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Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-fei Guo Ze-Long liang Yue-E Jiao hang Xu Bin Zhao Key Laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,etc.Major studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali co-catalysts.Therefore,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction conditions.Herein,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,respectively.Cu NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild conditions.The corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale experiments.Additionally,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air conditions.Importantly,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@1-3.Mechanism investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal centers.More importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

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Applanoids A—E as the First Examples of C-15/C-20 Michael Adducts in Ganoderma Triterpenoids and Their PXR Agonistic Activity

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Chinese Journal of Chemistry 2022年第22期40卷 2633-2641页

作者： Hai-Guo Su Hang-Fei liang Gui-Lin Hu Lin Zhou Xing-Rong Peng Hui-Chang Bi Ming-Hua Qiu Guangdong Provincial Key Laboratory of New Drug Design and Evaluation School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhouGuangdong510006China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China NMPA Key Laboratory for Research and Evaluation of Drug Metabolism&Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China

Ganoderma triterpenoids(GTs),a class of major active constituents of Ganoderma fungi,possess diverse structures and remarkable activities.In the present study,nine new GTs,namely applanoids A—I(1—9),were isolated from the medicinal fungus of Ganoderma applanatum.Their structures including absolute configurations were established by comprehensive spectroscopic analyses and ECD calculation.Applanoids A—E(1—5)represent the first example of GTs with 6/6/5/6/5 pentacyclic system and the formation of the ether ring between C-15 and C-20 involves Michael addition reaction.Furthermore,compounds 1—8 were evaluated for their human pregnane X receptor(hPXR)agonistic activity using dual-luciferase reporter gene assay,and the results showed that compounds 1,2 and 4 can dose-dependently activate hPXR.This investigation further illustrated the structural diversity of GTs and provided new insights for searching PXR agonists from GTs.

关键词： Ganoderma applanatum Lanostane triterpenoids Michael adducts Structure elucidation Pregnane X receptor

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Experiments on unconfined compressive strength of lignin modified silt in Yellow river flood area under freezing-thawing cycles

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Yantu Lixue/Rock and Soil Mechanics 2020年 41卷 271-276页

作者： Zhang, Jian-Wei Kang, fei-Xiang Bian, Han-liang Yu, hang School of Civil Engineering and Architecture Henan University Kaifeng 475004 China Henan Provincial Research Center of Engineering on Intelligent Construction of Rail Transit Kaifeng 475004 China Kaifeng Technology Research Center of Engineering on Soil Modification and Restoration Kaifeng 475004 China

The strength of silty soil in the Yellow River flood area is low caused by poor grain composition and other features. In order to improve the strength of silty soil in the Yellow River flood area, the lignin is used to reinforce the silty soil. The relationship between the unconfined compression strength of silty soil and the mixing amount of lignin, the number of freezing and thawing cycles and curing period are analyzed. The unconfined compression strength test and freezing and thawing test are carried out on soil reinforced by lignin with a certain moisture content. The experimental results show that the lignin can improve the unconfined compression strength of silty soil. Under a certain number of freezing and thawing cycles, the unconfined compression strength of lignin-improved soil increases at first and then decreases with the increase of lignin proportion. The unconfined compression strength of silty soil is greatest when the mixing amount of lignin is 5%. When the amount of lignin is constant, the unconfined compression strength of reinforced soil increases with curing period. When the mixing amount of lignin is 5%, the strength of lignin-improved soil at 28 days is 1.77 times stronger than at 7 days. As the number of freezing and thawing cycles increases, the unconfined compression strength of lignin-improved soil decreases. Under the same number of freeze-thaw cycles, the reduction of unconfined compression strength in lignin-improved soil is less than that of plain soil, demonstrating that the durability of lignin-improved soil is better than that of plain soil. Based on SEM analysis, it can be clearly shown that lignin can effectively fill the pores between soil particles to improve the strength of soil. However, it does not gradually increase with the increase of mixture amount, and an optimal amount of admixture exists. © 2020, Science Press. All right reserved.

