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A new bidesmoside triterpenoid saponin from Stauntonia chinensis

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Chinese Chemical Letters 2009年第7期20卷 833-835页

作者： Dong Wang Guo Ping Zhou Yi Sheng Yang Ya Lun Su teng fei ji jiangxi Provical Institute For Drug And Food Contral Nanchang 330029 China Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China

A new bidesmoside triterpenoid saponin, named stauntoside C1 （1） has been isolated from Stauntonia chinensis. Its structure was established by means of spectral and chemical methods. C 2009 Guo Ping Zhou. Published ... 详细信息

关键词： Bidesmoside triterpenoid saponins Stauntonia chinensis Stauntoside C1

A novel phenylpropanoid glycoside from Callicarpa kwangtungensis Chun

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Chinese Chemical Letters 2009年第7期20卷 827-829页

作者： Er Lei Xie Guo Ping Zhou teng fei ji Jun Wu Gui Ping Yuan jiangxi Provical Institute for Drug and Food Control Nanchang 330029 China Key Laboratory of Bioactive substances and Resources Utilization of Chinese Herbal Medicine Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

A novel phenylpropanoid glycoside, Callicarposide A has been isolated from the aerial parts of Callicarpa kwangtungensis Chun. The chemical structure is elucidated on the basis of spectral analysis. C 2009 teng fei ji... 详细信息

关键词： Callicarpa kwangtungensis Chun Phenylpropanoid glycoside Callicarposide A

Lipase-catalyzed Knoevenagel condensation between α,β-unsaturated aldehydes and active methylene compounds

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Chinese Chemical Letters 2014年第5期25卷 802-804页

作者： Zhi Wang Chun-Yu Wang Hao-Ran Wang Hong Zhang Ya-Lun Su teng-fei ji Lei Wang Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education College of Life ScienceJilin University State Key Laboratory of Supramolecular Structure and Materials Jilin University State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical College

A simple and efficient Knoevenagel condensation between a b-unsaturated aldehydes and active methylene compounds is ***,this condensation can be catalyzed by PPL（lipase from porcine pancreas） with satisfied yields（... 详细信息

关键词： Lipase Knoevenagel condensation a b-Unsaturated aldehyde Active methylene compound

Hyperterpenoids A and B:Two pairs of unprecedented 6/6/4/6/6 polycyclic cyclobutane meroterpenoids with potent neuroprotective and anti-inflammatory activities from Hypericum beanii

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Chinese Chemical Letters 2021年第7期32卷 2338-2341页

作者： Bo Zhen Xinyue Suo Jun Dang Huilan Yue Yanduo Tao jia-jia Wang Li Li Ming-Bao Lin Qi Hou Wei-Ping Wang Xiao-Liang Wang jian-Dong jiang teng-fei ji State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Key Laboratory of Tibetan Medicine Research Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China

Hyperterpenoid A(1)and B(2),two pairs of enantiomers,with an unprecedented 6/6/4/6/6 polycyclic skeleton,along with one known compoud hypermonone A(3)were isolated from Hypericum *** racemate(±)-1 and(±)-2 were successfully separated into the two optically pure enantiomers(ee>99%)using a preparative HPLC *** absolute configurations were elucidated by extensive spectroscopic analyses and single-crystal X-ray diffraction *** related plausible biogenetic pathways were pre *** 1-3 showed significant neuroprotective activity and potential antiinflammatory *** result that(+)-2 and(-)-2 presented different anti-inflammatory properties,may lead us to new discovery of structure activity relationship between racemates,enantiomers,and diastereomers,as well as further research regarding the binding of drugs to target proteins.

关键词： Hypericum beanii Meroterpenoids (±)-Hyperterpenoid A and B Anti-inflammatory activity Neuroprotective activity

Application of New Empirical Models Based on Mathematical Statistics in the Through-Flow Analysis

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Journal of Thermal Science 2021年第6期30卷 2087-2098页

作者： fei teng ji Lucheng School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The through-flow analysis is an important part in the compressor design *** this part,lots of empirical models are used to predict the compressor aerodynamic *** models are all based on the early experimental results of low-load and low-speed compressors;so,they may not be suitable for modern compressor performance *** this study,several empirical models were reviewed,and two new models to estimate the minimum blade profile loss and minimum-loss deviation angle were established using mathematical ***,the original models with poor accuracy were replaced by these two models in through-flow ***,three compressors(Rotor 67,Stage 35,and a 4-stage repeating stage)were simulated using both the original and new *** final results show that the new models have better accuracy in estimating the performance parameters than the original *** indicates that it is feasible to use mathematical statistical methods to establish the empirical models,and this method provides an idea for the improvement of other empirical models in through-flow program.

