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Comparative pharmacokinetics of borneol in cerebral ischemia-reperfusion and sham-operated rats

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第1期15卷 84-91页

作者： Pan XU Ying li Shou-ying DU Yang LU Jie BAI Qing-li GUO Department of Industrial Pharmacy School of Chinese Pharmacy Beij ing University of Chinese Medicine Beij'ing 100102 China

Objective： This study was designed to investigate the pharmacokinetics of borneol in the pathological conditions of stroke and evaluate the pharmacokinetic differences of borneol caused by stroke after oral administration of borneol and Xingnaojing （XNJ）. Methods： The rats were divided into two groups, ischemia-reperfusion （IR） and sham-operated （SO） rats. Each group contained two subgroups： pure borneol and XNJ subgroups. After administration with the same dosages of borneol 162.0 mg/kg, plasma samples were collected. The cerebral ischemia-reperfusion model was created by reversible middle cerebral artery occlusion （MCAO）. The blood samples were collected punc- tually after oral administration and a specific gas chromatographic system-flame ionization detector （GC-FID） method was developed and employed to determine the level of borneol in the plasma. The pharmacokinetic parameters were analyzed using non-compartmental methods with Kinetica. Results： After administration of borneol, the maximum plasma concentration （Cmax） and area under the curve （AUC） values in stroke rats significantly increased by 302% and 275%, respectively, compared with the SO rats, and the same phenomenon appeared after administration of XNJ. In the rats with the same physiological conditions, the Cmax and AUC had higher values in the borneol subgroup （P〈0.05）. Conclusions： These results suggest that the pathological damages of ischemia-reperfusion have a significant impact on the pharmacokinetic traits of borneol and that there are some components in XNJ inhibiting the absorption of borneol.

关键词： Borneol Pharmacokinetics Cerebral ischemia-reperfusion Xingnaojing

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Cu_(2−x)S derived copper nanoparticles:A platform for unraveling the role of surface reconstruction in efficient electrocatalytic CO_(2)-to-C_(2)H_(4)conversion

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Nano Research 2023年第4期16卷 4494-4498页

作者： Chaohua He Delong Duan Jingxiang Low Yu Bai Yawen Jiang Xinyu Wang Shuangming Chen Ran Long li Song Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale Frontiers Science Center for Planetary Exploration and Emerging TechnologiesSchool of Chemistry and Materials Scienceand National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Hefei Comprehensive National Science Center 350 Shushanhu Rd.Hefei 230031China

Cu-based electrocatalysts have provoked much attention for their high activity and selectivity in carbon dioxide(CO_(2))conversion into multi-carbon ***,during the electrochemical reaction,Cu catalysts inevitably undergo surface reconstruction whose impact on CO_(2)conversion performance remains *** we report that polycrystalline Cu nanoparticles(denoted as Cu-s)with rich high-index facets,derived from Cu_(2−x)S through desulphurization and surface reconstruction,offer an excellent platform for investigating the role of surface reconstruction in electrocatalytic CO_(2)*** the formation of Cu-s catalyst,the two stages of desulphurization and surface reconstruction can be clearly resolved by in situ X-ray absorption spectroscopy and OH−adsorption characterizations,which are well correlated with the changes in electrocatalytic *** turns out that the high CO_(2)conversion performance,achieved by the Cu-s catalyst(Faradic efficiency of 68.6%and partial current density of 40.8 mA/cm^(2)in H-cell toward C_(2)H_(4)production),is attributed to the increased percentage of high-index facets in Cu-s during the surface ***,the operando electrochemical Raman spectroscopy further reveals that the conversion of the CO_(2)into the C_(2)H_(4)on Cu-s is intermediated by the production of**** findings manifest that the surface reconstruction is an effective method for tuning the reaction intermediate of the CO_(2)conversion toward high-value multicarbon(C2+)chemicals,and highlight the significance of in situ characterizations in enhancing the understanding of the surface structure and its role in electrocatalysis.

