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Journal of Environmental Sciences 2011年第10期23卷 1729-1737页

作者： Xun Pan Zhimin Qiang Weiwei Ben Meixue Chen Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This work describes a systematic approach to the development of a method for simultaneous determination of three classes of veterinary antibiotics in the suspended solids （SS） of swine wastewater, including five sulfonamides, three tetracyclines and one macrolide （tiamulin）. The entire procedures for sample pretreatment, ultrasonic extraction （USE）, solid-phase extraction （SPE）, and liquid chromatography-mass spectrometry （LC-MS） quantification were examined and optimized. The recovery efficiencies were found to be 76%-104% for sulfonamides, 81%-112% for tetracyclines, and 51%--64% for tiamulin at three spiking levels. The intra-day and inter-day precisions, as expressed by the relative standard deviation （RSD）, were below 17%. The method detection limits （MDLs） were between 0.14 and 7.14 μg/kg, depending on a specific antibiotic studied. The developed method was applied to field samples collected from three concentrated swine feeding plants located in Beijing, Shanghai and Shandong province of China. All the investigated antibiotics were detected in both SS and liquid phase of swine wastewater, with partition coefficients （logKd） ranging from 0.49 to 2.30. This study demonstrates that the SS can not be ignored when determining the concentrations of antibiotics in swine wastewater.

关键词： antibiotics swine wastewater suspended solids ultrasonic extraction solid-phase extraction mass spectrometry

Rapid Determination of Polar Herbicides in Soil Samples Using Accelerated ultrasonic extraction(AUE) in Combination with Dispersion and In-situ Derivatization

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Journal of Groundwater Science and Engineering 2014年第1期2卷 56-62页

作者： Jian-ye GUI Chen-ling ZHANG Yong-tao ZHANG Li ZHANG Institute of Hydrogeology and Environmental Geology CAGS

An effective novel ultrasonic extraction procedure coupled with gas chromatography and negative chemical ionization mass spectroscopy has been developed for quantitative recovery of polar herbicides in soil. This rapid one-step sample preparation methodology was named accelerated ultrasonic extraction(AUE), and is based on elevated temperatures, increased power and dispersing intimate contact. Simultaneously, in-situ derivatization was achieved by the addition of derivatization reagent, chelating agent and dispersing agent. The extraction efficiency was enhanced by the multiple applied force and elevated ultrasonic temperature. The in-situ derivatization efficiency was enhanced considerably by the use of ultrasonic energy. Dozens of samples can be extracted simultaneously with this method. The sensitivity was improved because of the remarkable reduced background noise achieved using GC-MS in negative chemical ionization(NCI) mode. The amount of reagent and various ultrasonic parameters, such as ultrasonic energy, ultrasonic time and ultrasonic temperature, were optimized. The reproducibility of replicate soil extraction determination of 9 herbicides in different matrix samples and at different concentrations(n=7) was in the range of 4.9-12.6% of the relative standard deviation. The obtained LOD values ranged between 0.02-0.37 μg/kg for all herbicides. Here, we present an improved ultrasonic extraction procedure, which we have termed AUE, can serve as a rigorous high efficiency preparation methodology for polar organic contaminants and can be applied to solid sample pre-treatment extensively.

关键词： ultrasonic extraction Herbicide Polar NCI Soil FLUID extraction ACIDIC HERBICIDE ANALYTES

Determination of 7 Indictor Polychlorinated Biphenyls (PCBs) Residues in Porphyra by ultrasonic extraction and Gas Chromatography (GC)

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Journal of Agricultural Chemistry and Environment 2016年第1期5卷 1-5页

作者： Liangliang Tian Feng Han Youqiong Cai Cong Kong Yongfu Shi Yuan Wang Guangxin Yang Qianyun Zhan Dongmei Huang Aquatic Product Quality Inspection and Test Center (Shanghai) Ministry of Agriculture of China East China Sea Fisheries Research Institute Shanghai China College of Food Science and Engineering Ocean University of China Qingdao China

