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determination of Residual Amount of 15 Plant Growth Regulators in Bean Sprouts by HPLC-MS/MS

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Agricultural Biotechnology 2021年第6期10卷 64-67页

作者： Lei WANG Yi ZHANG Baiqin ZHENG Shuai WANG Kai GE Sining TANG Shuhong ZHANG Liwu HAO Tangshan Food and Drug Comprehensive Testing Center Tangshan 063000China Hebei Agricultural products quality and Safety Testing Innovation Center Tangshan 063000China Tangshan Institute of Industrial Technology for Functional Agricultural products Tangshan 063000China

[Objectives]This study was conducted to effectively monitor PGR residues in bean sprouts to provide guarantee for the food safety of agricultural products.[Methods]A high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method for the determination of residues of 15 plant growth regulators(PGRs)in bean sprouts was established using bean sprouts as an experimental *** were extracted with a solution containing 5%acetic acid-acetonitrile(1∶99,V/V),purified with anhydrous magnesium sulfate,and diluted with methanol solvent to constant *** solutions were filtered through 0.22μm filtering membrane and the target analytes were separated on a Phenomenex H18 *** identification of each compound was established by retention time matching along with the accurate mass measurement of the precursor ions and their main fragment *** quantification was carried out using matrix-matched external standard method.[Results]The retention time of the 15 PGRs were found in the range from 5.8-11.7 min under the optimized *** linear relation was good in the concentration range of 0.005-0.050μg/ml,and the correlation coefficients of the 15 PGRs were≥*** limits of detection were in the range of 0.03-0.92 g/kg,and the limits of quantification were in the range of 0.50-2.10μg/*** average recovery in the recovery test at 3 concentration levels was 80%-110%,and the relative standard deviations were in the range of 2.8%-7.5%.[Conclusions]This method is simple and accurate,and can quickly qualitatively and quantitatively analyze the residues of 15 PGRs in bean *** proposed procedure was simple,quick and accurate for the simultaneous determination of the 15 PGRs in bean sprout.

关键词： High performance liquid chromatography-tandem mass spectrometry Bean sprout Plant growth regulator

determination of selected semi-volatile organic compounds in water using automated online solid-phase extraction with large-volume injection/gas chromatography/mass spectrometry

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Frontiers of Environmental Science & Engineering 2011年第3期5卷 417-425页

作者： Yongtao LI Christina L.MCCARTY Ed J.GEORGE Drinking Water quality Laboratory Underwriters Laboratories Inc.South BendIN 46617USA Chemical Analysis Bruker DaltonicsFremontCA 94538USA

A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in *** method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass *** samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction *** method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface *** a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most *** the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for *** new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other *** a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.

关键词： automated solid-phase extraction programmed-temperature vaporization large-volume injection gas chromatography/mass spectrometry semi-volatile organic compounds water analysis

Stereoselective separation and determination of quizalofopethyl in tobacco by ultra-performance convergence chromatography with tandem mass spectrometry

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烟草科技 2018年第A1期51卷 38-46页

作者： YANG Fei TANG Gangling FAN Ziyan WANG Ying LIU Shanshan DENG Huimin BIAN Zhaoyang LI Zhonghao Chinn National Tobacco quality Supervision and Test Center No.2 Fengyang Street Zhengzhou 450001 China

The purpose of this study was to develop and validate a novel and sensitive method for simultaneous enantiomeric analysis of quizalofop-ethyl in tobacco using ultra-performance converge nee chromatography with tandem mass spectrometry(UPC-MS/MS).Sample preparation prior to UPC^2-MS/MS analysis followed a QuEChERS(quick,easy,cheap,effective,rugged and safe)*** UPC^2-MS/MS method used an Acquity UPC2 Trefoil CEL2 column with a mobile phase of CO2 and *** injection volume was 2 μL and run-time was 6 min with the mobile phase running at 2.0 mL/min flow *** temperature,auto back pressure regulator pressure(ABPR),and modifier solvent were optimized for separation *** the optimal conditio ns,the recoveries for all the ena ntiomers were 81.3%-94.8% with relative standard deviations(RSD)less than 5.0% at 0.1,1.0 and 2.0 mg/kg levels,*** coefficients of determination(R^2≥0.993 7)were achieved for all the studied enantiomers in the tobacco over the concentration range of 10-250 ng/*** limits of detection(LODs)varied from 0.02 mg/kg to 0.04 mg/kg,and the limits of quantification(LOQs)were ≤ 0.13 mg/*** results confirm that the proposed method is green,convenient and reliable for the enantioselective determination of the enantiomers of quizalofop-ethyl in tobacco.

