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Fast determination of multi-mycotoxins in corn by dispersive solid-phase extraction coupled with ultra-performance liquid chromatography with tandem quadrupole time-of-flight mass spectrometry

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Journal of Integrative Agriculture 2016年第7期15卷 1656-1666页

作者： WANG Yan DONG Yan-jie LI Zeng-mei DENG Li-gang GUO Chang-ying ZHANG Shu-qiu LI Da-peng ZHAO Shan-cang institute of agricultural quality standards and testing technology Research Shandong Academy of Agricultural SciencesJinan 250100P.R.China Academy of Food Science and Engineering Shandong Agricultural UniversityTai'an 271018P.R.China

A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins （B1, B2, G1, and G2）, fumonisins （B1, B2 and B3）, zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-lfight mass spectrometry （UPLC-Q-TOF-MS） was developed and validated. Samples were extracted with acetonitrile-water （84：16, v：v, containing 1% acetic acid） using ultrasonic extraction. The extracts were puriifed with a dispersive SPE method using C18 as a cleaning agent. The ifnal clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water （5：5, v：v）. The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation （RSD） ranged from 0.18 to 6.29%. Limits of detections ranged from 0.05 to 50 μg kg？1, and limits of quantiifcation ranged from 0.1 to 200 μg kg？1, which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, alfatoxins B1 and fumonisins B1, B2 and B3 were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×104, 0–6.94×103 and 0–3.05×103 μg kg–1, respectively.

关键词： C18 corn mycotoxins dispersive solid-phase extraction

In situ and on-line monitoring of cadmium in soil pore water using an automatic sampling integrated electrochemical sensor

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Science China(Technological Sciences) 2024年第9期67卷 2894-2904页

作者： KUANG JiaJie WEN JunLin CAI XiXi ZHOU LiHua YUAN Yong Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control School of Environmental Science and EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China

Cadmium(Cd) contamination in soil pore water is the primary pathway for Cd uptake by food crops,such as rice(Oryza sativa L.),posing significant risks to both food safety and human *** study presents a novel soil pore water metal sensor(SPW-Msensor) for in situ and online monitoring of Cd in soil pore water(Cd_(pw)).The SPW-Msensor integrates an automated sampling device,comprising a Rhizon sampler and a reciprocating series pump with an independent dual plunger drive,along with a portable electrochemical sensor consisting of a screen-printed electrode,flow cell,and portable *** SPW-Msensor enables the detection of Cd within a linear range of 50 to 300 ppb while exhibiting high anti-interference ***,it demonstrates excellent repeatability(relative standard deviation values(RSDs)standard ICP-MS method(RSDsquality score(Q^(2)) of 0.69,adjusted R^(2) of 0.9345,and root mean square error(RMSE) of *** SPW-Msensor demonstrates real-time monitoring capabilities for assessing Cd levels in acidified *** SPW-Msensor offers an efficient approach for in-situ and continuous monitoring of Cd_(pw)that provides valuable insights applicable to environmental and agricultural domains.

关键词： cadmium pore water electrochemical sensor in-situ monitoring soil

Ultra-highly sensitive dual gases detection based on photoacoustic spectroscopy by exploiting a long-wave,high-power,wide-tunable,singlelongitudinal-mode solid-state laser

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Light(Science & Applications) 2024年第5期13卷 941-956页

作者： Shunda Qiao Ying He Haiyue Sun Pietro Patimisco Angelo Sampaolo Vincenzo Spagnolo Yufei Ma National Key Laboratory of Laser Spatial Information Harbin Institute of TechnologyHarbinChina PolySense Lab Dipartimento Interateneo di FisicaUniversity and Politecnico of BariVia AmendolaBariItaly

Photoacoustic spectroscopy(PAS)as a highly sensitive and selective trace gas detection technique has extremely broad application in many ***,the laser sources currently used in PAS limit the sensing *** to diode laser and quantum cascade laser,the solid-state laser has the merits of high optical power,excellent beam quality,and wide tuning *** we present a long-wave,high-power,wide-tunable,singlelongitudinal-mode solid-state laser used as light source in a PAS sensor for trace gas *** self-built solid-state laser had an emission wavelength of~2μm with Tm:YAP crystal as the gain material,with an excellent wavelength and optical power stability as well as a high beam *** wide wavelength tuning range of 9.44 nm covers the absorption spectra of water and ammonia,with a maximum optical power of~130 mW,allowing dual gas detection with a single laser *** solid-state laser was used as light source in three different photoacoustic detection techniques:standard PAS with microphone,and external-and intra-cavity quartz-enhanced photoacoustic spectroscopy(QEPAS),proving that solid-state laser is an attractive excitation source in photoacoustic spectroscopy.