A method was developed for determination of 7 indictors the polychlorinated biphenyls (PCBs) residues in porphyra by gas chromatography (GC) with electron capture detector (ECD). The PCBs were extracted with hexane/methylene chloride (1:1, v/v) by ultrasonic extraction and the samples were cleaned up by concentrated sulfuric acid and Alumina-N solid phase extraction cartridge. The analytes were quantified by an internal standard method. Under optimal experimental conditions, good linearity was observed in the range of 5 - 200 ng/mL and the correlation coefficients were 0.9994 - 0.9998. The limit of quantitation (LOQ) for target analytes ranged from 6.0 to 10.0 μg/kg. At the spiked levels of 10, 50, 100 μg/kg, the average recoveries ranged from 90.9% to 102% with the relative standard deviations 2.12% - 6.32%. The result showed that the proposed method was rapid, and could be used for the determination of the PCBs in porphyra.

关键词： Polychlorinated Biphenyls (PCBs) Porphyra ultrasonic extraction Gas Chromatography (GC)

Optimization of ultrasonic extraction Process of Total Flavonoids from Mulberry Leaves by Orthogonal Experiment

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Agricultural Biotechnology 2014年第4期3卷 12-13页

作者： Xianling WANG Yaning WANG Xiuxiu YANG Min XU School of Pharmacy Henan University of Traditional Chinese Medicine

In this study, by using mulberry leaves as raw materials, ultrasonic extraction process of total flavonoids from mulberry leaves was optimized by orthogonal experiment. Results showed that the maximum yield of total flavonoids （6.1% ） was obtained from mulberry leaves with addition of 45 times the volume of water by ultrasonic extraction at 55 ℃ for three times, 55 min each. According to the verification test, the optimized technical process was reasonable and feasible with high stability.

关键词： Orthogonal experiment Mulberry leaves Total flavonoids ultrasonic extraction

Study on ultrasonic extraction of Total Flavonoids from Angelica keiskei Koidzumi

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Agricultural Biotechnology 2016年第3期5卷 6-8页

作者： Yaoming HU Donghai CHU School of Biological Medicine and Chemical Engineering Liaoning Institute of Science and Technology

[Objective] This study aimed to optimize the ultrasonic extraction process of total flavonoids from Angelica keiskei Koidzumi. [Method] Using the yield of total flavonoids as an indicator, the ultrasonic extraction process of total flavonoids from A. keiskei was optimized by orthogonal experimental design. [ Result ] Among four factors in orthogonal experimental design, extraction time exhibited the most significant effect on the extraction result; ethanol concentration exhib- ited a significant effect on the extraction result; ultrasonic power and solid-to-liquid ratio had no significant effect. The optimal conditions for ultrasonic extraction of total flavonoids from A. keiskei were extraction time of 25 min, ethanol concentration of 80%, ultrasonic power of 60 W, solid-to-liquid ratio of 1：20 （g/ml）, under which the yield of total flavonoids reached 1.56%. [ Conclusion] This study provides the basis for further development and utilization of total flavonoids from A. keiskei.

关键词： Angelica keiskei Koidzumi Total flavonoids Orthogonal experiment ultrasonic extraction

Aqueous Two-phase Systems with ultrasonic extraction Used for Extracting Phenolic Compounds from Inonotus obliquus

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Chinese Herbal Medicines 2013年第1期5卷 67-72页

作者： ZHAO Yan-xia LIU Yu-bing LIU Feng ZHENG Wei-fa Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province Jiangsu Normal University

