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Weijia Zheng,Runquan Huang,Meijin Lin,Fang Guo,YangQuan Chen,Xiaohong Wang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.4
A fractional order sliding mode control (FOSMC) method is developed in this paper to deal with the control problem of permanent magnet synchronous motor (PMSM) speed servo system subject to multiple disturbances including model uncertainties, unknown constant disturbances and harmonic disturbances. The lumped exogenous disturbances and uncertainties of the PMSM speed servo are estimated by an improved disturbance observer (DO) and an extended state observer (ESO), respectively. Then, a novel FOSMC law is developed by incorporating the feedforward compensation and a fractional order switching law. The stability of the closed-loop system is established based on Lyapunov stability approach. Under the FOSMC scheme, the tracking performance and robustness of the PMSM servo system are improved simultaneously in the presence of mismatched disturbance torques and measurement noise. The effectiveness and advantages of the proposed method are demonstrated by the PMSM speed regulation experiments and the comparisons with some existing methods.
Zheng, Weijia,Park, Jin-A.,Abd El-Aty, A.M.,Kim, Seong-Kwan,Cho, Sang-Hyun,Choi, Jeong-min,Yi, Hee,Cho, Soo-Min,Ramadan, Amer,Jeong, Ji Hoon,Shim, Jae-Han,Shin, Ho-Chul Elsevier 2018 Journal of chromatography. B, Analytical technolog Vol.1072 No.-
<P><B>Abstract</B></P> <P>Over the past few decades, honey products have been polluted by different contaminants, such as pesticides, which are widely applied in agriculture. In this work, a modified EN – quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method was developed for the simultaneous quantification of pesticide residues, including cymiazole, fipronil, coumaphos, fluvalinate, amitraz, and its metabolite 2,4-dimethylaniline (2,4-DMA), in four types of honey (acacia, wild, chestnut, and manuka) and royal jelly. Samples were buffered with 0.2M dibasic sodium phosphate (pH 9), and subsequently, acetonitrile was employed as the extraction solvent. A combination of primary secondary amine (PSA) and C18 sorbents was used for purification prior to liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI<SUP>+</SUP>/MS-MS) analysis. The estimated linearity measured at six concentration levels presented good correlation coefficients (<I>R<SUP>2</SUP> </I>)≥0.99. The recovery, calculated from three different spiking levels, was 62.06–108.79% in honey and 67.58–106.34% in royal jelly, with an RSD<12% for all the tested compounds. The matrix effect was also evaluated, and most of the analytes presented signal enhancement. The limits of quantification (LOQ) ranged between 0.001 and 0.005mg/kg in various samples. These are considerably lower than the maximum residue limits (MRL) set by various regulatory authorities. A total of 43 market (domestic and imported) samples were assayed for method application. Among the tested samples, three samples were tested positive (i.e. detected and quantified) only for cymiazole residues. The residues in the rest of the samples were detected but not quantified. We concluded that the protocol developed in this work is simple and versatile for the routine quantification of cymiazole, 2,4-DMA, fipronil, coumaphos, amitraz, and fluvalinate in various types of honey and royal jelly.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Six pesticide residues in four types of honey and royal jelly were determined by LC–MS/MS analysis. </LI> <LI> Samples were extracted by a modified EN-QuEChERS method using both C18 sorbent and PSA. </LI> <LI> Recovery was good when the honey samples were extracted with 0.2M dibasic sodium phosphate buffer and acetonitrile. </LI> <LI> Three of the market samples tested positive for cymiazole residues. </LI> </UL> </P>
Zheng, Weijia,Park, Jin-A,Abd El-Aty, A.M.,Kim, Seong-Kwan,Cho, Sang-Hyun,Choi, Jeong-Min,Yi, Hee,Cho, Soo-Min,El-Banna, H.A.,Shim, Jae-Han,Chang, Byung-Joon,Wang, Jing,Kim, Jin-Suk,Shin, Ho-Chul Elsevier 2017 Journal of chromatography. B, Analytical technolog Vol.1064 No.-