关键词： CO_(2)electroreduction reaction surface reconstruction high-index facets ethylene(C_(2)H_(4)) Cu catalysts

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用于网架重构决策的节点重要度动态评价方法

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电力自动化设备 2017年第4期37卷 89-95页

作者：顾雪平李少岩李凯华北电力大学电气与电子工程学院河北保定071003

针对网架重构过程中,待恢复节点的拓扑重要性随网络逐步恢复而发生变化的特点,提出一种节点拓扑重要性的动态评价指标——动态节点重要度。在重构决策中,基于当前系统恢复状态,通过将已恢复节点合并成一个等效电源点,构造包含及不包含... 详细信息

针对网架重构过程中,待恢复节点的拓扑重要性随网络逐步恢复而发生变化的特点,提出一种节点拓扑重要性的动态评价指标——动态节点重要度。在重构决策中,基于当前系统恢复状态,通过将已恢复节点合并成一个等效电源点,构造包含及不包含等效电源点的2个待恢复网络,综合考虑待评价节点的收缩对2个网络的影响,计算出待评价节点的动态节点重要度指标。在此基础上,将所定义的动态节点重要度指标用于网架重构中机组恢复的路径优化问题。新英格兰10机39节点系统算例验证了所提动态节点重要度评价指标及路径优化方法的有效性。

关键词：黑启动网络重构动态节点重要度路径优化

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A hybrid CNN-LSTM model for diagnosing rice nutrient levels at the rice panicle initiation stage

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Journal of Integrative Agriculture 2024年第2期23卷 711-723页

作者： Fubing liao Xiangqian Feng Ziqiu li Danying Wang Chunmei Xu Guang Chu Hengyu Ma Qing Yao Song Chen School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou 310018China China National Rice Research Institute Chinese Academy of Agricultural SciencesHangzhou 310006China School of Agriculture Yangtze UniversityJingzhou 434025China

Nitrogen(N)and potassium(K)are two key mineral nutrient elements involved in rice *** diagnosis of N and K status is very important for the rational application of fertilizers at a specific rice growth ***,we propose a hybrid model for diagnosing rice nutrient levels at the early panicle initiation stage(EPIS),which combines a convolutional neural network(CNN)with an attention mechanism and a long short-term memory network(LSTM).The model was validated on a large set of sequential images collected by an unmanned aerial vehicle(UAV)from rice canopies at different growth stages during a two-year *** with VGG16,AlexNet,GoogleNet,DenseNet,and inceptionV3,ResNet101 combined with LSTM obtained the highest average accuracy of 83.81%on the dataset of Huanghuazhan(HHZ,an indica cultivar).When tested on the datasets of HHZ and Xiushui 134(xs134,a japonica rice variety)in 2021,the ResNet101-LSTM model enhanced with the squeeze-and-excitation(SE)block achieved the highest accuracies of 85.38 and 88.38%,*** the cross-dataset method,the average accuracies on the HHZ and xs134 datasets tested in 2022 were 81.25 and 82.50%,respectively,showing a good *** proposed model works with the dynamic information of different rice growth stages and can efficiently diagnose different rice nutrient status levels at EPIS,which are helpful for making practical decisions regarding rational fertilization treatments at the panicle initiation stage.

关键词： dynamic model of deep learning UAV rice panicle initiation nutrient level diagnosis image classification

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Calculation Model for the Propagation of Audible Noise from High Voltage Transmission lines

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高电压技术 2013年第8期39卷 2045-2052页

作者： li Xuebao CUI Xiang LU Tiebing HE Jiamei State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing 102206 China

Audible noise from high voltage transmission lines’ corona discharge has become one of the decisive factors affecting design of high voltage transmission lines, thus it is very important to study the spatial propagation characteristics of audible noise for its accurate pre- diction. A calculation model for the propagation of audible noise is presented in this paper, which is based on the basic equation of the sound wave and can involve the influences of the atmosphere absorption and ground effects. The effects of different ground impedances and the atmospheric attenuation on the distribution of sound pressure level are discussed in this paper. The results show that the atmospheric absorp- tion may increase the attenuation of the audible noise, and the ground surface affects both the amplitude and phase of the sound. The spatial distribution fluctuates considering the ground effects. The atmospheric attenuation and the ground effect are closely related to the frequency of the noise. In the frequency range of the audible noise, the influence of atmospheric attenuation on the spatial propagation characteristics is more obvious in high frequency while ground has significant influences in low frequency.