关键词： through-flow analysis empirical models blade loss deviation regression analysis

Scattering for 3D Cubic Focusing NLS on the Domain Outside a Convex Obstacle Revisited

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Acta Mathematica Sinica,English Series 2022年第6期38卷 1054-1068页

作者： Cheng Bin XU teng fei ZHAO ji Qiang ZHENG The Graduate School of China Academy of Engineering Physics Beijing 100088P.R.China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083P.R.China Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088P.R.China

In this article,we consider the focusing cubic nonlinear Schr?dinger equation(NLS)in the exterior domain outside of a convex obstacle in R3with Dirichlet boundary *** revisit the scattering result below ground state in Killip-Visan-Zhang[The focusing cubic NLS on exterior domains in three ***,1,146-180(2016)]by utilizing the method of Dodson and Murphy[A new proof of scattering below the ground state for the 3d radial focusing cubic ***.,145,4859-4867(2017)]and the dispersive estimate in Ivanovici and Lebeau[Dispersion for the wave and the Schr?dinger equations outside strictly convex obstacles and ***.,355,774-779(2017)],which avoids using the concentration *** conquer the difficulty of the boundary in the focusing case by establishing a local smoothing effect of the *** on this effect and the interaction Morawetz estimates,we prove that the solution decays at a large time interval,which meets the scattering criterion.

关键词： Schrodinger equation exterior domain global well-posedness scattering criterion

Terahertz polarization conversion and sensing with double-layer chiral metasurface

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Chinese Physics B 2020年第7期29卷 164-171页

作者： Zi-Yang Zhang fei Fan teng-fei Li Yun-Yun ji Sheng-jiang Chang Institute of Modern Optics Nankai UniversityTianjin 300350China Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Tianjin 300350China

The terahertz(THz)resonance,chirality,and polarization conversion properties of a double-layer chiral metasurface have been experimentally investigated by THz time domain spectroscopy system and polarization detection *** special symmetric geometry of each unit cell with its adjacent cells makes a strong chiral electromagnetic response in this metasurface,which leads to a strong polarization conversion ***,compared with the traditional THz transmission resonance sensing for film thickness,the polarization sensing characterized by polarization elliptical angle(PEA)and polarization rotation angle(PRA)shows a better Q factor and figure of merit(FoM).The results show that the Q factors of the PEA and PRA reach 43.8 and 49.1 when the interval film is 20µm,while the Q factor of THz resonance sensing is only *** these PEA and PRA can play a complementary role to obtain a double-parameter sensing method with a higher FoM,over 4 times than that of resonance *** chiral metasurface and its polarization sensing method provide new ideas for the development of high-efficiency THz polarization manipulation,and open a window to the high sensitive sensing by using THz polarization spectroscopy.

关键词： terahertz chiral metasurface polarization conversion sensing

Multi-model comparison of CO2 emissions peaking in China:Lessons from CEMF01 study

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Advances in Climate Change Research 2018年第1期9卷 1-15页

作者： Oleg LUGOVOY FENG Xiang-Zhao GAO ji LI ji-Feng LIU Qiang teng fei ZOU Le-Le Environmental Defense Fund Washington DC 20009USA Policy Research Center for Environment and Economy Ministry of Environmental ProtectionBeijing 100029China Environmental Defense Fund Beijing 100007China Policy Simulation Laboratory State Information CenterBeijing 100045China National Center for Climate Change Strategy and International Cooperation Beijing 100038China Institutes of Energy Environmentand EconomyTsinghua UniversityBeijing 100084China Institute of Policy and Management Chinese Academy of SciencesBeijing 100190China

The paper summarizes results of the China Energy Modeling Forum's(CEMF)first *** emissions peaking scenarios,consistent with China's Paris commitment,have been simulated with seven national and industry-level energy models and *** CO2 emission trends in the considered scenarios peak from 2015 to 2030 at the level of 9e11 ***-level analysis suggests that total emissions pathways before 2030 will be determined mainly by dynamics of emissions in the electric power industry and transportation *** sectors will experience significant increase in demand,but have low-carbon alternative options for *** on a side-by-side comparison of modeling input and results,conclusions have been drawn regarding the sources of emissions projections differences,which include data,views on economic perspectives,or models'structure and theoretical *** suggestions have been made regarding energy models'development priorities for further research.

关键词： Carbon emissions projections Climate change CO2 emissions peak China’s Paris commitment Top-Down energy models Bottom-Up energy models Multi model comparative study China Energy Modeling Forum(CEMF)

Relation Classification via Sequence Features and Bi-Directional LSTMs

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Wuhan University Journal of Natural Sciences 2017年第6期22卷 489-497页

作者： REN Yuanfang teng Chong LI fei CHEN Bo ji Donghong School of Computer Wuhan University Wuhan 430072Hubei China

Structure features need complicated pre-processing, and are probably domain-dependent. To reduce time cost of pre-processing, we propose a novel neural network architecture which is a bi-directional long-short-term-memory recurrent-neural-network（Bi-LSTM-RNN） model based on low-cost sequence features such as words and part-of-speech（POS） tags, to classify the relation of two entities. First, this model performs bi-directional recurrent computation along the tokens of sentences. Then, the sequence is divided into five parts and standard pooling functions are applied over the token representations of each part. Finally, the token representations are concatenated and fed into a softmax layer for relation classification. We evaluate our model on two standard benchmark datasets in different domains, namely Sem Eval-2010 Task 8 and Bio NLP-ST 2016 Task BB3. In Sem Eval-2010 Task 8, the performance of our model matches those of the state-of-the-art models, achieving 83.0% in F1. In Bio NLP-ST 2016 Task BB3, our model obtains F1 51.3% which is comparable with that of the best system. Moreover, we find that the context between two target entities plays an important role in relation classification and it can be a replacement of the shortest dependency path.

关键词： Bi-LSTM-RNN relation classification sequence features structure features