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Chemical constituents from the aerial parts of Euphorbia sikkimensis and their bioactivities

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Natural Products and Bioprospecting 2013年第3期3卷 112-116页

作者： Da-Song YANG wei-bing peng Zi-Lei LI Xue WANG Jian-Guo wei Ke-Chun LIU Yong-Ping YANG Xiao-Li LI Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Plant Germplasm and Genomics Center the Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China Institute of Tibetan Plateau Research at Kunming Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Biology Institute of Shandong Academy of Sciences Jinan 250014China

Phytochemical investigation of the aerial parts of Euphorbia sikkimensis led to the isolation of one new diterpenoids,named sikkimenoid E(1),together with thirteen other known compounds(2-14).Their structures were established by means of spectroscopic *** 2 was identified to be a trinortriterpenoid,and derived for the first time from a natural *** this paper we reveal for the first time its comprehensive spectral data and NMR spectral *** 4 showed anti-angiogenic activity with an IC_(50) value of 5.66μM in a zebrafish model,and compounds 5 and 6 exhibited cytotoxicity toward A549 cell line with IC_(50) values of 12.12 and 6.45μM,respectively.

关键词： Euphorbia sikkimensis ingenol trinortriterpenoid tocopherol derivatives bioactivities

Output Rate of Atomic Four-Wave Mixing in Two-Component Bose-Einstein Condensate

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Communications in Theoretical Physics 2004年第5期41卷 695-698页

作者： LI Jia-Hua~1 LI wei-bing~1 peng Ju-Cun~2 1 Department of Physics,Huazhong University of Science and Technology,Wuhan 430074,China2 Department of Physics,Xiaogan Normal University,Xiaogan 432100,China Department of Physics Xiaogan Normal University Xiaogan 432100 China

In this letter,following the proposal of Heurich et al.[***.A63(2001)033605],we analyze anddiscuss output rate of atomic four-wave mixing in the two-component Bose-Einstein condensate under the condition ofthe steady *** results show that the magnitude of the signal beam increases with the increase of the intensityof the probe beam,up to a saturated value,then it decreases as the probe beam *** influence of theinteraction range on the signal beam is also *** particular,it is worth while pointing out that in contrast tothe previous solutions,our obtained analytical solutions are of very simple and explicit forms,which open the door forfurther investigating the related physical mechanisms.

关键词： atomic four-wave mixing steady state Bose-Einstein condensate

Research on Stock Price Prediction Method Based on the GAN-LSTM-Attention Model

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Computers, Materials & Continua 2025年第1期82卷 609-625页

作者： peng Li Yanrui wei Lili Yin College of Computer Science and Technology Harbin University of Science and TechnologyHarbin150006China

Stock price prediction is a typical complex time series prediction problem characterized by dynamics,nonlinearity,and *** paper introduces a generative adversarial network model that incorporates an attention mechanism(GAN-LSTM-Attention)to improve the accuracy of stock price ***,the generator of this model combines the Long and Short-Term Memory Network(LSTM),the Attention Mechanism and,the Fully-Connected Layer,focusing on generating the predicted stock *** discriminator combines the Convolutional Neural Network(CNN)and the Fully-Connected Layer to discriminate between real stock prices and generated stock ***,to evaluate the practical application ability and generalization ability of the GAN-LSTM-Attention model,four representative stocks in the United States of America(USA)stock market,namely,Standard&Poor’s 500 Index stock,Apple Incorporatedstock,AdvancedMicroDevices Incorporatedstock,and Google Incorporated stock were selected for prediction experiments,and the prediction performance was comprehensively evaluated by using the three evaluation metrics,namely,mean absolute error(MAE),root mean square error(RMSE),and coefficient of determination(R2).Finally,the specific effects of the attention mechanism,convolutional layer,and fully-connected layer on the prediction performance of the model are systematically analyzed through ablation *** results of experiment show that the GAN-LSTM-Attention model exhibits excellent performance and robustness in stock price prediction.

关键词： Stock price prediction generative adversarial network attention mechanism time-series prediction

Image Series Segmentation and Improved MC Algorithm

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Journal of Shanghai Jiaotong university(Science) 2008年第1期13卷 102-106页

作者：万卫兵施鹏飞 Institute of Image Processing and Pattern Recognition Shanghai Jiaotong University

A semiautomatic segmentation method based on active contour is proposed for computed tomography (CT) image series. First, to get initial contour, one image slice was segmented exactly by C-V method based on Mumford-Shah model. Next, the computer will segment the nearby slice automatically using the snake model one by one. During segmenting of image slices, former slice boundary, as next slice initial contour, may cross over next slice real boundary and never return to right position. To avoid contour skipping over, the distance variance between two slices is evaluated by an threshold, which decides whether to initiate again. Moreover, a new improved marching cubes (MC) algorithm based on 2D images series segmentation boundary is given for 3D image reconstruction. Compared with the standard method, the proposed algorithm reduces detecting time and needs less storing memory. The effectiveness and capabilities of the algorithm were illustrated by experimental results.