关键词：高压输电线路噪声传播计算模型大气衰减地面效应输电线路设计空间分布传播特性

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Establishment and reliability evaluation of the design space for HPLC analysis of six alkaloids in Coptis chinensis(Huanglian) using Bayesian approach

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Chinese Journal of Natural Medicines 2016年第9期14卷 697-708页

作者： DAI Sheng-Yun XU Bing ZHANG Yi li Jian-Yu SUN Fei SHI Xin-Yuan QIAO Yan-Jiang Research Center of Traditional Chinese Medicine Information Engineering Beijing University of Chinese Medicine Engineering Research Center of Key Technologies for Chinese Medicine Production and New Drug Development Ministry of Education

Coptis chinensis(Huanglian) is a commonly used traditional Chinese medicine(TCM) herb and alkaloids are the most important chemical constituents in it. In the present study, an isocratic reverse phase high performance liquid chromatography(RP-HPLC) method allowing the separation of six alkaloids in Huanglian was for the first time developed under the quality by design(Qb D) principles. First, five chromatographic parameters were identified to construct a Plackett-Burman experimental design. The critical resolution, analysis time, and peak width were responses modeled by multivariate linear regression. The results showed that the percentage of acetonitrile, concentration of sodium dodecyl sulfate, and concentration of potassium phosphate monobasic were statistically significant parameters(P lied to further evaluate the interactions between the three parameters on selected responses. Full quadratic models were built and used to establish the analytical design space. Moreover, the reliability of design space was estimated by the Bayesian posterior predictive distribution. The optimal separation was predicted at 40% acetonitrile, 1.7 g·m L-1of sodium dodecyl sulfate and 0.03 mol·m L-1 of potassium phosphate monobasic. Finally, the accuracy profile methodology was used to validate the established HPLC method. The results demonstrated that the Qb D concept could be efficiently used to develop a robust RP-HPLC analytical method for Huanglian.

关键词： Coptis chinensis Quality by Design(Qb D) Bayesian approach Analytical design space Accuracy profile

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Direct Synthesis of Zn_(1-x)Cd_xs (0≤x≤1) Quantum Dots in Aqueous Solution and Application in Biology

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Journal of Wuhan University of Technology(Materials Science) 2013年第2期28卷 265-268页

作者：黄克阳何声太 liU Yulan ZHANG Yongxiao li Yanan HOU Xiaoqin XU Hu SUN Minglin WEN lingang School of Materials Science and Engineering Tianjin Polytechnic University

A simple procedure was presented to directly synthesize Zn1_xCdxs （0 ≤x≤1） quantum dots （QDs） in aqueous solution. QDs＇ structures and properties were characterized by TEM （transmission electron microscopy）, XRD （X-ray diffraction） and fluorescence microscopy. For those as-synthesized Zn1_xCdxs QDs, when the molar ratio between Zn and Cd changed from 1 to 0, its photoluminescence （PL） emission peak shifted from 430 nm to 675 nm. PL emission quantum efficiency was up to 15%. The experiment results demonstrated that those alloyed QDs showed a good biocompatibility and could be used as labelling materials in cell biology.

关键词： Zn1_xCdxs quantum dot luminescence synthesis

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泡沫铝材料动态本构参数的实验确定

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爆炸与冲击 2015年第1期35卷 1-8页

作者：丁圆圆杨黎明王礼立宁波大学力学与材料科学研究中心浙江宁波315211

基于泡沫材料的动态刚性-线性硬化塑性-刚性卸载(D-R-LHP-R)模型,结合连续性方程,动量守恒方程及刚体的运动方程,得到了激波在泡沫材料中的量纲一消失位置xs/L0和动态屈服应力Yi、激波波速cp、冲击初始应变εi之间的如下关系式:xs=exp-... 详细信息

