生信息管理杂志 2024年第4期21卷 590-595页

作者：马大燕毕临风王子昂李瑞首都医科大学附属北京天坛医院信息管理与数据中心北京市100070

目的神经系统疾病具有诊疗复杂、类型多样、多数疾病患病率低等特点,为降低神经系统疾病基层医疗机构首诊难度,提升医院医疗服务质量和效率,开展面向神经病学的智能预问诊系统研究。方法在构建的神经系统疾病循证医学知识图谱基础上,... 详细信息

目的神经系统疾病具有诊疗复杂、类型多样、多数疾病患病率低等特点,为降低神经系统疾病基层医疗机构首诊难度,提升医院医疗服务质量和效率,开展面向神经病学的智能预问诊系统研究。方法在构建的神经系统疾病循证医学知识图谱基础上,通过循证医学规则引擎和规则流,利用人工智能技术构建智能预问诊系统。结果该系统采用人机交互的引导式问答方式采集患者病情、既往史等信息,自动生成预问诊报告发送给临床医生。上线应用的效果表明,该系统优化了医院诊疗服务流程,有效提高了医患沟通效率。结论该成果未来可应用到各级医疗机构,实现医院优质专科诊疗经验下沉基层,辅助基层规范化问诊。

关键词：神经系统疾病预问诊系统知识图谱规则引擎

NiS ultrafine nanorod with translational and rotational symmetry

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National Science Review 2024年第07期 218-225页

作者： Jianxin Kang Qi Hu Ruixuan z.ang ang Gao zhongning Huang ziming Su Ke Pei Qinghua z.ang Li-Min Liu Renchao Che Lin Gu Er-Jia Guo Lin Guo School of Chemistry Beihang University Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative Materials Academy for Engineering&Technology Fudan University zhejiang Laboratory Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials School of Materials Science and Engineering Tsinghua University Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physics Beihang University

Anisotropy is a significant and prevalent characteristic of materials, conferring orientation-dependent properties, meaning that the creation of original symmetry enables key functionality that is not found in nature. Even with the advancements in atomic machining, synthesis of separated symmetry in different directions within a single structure remains an extraordinary challenge. Here, we successfully fabricate NiS ultrafine nanorods with separated symmetry along two directions. The atomic structure of the nanorod exhibits rotational symmetry in the radial direction, while its axial direction is characterized by divergent translational symmetry, surpassing the conventional crystalline structures known to date. It does not fit the traditional description of the space group and the point group in three dimensions, so we define it as a new structure in which translational symmetry and rotational symmetry are separated. Further corroborating the atomic symmetric separation in the electronic structure, we observed the combination of stripe and vortex magnetic domains in a single nanorod with different directions, in accordance with the atomic *** manipulation of nanostructure at the atomic level introduces a novel approach to regulate new properties finely, leading to the proposal of new nanotechnology mechanisms.

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棕榈油在鱼类配合饲料中应用的研究进展

中国饲料 2024年第13期 101-108页

作者：闭然叶继丹集美大学水产学院厦门市饲料检测与安全评价重点实验室福建厦门361021

以中国为代表的全球水产养殖业发展迅猛,拉动了鱼油的强劲消费,从而造成鱼油持续供给短缺和价格上涨的局面,因此,寻求鱼油替代品已成为水产饲料领域的重要课题之一。棕榈油是一种种植面积广、产量大的植物油,已广泛应用于饲料、食品、... 详细信息

以中国为代表的全球水产养殖业发展迅猛,拉动了鱼油的强劲消费,从而造成鱼油持续供给短缺和价格上涨的局面,因此,寻求鱼油替代品已成为水产饲料领域的重要课题之一。棕榈油是一种种植面积广、产量大的植物油,已广泛应用于饲料、食品、化工、医药、生物质能和其他领域。本文综述了棕榈油在鱼类配合饲料中应用的研究进展,为合理配制鱼类配合饲料提供有益参考。

关键词：棕榈油鱼油替代鱼类饲料

双层单原子催化剂用于促进高活性和选择性电催化硝酸盐还原制氨

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物理化学学报 2024年第6期40卷 60-62页

作者：于镜坤雍雪曹昂卢思宇郑州大学化学学院绿色催化中心郑州450001 Department of Chemistry University of SheffieldSheffieldS37HFUK Department of Physics Technical University of DenmarkKongens Lyngby 2800Denmar

