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Recent advances in phytochemistry and pharmacology of C_(21) steroid constituents from Cynanchum plants

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Chinese Journal of Natural Medicines 2016年第5期14卷 321-334页

作者： gu Xiao-jie HAO Da-Cheng Biotechnology Institute School of Environment Dalian Jiaotong University

Cynanchum is one of the most important genera in Asclepiadaceae family, which has long been known for its therapeutic effects. In this genus, 16 species are of high medicinal value. The extracts of the root and/or rhizome parts have been applied in traditional Chinese medicines(TCM) for the prevention and treatment of various illnesses for centuries. C21 steroids, as the typical constituents of Cynanchum species, possess a variety of structures and pharmacological activities. This review summarizes the comprehensive information on phytochemistry and pharmacology of C21 steroid constituents from Cynanchum plants, based on reports published between 2007 and 2015. Our aim is to provide a rationale for their therapeutic application, and to discuss the future trends in research and development of these compounds. A total of 172 newly identified compounds are reviewed according to their structural classifications. Their in vitro and in vivo pharmacological studies are also reviewed and discussed, focusing on antitumor, antidepressant, antifungal, antitaging, Na+/K+-ATPase inhibitory, appetite suppressing and antiviral activities. Future research efforts should concentrate on in vitro and in vivo biological studies and structure activity relationship of various C21 steroid constituents.

关键词： Asclepiadaceae Cynanchum C21 steroid constituents Phytochemical studies Pharmacological actions

Optimal allocation of hybrid energy storage for microgrids based on multi-attribute utility theory

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Journal of Modern Power Systems and Clean Energy 2018年第1期6卷 107-117页

作者： Xiaoshan FENG jie gu Xuefei guAN School of Electronic Information and Electrical EngineeringShanghai Jiao Tong University Research Center of New Technology Shanghai Electric Power Design Institute

To satisfy the requirements of high energy density,high power density,quick response and long lifespan for energy storage systems(ESSs),hybrid energy storage systems(HESSs)have been investigated for their complementary characteristics of‘high energy density components’and‘high power density components’.To optimize HESS combinations,related indices such as annual cost,fluctuation smoothing ability as well as safety and environmental impact have to be *** multiattribute utility method investigated in this paper is aimed to draw an overall conclusion for HESS allocation optimization in *** on multi-attribute utility theory,this method has significant advantages in solving the incommensurability and contradiction among multiple *** of determining the weights of various attributes subjectively,when adopting the multi-attribute utility method,the characteristics of attributes and the relation among them can be investigated ***,the proper utility function and merging rules are identified to achieve the aggregate utility which can reflect comprehensive qualities of HESSs.

关键词： Hybrid energy storage system(HESS) Capacity optimization Multi-attribute utility theory HESS combination evaluation Utility function

Adiabatic shear fracture prediction in high-speed cuttingat various negative rake angles and feeds

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Advances in Manufacturing 2018年第1期6卷 41-51页

作者： Li-Yao gu Min-jie Wang School of Mechanical Engineering & State-Key Laboratoryof Traction Power Southwest Jiaotong UniversityChengdu 610031 People's Republic of China Mould & Die Research Institute School of MechanicalEngineering Dalian University of TechnologyDalian 116024 People's Republic of China

The critical characteristics of adiabatic shearfracture （ASF） that induce the formation of isolated seg-ment chip in high-speed machining was further investi-gated. Based on the saturation limit theory, combining withthe stress and deformation conditions and the modifiedJohnson-Cook constitutive relation, the theoretical predic-tion model of ASF was established. The predicted criticalcutting speeds of ASF in high-speed machining ofa hardened carbon steel and a stainless steel were verifiedthrough the chip morphology observations at various neg-ative rake angles and feeds. The influences of the cuttingparameters and thermal-mechanical variables on theoccurrence of ASF were discussed. It was concluded thatthe critical cutting speed of ASF in the hardened carbonsteel was higher than that in the stainless steel under alarger feed and a lower negative rake angle. The proposedprediction model of ASF could predict reasonable results ina wide cutting speed range, facilitating the engineeringapplications in high-speed cutting operations.

