Wyniki wyszukiwania - Biblioteka Nauki

1

Robust aperiodic-disturbance rejection in an uncertain modified repetitive-control system

100%

Zhou L. , She J. , Li C. , Pan C.

International Journal of Applied Mathematics and Computer Science

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2016

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tom Vol. 26, no. 2

285--295

EN

This paper concerns the problem of designing an EID-based robust output-feedback modified repetitive-control system (ROFMRCS) that provides satisfactory aperiodic-disturbance rejection performance for a class of plants with time-varying structured uncertainties. An equivalent-input-disturbance (EID) estimator is added to the ROFMRCS that estimates the influences of all types of disturbances and compensates them. A continuous-discrete two-dimensional model is built to describe the EID-based ROFMRCS that accurately presents the features of repetitive control, thereby enabling the control and learning actions to be preferentially adjusted. A robust stability condition for the closed-loop system is given in terms of a linear matrix inequality. It yields the parameters of the repetitive controller, the output-feedback controller, and the EID-estimator. Finally, a numerical example demonstrates the validity of the method.

2

Determination of chloramphenicol residues in honey by monolithic column liquid chromatography-mass spectrometry after use of quechers clean-up

88%

Pan C. , Zhang A. , Chen S. , Xu Y. , Jiang S.

Acta Chromatographica

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2006

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tom No. 17

320-327

EN

An HPLC method with a monolithic column and detection by mass spectrometry has been established for determination of chloramphenicol in honey samples previously cleaned by use of a modification of the QuEChERS procedure. Honey samples were dissolved in water containing sodium chloride and extracted with acetonitrile. Further sample clean-up was performed by simple reversed-solid-phase dispersion with primary–secondary amine (PSA) adsorbent. Chloramphenicol (CAP) residues at ppb concentrations were detected by liquid chromatography–mass spectrometry (LC–MS), with electrospray ionization, in negative-ion mode. The mobile phase was methanol–0.2% aqueous ammonium acetate solution, 45:55 (v/v). Under these conditions CAP is eluted after ∼4 min and 8 min from a Merck RP-18e monolithic column and a conventional C18 column, respectively. Recovery at three fortification levels (0.2, 20, and 200 µg kg.1) was in the range 78–93% with RSD from 3.7 to 3.9%. The coefficient of determination, R2, was 0.9995 over a 0.1–100 µg L.1 linear range. Use of this method for determination of CAP in honey resulted in an LCL of 0.20 µg kg.1. The method was validated on the basis of EU decision 2002/657. CCá and CCâ for the honey matrix were 0.002 and 0.006 µg kg.1, so the method was fit for the purpose of monitoring commercial products or checking MRL compliance.

3

Effects of seminal plasma concentration on sperm motility and plasma and acrosome membrane integrity in chilled canine spermatozoa

88%

Pan C. , Wu Y. , Yang Q. , Ye J.

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4

Hydrophilic-interaction liquid chromatography (HILIC) with dad and mass spectroscopic detection for direct analysis of glyphosate and glufosinate residues and for product quality control

75%

Li X. , Xu J. , Jiang Y. , Chen L. , Xu Y. , Pan C.

Acta Chromatographica

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2009

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tom Vol. 21, no. 4

559--576

EN

High-performance liquid chromatography with a hydrophilic-interaction liquid chromatographic (HILIC) column has been successfully used to retain and separate the polar phosphonic herbicides glyphosate and glufosinate. Online electrospray tandem ion-trap mass spectrometric and DAD detection were used. The effects on the separation of mobile phase acetonitrile content, buffer concentration, and flow rate, and of column temperature, were investigated. With UV-visible detection at 195 nm, LOQ were <850 mg kg -1, showing the method is suitable for product quality control of these herbicides alone or in combination. Tandem mass spectrometric conditions were optimized for ion-trap detection. Quantification was by use of selected reaction monitoring transitions m / z 168 → 150 in negative-ion mode for glyphosate and m / z 182 → 136 in positive-ion mode for glufosinate. Limits of detection (LOD; S / N > 3) were 0.20 and 0.16 ng for glyphosate and glufosinate, respectively, and the respective limits of quantification (LOQ; S / N = 10) were 0.02 and 0.05 mg kg -1 . Sample derivatization was not necessary to achieve low detection limits in residue analysis in this study. Recovery from watermelon, spinach, potato, tomato, radish-root, and water fortified with the herbicides ranged from 63.6 to 107.3% and relative standard deviations were <15.3%.

5

A planning model for the chemical integrated system under uncertainty by grey programming approach

75%

Ren J. , Tan S. , Dong L. , Zhou Z. , Gao S. , Pan C.

