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白喉乌头中二萜生物碱及其拒食活性研究

有机化学 2017年第7期37卷 1839-1843页

作者：陈琳王倩黄帅单连海高峰周先礼西南交通大学生命科学与工程学院成都610031 西南交通大学材料科学与工程学院成都610031 西华师范大学化学化工学院南充637002

从白喉乌头(Aconitum leucostomum Vorosch.)中分离得到13个二萜生物碱,采用HR-ESI-MS,1D NMR和2D NMR等波谱技术确定了它们的结构.其中一个为新的C_(18)二萜生物碱:刺乌宁,其余为已知化合物.同时考察了其中12个化合物对甜菜夜蛾3龄幼... 详细信息

从白喉乌头(Aconitum leucostomum Vorosch.)中分离得到13个二萜生物碱,采用HR-ESI-MS,1D NMR和2D NMR等波谱技术确定了它们的结构.其中一个为新的C_(18)二萜生物碱:刺乌宁,其余为已知化合物.同时考察了其中12个化合物对甜菜夜蛾3龄幼虫的拒食活性,结果表明化合物氨茴酰基牛扁碱和东乌头定的活性较好(EC_(50)<1mg/cm^2),其次是N-acetylsepaconitine,赣乌碱和N-去乙酰高乌甲素(EC_(50)<2 mg/cm^2).

关键词：乌头属白喉乌头二萜生物碱 leucostonine 拒食活性

MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen wang Wei Ming Longfu chen Tianliang Song Moxi Yele Hao Zhang Long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

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无烟煤微生物成气中间代谢产物组成及其转化

煤炭学报 2016年第9期41卷 2305-2311页

作者：陈林勇王保玉邰超关嘉栋赵晗王美林韩作颖山西晋城无烟煤矿业集团有限责任公司煤与煤层气共采国家重点实验室山西晋城048000 河南理工大学资源环境学院河南焦作454000 河南理工大学中原经济区煤层(页岩)气河南省协同创新中心河南焦作454000

研究了煤生物成气过程中中间产物的变化规律与成气过程的相互关系。以10 kg沁水盆地山西寺河矿的无烟煤为底物,以寺河矿区煤层气井口出水为菌源,进行了煤生物成气模拟实验,利用气相色谱-质谱联用对不同成气阶段发酵液中间产物进行了分... 详细信息

研究了煤生物成气过程中中间产物的变化规律与成气过程的相互关系。以10 kg沁水盆地山西寺河矿的无烟煤为底物,以寺河矿区煤层气井口出水为菌源,进行了煤生物成气模拟实验,利用气相色谱-质谱联用对不同成气阶段发酵液中间产物进行了分析。实验发现煤生物成气有2个主要的产气周期,芳香环、杂环化合物和苯衍生物在反应初期转化为VFA等,发生在第1个产气周期;而长链烷烃的生成有2个高峰期,分别对应2个产气周期。根据煤生物成气模拟实验中间代谢产物的实验结果,进一步选取乙酸钠、丙酸钠、丁酸钠、己酸为底物,仍以同一煤层气井口出水为菌源,进行产气实验模拟,结果显示乙酸、丙酸、丁酸可以产气,而己酸则对成气呈现抑制作用。以底物计算甲烷产生效率为丁酸>丙酸≈乙酸,丁酸约为乙酸和丙酸的4倍;而以碳数计算时甲烷产生效率则为丁酸>乙酸>丙酸,丁酸约为乙酸的2倍,说明不同的有机酸产甲烷时可能存在有机酸碳数奇偶性的差异。以上结果表明,VFA和长链烷烃在煤生物成气中发挥着重要的作用,而有关煤生物成气中VFA和长链烷烃的生成和转化以及其对成气的影响尚需进一步研究。

关键词：煤生物成气代谢产物 VFA 长链烷烃

All-optical neuromorphic devices: materials, working mechanism,and applications

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Science China Chemistry 2025年

作者： Song wang Hao chen Hui Huang College of Materials Science and Opto-Electronic Technology Center of Materials Science and Optoelectronics Engineering CAS Center for Excellence in Topological Quantum Computation CAS Key Laboratory of Vacuum Physics University of Chinese Academy of Sciences College of Chemistry and Molecular Engineering Peking University

Traditional von Neumann computing, with physical separation of memory and processing units, cannot satisfy the development of artificial intelligence and cloud computing. Neuromorphic computing, inspired by the human brain, has drawn much ***-optical neuromorphic (AON) devices employ optical signals as information carriers and leverage the neuromorphic functions to implement fast operation speed, low energy consumption, and high bandwidth of neuromorphic computing. Here, we discuss the recent progress in AON devices, including materials, device performance, working mechanisms, and applications. Moreover,the advantages and limitations of AON are presented and discussed. Finally, the perspective of AON devices points out the future research direction of neuromorphic computing.

