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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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An exact algorithm for optimal redundancy in a series system with multiple component choices
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作者 孙小玲 阮宁 《Journal of Shanghai University(English Edition)》 CAS 2006年第1期15-19,共5页
In this paper, an exact algorithm was proposed for optimal redundancy in a series system with multiple component choices. A reformulation of the nonseparable reliability function was approximated by a separable intege... In this paper, an exact algorithm was proposed for optimal redundancy in a series system with multiple component choices. A reformulation of the nonseparable reliability function was approximated by a separable integer programming problem. The resulting separable nonlinear integer programming problem is used to compute upper bounds by Lagrangian relaxation and dual search. A special partition scheme was derived to reduce the duality gap in a branch-and-bound process, thus ensure the convergence of the algorithm. Computational results show that the algorithm is efficient for solving this class of reliability optimization problems. 展开更多
关键词 reliability optimization multiple component choices Lagrangian relaxation and dual search partition scheme numerical results.
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Performance of Relay Networks in Fading Environments with Dominant Specular Components
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作者 Lingwen Zhang Chang Liu +2 位作者 Jiayi Zhang Faen Wu Wenkao Yang 《China Communications》 SCIE CSCD 2016年第12期69-78,共10页
Radio propagation in dense and super dense wireless networks as well as indoor-to-outdoor picocell networks can have multiple line-of-sight or multiple specular components. The performance of a dual-hop decode-and-for... Radio propagation in dense and super dense wireless networks as well as indoor-to-outdoor picocell networks can have multiple line-of-sight or multiple specular components. The performance of a dual-hop decode-and-forward relaying system over multiple specular components fading channels(MSCC)with multiple Rayleigh distributed co-channel interferers in an interference-limited environment is investigated. The MSCC fading model is designed to allow direct and meaningful comparisons to be made between line-of-sight channels and non-line-of-sight channels, with exact parameter correspondences. Comparisons of outage and bit error performance between Nakagami-m/Rayleigh and MSCC/Rayleigh fading environments show that the MSCC model is needed to describe line-of-sight channels that cannot be accurately modeled by the Nakagami-m, or other fading models. 展开更多
关键词 multiple Specular components Channel(MSCC) cochannel interference decode-and-forward relay outage probability average bit error probability
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Preventive condition-based maintenance model of EMU components based on stochastic differential equation
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作者 HUANGFU Lanlan ZHAO Yifan SU Hongsheng 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第3期345-351,共7页
To improve the operation and maintenance management level of large repairable components,such as electrical equipment,large nuclear power facilities,and high-speed electric multiple unit(EMU),and increase economic ben... To improve the operation and maintenance management level of large repairable components,such as electrical equipment,large nuclear power facilities,and high-speed electric multiple unit(EMU),and increase economic benefits,preventive maintenance has been widely used in industrial enterprises in recent years.Focusing on the problems of high maintenance costs and considerable failure hazards of EMU components in operation,we establish a state preventive maintenance model based on a stochastic differential equation.Firstly,a state degradation model of the repairable components is established in consideration of the degradation of the components and external random interference.Secondly,based on topology and martingale theory,the state degradation model is analyzed,and its simplex,stopping time,and martingale properties are proven.Finally,the monitoring data of the EMU components are taken as an example,analyzed and simulated to verify the effectiveness of the model. 展开更多
关键词 preventive maintenance stochastic differential equation SIMPLEX MARTINGALE electric multiple unit components
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Intervention of multiple pathways by multiple active components provides potent protection against cerebral ischemia injury
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作者 张精亮 胡涛 +2 位作者 刘晓岩 朱元军 王银叶 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2014年第5期295-301,共7页