关键词： Stress wave Saturation limit Fracture Isolated segment Prediction

Distribution network state estimation based on attention-enhanced recurrent neural network pseudo-measurement modeling

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Protection and Control of Modern Power Systems 2023年第2期8卷 244-259页

作者： Yaojian Wang jie gu Lyuzerui Yuan Department of Electrical Engineering School of ElectronicsInformation and Electrical EngineeringShanghai Jiao Tong University209 of Smart Grid Building800 Dong Chuan RdShanghai 200240China

Because there is insufficient measurement data when implementing state estimation in distribution networks,this paper proposes an attention-enhanced recurrent neural network(A-RNN)-based pseudo-measurement modeling ***,based on analyzing the power series at the source and load end in the time and frequency domains,a period-dependent extrapolation model is established to characterize the power series in those *** complex mapping functions in the model are automatically represented by A-RNNs to obtain an A-RNNs-based period-dependent pseudo-measurement generation *** distributed dynamic state estimation model of the distribution network is established,and the pseudo-measurement data generated by the model in real time is used as the input of the state estimation model together with the measurement *** experimental results show that the method proposed can explore in depth the complex sequence characteristics of the measurement data such that the accuracy of the pseudo-measurement data is further *** results also show that the state estimation accuracy of a distribution network is very poor when there is a lack of measurement data,but is greatly improved by adding the pseudo-measurement data generated by the model proposed.

关键词： State estimation Pseudo measurement Recurrent neural network Attention mechanism Time-frequency domain analysis Distribution network

Resolution of DL-Pantolactone with Ethyldiamine Bridged Dimer Permethyβ-Cyclodextrin as GC Stationary Phase

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Chinese Chemical Letters 2001年第5期12卷 447-448页

作者： Dan Ni TAO Xue Yan SHI Jun Ling gu ruo Nong FU College of Chemical Engineering and Materials Science Beijing Institute of TechnologyBeijing 100081 Department of Application Chemistry Chinese Agriculture UniversityBeijing 100094

Ethyldiamine bridged dimer permethy-β-CD and other cyclodextrins were used as GC stationary phase to resolute DL-pantolactone. It is found that this CD dimer has a good selectivity for DL-pantolactone.

关键词： Cyclodextrin dimer gas chromatography stationary phase.

Network Coding-Aware Routing Protocol in Wireless Mesh Networks

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Tsinghua Science and Technology 2015年第1期20卷 40-49页

作者： Yan gu Han Han Xujie Li jie guo College of Computer and Information Hohai University

Network coding mechanisms, such as COPE, can improve network throughput effectively in Wireless Mesh Networks（WMN）. While the Hybrid Wireless Mesh Protocol（HWMP） is suitable for WMN, its extension with COPE does not provide any added benefits; specifically, HWMP cannot establish paths with more coding opportunities. As a result, the advantages of network coding cannot be exploited sufficiently. This paper proposes improvements upon HWMP with a new, network Coding-Aware routing protocol（CAHWMP） for WMN. In the CAHWMP protocol, we propose a coding criterion based on data streams to devise an algorithm for actively detecting coding opportunities during path discovery. CAHWMP subsequently establishes paths using the codingaware routing metric, which can balance channel resource consumption and the gain due to sharing resources introduced by network coding. Simulation results show that CAHWMP can establish paths with more coding opportunities; as a result, it improves network performance such as network throughput.

关键词： wireless mesh network network coding-aware Hybrid Wireless Mesh Protocol(HWMP) COPE mechanism coding criterion

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高压泡沫涨裂破岩特性试验研究

岩土工程学报 2025年第1期47卷 125-134页

作者：刘送永崔松顾聪聪中国矿业大学机电工程学院江苏徐州221116 中国矿业大学智能采矿装备技术全国重点实验室江苏徐州221116 安徽理工大学机电工程学院安徽淮南232001

针对钻爆法和机械法在岩石破碎工程中的弊端,基于泡沫的高黏性和可压缩性,提出了高压泡沫涨裂破岩技术。首先设计高压泡沫涨裂破岩装置,理论分析高压泡沫瞬间释放冲击岩石涨裂孔过程,搭建高压泡沫涨裂力测试装置并开展涨裂力影响试验,... 详细信息