关键词： Lignin

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Superior high-temperature wear resistance of an Ir-Ta-Ni-Nb bulk metallic glass

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Journal of Materials Science & Technology 2023年第27期158卷 121-132页

作者： fei Sun Shengtao Deng Jianan Fu Jiahua Zhu Dandan liang Pengfei Wang hang Zhao Feng Gong Jiang Ma Yanhui Liu Jun Shen Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Cross-scale Manufacturing Mechanics Southern University of Science and Technology Shenzhen 518055China Shanghai Engineering Research Center of Physical Vapor Deposition(PVD)Superhard Coating and Equipment Shanghai Institute of TechnologyShanghai 201418China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Wear resistance is a critical consideration in engineering applications.In this study,we demonstrated an Ir-Ta-Ni-Nb bulk metallic glass(BMG)with outstanding high-temperature wear resistance and revealed its promising applications in extreme environments.The wear behavior and mechanism were systemati-cally investigated from room temperature(RT)to 750℃.The results show that the wear rate increases from∼2.65×10^(-6)mm^(3)N^(-1)m^(-1)to∼10.56×10^(-6)mm^(3)N^(-1)m^(-1)in the temperature span RT to 400℃,following abrasive wear and flash temperature-induced oxidative wear during the friction.However,at the higher temperature of 600℃,further heating due to frictional heat leads to a softening of the wear surface,resulting in a maximum wear rate of∼20.99×10^(-6)mm^(3)N^(-1)m^(-1)under softness-driven abrasive wear as well as oxidative wear.Interestingly,the wear resistance at an even higher temperature of 750℃shows a paradoxical improvement of∼7.08×10^(-6)mm^(3)N^(-1)m^(-1),which is attributed to the formation of an oxide layer with a thickness of several microns,avoiding violent wear of BMG.The re-sults demonstrate the unreported outstanding high-temperature wear resistance of the Ir-Ta-Ni-Nb BMG,especially its excellent capability to resist wear at 750℃,leading to the promising applications of BMG in the fields of aerospace,metallurgy,and nuclear industries.

关键词： High-temperature alloy Superior wear resistance Wear mechanisms Bulk metallic glass

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Corrosion behaviours of the dental magnetic keeper complexes made by different alloys and methods

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International Journal of Oral Science 2016年第3期8卷 155-163页

作者： Min-Ke Wu Ning Song fei Liu liang Kou Xiao-Wen Lu Min Wang hang Wang Jie-fei Shen State Key Laboratory of Oral Diseases West China Hospital of Stomatology Sichuan University Chengdu China Ningbo Dental Hospital Ningbo China

The keeper and cast dowel-coping, as a primary component for a magnetic attachment, is easily subjected to corrosion in a wet environment, such as the oral cavity, which contains electrolyte-rich saliva, complex microflora and chewing behaviour and so on. The objective of this in vitro study was to examine the corrosion resistance of a dowel and coping-keeper complex fabricated by finish keeper and three alloys （cobalt-chromium, CoCr; silver-palladium-gold, PdAu; gold-platinum, AuPt） using a laser- welding process and a casting technique. The surface morphology characteristics and microstructures of the samples were examined by means of metallographic microscope and scanning electron microscope （SEM）. Energy-dispersive spectroscopy （EDS） with SEM provided elements analysis information for the test samples after 10% oxalic acid solution etching test. Tafel polarization curve recordings demonstrated parameter values indicating corrosion of the samples when subjected to electrochemical testing. This study has suggested that massive oxides are attached to the surface of the CoCr-keeper complex but not to the AuPt-keeper complex. Only the keeper area of cast CoCr-keeper complex displayed obvious intergranular corrosion and changes in the Fe and Co elements, Both cast and laser-welded AuPt-keeper complexes had the highest free corrosion potential, followed by the PdAu-keeper complex. We concluded that although the corrosion resistance of the CoCr-keeper complex was worst, the keeper surface passive film was actually preserved to its maximum extent. The laser-welded CoCr- and PdAu-keeper complexes possessed superior corrosion resistance as compared with their cast specimens, but no significant difference was found between the cast and laser-welded AuPt-keeper complexes. The Fe-poor and Cr-rich band, appearing on the edge of the keeper when casting, has been proven to be a corrosion-prone area.

