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A New Compound from the Bud of Chrysanthemum indicum L.

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Chinese Chemical Letters 2005年第10期16卷 1341-1342页

作者： Wen ming CHENG tian Pa YOU Jun li Department of Chemistry University of Science and Technology of China Hefei 230026 School of Pharmacy Anhui Medical University Hefei 230032

A new bicyclic spiroketone was isolated from the bud of Chrysanthemum indicum L. The chemical structure was elucidated as （1R, 9S, 10S）-10-hydroxyl-8 （2＇, 4＇-diynehexylidene）- 9-isovaleryloxy-2, 7-dioxaspiro [5,... 详细信息

关键词： Chrysanthemum indicum L. X-ray crystallography bicyclic spiroketone (1R 9S,10S)-10-hydroxyl-8 (2' 4'-diynehexylidene)-9-isovaleryloxy-2 7-dioxaspiro[5 4]decane.

MATHEMATICAL SIMULATION OF NAVIGATION CHANNEL CHANGES IN THE FLUCTUATING BACKWATER REGION OF THE THREE GORGES RESERVOIR

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Journal of Hydrodynamics 1993年第2期5卷 63-68页

作者： li, Yi-tian Xie, Jian-heng Wu, Wei-ming Wuhan Univ of Hydraulic and Electric Engineering Wuhan China

In this paper, an one- and two-dimensional connected mathematical model is developed. The two-dimensional characteristics of flow and sediment transport are considered as much as possible in the model. The model is calibrated with field data and applied to simulate the river process of the fluctuating backwater region of the Three Gorges Reservoir. Some conclusions have been made based on the simulation results.

关键词： Channel flow Differential equations Mathematical models Rivers Sediment transport

Recursive Bayesian Algorithm for Identification of Systems with Non-uniformly Sampled Input Data

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International Journal of Automation and computing 2018年第3期15卷 335-344页

作者： Shao-Xue Jing tian-Hong Pan Zheng-ming li School of Electrical Information and Engineering Jiangsu University Department of Electrical Engineering Huaian College of Information and Technology

To identify systems with non-uniformly sampled input data, a recursive Bayesian identification algorithm with covariance resetting is proposed. Using estimated noise transfer function as a dynamic filter, the system with colored noise is transformed into the system with white noise. In order to improve estimates, the estimated noise variance is employed as a weighting factor in the algorithm. Meanwhile, a modified covariance resetting method is also integrated in the proposed algorithm to increase the convergence rate. A numerical example and an industrial example validate the proposed algorithm.

关键词： Parameter estimation discrete time systems Gaussian noise Bayesian algorithm covariance resetting.

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

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Acta Metallurgica Sinica(English Letters) 2019年第6期32卷 755-763页

作者： tian-Yi Sun Yan-Jun Guo Yi-ming Jiang Jin li Department of Materials Science Fudan University

The effect of short-time aging in the temperature range between 400 and 1000°C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS)2002 was investigated through the potentiostatic critical pitting temperature(CPT)tests and the Charpy impact *** the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650°C *** CPT of LDSS 2002 specimen aged at 650°C decreased by 28°C,and the impact energy dropped from 69 to 29 J/cm2 compared with the solution-annealed *** electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr2N and M23C6 along the ferrite–austenite grain boundaries.

关键词： Lean duplex stainless steel Aging Pitting corrosion Impact energy Precipitates

The interaction between dietary marine components and intestinal flora

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Marine life Science & Technology 2020年第2期2卷 161-171页

作者： lin li Chang-Hu Xue tian-tian Zhang Yu-ming Wang College of Food Science and Engineering Ocean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

The intestine is the natural habitat for a large and dynamic bacterial community,which perform vital metabolic and immune functions that significantly effect the nutritional and health status of the *** major physiological functions of intestinal flora include metabolic activities that lead to important trophic effects on immune structure and function as well as protection of the colonized host against invasion by transient *** intestinal flora is both a target for nutritional intervention and a factor influencing the biological activity of food compounds acquired *** environments,as a source of diverse organic compounds,can supply us with a number of beneficial and health-promoting *** review focuses on the physiological functions of intestinal flora and reciprocal interactions between intestinal flora and dietary marine components including polysaccharides,lipids,protein,taurine,carotenoids,minerals,and *** review can serve as a valuable reference regarding the consumption of seafood and marine nutraceuticals.