关键词： power tunable tuning

Determination of Amantadine Residue in Honey by Solid-phase Extraction and High-performance Liquid Chromatography with Pre-column Derivatization and Fluorometric Detection

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Chinese Journal of Chemistry 2011年第8期29卷 1764-1768页

作者：张金振赵静周金慧薛晓峰李熠吴黎明陈芳 Bee Products quality Supervision and testing Center Institute of Apicultural Research Chinese Academy of Agricultural Sciences Beijing 100093 China

Amantadine （AMA） is an anti-viral drug used in apiculture to protect honeybee against the sacbrood virus （Morator aetatulae）. This study described a reliable high-performance liquid chromatographic （HPLC） method for analyzing AMA in honey using a solid-phase extraction （SPE） cartridge （Plexa PCX） for purification, 4-fluoro-7- nitro-2,1,3-benzoxadiazole （NBD-F） as a pre-column derivatization agent, and fluorometric detection （λex =470 nm, λem=530 nm）. The chromatographic separation was performed on an XDB C18 column （150×4.6 mm i.d.） using 0.1% trifluoroacetic acid/acetonitrile （35 ; 65, V/V） as the mobile phase at a flow rate of 1.0 mLomin 1 with a run time of 20 min. Under these optimal conditions, a linear relationship was observed in the range of 0.025--1.0μg·mL-1 with a good correlation coefficient （0.998） and low limit of detection （0.0080 μg·g-1）, the recoveries were all above 90%, and the intra-day and inter-day precision （RSD） ranged from 3.4%--5.1%.

关键词： amantadine honey solid-phase extraction high-performance liquid chromatographic (HPLC),fluorometric detection

Load on Bicycle Frame During Cycling with Different Speeds and Gestures

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Transactions of tianjin University 2011年第4期17卷 270-274页

作者：项忠霞田冠许文关新于晓然 School of Mechanical Engineering Tianjin University tianjin Product quality Inspection technology Research institute

Experiment and dynamic simulation were combined to obtain the loads on bicycle frame. A dynamic model of body-bicycle system was built in ADAMS. Then the body gestures under different riding conditions were captured by a motion analysis system. Dynamic simulation was carried out after the data of body motions were input into the simulation system in ADAMS and a series of loads that the body applied on head tube, seat pillar and bottom bracket were obtained. The results show that the loads on flame and their distribution are apparently different under various riding conditions. Finally, finite element analysis was done in ANSYS, which showed that the stress and its distribution on frame were apparently different when the flame was loaded according to the bicycle testing standard and simulation respectively. An efficient way to obtain load on bicycle flame accurately was proposed, which is sig- nificant for the safety of cycling and will also be the basis for the bicycle design of digitalization, lightening and cus- tomization.

关键词： bicycle load of frame gesture capturing dynamic simulation

PAC Addition for MBR Start up in Micro-polluted Water Treatment

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Journal of Harbin institute of technology(New Series) 2015年第3期22卷 40-47页

作者： Quan Zhang Feiyun Sun Wenyi Dong Rubing Han Lei Liu School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin institute of technology Shenzhen Graduate School quality testing Center

In order to improve membrane reactor( MBR) performance for micro-polluted surface water treatment in start-up phase,removals of nitrogen and organic matters especially synthetic organic matters by MBR and a simultaneous application of powdered activated carbon( PAC) with MBR( PAC-MBR) using flat sheet membrane are investigated. The results confirm that MBR treatment can be effective for the removal of organic matters including trace organics. The added PAC can improve contaminant removal efficiency especially in the beginning of operation when MBR cannot effectively remove contaminants and effluent satisfying quality standards is obtained. Moreover,the removal efficiency of target trace synthetic organics is investigated and the removal mechanism is discussed. Biodegradation by microorganism,rejection by filtration of membrane with biofilm and adsorption all contribute to the removal performance. Furthermore,volatile organic compounds can be removed by aeration. The filtration process is confirmed important for natural organic matters( NOM)removal in both MBR and PAC-MBR systems. Combining with PAC,the MBR can remove all fractions of NOM while the single MBR can hardly reduce fulvic or humic acid in water even during the steady operation.