关键词： cobalt-chromium alloy corrosion behaviour dental magnets gold-platinum alloy magnetic attachment silver-palladium-gold alloy

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Chlorogenic acid alters the voltage-gated potassium channel currents of trigeminal ganglion neurons

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International Journal of Oral Science 2014年第4期6卷 233-240页

作者： Yu-Jiao Zhang Xiao-Wen Lu Ning Song liang Kou Min-Ke Wu fei Liu hang Wang Jie-fei Shen State Key Laboratory of Oral Diseases West China Hospital of Stomatology Sichuan University Ningbo Dental Hospital

Chlorogenic acid（5-caffeoylquinic acid, CGA） is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to its notable biological functions against cardiovascular diseases, type-2 diabetes and inflammatory conditions, CGA was recently hypothesized to be an alternative for the treatment of neurological diseases such as Alzheimer＇s disease and neuropathic pain disorders. However, its mechanism of action is unclear.Voltage-gated potassium channel（Kv） is a crucial factor in the electro-physiological processes of sensory neurons. Kv has also been identified as a potential therapeutic target for inflammation and neuropathic pain disorders. In this study, we analysed the effects of CGA on the two main subtypes of Kv in trigeminal ganglion neurons, namely, the IK,Aand IK,Vchannels. Trigeminal ganglion（TRG）neurons were acutely disassociated from the rat TRG, and two different doses of CGA（0.2 and 1 mmol·L21） were applied to the cells.Whole-cell patch-clamp recordings were performed to observe alterations in the activation and inactivation properties of the IK,Aand IK,Vchannels. The results demonstrated that 0.2 mmol·L21CGA decreased the peak current density of IK,A. Both 0.2 mmol·L21and1 mmol·L21CGA also caused a significant reduction in the activation and inactivation thresholds of IK,Aand IK,V. CGA exhibited a strong effect on the activation and inactivation velocities of IK,Aand IK,V. These findings provide novel evidence explaining the biological effects of CGA, especially regarding its neurological effects.

关键词： chlorogenic acid trigeminal ganglion neuron voltage-gated potassium channel whole-cell patch clamp

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基于Bi-LSTM的非等时距路基工后沉降滚动预测

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浙江大学学报（工学版） 2022年第4期56卷 683-691页

作者：陈伟航罗强王腾飞蒋良潍张良西南交通大学土木工程学院四川成都610031 高速铁路线路工程教育部重点实验室四川成都610031

为了实现路基工后沉降的早期、精准预测,提出基于双向长短期记忆网络(Bi-LSTM)的路基沉降预测技术.采用Akima法将观测数据内插为适应时序分析法的等时距序列,提取“填土高度-时间-地基沉降”曲线中的6个影响因素作为变量训练Bi-LSTM模型... 详细信息

为了实现路基工后沉降的早期、精准预测,提出基于双向长短期记忆网络(Bi-LSTM)的路基沉降预测技术.采用Akima法将观测数据内插为适应时序分析法的等时距序列,提取“填土高度-时间-地基沉降”曲线中的6个影响因素作为变量训练Bi-LSTM模型,结合滚动迭代方法实现沉降预测的后延更新.研究表明,利用深度学习技术可以有效地利用路基施工期信息,增加训练样本量,提升沉降早期预测的可靠性.Bi-LSTM模型对观测信息进行双向特征提取,同等样本量下的预测效果更精确.依托6个中等压缩性土地基和1个复合地基监测断面信息,仅利用路堤填筑期及工后3个月数据,沉降预测的均方根误差(RMSE)和平均绝对百分误差(MAPE)平均值可以控制为1.19 mm、1.04%.