关键词： image series active contour image segmentation isosuface marching cubes

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Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao peng Yuefeng Song Ihar Razanau Juanxiu Xiao wei Xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

Crystallization Modulation and Holistic Passivation Enables Efficient Two‑Terminal Perovskite/CuIn(Ga)Se_(2)Tandem Solar Cells

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Nano-Micro Letters 2025年第1期17卷 205-215页

作者： Cong Geng Kuanxiang Zhang Changhua Wang Chung Hsien Wu Jiwen Jiang Fei Long Liyuan Han Qifeng Han Yi‑bing Cheng Yong peng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People’s Republic of China Triumph Photovoltaic Materials Co. Ltd.No.1001 Yannan AvenueHigh‑Tech Development DistrictBengbuAnhui 233000People’s Republic of China College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004People’s Republic of China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)***,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device *** this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK *** addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain ***,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing *** a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our *** validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.

关键词： PVK/CIGS TSCs Irregular rough surfaces Modulating the growth PVK/C60 interface recombination

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Crystal Structure and Magnetic Property of a 3D 3d-4f Heterometallic Coordination Polymers

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Crystal Structure and Magnetic Property of a 3D 3d-4f Hetero...

Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

中国化学会第六届全国结构化学学术会议

作者： Yan-Min bing and wei Shi~*,peng Cheng~* Department of Chemistry,Nankai University,Tianjin 300071,P.R.China.

The magnetic properties of 3d-4f coordination compounds are of great interest in the field of molecular magnetism[1,2].In this contribution,a novel 3d-4f heterometallic polymeric coordination compound {[DyCuL(μ-OH)(μ-O)(μ-O)]·2HO}(1) has been synthesized and characterized by single crystal X-ray diffraction.1 has a DyO center which is constituted of six Dy through eightμ-O bridged and oneμ-O to form an unusual octahedra(Fig.1).Dy ion is eight-coordinated by fourμ-OH,three oxygen

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： LIU wei JIAO Jinxu LUO Dusha ZHOU Junjie SHI Lifen WANG weiwei LI Changqing WANG peng XIONG Dehua LI Hong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing

UHPLC-QTOF-MS^E与UHPLC-MS/MS分析麻黄生物碱在血脑屏障间的移行及脑区分布特征

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药学学报 2017年第9期52卷 1437-1443页

作者：彭秘苏丹李晗芸冯冰薇徐鹏飞宋永贵江西中医药大学江西南昌330006

利用超高效液相色谱-质谱(UHPLC-MS)联用技术,建立麻黄生物碱同分异构体的UHPLC分离方法,定性分析麻黄生物碱移行入血与入脑成分,定量测定并比较麻黄生物碱在血脑屏障间的分布情况,并获得在大鼠中枢神经系统不同部位(大脑皮层、小脑、... 详细信息

利用超高效液相色谱-质谱(UHPLC-MS)联用技术,建立麻黄生物碱同分异构体的UHPLC分离方法,定性分析麻黄生物碱移行入血与入脑成分,定量测定并比较麻黄生物碱在血脑屏障间的分布情况,并获得在大鼠中枢神经系统不同部位(大脑皮层、小脑、海马、纹状体、延髓和下丘脑)的分布特征与差异。研究表明,麻黄碱、伪麻黄碱、去甲基麻黄碱、去甲基伪麻黄碱和甲基麻黄碱(甲基伪麻黄碱)经胃肠吸收后可通过血脑屏障快速入脑,定量测定结果显示,麻黄生物碱主要分布在大脑皮层、海马区域,其次为下丘脑、纹状体与小脑,最少分布在延髓部位。不同生物碱的血脑屏障分布情况:以AUC_(0-t,brain)/AUC_(0-t,blood)计,麻黄碱类>甲基麻黄碱类>去甲基麻黄碱类。麻黄生物碱能够在血脑屏障间快速分布,在中枢系统分布具有组织趋向性,不同生物碱的血脑分布情况具有差异性。本文为中药麻黄的中枢作用机制研究提供了物质效应部位与依据。

关键词：麻黄生物碱中枢系统 UHPLC-QTOF-MSE UHPLC-MS/MS

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