关键词： Quizalofop-ethyl Stereoselective separation Herbicide Tandem mass spectrometry Ultraperformance convergence chromatography

The Cloud Manufacturing Resource Scheduling Optimization Method Based on Game Theory

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Journal on Artificial Intelligence 2022年第4期4卷 229-243页

作者： Xiaoxuan Yang Zhou Fang heilongjiang Province Cyberspace Research Center Heilongjiang Province Harbin150090China

In order to optimize resource integration and optimal scheduling problems in the cloud manufacturing environment,this paper proposes to use load balancing,service cost and service quality as optimization goals for resource scheduling,however,resource providers have resource utilization requirements for cloud manufacturing *** the process of resource optimization scheduling,the interests of all parties have conflicts of interest,which makes it impossible to obtain better optimization results for resource ***,amultithreaded auto-negotiation method based on the Stackelberg game is proposed to resolve conflicts of interest in the process of resource *** cloud manufacturing platform first calculates the expected value reduction plan for each round of global optimization,using the negotiation algorithm based on the Stackelberg game,the cloud manufacturing platformnegotiates andmediateswith the participants’agents,to maximize self-interest by constantly changing one’s own plan,iteratively find multiple sets of locally optimized negotiation plans and return to the cloud manufacturing *** multiple rounds of negotiation and calculation,we finally get a target expected value reduction plan that takes into account the benefits of the resource provider and the overall benefits of the completion of the manufacturing ***,through experimental simulation and comparative analysis,the validity and rationality of the model are verified.

关键词： Cloud manufacturing resource scheduling optimal allocation of resources conflict of interest stackelberg game

Validation and adaptation of the Physical Activity Enjoyment Scale (PACES) in fitness group exercisers

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Journal of Sport and Health Science 2020年第4期9卷 352-357页

作者： Pedro Teques Luıs Calmeiro Carlos Silva Carla Borrego N2i Polytechnic Institute of Maia Research CentreMaia 4475-690Portugal CIPER Interdisciplinary Centre for the Study of Human PerformanceCruz Quebrada 1499-002Portugal Abertay University School of Social and Health SciencesDundee DD11HGUK Polytechnic Institute of Santarem Sport Sciences School of Rio MaiorSantarem 2001-904Portugal CIEQV—Life quality Research Center Santarem 2001-904Portugal

Background:Recently,Mullen et al.(2011)presented an 8-item version of the Physical Activity Enjoyment Scale(PACES)that provides a valid instrument for assessing enjoyment in physical *** present paper investigated the psychometric properties of a Portuguese adaptation of ***:After a process of back-to-back translation into Portuguese,395 members of fitness centers who ranged in age from 18 to 66 years(31.11§8.90,mean§SD)completed the translated version of the *** average,participants had 3.2 years of experience in fitness group classes and practiced for approximately 3.3 times per ***:An initial exploratory factor analysis(n=139)revealed a unidimensional structure with factor loadings ranging from 0.79 to *** also showed acceptable internal consistency.A confirmatory factor analysis in an independent sample(n=256)provided additional support for the unidimensional structure of the *** addition,moderate positive correlations between enjoyment and intrinsic and identified regulation,and moderate negative correlations between enjoyment and external and amotivation,demonstrate the convergent validity of the ***,measurement invariance between 2 independent samples was also ***:The 8-item Portuguese version of PACES is a valid and reliable instrument for measuring enjoyment of physical activity in Portuguese adult fitness exercisers,and it is therefore suitable to use as a measure of affect in exercise adherence interventions studies.

关键词： Confirmatory factor analysis Construct validity Enjoyment Exploratory factor analysis Fitness Measurement invariance Self-determination theory

The Application of Analytic Hierarchy Process Method in the Evaluation of Educational quality in Colleges and Universities

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Journal of Contemporary Educational Research 2024年第7期8卷 335-342页

作者： Junbo Lei Yanxia Xu Junpeng Wang School of Foreign Languages Heilongjiang University of Business and TechnologyHarbin 150025Heilongjiang ProvinceChina School of Foreign Language Harbin Cambridge UniversityHarbin 150086Heilongjiang ProvinceChina English Department Heilongjiang International UniversityHarbin 150500Heilongjiang ProvinceChina

Talent quality is the lifeline of colleges and *** on employment guidance,this paper establishes a student quality evaluation and control system including knowledge,moral character,and ability,and uses the Analytic Hierarchy Process(AHP)method to analyze the factors affecting the quality of education in colleges and *** addition,some suggestions are provided to improve the quality of students.

