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First Total Synthesis of an Analogue of (±)-Hypargenin B

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Chinese Chemical Letters 2002年第2期13卷 133-134页

作者： An Pai LI Hui WANG Cheng Lu ZHANG Tong xing WU xin fu pan Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

First total synthesis of (±)-hypargenin B methyl ether 2 was accomplished via a strategy of ACABC, in which CrO3/H2O/NaOAc/HOAc system was utilized for introducing 7-keto group in order to avoid dehydration of benzyl... 详细信息

关键词： Hypargenin B diterpene intramolecular steroselective.

Total Synthesis of (±) Kadsurenin M

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Chinese Chemical Letters 1997年第2期8卷 101-102页

作者： Ming Yi WANG An xin Wu and xin fu pan(Department of Chemistry, State Key Laboratory of Applied Organic Chemistry,Lanzhou Universtiy,Lanzhou 730000)Xiao Jiang HAO Chang Xiang CHEN(Laboratory of Phytochemistry, Kunming Institute of Botany,Academia Sinica Department of Chemistry State Key Lab. of Appl. Organ. Chem. Lanzhou University Lanzhou 730000 China Laboratory of Phytochemistry Kunming Institute of Botany Academia Sinica Kunming 650204 China

Kadsurenin M (7s, 8s- 3, 4, 3'- trimethoxy- 7'- o\o- nor-8', 9'-7. O, 4' - 8, 5'-neolingan)(1), a benzofuranoid neolignan isolated tyom the aerial part of Piper Kadsura (Choisy) Ohwi,was synthesized in 6 steps from vanillin via a key intermediate 3,4- dimethoxycinnamyl (2'-methoxy- 4'- formyl)phenyl ether (7). The overall yield is 15%.

关键词： OCH Kadsurenin M MHz Cl Total Synthesis of

An Efficient and Stereoselective Synthesis of (-)-Massoialactone

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Chinese Chemical Letters 1997年第1期8卷 13-14页

作者： Chi ZHANG Fang Ning ZHANG Xue Chao WANG Yu REN and xin fu pan(Department of Chemistry, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou730000) Department of Chemistry State Key Lab. of Appl. Organ. Chem. Lanzhou University Lanzhou 730000 China

An efficient and stereoselective four step synthesis of (-)-Massoialactone (1) is described. The key step involves deoxygenation of one alpha,beta - unsaturated carbonyl group in compound 5.

关键词： An Efficient and Stereoselective Synthesis of Cl Zhang Massoialactone

Real-Time Intelligent Diagnosis of Co-frequency Vibration Faults in Rotating Machinery Based on Lightweight-Convolutional Neural Networks

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 264-282页

作者： xin pan Xiancheng Zhang Zhinong Jiang Guangfu Bin Beijing Key Laboratory of Health Monitoring and Self-recovery for High-End Mechanical Equipment College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Engine Health Monitoring-Control and Networking(Ministry of Education) College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Mechanical Engineering Hunan University of Science and TechnologyXiangtan 411201China

The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the *** engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively ***,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault *** critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation *** on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is ***,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault *** is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance.

关键词： Co-frequency vibration Real-time diagnosis LW-CNN Data augmentation

Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei Li xin pan Dehong Ge Jinji Gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty *** accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite *** can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment *** composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed *** fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery *** experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

THE REARRANGEMENT OF 1,7β-DIMETHYL-7α-HYDROXY-8aα-CARBOXYMETHYL-9β-CARBOMETHOXY-4bα, 5, 6, 7, 8, 8a-HEXAttYDROFLUORENE LACTONE INDUCED BY DIBAL-H

维普期刊数据库评论

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Chinese Chemical Letters 1991年第10期2卷 761-762页

作者： Hun Ping HU xin WANG and xin fu pan State Key Laboratory. of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000

1,7β- Dimethyl-7α- hydroxy-8aα-carboxymethyl-9β-carbomethoxy-4bα, 5, 6, 7, 8, 8α-hexahydrofluorene lactone(2) is converted to 8, 12-epoxyallogibberic acid methyl ester(4) by the action of diisobutyl aluminum hyd... 详细信息

关键词： CARBOMETHOXY-4b CARBOXYMETHYL-9 HYDROXY-8a DIMETHYL-7 THE REARRANGEMENT OF 1,7

Evaluation of 3D crustal seismic velocity models in southwest China:Model performance,limitation,and prospects

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Science China Earth Sciences 2024年第2期67卷 604-619页

作者： xin WANG Ling CHEN Qi-fu CHEN Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest China is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2021 Yunnan Yangbi MS_(6.4) earthquake sequence and the 2022 Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest China Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental China Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(pancies in higher frequencies(0.05–0.3 Hz)and the performance of the 3D velocity models varies from region to region,suggesting that smaller scale heterogeneities are not well *** shallow velocity structures(full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest China Seismic tomography models Shallow Structures Waveform simulation Model evaluation

Total Synthesis of (±)-Celaphanol A

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Chinese Chemical Letters 2002年第9期13卷 830-831页

作者： Ping Yan BIE Cheng Lu ZHANG Xuan Jia PENG xin fu pan Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

The first total synthesis of (?-Celaphanol A was accomplished starting from cyclocitral and 3,4-dimethoxy benzyl chloride via a six-step process, in which the intramolecular cyclization of ketone 4 with BF3稥t2O affor... 详细信息

关键词： (±)-celaphanol A Diterpene Total synthesis

FACILE SYNTHESES OF PLUMBAGIC ACID

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Chinese Chemical Letters 1992年第5期3卷 333-334页

作者： Xue Chao WANG xin fu pan xin Mei GE Gong Cheng ZHANGState Key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou,730000

Plumbagic acid[β-(2,3-dihydroxybenzoyl)butyric acid](1),has been synthesized from commcrcially available catechol by two facile routes with overall yields of 18.6% and 53.5%,rcspectively.

关键词： THF FACILE SYNTHESES OF PLUMBAGIC ACID