关键词： Intestinal flora Physiological function Dietary marine components Interaction

Bimetallic water oxidation: One-site catalysis with two-sites oxidation

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Journal of Energy Chemistry 2021年第12期30卷 1-7,I0001页

作者： Fei Xie ming-tian Zhang Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084China

Water oxidation is the key half reaction to achieve full splitting of water to hydrogen and ***,a binuclear complex,[(L^(4-))Co_(2)~Ⅲ(OH)]ClO_(4),was reported as a stable and efficient homogenous catalyst for electrocatalytic water oxidation in 0.1 M phosphate buffer(pH 7.0).Cyclic voltammetry experiments indicated that the catalytic process proceed via "one-site catalysis with two-sites oxidation" mechanism in which both two metal sites store the required oxidation equivalents for water oxidation and O-O bond formation occurs by single-site water nucleophilic attack(WNA).

关键词： Water oxidation Bimetallic catalysis O-O bond formation Cobalt catalyst Oxygen evolution

Distribution patterns of octylphenol and nonylphenol in the aquatic system at Mai Po Marshes Nature Reserve,a subtropical estuarine wetland in Hong Kong

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Journal of Environmental Sciences 2007年第6期19卷 657-662页

作者： li Xiang-li LUAN tian-gang liANG Yan WONG ming-hung LAN Chong-yu Croucher Institute for Environmental Sciences and Department of Biology Hong Kong Baptist UniversityHong Kong China State Key Laboratory of Biocontrol School of life Sciences Sun Yat-Sen （Zhongshan） University Guangzhou 510275 China

Spatial and temporal distribution of octylphenol （OP） and nonylphenol （NP） in Mai Po Marshes, a subtropical estuarine wetland in Hong Kong, were investigated. Surface water samples were collected every month from 11 sites during the period of September- December 2004. Concentrations of OP and NP ranged from 11.3 to 348 ng/L and from 29 to 2591 ng/L, respectively. The high levels of NP and OP were found in November and December than in September and October. The levels of OP and NP have no significant spatial differences except September. Total organic matter in the sediments appeared to be an important factor in controlling the fate of these compounds in the aquatic environment.

关键词： octylphenol nonylphenol endocrine-disrupting chemicals Ramsar Site

Ultra-fine-Grained Ferrite Prepared from Dynamic Reversal Austenite During Warm Deformation

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 290-298页

作者： Hong-Bin li ming-Song Chen Ya-Qiang tian lian-Sheng Chen li-Qing Chen College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210China School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Key Laboratory of the Ministry of Education for Modern Metallurgy Technology Tangshan 063210China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

The ultra-fine-grained ferrite(UFGF) with the size of less than 1 μm is often difficult to be obtained for low-alloyed steel in practical production *** this study,considering the rod and wire production process,a new method for preparing the UFGF with submicron scale is proposed by warm deformation of six passes with total strain of 2.6,followed by the cooling process in Gleeble-3500 thermo-mechanical *** results show that the UFGF with an average size of 0.64 μm could be obtained via the phase transformation from austenite grains with an average size of 3.4 μm,which are achieved by the deformation-induced reversal austenization during the high strain rate warm *** main driving force for the reversal transformation is the *** the interval between the passes also plays an important role in the reversal austenization.

关键词： Ultra-fine-grained ferrite Dynamic reversal transformation(DRT) Warm deformation Deformation-induced reversal transformation Cooling process

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改进TD3算法的机械臂三维路径规划方法

电光与控制 2025年第1期32卷 100-105页

作者：马天李超杨嘉怡西安科技大学计算机科学与技术学院西安710000

在军事航空领域中,复杂任务对机械臂路径规划提出了挑战。针对双延迟深度确定性策略梯度(TD3)算法学习效率低、样本利用率低的问题,提出了一种改进的TD3算法(Recurrent-TD3算法)。首先,将LSTM结合到策略网络与价值网络中,捕获航空控制... 详细信息

在军事航空领域中,复杂任务对机械臂路径规划提出了挑战。针对双延迟深度确定性策略梯度(TD3)算法学习效率低、样本利用率低的问题,提出了一种改进的TD3算法(Recurrent-TD3算法)。首先,将LSTM结合到策略网络与价值网络中,捕获航空控制任务中的时间序列信息,增强对时间序列变化的响应能力,使其能够在决策时考虑历史动作和状态,提高网络的表达能力;然后,将事后经验回放(HER)技术集成到TD3算法中,以解决任务中稀疏奖励难以学习的问题,通过将未达到目标的经验转化为达到新目标的经验,从而更有效地利用样本;最后,设计了一种基于包围盒的碰撞检测流程,以提高机械臂在军用航空任务中的安全性。实验表明,该算法相比于其他算法能够更快地找到一条无碰撞的路径,且平均路径长度最短。

关键词：机械臂路径规则 TD3 长短期记忆网络事后经验回放技术

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