关键词：双向长短期记忆网络(Bi-LSTM) 路基工后沉降非等时距序列滚动预测施工填筑信息

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Infection and pathogenesis of the Delta variant of SARS-CoV-2 in Rhesus macaque

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Virologica Sinica 2022年第2期37卷 299-302页

作者： Ge Gao Xue Hu Yiwu Zhou Juhong Rao Xiaoyu Zhang Yun Peng Jiaxuan Zhao Yanfeng Yao Kunpeng Liu Mengying liang hang Liu fei Deng Han Xia Chao Shan Zhiming Yuan Center for Biosafety Mega-Science Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China Department of Forensic Medicine Tongji Medical College of Huazhong University of Science and TechnologyWuhan430030China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China

Dear Editor,COVID-19 caused by SARS-Co V-2,is still a big threat to human populations around the world.As of Jan 2022,over 292 million cases were reported worldwide with more than 5.4 million deaths.After it was first reported in China in December 2019,the virus kept circulating and evolving and several variants with different transmissibility emerged in different countries and regions(WHO,2021a).

关键词： Delta milli emerged

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Fast extraction of winter wheat planting area in Huang-Huai-Hai Plain using high-resolution satellite imagery on a cloud computing platform

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International Journal of Agricultural and Biological Engineering 2022年第1期15卷 241-250页

作者： Dongyan Zhang Mengru Zhang Fenfang Lin Zhenggao Pan fei Jiang liang He hang Yang Ning Jin National Engineering Research Center for Agro-Ecological Big Data Analysis&Application Anhui UniversityHefei 230601China Key Laboratory of Geospatial Technology for Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475004HenanChina School of Informatics and Engineering Suzhou UniversitySuzhou 234000AnhuiChina National Meteorological Center Beijing 100081China Aerospace Information Research Institute Chinese Academy of ScienceBeijing 100101China

To extract regional winter wheat planting area using higher-resolution satellite imagery still faces many challenges due to large data size and long processing time in traditional remote sensing classification.Google Earth Engine(GEE),a cloud computing analysis platform based on global geospatial analysis,provides a new opportunity for rapid analysis of remote sensing data.In this study,high-quality Landsat-8 imagery was used to extract the winter wheat planting area from the Huang-Huai-Hai Plain in China.The random forest algorithm was used to identify and map the winter wheat sown in 2019 and harvested in 2020,and Sentinel-2 imagery was used to verify the results.The spectral indices,texture,and terrain features of the image were derived,and their contribution to the classification accuracy of winter wheat was evaluated by scoring.Then the top nine features were selected to form an optimal feature subset.Comparing the set of thirty-four features and the optimized feature subset as the input variables of the random forest classifier,the results show that the accuracy difference between the two feature classification schemes is small,but the classification effect of all feature sets is slightly better than the optimal feature subset.The overall classification accuracy of sample plots verification was 86%-95%,the Kappa coefficient was between 0.7 and 0.85,and the percentage error of the total area was 5.42%.The research demonstrates a reliable method for mapping a wide range of winter wheat planting area,and provides a good prospect for exploring the precise mapping of other crops,which is of great significance to crop monitoring and agricultural development.

关键词： Google Earth Engine regional scale winter wheat rapid mapping

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面向B5G/6G的GFDM信号高精度测距与定位研究

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电子学报 2022年第4期50卷 849-859页

作者：苏林林陈亮陈菲菲周鑫焦振航刘钊良武汉大学测绘遥感信息工程国家重点实验室湖北武汉430079

广义频分复用(Generalized Frequency Division Multiplexing,GFDM)技术是在正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术基础上发展而来的一种新的多载波调制技术,其特点是子载波非正交以及具有灵活的时频资源配置.GFDM作为目前研究的主流波形,有望成为B5G(Beyond Fifth-Generation)或者6G(Sixth-Generation)时代移动通信技术的新的波形设计.本文提出了基于GFDM信号的高精度载波测距方法,其主要包括GFDM信号粗同步、导频检测、多径提取、首径获取、延迟跟踪和载波相位测距等步骤.在此基础上,利用GFDM信号测距信息进行了室内定位性能评估.在典型室内会议场景下搭建了实测平台并对上述方法进行了验证.测试结果表明,通过所提方法,利用GFDM信号测距精度达到1.1 m(95%),定位精度优于2 m,相比于相同带宽的OFDM信号测距性能提高了21%.本文研究将为下一代移动通信室内定位技术提供有益参考.

关键词：无线室内定位广义频分复用压缩感知载波相位测距到达时间差

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