针对钻爆法和机械法在岩石破碎工程中的弊端,基于泡沫的高黏性和可压缩性,提出了高压泡沫涨裂破岩技术。首先设计高压泡沫涨裂破岩装置,理论分析高压泡沫瞬间释放冲击岩石涨裂孔过程,搭建高压泡沫涨裂力测试装置并开展涨裂力影响试验,建立高压泡沫涨裂破岩试验系统,探讨不同空气体积分数时的泡沫涨裂特性,揭示高压泡沫涨裂破岩机理。研究表明:高压泡沫释放时,能够在涨裂孔内产生比泡沫初始压力更高的涨裂力,但涨裂力随泡沫空气体积分数增加而先增大后减小,高压泡沫涨裂破岩经历了裂纹初生、裂纹扩展、涨裂抛掷、涨裂结束4个阶段,破岩重量随泡沫空气体积分数的增加而先增大后减小,当空气体积分数为60%时,由高压泡沫冲击涨裂孔产生的压应力波在岩石上表面反射形成的拉应力造成岩石破坏形式为涨裂坑,空气体积分数为70%~90%时,泡沫涨裂形式为大块岩石分离,这主要是由孔底直角处应力集中效应造成。

关键词：高压泡沫涨裂破岩裂纹扩展涨裂力

Hygroscopic properties of sodium and potassium salts as related to saline mineral dusts and sea salt aerosols

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Journal of Environmental Sciences 2020年第9期32卷 65-72页

作者： Huanhuan Zhang Wenjun gu Yong jie Li Mingjin Tang State Key Laboratory of Organic Geochemistry and guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Department of Civil and Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoAvenida da UniversidadeTaipaMacaoChina University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Mineral dust,soil,and sea salt aerosols are among the most abundant primary inorganic aerosols in the atmosphere,and their hygroscopicity affects the hydrological cycle and global *** investigated the hygroscopic behaviors of six Na-and K-containing salts commonly found in those primary organic *** hygroscopic growths as a function of relative humidity(RH) agree well with thermodynamic model *** dependence of deliquescence RH(DRH) values for five of those salts was also investigated,which are comparable to those in literature within 1%-2% RH,most showing negative dependence on *** growth curves of real-world soil and sea salt samples were also *** hygroscopic growths of two more-hydroscopic saline soil samples and of sea salt can be predicted by the thermodynamic model based on the measured water-soluble ionic *** substantial amounts of water-soluble ions,including Na+and K+,in saline soil samples imply that even nascent saline soil samples are quite hygroscopic at high-RH(>80%) *** three less-hygroscopic dust samples,however,measurements showed higher water uptake ability than that predicted by the thermodynamic *** small amount of water taken up by less-hygroscopic dust samples suggests that dust particles might contain thin layers of water even to very low *** results of this study provide a comprehensive characterization of the hygroscopicity of Na-and K-containing salts as related to their roles in the hygroscopic behaviors of saline mineral dusts and sea salt aerosols.

关键词： prediction. salts dust

Investigating Desiderius Erasmus’ Copia and Its Semiotic Meaning: A Case Study of Angela Carter's Nights at the Circus

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Language and Semiotic Studies 2021年第2期7卷 101-120页

作者： jie gu Beijing Foreign Studies University China

Desiderius Erasmus?"Copia"is not only inscribed with rhetorical interpretations but also implied with semiotic *** paper starts from the definition,components,and functions of"Copia"and then analyzes Nights at the Circus from two aspects:the abundance of expression and the abundance of subject-matter,through discussing the employment of metaphor and antonomasia,the dividing of a whole into parts,and the tracing of causes in this *** research finds that the use of"Copia"can not only contribute to the richness and variety of style but also highlight the characters?personalities and enable Angela Carter to discuss political and social issues such as patriarchy and individual *** a perspective of Bakhtin's cultural semiotics,the paper aims to explore"Copia"semiotic meanings in literary classics and provide alternative interpretations of this conception in literary criticism.

关键词： Copia carnivalization Nights at the Circus