<P><B>Abstract</B></P> <P>Herein, we developed a simple analytical procedure for the quantitation of bithionol residues in animal-derived food products such as porcine muscle, eggs, milk, eel, flatfish, and shrimp using a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method coupled with liquid chromatography–electrospray ionization tandem mass spectrometry (LC-ESI<SUP>+</SUP>/MS-MS). Samples were extracted with 0.1% solution of formic acid in acetonitrile and the extract was purified using a C18 sorbent. Separation was performed on a Waters XBridge™ C18 reversed-phase analytical column using 0.1% solution of formic acid/acetonitrile as the mobile phase. Six-point matrix-matched calibration indicated good linearity, with the calculated coefficients of determination (<I>R</I> <SUP>2</SUP>) being≥0.9813. Intra- and inter-day recoveries (determined at spiking levels equivalent to 1×and 2×the limit of quantitation (0.25μg/kg)) ranged between 80.0 and 94.0%, with the corresponding relative standard deviations (RSDs) being≤8.2%. The developed experimental protocol was applied to different samples purchased from local markets in Seoul, which were tested negative for bithionol residues. In conclusion, the proposed method proved to be versatile and precise, being ideally suited for the routine detection of bithionol residues in animal-derived food products with various protein and fat contents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bithionol residues were quantified in porcine muscle, whole milk, eggs, eel, flatfish, and shrimp. </LI> <LI> Samples were extracted using a modified EN-QuEChERS method followed by LC–MS/MS analysis. </LI> <LI> Satisfactory extraction efficiency was obtained using 0.1% formic acid in acetonitrile as an extractant. </LI> <LI> None of the market samples tested positive for the target analyte. </LI> <LI> The developed method can help establish the MRL of bithionol, which is yet to be set by regulatory authorities. </LI> </UL> </P>
Zheng, Weijia,Park, Jin-A,Zhang, Dan,Abd El-Aty, A.M.,Kim, Seong-Kwan,Cho, Sang-Hyun,Choi, Jeong-Min,Shim, Jae-Han,Chang, Byung-Joon,Kim, Jin-Suk,Shin, Ho-Chul Elsevier 2017 Journal of chromatography. B, Analytical technolog Vol.1058 No.-
<P><B>Abstract</B></P> <P>A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method coupled with liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI<SUP>+</SUP>/MS-MS) was developed for quantification of fenobucarb residues in animal food products, such as porcine muscle, egg, and whole milk, and aquatic food products, such as eel, flatfish, and shrimp. Acetonitrile with the addition of 0.1% trifluoroacetic acid was employed as an extraction solvent and was compared with acetonitrile alone and 0.1% formic acid in acetonitrile. All extracted samples were purified using C18 sorbent. The best extraction efficiencies, expressed as recovery at two spiking levels equivalent to 1- and 2-times the limit of quantification (LOQ=2μg/kg) were achieved using 0.1% trifluoroacetic acid in acetonitrile and ranged from 61.38 to 102.21% in all matrices, with relative standard deviations (RSDs) < 13% (except for the low spiking of porcine muscle and the high spiking of whole milk, for which the RSDs were>20%). Six-point matrix-matched calibration was used for quantification and the determination coefficients were good (<I>R<SUP>2</SUP> </I> ≥0.9865). The method was verified by application to samples purchased from local markets and none of the samples tested positive. In conclusion, the developed method is simple and versatile and can be used for the routine detection of fenobucarb in different animal food products having varying protein and fat contents with satisfactory accuracy and precision.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fenobucarb residues in animal and aquatic food products were determined by LC–MS/MS analysis. </LI> <LI> Samples were extracted with a modified QuEChERS method. </LI> <LI> Recovery was good when samples were extracted with 0.1% trifluoroacetic acid in acetonitrile. </LI> <LI> None of the market samples tested positive for fenobucarb residues. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Cho, Sang-Hyun,Park, Jin-A,Zheng, Weijia,Abd El-Aty, A.M.,Kim, Seong-Kwan,Choi, Jeong-Min,Yi, Hee,Cho, Soo-Min,Afifi, Nehal A.,Shim, Jae-Han,Chang, Byung-Joon,Kim, Jin-Suk,Shin, Ho-Chul Elsevier 2017 Journal of chromatography. B, Analytical technolog Vol.1065 No.-