Objective To optimize the extracting technology of assessing the maximum yield of phenolic compounds (PC) from Inonotus obliquus by single factor experiments and orthogonal array design methods through aqueous two-phase systems combined with ultrasonic extraction. Methods The range of the independent variables, namely levels of acetone and ammonium sulfate, and ultrasonic time were identified by a first set of single factor experiments. The actual values of the independent variables coded at four levels and three factors were selected based on the results of the single factor experiments. Subsequently, the levels of acetone and ammonium sulfate, and ultrasonic time were optimized using the orthogonal array method. Results The optimum conditions for the extraction of PC were found to use 7.0 mL acetone, 5.5 mg ammonium sulfate, with ultrasonic time for 5 min. Under these optimized conditions, the experimental maximum yield of PC was 37.8 mg/g, much higher than that of the traditional ultrasonic extraction (UE, 29.0 mg/g). And the PC obtained by this method had stronger anti-oxidative activities than those by traditional UE method. Conclusion These results indicate the suitability of the models developed and the success in optimizing the extraction conditions. This is an economical and efficient method for extracting polyphenols from I. obliquus.

关键词： aqueous two-phase systems free radicals Inonotus obliquus phenolic compounds ultrasonic extraction

Optimization of ultrasonic extraction Process of Polysaccharides from Polyporus umbellatus

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Agricultural Biotechnology 2015年第6期4卷 7-9页

作者： Juanjuan DU Mengting LIU Fei LI College of Chemical and Biochemical Engineering Nanjing Normal University Taizhou College

[ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbellatus. [ Method ] By single-factor experiment, the ultrasonic extraction process of polyperus pelysac- charides was optimized. [Result] The optimal conditions for ultrasonic extraction of polysaccharides from P. umbeUatus were： solid-liquid ratio 1：40 （g： ml）, ex- traction duration 60 rain, extraction temperature 70 ℃, ultrasonic power 100 W. [ Conclusion] Compared with conventional water extraction method, ultrasonic ex- traction could significantly improve the content of polyporus polysaccharides with shorter extraction duration, lower solid-liquid ratio and lower extraction tempera-

关键词： Polyporus umbellatus Polysaccharides ultrasonic extraction Single-factor experiment

Determination of levoglucosan and its two isomers in atmospheric particles by ultrasonic extraction coupled with ultra-high performance liquid chromatography-tandem mass spectrometry

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Determination of levoglucosan and its two isomers in atmosph...

The Optimization of ultrasonic extraction Technology of Total Flavonoids in Leaves of Mallotus apelta by Response Surface Analysis Methodology

中国化学会第十九届全国有机分析及生物分析学术研讨会

作者：赵起越 Hong-Huai Zhao Bao-Xian Liu Yan Wang Han-Cheng Yuan 北京市环境保护监测中心 Beijing Municipal Environmental Monitoring Center

＜正＞Levoglucosan and its isomers----mannosan and galactosan are monosaccharide anhydrides（MAs）from pyrolysis of celluloses and semi-celluloses in high *** are easy to adsorb on atmospheric particles,affecting visi... 详细信息

关键词： UPLC-MS/MS Atmospheric particles ultrasonic extraction Levoglucosan Isomers

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Medicinal Plant 2018年第4期9卷 68-72页

作者： Dengfeng ZOU Ruifen FAN Xiao HUANG Aize XIE Guilin Medical University The First Affiliated Hospital of Guangxi Medical University

[Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assisted ethanol extraction,and extraction rate of total flavonoids was taken as evaluation index. On the basis of single-factor experiment,Box-Behnken response surface methodology was employed for selecting the optimum extraction process. [Results]The optimum extraction conditions of total flavonoids were as follows: 75% of ethanol concentration,1∶ 25 of ratio of material to liquid,31 min of ultrasonic time. Under these conditions,the extraction rate of total flavonoids was 1. 115%.[Conclusions] The extraction process obtained by response surface methodology was stable,reasonable,accurate and reliable. It was a feasible method to extract the total flavonoids from M. apelta leaves.

关键词： Mallotus apelta Total flavonoids ultrasonic extraction Response surface methodology

ultrasonic-Assisted extraction of Puerarin Optimized by Response Surface Methodology

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Ultrasonic-Assisted Extraction of Puerarin Optimized by Resp...