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSA... 详细信息

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSACs)进行了系统研究,通过轴向d-d轨道杂化提高了从SACs到BSACs的电催化硝酸盐还原反应(NO_(3)RR)的活性和选择性。考虑到可能的O端、N端、NO端和NO二聚体途径,计算结果显示,在单层SACs中,Ti-Pc和V-Pc分别具有优异的极限电位(U_(L)),分别为-0.24和-0.48V。形成能、溶解势以及从头算分子动力学结果表明,在反应条件下,这些催化剂非常稳定。在这些单层TM-Pc中,它们的d带能级和占据数受到d_(xz)/d^(yz)和p_(z)轨道杂化的影响。其轴向d_(z^(2))轨道的可用性通过形成d_(z^(2))-d_(z^(2))相互作用来进一步调整d带和反应性。在此基础上,以Ti-Pc和V-Pc为底物,通过形成轴向d-d轨道杂化来构建BSACs,为调节NO_(3)RR催化性能提供了一种独特的新途径。重要的是,我们发现d带中心(εd)、d_(xz)+d_(yz)轨道的占据数和U_(L)之间存在二维火山关系,用于描述它们的NO_(3)RR催化性能。最佳的BSACs应该同时具备适当的ε_(d)和d_(xz)+d_(yz)占用数。Ti-Mo和Ti-Ta被确定为出色的NO_(3)RR催化剂,其U_(L)均降低至-0.13 V。而d_(z^(2))-d_(z^(2))轨道之间的杂化则增强了双层金属之间的电荷转移和结构稳定性。缺乏相邻的金属位点将导致生成NO_(2)、NO和N_(2)的能垒较高,从而抑制副产物生成。最终,本研究揭示了在SACs和BSACs上对硝酸盐还原进行合理优化的方法,可为改进电催化剂的设计提供指导。

关键词：硝酸盐还原第一性原理计算单原子催化剂双层单原子催化剂轴向轨道杂化

Anion-induced electrolyte chemistry enables high energy density primary battery for ultralow-temperature conditions

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Science China Chemistry 2024年

作者： zi-Hang Xue Hao-Jie Liang Yong-Li Heng Jia-Lin Yang Edison Huixiang ang Hong-Yan Lü Hong Yu Dong-Mei Dai Dai-Huo Liu Chuan-Yu zheng Wei Guo Xing-Long Wu Department of Chemistry Northeast Normal University MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal University Natural Sciences and Science Education National Institute of Education Nanyang Technological University State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University School of Chemistry and Chemical Engineering Henan Normal University Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal University

Lithium/fluorinated-carbon（Li/CFx） primary batteries are widely used in defense and military fields due to their stable discharge plateau, low self-discharge rate, and adaptability across a wide temperature range. However, enhancing their overall energy density and discharge capacity at low temperatures remains a critical challenge. Herein, we report a strategically designed LiBF4-based sulfite/carboxylate electrolyte, where the anion-involved solvation structure significantly enhances electrochemical kinetics by reducing the desolvation barrier. Simultaneously, it introduces a radical reaction mechanism that contributes to additional capacity. As a result, the Li/CFxprimary batteries with this formulated electrolyte deliver a specific capacity of 2,257.15 mAh g-1at 25 °C. More importantly, when operating at -40 °C, the batteries exhibit an exceptionally high discharge capacity of 1,549.4 m Ah g-1and an energy density of 2,868.6 Wh kg-1. Even at -60 °C, the Li/CFxcells achieve a specific capacity of 444.3 mAh g-1and an energy density of 821.8 Wh kg-1at 0.1 C, significantly outperforming previously reported organic-based liquid electrolytes. This work offers a viable strategy for enhancing the specific capacity and energy density of primary batteries in extreme environments, providing valuable insights for future developments.

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基于宽度自编码网络的单分类集成算法

信号处理 2024年第4期40卷 776-788页

作者：施一帆陈宇昂曾焕强杨楷翔华侨大学工学院福建泉州362021 华南理工大学计算机科学与工程学院广东广州510006 计算机软件新技术国家重点实验室江苏南京210023

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分... 详细信息

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分类算法已经取得了显著进展,然而也存在一些局限性:(1)原始特征空间容易受噪声特征干扰;(2)单模型的单分类算法难以从多个特征空间学习更全面的决策边界;(3)缺少对先前模型的欠拟合样本进行针对性学习。为了解决这些问题,本文提出了基于宽度自编码网络的单分类集成算法(Ensemble One-class Classification Based on BLS-Autoencoder,EOC-BLSAE)。首先,本文设计了一种单分类宽度自编码网络模型(One-class BLS-Autoencoder,OC-BLSAE),它能高效学习原始特征空间到重构特征空间的非线性映射关系,利用重构误差构建决策边界;接着,本文设计了单分类Boosting策略,通过最小化全局重构损失,迭代学习欠拟合样本,从而多角度构建OC-BLSAE模型,并自适应评估模型的可靠性;最终,加权集成多个OC-BLSAE模型,有效提升整体算法准确性和鲁棒性。在实验中,本文在16个不同规模的单分类任务上进行参数实验、对比实验和消融实验,结果表明所提算法参数选择较为灵活,算法各模块能够相互协同,有效提升单分类任务的准确性和鲁棒性,整体性能超过前沿单分类方法。

关键词：单分类异常检测宽度学习系统集成学习