<P><B>Abstract</B></P> <P>In this study, a simple analytical approach has been developed and validated for the determination of bupivacaine hydrochloride and isoflupredone acetate residues in porcine muscle, beef, milk, egg, shrimp, flatfish, and eel using liquid chromatography-tandem mass spectrometry (LC–MS/MS). A 0.1% solution of acetic acid in acetonitrile combined with <I>n</I>-hexane was used for deproteinization and defatting of all tested matrices and the target drugs were well separated on a Waters Xbridge™ C18 analytical column using a mobile phase consisting of 0.1% acetic acid (A) and 0.1% solution of acetic acid in methanol (B). The linearity estimated from six-point matrix-matched calibrations was good, with coefficients of determination ≥0.9873. The limits of quantification (LOQs) for bupivacaine hydrochloride and isoflupredone acetate were 1 and 2ngg<SUP>−1</SUP>, respectively. Recovery percentages in the ranges of 72.51–112.39% (bupivacaine hydrochloride) and 72.58–114.56% (isoflupredone acetate) were obtained from three different fortification concentrations with relative standard deviations (RSDs) of <15.14%. All samples for the experimental work and method application were collected from the local markets in Seoul, Republic of Korea, and none of them tested positive for the target drugs. In conclusion, a simple method using a 0.1% solution of acetic acid in acetonitrile and <I>n</I>-hexane followed by LC–MS/MS could effectively extract bupivacaine hydrochloride and isoflupredone acetate from porcine muscle, beef, milk, egg, shrimp, flatfish, and eel samples.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A method for determination of bupivacaine hydrochloride and isoflupredone acetate has been developed and validated. </LI> <LI> Residues were determined in porcine muscle, beef, milk, egg, shrimp, flatfish, and eel samples using LC–MS/MS. </LI> <LI> Solution of 0.1% of acetic acid in acetonitrile and <I>n</I>-hexane was used as a simple sample preparation. </LI> <LI> Monitoring was performed following the developed method and none of the samples were tested positive. </LI> </UL> </P>
Park, Jin-A.,Abd El-Aty, A.M.,Zheng, Weijia,Kim, Seong-Kwan,Cho, Sang-Hyun,Choi, Jeong-min,Hacımü,ftü,o, Ahmet,Jeong, Ji Hoon,Wang, Jing,Shim, Jae-Han,Shin, Ho-Chul Elsevier 2018 Food chemistry Vol.252 No.-
<P><B>Abstract</B></P> <P>A chromatographic method involving a single run was validated for the quantification of clanobutin, dichlorvos, and naftazone in products of animal origin. Pork, beef, chicken, milk, and egg samples were extracted with a solution of 0.1% formic acid in acetonitrile, defatted with <I>n</I>-hexane, centrifuged, and filtered prior to analysis using liquid chromatography-tandem mass spectrometry (LC-/MS/MS). The analytes were separated on a C18 column using a solution of 0.1% formic acid and 10 mM ammonium formate (A) and acetonitrile (B) as the mobile phase. A good linearity over 5–50 ng/g concentration range was obtained with coefficients of determination (<I>R<SUP>2</SUP> </I>) ≥ 0.9807. The intra- and interday accuracy (recovery %) calculated from 3 fortification levels (5, 10, and 20 ng/g) were 73.2–108.1% and 71.4–109.8%, and the precisions (expressed relative standard deviations (RSDs)) were 0.9–12.9% and 1.8–10.6%, respectively, for the 3 tested analytes in animal originated foods. The limits of quantification (LOQs) ranged between 0.1 and 1 ng/g, thus enabling the quantification of residual levels below the uniform maximum residue limit (MRL) of 0.01 mg/kg set for compounds having no MRL. The designated methodology was successfully applied to monitor various samples collected from Seoul; the tested analytes were not quantified in any of the market samples. Conclusively, the developed method is simple, sensitive, and accurate, and could be used for the detection of pharmaceuticals in various animal food matrices with variable protein and fat contents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Three drugs were quantified in various food products using LC–MS/MS. </LI> <LI> Samples were extracted using liquid-phase extraction (LPE) or EN-QuEChERS. </LI> <LI> The LPE efficiency using 0.1% formic acid in acetonitrile was superior to that of EN-QuEChERS with cleanup. </LI> <LI> The validation parameters were satisfactory for all tested drugs in various matrices. </LI> <LI> The method can be adopted for various matrices containing protein and fat. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>