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Enantioselective β-alkenylation of α,β-unsaturated aldehydes via chiral biphosphine ligand modified dirhodium(II) catalysis

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Science China Chemistry 2025年

作者： Guangli Xu Hongda chen Xiaoming wang State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences School of Chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Dirhodium(II) complexes have achieved great success in organic synthesis,and fine-tuning their catalytic properties with various bridging ligands is well-investigated in carbene ***,combining dirhodium(II) with a sophisticated ligand as a catalyst in other reactions is still extremely challenging,especially for the asymmetric synthesis of valuable chiral ***,we report a dirhodium(II)/(S)-MeO-BIPHEP catalytic system for the challenging asymmetric β-alkenylation of α,β-unsaturated aldehydes,affording the corresponding chiral conjugate addition products in good yields with high enantioselectivities.A couple of drug-derived substrates were also compatible with the protocol,which has been successfully used to prepare biologically relevant pyranochromene *** mechanistic studies suggested that the dirhodium core might remain intact over the catalytic cycle,and the chiral diphosphine ligand plays a key role in this novel reactivity and determining the high enantioselectivities of the asymmetric conjugate addition.

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Altered visceral sensitivity in the irritable bowel syndrome subgroups in rat models

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Altered visceral sensitivity in the irritable bowel syndrome...

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

第二十二届全国中西医结合消化系统疾病学术会议暨消化疾病诊治进展学习班

作者： Zhengyang Li,Yan chen,Meifeng wang,lin lin,Hongjie Zhang~* The Department of digestive disease,the First Affiliated Hospital of Nanjing Medical University, Nanjing,China

BACKGROUND & OBJECTIVE:IBS(irritable bowel syndrome,IBS) in the etiology and pathogenesis is not entirely *** mainly is related to abnormal intestinal motility,abnormal visceral

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Neural Regeneration Research 2025年第3期20卷 740-750页

作者： Yuchen Zhang Yiqing chen cheng Zhuang Jingxuan Qi Robert Chunhua Zhao Jiao wang School of Life Sciences Shanghai UniversityShanghaiChina School of Medicine Shanghai UniversityShanghaiChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic MedicinePeking Union Medical CollegeBeijingChina Center of Excellence in Tissue Engineering Chinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy BeijingChina

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous *** droplet formation begins with the synthesis of neutral lipids in the endoplasmic ***,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous *** addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress ***,lipid droplets exhibit specific functions in neurons and glial *** of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system *** review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and ***,it will explore the association between lipid droplets and neurodegenerative *** the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

关键词： Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease

Growth behavior and electronic regulation of Pt on various Mo-based supports for hydrogen evolution electrocatalysis

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Science China Chemistry 2025年

作者： Lulu chen Yichao Huang Jiajun wang Meihong Liao Zhiyuan Liu Meiqi Liu Hanqing Cai lin wang Lidong Gao Dawei Hu Lianming Zhao Ning Pu Zhuangjun Fan State Key Laboratory of Chemical Safety School of Materials Science and Engineering China University of Petroleum (East China) School of Mechanical and Electronic Engineering Qingdao Binhai University Qingdao Chuangqi New Energy Catalysis Technology Co.Ltd. Sinopec Research Institute of Petroleum Processing Co.Ltd. Institute of Energy Hefei Comprehensive National Science Center

Insight into the growth behavior and electronic regulation of platinum （Pt） on various transition metal supports is paramount in developing high-performing electrocatalysts for hydrogen evolution reactions （HER）.Herein,we studied the influence of molybdenum-based supports （MoX,X=C,N,P,and S） on the growth behavior and electronic regulation of *** found that the formation energy variations between Pt single atom and clusters on MoX supports play a pivotal role in the growth behavior of ***,the electronic regulation of Pt induced by metal-support interaction may reflect the valence changes of Pt in Pt-MoX/*** Pt-MoC/C catalyst with a moderate valence state of Pt exhibits the best HER activity with an overpotential of 12.0 mV at 10 mA cm-2and a mass activity of 27.1 A mgPt-1,12.3 times as high as that of commercial 20 wt% Pt/*** work provides constructive guidance for the design of high-performance HER catalysts.

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Al/U固相界面反应的原位高温X射线衍射研究

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稀有金属材料与工程 2017年第9期46卷 2465-2469页

作者：张延志谢卫华管卫军陈林汪小琳中国工程物理研究院材料研究所四川绵阳621907 表面物理与化学重点实验室四川绵阳621907 中国工程物理研究院四川绵阳621900

采用磁控溅射沉积技术在贫铀上镀铝膜,利用X射线衍射原位研究了铝镀层与贫铀基体的界面反应,分析了界面反应产物随温度和时间的变化规律。实验结果显示,镀膜过程Al/U界面没有化合物形成,而在较高温度下(≥335℃)两相界面会发生反应并形... 详细信息

采用磁控溅射沉积技术在贫铀上镀铝膜,利用X射线衍射原位研究了铝镀层与贫铀基体的界面反应,分析了界面反应产物随温度和时间的变化规律。实验结果显示,镀膜过程Al/U界面没有化合物形成,而在较高温度下(≥335℃)两相界面会发生反应并形成金属间化合物UAl_3相,反应动力学符合形核-生长机制。形成的UAl_3相为疏松的层状结构,且相应的衍射峰强度随温度的升高而逐渐降低,直至消失,文中对该现象的原因进行了分析和讨论。

关键词： Al/U 界面反应金属间化合物 X射线衍射