To explore the effect of multiple pathway intervention in acute cerebral ischemia injury, we prepared a medicine formula (formula 2) consisting of ginsenosides, pueraria flavonoids, ophiopogonis and borneol as a too... To explore the effect of multiple pathway intervention in acute cerebral ischemia injury, we prepared a medicine formula (formula 2) consisting of ginsenosides, pueraria flavonoids, ophiopogonis and borneol as a tool medicine. The effects of formula 2 and its components on PC12 cell viability and potential pathway were investigated, and the influence of this formula on venous thrombosis and platelet aggregation was also assessed, then the effect of formula 2 on middle cerebral artery occlusion (MCAO) reperfusion was observed in rats. Formula 2 markedly enhanced the cell viability, which was stronger than that of each individual component. Formula 2 significantly inhibited the NO production in PC12 cells induced by H202, and this effect was also stronger than that of each individual component. Moreover, formula 2 enhanced the SOD activity, and the effect was stronger than that of ginsenosides. In addition, formula 2 reduced the MDA content, and this effect was stronger than that of ophiopogonins. In vivo, formula 2 showed potent inhibitory effects on platelet aggregation and venous thrombosis. Furthermore, formula 2 (single dose, s.c.) significantly reduced the infarct volume and neurobehavioral scores in MCAO reperfusion rats. Take together, our results suggests that formula 2 has powerful ability of inhibiting the ischemia/reperfusion injury, and this effect might be attributed to its simultaneous intervention in the cascade reaction of neuronal injury via multiple pathways contributed by multiple components during cerebral ischemia/reperfusion. 展开更多
关键词 multiple pathways multiple components Cerebral ischemia/reperfusion injury Formula 2
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Synthesis of Multi-component Mass-exchange Networks 被引量:5
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作者 刘琳琳 都健 +2 位作者 Mahmoud M. EI-Halwagi Jose Maria Ponce-Ortega 姚平经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期376-381,共6页
This paper presents a superstructure-based formulation for the synthesis of mass-exchange networks (MENs) considering multiple components. The superstructure is simplified by directly using the mass separation agents ... This paper presents a superstructure-based formulation for the synthesis of mass-exchange networks (MENs) considering multiple components. The superstructure is simplified by directly using the mass separation agents (MSA) from their sources, and therefore the automatic synthesis of the multi-component system involved in the MENs can be achieved without choosing a 'key-component' either for the whole process or the mass exchangers. A mathematical model is proposed to carry out the optimization process. The concentrations, flow rates, matches and unit operation displayed in the obtained network constitute the exact representation of the mass exchange process in terms of all species in the system. An example is used to illustrate and demonstrate the application of the proposed method. 展开更多
关键词 multiple components mass exchange network SUPERSTRUCTURE OPTIMIZATION
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Decomposition of a gas mixture of four n-alkanes using a DBD reactor 被引量:1
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作者 Boqiong JIANG Xiaodan FEI +4 位作者 Shuiliang YAO Qinmin WANG Xinlei YAO Kai XU Zhizong CHEN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第11期74-80,共7页
This study investigates the decomposition of a gas mixture of four n-alkanes(n-heptane,n-octane,n-nonane,and n-decane)using a dielectric barrier discharge reactor.We show that the conversion of n-alkanes increased fro... This study investigates the decomposition of a gas mixture of four n-alkanes(n-heptane,n-octane,n-nonane,and n-decane)using a dielectric barrier discharge reactor.We show that the conversion of n-alkanes increased from 7.2%(C7H(16)),9.7%(C8H(18)),8.4%(C9H(20)),and 10.5%(C(10)H(22))to 23.8%(C7H(16)),25.0%(C8H(18)),27.9%(C9H(20)),and 32.1%(C(10)H(22))when the energy density increased from 84 J l^-1 to 324 J l^-1.The conversion of n-alkanes when using the gas mixture is close to that found when using a single n-alkane.The influences of reaction temperature and O2 concentration are also investigated,and the activation energies for the decomposition of each alkane are given. 展开更多
关键词 multiple components n-alkane decomposition dielectric barrier discharge energy efficiency activation energy
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A Fuzzy Clustering Algorithm Based on Multipath Component Trajectory for Millimeter Wave Radio Channels