基于泡沫材料的动态刚性-线性硬化塑性-刚性卸载(D-R-LHP-R)模型,结合连续性方程,动量守恒方程及刚体的运动方程,得到了激波在泡沫材料中的量纲一消失位置xs/L0和动态屈服应力Yi、激波波速cp、冲击初始应变εi之间的如下关系式:xs=exp-ρ0cpviL0(Y)=e(σxp 1 i-Y)=exp(-ρ0c2pεiY)(a)采用Taylor-Hopkinson装置进行实验,当直接测得泡沫铝试样密度ρ0、边界初始应力σi、初始打击速度vi、泡沫铝杆原长L0及激波在泡沫铝杆中消失长度xs后,利用方程式(a)可反演求得D-R-LHP-R模型下的泡沫铝动态应力应变曲线。最后通过与泡沫铝准静态实验数据对比,表明该泡沫铝是应变率敏感性材料。

关键词：固体力学动态力学特性动态刚性-线性硬化塑性-刚性卸载(D-R-LHP-R)模型泡沫铝激波

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Partial Discharge Measurement and Analysis in High Voltage IGBT Modules Under DC Voltage

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CSEE Journal of Power and Energy Systems 2018年第4期4卷 513-523页

作者： Pengyu Fu Zhibin Zhao Xiang Cui Teng Wen Haoyu Wang Xuebao li Peng Zhang State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Global Energy Interconnection Research Institute State Grid Corporation of ChinaBeijing 102211China

Insulation performance of high voltage IGBT modules is one of the key attributes in power system ***,the existing standards of IGBT devices and research on the evaluation of insulation performance of high voltage IGBT modules are insufficient;for example,partial discharge resistance under DC voltage blocking condition is not *** this paper,a new test was proposed to allow the measurement of partial discharges in all the components of IGBT modules under DC *** topology of the measuring circuit is arranged in the polarity discrimination way to exclude the interference,and the voltage and discharge current waveforms during the partial discharge process are measured by the wideband time domain measurement *** to the proposed test,the discharge phenomenon of the IGBT modules below the rating voltage were detected.A comprehensive waveform analysis on the voltage and discharge current was performed,and the influence of the applied voltage on the waveform parameters was *** waveform parameters are influenced by the applied voltage and insulation structure,which enables the discrimination of the causes of the observed partial discharge in the IGBT module under DC voltage by the waveform analysis *** on the waveform analysis technique,the types and causes of the observed partial discharges were discussed and inferred,and the correctness of the inference was further verified by *** proposed test and waveform analysis technique provide the possibility to evaluate and distinguish partial discharges in the high voltage IGBT module under DC voltage,which may be helpful to insulation performance evaluation and insulation defect diagnosis in high voltage IGBT module.

关键词： DC voltage high voltage IGBT module insulation performance partial discharge measurement waveform analysis wideband time domain measurement

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气体绝缘金属封闭输电线路地震响应的薄弱部位及其响应规律

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高电压技术 2015年第5期41卷 1437-1445页

作者：李庆民李伯涛王健陈超李成榕李志兵华北电力大学电气与电子工程学院北京102206 中国电力科学研究院北京100192

针对地震中气体绝缘金属封闭输电线路(GIL)的潜在故障问题,基于海南昌江某项目220 kV GIL物理结构,建立了三相输电管道水平敷设下的3维有限元模型,并提出依据现行设计规范模拟GIL地震响应的分析方法。首先通过模态分析获得了GIL结构的... 详细信息

针对地震中气体绝缘金属封闭输电线路(GIL)的潜在故障问题,基于海南昌江某项目220 kV GIL物理结构,建立了三相输电管道水平敷设下的3维有限元模型,并提出依据现行设计规范模拟GIL地震响应的分析方法。首先通过模态分析获得了GIL结构的振型特性,利用反应谱分析方法研究了不同地震反应谱激励下GIL地震响应的薄弱部位;然后对不同地震激励下GIL的抗震性能进行了具体评估,并进一步对GIL薄弱部位的地震响应规律进行分析总结。结果表明:建模所依据的220 kV GIL输电管道结构能够耐受6度的地震烈度,但对于7度及以上的地震烈度,其有损坏的可能;绝缘子和导体是GIL结构地震响应的薄弱部位;合理选取绝缘子和导体的机械参数能有效提高GIL的抗震能力。

关键词：气体绝缘金属封闭输电线路地震响应模态振型反应谱分析抗震分析薄弱部位参数优化

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