关键词： MBR powdered activated carbon trichloroethylene nitrobenzene trichlorophenol

Deep-learning architecture for PM_(2.5) concentration prediction: A review

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Environmental Science and Ecotechnology 2024年第5期21卷 17-33页

作者： Shiyun Zhou Wei Wang Long Zhu Qi Qiao Yulin Kang institute of Environmental Information Chinese Research Academy of Environmental SciencesBeijing 100012China School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China College of Water Sciences Beijing Normal UniversityBeijing 100875China

Accurately predicting the concentration of fine particulate matter(PM_(2.5))is crucial for evaluating air pollution levels and public *** advancements have seen a significant rise in using deep learning(DL)models for forecasting PM_(2.5) ***,there is a lack of unified and standardized frameworks for assessing the performance of DL-based PM_(2.5) prediction *** we extensively reviewed those DL-based hybrid models for forecasting PM_(2.5) levels according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)*** examined the similarities and differences among various DL models in predicting PM_(2.5) by comparing their complexity and *** categorized PM_(2.5) DL methodologies into seven types based on performance and application conditions,including four types of DL-based models and three types of hybrid learning *** research indicates that established deep learning architectures are commonly used and respected for their ***,many of these models often fall short in terms of innovation and ***,models hybrid with traditional approaches,like deterministic and statistical models,exhibit high interpretability but compromise on accuracy and ***,hybrid DL models,representing the pinnacle of innovation among the studied models,encounter issues with *** introduce a novel three-dimensional evaluation framework,i.e.,Dataset-MethodExperiment standard(DMES)to unify and standardize the evaluation for PM_(2.5) predictions using DL *** review provides a framework for future evaluations of DL-based models,which could inspire researchers to standardize DL model usage in PM_(2.5) prediction and improve the quality of related studies.

关键词： PM_(2.5)concentration prediction Deep-learning based model Bibliometrics analysis Evaluation framework

Analysis of 13 kinds of steroid hormones in raw milk using modified QuEChERS method combined with UPLC-QTOF-MS

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Journal of Integrative Agriculture 2016年第9期15卷 2163-2174页

作者： TAN Xin-tong LI Zeng-mei DENG Li-gang ZHAO Shan-cang WANG Ming-lin Academy of Food Science and Engineering Shandong Agricultural University Tai'an 271018 P.R. China institute of agricultural quality standards and testing technology Research Shandong Academy of Agricultural Sciences Jinan 250100 P.R.China Key Laboratory of Test technology on Food quality and Safety of Shandong Province Jinan 250100 P.R. China

Thirteen kinds of steroid hormones in raw milk（cow, goat and buffalo milk） were analyzed with ultra performance liquid chromatography-quadrupole time of flight mass spectrometry（UPLC-QTOF-MS） after extraction and cleanup with the modified Qu ECh ERS method. These steroid hormones included 17β-estradiol, estriol, estrone, diethylstilbestrol, progesterone, melengestrol acetate, megestrol acetate, chlormadinone acetate, 19-nortestosterone, metandienone, boldenone, epitestosterone, and testosterone. The limits of detection for the raw milk basing on 3 times the signal to noise ratios（S/N=3） was in range of 0.07-0.51 μg kg^–1, and the limits of quantification（basing on S/N=10 method） covered the ranges from 0.23 to 1.7 μg kg^–1. With matrix external standard method, the substances presented recoveries over the range 74.2–99.7%. Qualitative analysis was also done in the mass/mass spectrum（MS/MS） mode and each debris structure of 13 kinds of steroid hormones was achieved. The methodology was then applied in real raw milk samples which were collected in several areas of China and the progesterone was detected with high level.

关键词： UPLC-QTOF-MS raw milk QuEChERS steroid hormones acidic alumina

Overview of quality standardization for Traditional Chinese Medicine

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China standardization 2009年第2期54卷 10-15页

作者： Zhang Yuting Zhang Ying Guo Yongze Liu Lei Shao Hui Li Hui Central Lab of tianjin Academy of agricultural Sciences China tianjin High-standard quality testing Lab China

This paper presentsan overview of the standardizationprocess for TraditionalChinese Medicine (TCM)quality,and reports on the latestresearch *** also highlightsthe roles of quality andmodernization in this standardizat... 详细信息

关键词： TCM quality standard Progress of research Modernization of TCM