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作者 Fei Du Yu Zhang +5 位作者 Qingliang Li Xinyue Zhang Bo Zhu Zihao Fu Suiyan Geng Xiongwen Zhao 《China Communications》 SCIE CSCD 2022年第11期99-111,共13页
Time-varying channel modeling plays an important role for many applications in time-variant scenarios,while most clustering algorithms focus on static channels and cannot accurately model the channel time-evolution pr... Time-varying channel modeling plays an important role for many applications in time-variant scenarios,while most clustering algorithms focus on static channels and cannot accurately model the channel time-evolution properties.In this paper,a fuzzy clustering algorithm based on multipath component(MPC)trajectory is proposed.Firstly,both the distance and velocity similarities of the MPCs in different snapshots are taken into account to track the MPC trajectory,in which the fuzzy scheme and a kernel function are used to calculate the distance and velocity similarities,respectively.Secondly,a fuzzy MPC trajectory clustering algorithm is proposed to cluster the MPCs in multiple snapshots.The MPCs in a snapshot are clustered according to the membership,which is defined as the probability that a MPC belongs to different clusters.Finally,time-varying channels at 28 GHz are simulated to validate the performance of our proposed algorithm.The results show that our proposed algorithm is able to accurately identify the clusters in time-varying channels compared with the existing clustering algorithms. 展开更多
关键词 channel modeling TIME-VARYING clustering multiple path component MPC trajectory 6G
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Simultaneous Determination of Seven Components in Gamboge and Its Processed Products Using a Single Reference Standard 被引量:1
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作者 Min Xu Hong-sheng Tan +4 位作者 Wen-wei Fu Ling-yun Pan Yue-xun Tang Shen-da Huang Yan-feng Xiu 《Chinese Herbal Medicines》 CAS 2017年第1期42-49,共8页
Objective To establish a quality control method for simultaneous determination of multiple components in gamboge. Methods A single reference standard for the determination of multiple components (SSDMC) with HPLC wa... Objective To establish a quality control method for simultaneous determination of multiple components in gamboge. Methods A single reference standard for the determination of multiple components (SSDMC) with HPLC was proposed. Seven major components of gamboge including gambogenic acid (S), β-morellic acid (C1), 2R-30-hydroxygambogic acid (C2), isogambogenic acid (C3), gambogellic acid (C4), 2R-gambogic acid (C5), and 2S-gambogic acid (C6) were simultaneously analyzed using gambogenic acid as reference standard. The credibility and feasibility of SSDMC method were validated with respect to linearity, limits of detection and quantification, precision, stability, repeatability, accuracy, ruggedness, and robustness. The relative conversion factors (RCFs) of S and C1-6 were calculated. Twelve batches of gamboge including crude and processed products were successfully analyzed by applying the SSDMC and traditional external standard (ES) methods. Results The SSDMC method was credible and feasible. The RCFs of S and C1-6 were 1.000, 0.913, 0.864, 1.064, 0.777, 0.921, and 0.919, respectively. No significant difference was observed in the contents of the seven components between SSDMC and ES methods. The heat-processing technique caused a reduction in the seven components. Conclusion SSDMC is a simple, reliable, and effective method for the analysis of the complex multiple components in gamboge, and it is also a practical and economical approach. 展开更多
关键词 gamboge HPLC quality control relative conversion factor single standard for determination of multiple components
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Gene Selection for Classifications Using Multiple PCA with Sparsity
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作者 Yanwei Huang Liqing Zhang 《Tsinghua Science and Technology》 SCIE EI CAS 2012年第6期659-665,共7页
A gene selection algorithm was developed using Multiple Principal Component Analysis with Sparsity (MSPCA). The MSPCA algorithm is used to analyze normal and disease gene expression samples and to set these componen... A gene selection algorithm was developed using Multiple Principal Component Analysis with Sparsity (MSPCA). The MSPCA algorithm is used to analyze normal and disease gene expression samples and to set these component Ioadings to zero if they are smaller than a threshold for sparse solutions. Next, genes with zero Ioadings across all samples (both normal and disease) are removed before extracting feature genes. Feature genes are genes that contribute differentially to variations in normal and disease samples and, thus, can be used for classification. The MSPCA is applied to three microarray datasets to select feature genes with a linear support vector machine to evaluate its performance. This method is compared with several previous gene selection results to show that this MSPCA gene selection algorithm has good classification accuracy and model stability. 展开更多