关键词： Student quality Knowledge Ability Literacy

determination of okadaic acid related toxins from shellfish (<i>sinonovacula constricta</i>) by high performance liquid chromatography tandem mass spectrometry

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Agricultural Sciences 2013年第5期4卷 1-6页

作者： Hai-qi Zhang Weicheng Liu Xin He Li-jun Liang Wenyong Ding Zhong-yang He 1Zhejiang Fisheries quality Testing centre Hangzhou China 2College of life science Zhejiang University Hangzhou China College of Food Science and Biotechnology Engineering Zhejiang Gongshang University Hangzhou China Zhejiang Fisheries quality Testing centre Hangzhou China Zhejiang Mariculture Research Institute Wenzhou China

Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). It was therefore essential that there are analytical techniques to identify and quantify DSP toxins in shellfish. This new methodology could facilitate DSP monitoring and create a means of rapidly responding to incidents threatening public health. In the last years there were different analytical methods for DSP, such as mouse bioassay and LC-FLD. With the development of instrument, Liquid chromatography-mass spectrometry was substituted for other analytical methods with its good sensitivity and selectivity and without derivatization for the determination of DSP. In this report, a high performance liquid chromatogra-phytandem mass spectrometric(HPLC-MS/MS)method was developed for the simultaneous determination of okadaic acid (OA) and dinophysistoxins(DTX1) in Sinonovacula constricta. Optimization of pretreatment experiment was carried out to maximize recoveries and the effectiveness. The analytes were determined under multi-reactions monitoring (MRM) scan type with tandem mass analyzer using negative ion electrospray ionization (-ESI) mode .Finally, the detection and identification of OA and DTX-1 were based upon their retention times (RT) and the fragmentation patterns of their mass spectra. The method of LOQ for the two poisons was 0.02 mg·*** real sample test showed that this method could be used for sensitive, fast, and accurate determination of the two diarrheic shellfish poisons in shellfish.

关键词： Sinonovacula Constricta High Performance Liquid Chromatography-Tandem Mass Spectrometry Okadaic Acid Dinophysistoxins-1

Thoughts on Promoting High-quality Employment of Students Based on School-Enterprise Cooperation

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Journal of Contemporary Educational Research 2020年第6期4卷 64-68页

作者： Yanchao Wang heilongjiang Bayi Agricultural University Daqing 163319Heilongjiang ProvinceChina

The effective operation of school-enterprise cooperation is of great strategic significance to promote college students to achieve employment of ***,this paper will make a detailed discussion on the effect that school-enterprise cooperation accelerates college students to achieve employment in good quality,hoping that it can provide the necessary guidance information to the researchers in this field.

关键词： School-enterprise cooperation Promotion Employment in good quality of students

Small-molecule 7,8-dihydroxyflavone counteracts compensated and decompensated cardiac hypertrophy via AMPK activation

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Journal of Geriatric Cardiology 2022年第11期19卷 853-866页

作者： Peng-Zhou HANG Pei-Feng LI Jie LIU Feng-Feng LI Ting-Ting CHEN Yang PAN Man-Ru ZHANG Hua-Qing YU Hong-Yu JI Zhi-Min DU Jing ZHAO Institute of Clinical Pharmacology the Second Affiliated Hospital of Harbin Medical University(University Key Laboratory of Drug ResearchHeilongjiang Province)HarbinChina Department of Pharmacy Clinical Medical CollegeYangzhou UniversityNorthern Jiangsu People's HospitalYangzhouChina Department of Pharmacology Harbin Medical UniversityHarbinChina State Key Laboratory of quality Research in Chinese Medicines Macao University of Science and TechnologyMacaoChina Department of Cardiology the First Affiliated Hospital of Harbin Medical UniversityHarbinChina

BACKGROUND Pathological cardiac hypertrophy is a compensated response to various stimuli and is considered a key risk factor for heart failure.7,8-Dihydroxyflavone(7,8-DHF)is a flavonoid derivative that acts as a small-molecule brain-derived neurotrophic factor *** present study aimed to explore the potential role of 7,8-DHF in cardiac *** Kunming mice and H9c2 cells were exposed to transverse aortic constriction or isoproterenol(ISO)with or without 7,8-DHF,respectively.F-actin staining was performed to calculate the cell *** levels of hypertrophic markers,including ANP,BNP,andβ-MHC,were ***,hematoxylin-eosin staining,and transmission electron microscopy were used to examine the cardiac function,histology,and ultrastructure of *** levels of mitochondria-related factors,such as adenosine monophosphate-activated protein kinase(AMPK),and peroxisome proliferator-activated receptorγcoactivator-1α(PGC-1α),were *** 7,8-DHF inhibited compensated and decompensated cardiac hypertrophy,diminished the cross-sectional area,and alleviated the mitochondrial disorders of ***,7,8-DHF reduced the cell size and repressed the mRNA levels of the hypertrophic markers of ISO-treated *** addition,7,8-DHF activated AMPK and PGC-1αsignals without affecting the protein levels of mitochondrial dynamics-related *** effects of 7,8-DHF were eliminanted by Compound C,an AMPK *** These findings suggest that 7,8-DHF inhibited cardiac hypertrophy and mitochondrial dysfunction by activating AMPK signaling,providing a potential agent for the treatment of pathological cardiac hypertrophy.

关键词： cardiac hypertrophy inhibited