Polish Journal of Chemical Technology

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2013

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tom Vol. 15, nr 2

16--22

EN

A model to optimize the planning of the chemical integrated system comprised by multi-devices and multi-products has been proposed in this paper. With the objective to make more profits, the traditional model for optimizing production planning has been proposed. The price of chemicals, the market demand, and the production capacity have been considered as mutative variables, then an improved model in which some parameters are not constant has been developed and a new method to solve the grey linear programming has been proposed. In the grey programming model, the value of credibility can be suggested by the decision-makers, and the results of the production planning calculated by the model can help them to achieve their desired target. An actual case has been studied by the proposed methodology, and the proposed methodology can be popularized to other cases.

6

Optimization and validation of a method based on derivatization with methylating agent followed by HPLC-DAD for determining dithiocarbamates residues

75%

Zhou L. , Xu J. , Luan L. , Ma J. , Gong Y. , Qin D. , Pan C.

Acta Chromatographica

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2013

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tom Vol. 25, no. 4

613--625

EN

Dithiocarbamates fungicides (DTCs) are worldwidely used fungicides. Residue analytical methods on DTCs are usually based on headspace gas chromatography, which are not much stable and precise. In this study, a specific, simple and reliable method for determining DTCs fungicides residues was optimized and validated. The DTCs in foods and soils were extracted with an alkaline solution of EDTA and L-cysteine, followed by pH adjusting and methyl derivatization in methyl iodine solution. The organic layer of the reactants was separated, concentrated under vacuum and reconstructed in acetonitrile. DTCs residues were eluted on a C18 column and detected by HPLC-DAD at 272 nm. The S-alkyl derivatives of thiram, mancozeb and propineb were separated at different retention times. At fortified levels of 0.05 mg/kg to 2 mg/kg (residue expressed as CS2, in mg/kg, the same below), it is found that recoveries for DTCs spiked in apple, cucumber, tomato, rice and soil samples ranged from 70.8% to 105.3%, with relative standard deviations (RSD) from 0.6% to 13.7%. Limits of detection (LODs) and quantification (LOQs) ranged from 0.003 to 0.026 mg/kg and from 0.011 to 0.105 mg/kg for various foods and soils. This method was also applied to real sample tests.

7

Associations of six SNPs of POU1F1-PROP1-PITX1-SIX3 pathway genes with growth traits in two Chinese indigenous goat breeds

63%

Ma L. , Qin Q. , Yang Q. , Zhang M. , Zhao H. , Pan C. , Lei C. , Chen H. , Lan X.

Annals of Animal Science

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2017

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tom 17

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nr 2

8

RhoA/Rock2/Limk1/cofilin1 pathway is involved in attenuation of neuronal dendritic spine loss by paeonol in the frontal cortex of D‑galactose and aluminum‑induced Alzheimer’s disease‑like rat model

63%

Han F. , Xu H. , Shen J.-X. , Pan C. , Yu Z.-H. , Chen J.-J. , Zhu X. L. , Cai Y.-F. , Lu Y.-P.

Acta Neurobiologiae Experimentalis

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2020

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tom 80

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nr 3

EN

Alzheimer’s disease (AD) has become the most prevalent neurodegenerative disorder. Given the pathogenesis of AD is unclear, there is currently no drug approved to halt or delay the progression of AD. Therefore, it is pressing to explore new targets and drugs for AD. In China, polyphenolic Chinese herbal medicine has been used for thousands of years in clinical application, and no toxic effects have been reported. In the present study, using D‑galactose and aluminum‑induced rat model, the effects of paeonol on AD were validated via the Morris water maze test, open field test, and elevated plus maze test. Neuronal morphology in frontal cortex was assessed using ImageJ’s Sholl plugin and RESCONSTRUCT software. RhoA/Rock2/Limk1/cofilin1 signaling pathway‑related molecules were determined by Western blotting. Cofilin1 and p‑cofilin1 were analyzed by immunofluorescence. Results showed that pre‑treatment with paeonol attenuated D‑galactose and aluminum‑induced behavioral dysfunction and AD‑like pathological alterations in the frontal cortex. Accompanied by these changes were the alterations in the dendrite and dendritic spine densities, especially the mushroom‑type and filopodia‑type spines in the apical dendrites, as well as actin filaments. In addition, the activity and intracellular distribution of cofilin1 and the molecules RhoA/Rock2/Limk1 that regulate the signaling pathway for cofilin1 phosphorylation have also changed. Our data suggests that paeonol may be through reducing Aβ levels to alleviate the loss of fibrillar actin and dendrites and dendritic spines via the Rho/Rock2/Limk1/cofilin1 signaling pathway in the frontal cortex, and ultimately improving AD‑like behavior.