关键词 microarray gene expression gene selection multiple Principal Component Analysis with Sparsity (MSPCA) sparse
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Dehydrative Beckmann rearrangement and the following cascade reactions
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作者 Yongjiao Wei Yinghui Liu Lan-Gui Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第5期2407-2410,共4页
The Beckmann rearrangement has been predominantly studied for the synthesis of amide and lactam.By strategically using the in situ generated Appel’s salt or Mitsunobu’s zwitterionic adduct as the de-hydrating agent,... The Beckmann rearrangement has been predominantly studied for the synthesis of amide and lactam.By strategically using the in situ generated Appel’s salt or Mitsunobu’s zwitterionic adduct as the de-hydrating agent,a series of Beckmann rearrangement and following cascade reactions have been devel-oped herein.The protocol allows the conversion of various ketoximes into amide,thioamide,tetrazole and imide products in modular procedures.The generality and tolerance of functionalities of this method have been demonstrated. 展开更多
关键词 Beckmann rearrangement multiple components reaction AMIDE THIOAMIDE TETRAZOLE
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Science and technology in high-entropy alloys 被引量:96
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作者 张蔚冉 Peter K.Liaw 张勇 《Science China Materials》 SCIE EI CSCD 2018年第1期2-22,共21页
As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In rec... As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In recent years, high-entropy alloys(HEAs) have attracted tremendous attention in various fields. With multiple principal components, they inherently possess unique microstructures and many impressive properties, such as high strength and hardness, excellent corrosion resistance, thermal stability, fatigue,fracture, and irradiation resistance, in terms of which they overwhelm the traditional alloys. All these properties have endowed HEAs with many promising potential applications.An in-depth understanding of the essence of HEAs is important to further developing numerous HEAs with better properties and performance in the future. In this paper, we review the recent development of HEAs, and summarize their preparation methods, composition design, phase formation and microstructures, various properties, and modeling and simulation calculations. In addition, the future trends and prospects of HEAs are put forward. 展开更多
关键词 high-entropy alloys multiple principal components microstructures and properties phase formation modeling and simulation calculations
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Fmoc-protected amino acids as luminescent and circularly polarized luminescence materials based on charge transfer interaction 被引量:1
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作者 Yiran Xia Aiyou Hao Pengyao Xing 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第11期4918-4923,共6页
Fluorenylmethyloxycarbonyl(Fmoc)-protected amino acids are effective building blocks in self-assembled architectures at hierarchical levels,which however show limited luminescent properties and chiroptical activities.... Fluorenylmethyloxycarbonyl(Fmoc)-protected amino acids are effective building blocks in self-assembled architectures at hierarchical levels,which however show limited luminescent properties and chiroptical activities.Here we introduce a charge-transfer strategy to build two-component luminescent materials with emerged circularly polarized luminescence properties.A library of Fmoc-amino acids was built,which selectively form charge-transfer complexes with the electron-deficient acceptor.Embedding in amorphous polymer matrix or physical grinding could trigger the charge-transfer luminescence with adjusted wavelengths in a general manner.X-ray diffraction results suggest the multiple binding modes between donor and acceptor.And,the solution-processed coassembly could selectively exhibit circularly polarized luminescence with high dissymmetry g-factors.This work illustrates a noncovalent charge-transfer strategy to construct luminescent and chiroptical organic composites based on the easy-accessible and economic chiral N-terminal aromatic amino acids. 展开更多
关键词 Fmoc-amino acids Charge-transfer interaction Supramolecular chirality multiple component coassembly
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