scholarly journals A method for determining the content of petroleum hydrocarbons in soil

2021 ◽  
Vol 9 (03) ◽  
pp. 40-55
Author(s):  
Haitian Qin ◽  
He Huang
Keyword(s):  
Petroleum Hydrocarbons ◽  
Extraction Efficiency ◽  
Ultrasonic Power ◽  
Optimal Conditions ◽  
Relative Standard ◽  
Ultrasonic Time ◽  
Standard Deviations ◽  
Centrifugal Extraction ◽  
Extraction Agent

In this paper, ultrasonic - centrifugal extraction - infrared oil meter is used to determine petroleum hydrocarbons in soil.The optimal conditions of ultrasonic centrifugal extraction of petroleum hydrocarbons from soil were investigated by using simulated soil from the extraction agent, ultrasonic temperature, ultrasonic time, ultrasonic power, centrifugal speed, centrifugal time and other factors.The results showed that using tetrachloroethylene as extraction agent, the extraction efficiency of three times reached 88.34% with ultrasonic temperature of 30℃, ultrasonic time of 10min, ultrasonic power of 180W, centrifugal speed of 4000rpm and centrifugation time of 20min in 1% oil-contaminated soil.Under these conditions, the recoveries were 78.97%~96.58% and the relative standard deviations (n=5) of the measured values were 3.82%~12.53%.

Optimization for the Process of Chlorophyll a Extraction by Orthogonal Method

2014 ◽  
Vol 1051 ◽  
pp. 423-427
Author(s):  
Jun Sen Wu ◽  
Chen Chen Liu ◽  
Bing Li ◽  
Xiu Zhi Wan
Keyword(s):  
Chlorophyll A ◽  
Orthogonal Experiment ◽  
Ultrasonic Power ◽  
Assisted Extraction ◽  
Ultrasonic Time ◽  
Ultrasonic Assisted ◽  
Ultrasonic Assisted Extraction ◽  
Extraction Agent ◽  
Optimum Extraction ◽  
Single Factor Experiment

The 90% acetone as extraction agent used in order to obtain the ultrasonic assisted extraction conditions of chlorophyll a. The ultrasonic power, ultrasonic time, centrifugation time and rotational speed as the four study factors and the chlorophyll a concentration as the target, here, the L9(34) orthogonal table of orthogonal experiment design are used in order to determine the optimum extraction contractions, basing on the single factor experiment. The experimental results shows the algae containing water can get better extraction effect, after ultrasonic 30 minutes in 225W and 6000r/min speed centrifugal 9 minutes and then mixing, repeat ultrasound centrifugation steps.

Ultrasound-Assisted Emulsification Microextraction-Solvent Floating Solidification-Pre-Column Derivatization for the Determination of Estrogens in Water Samples

2013 ◽  
Vol 663 ◽  
pp. 899-904 ◽  
Author(s):  
Yu Li ◽  
Chen Zhang ◽  
Chong Meng ◽  
Chang Zhi Zhou
Keyword(s):  
Water Samples ◽  
Correlation Coefficients ◽  
Tween 20 ◽  
Ultrasonic Power ◽  
Real Water Samples ◽  
Surface Plot ◽  
Relative Standard ◽  
Ultrasonic Time ◽  
Ultrasound Assisted ◽  
Emulsification Microextraction

The method of ultrasound-assisted surfactant-enhanced emulsification microextraction combined with pre-column derivatization (UAE-SEEME-SFO-PD) was developed to simultaneously extract and determine the estrogens such as estriol (E3), bisphenol A (BPA), 17α-Ethynylestradiol (EE2), estradiol (E2) and nonylphenol (NP) in water samples. Central composite design was employed to investigate the effects of the factors, including emulsifier (Tween 20) volume, extractant (dodecanol) volume, ultrasonic power, ultrasonic time, the amount of derivating agent (paranitrobenzoyl chloride), temperature of derivatization and derivatization time, on the response of analytes. The optimized analytical conditions were obtained by response surface plot as follows: 40 µL of Tween 20, 35 µL of dodecanol, 62.5 W of ultrasonic power, 15 min of ultrasonic time, 5.0 mg of derivating agent, temperature of derivatization 35 °C and derivatization time 2.0 min, with the linear range of 0.02-2.0 mg/L for E3, BPA, EE2 and E2, 0.02-1.0 mg/L for NP, respectively (the correlation coefficients ranging from 0.9950 to 0.9999). Also, the limits of detection were found between 1.06-5.04 µg/L. The spiked recoveries of estrogens under different spiked levels (0.02, 0.20 and 1.00 mg/L) for estrogens were in the range of 88.08-117.33%, and the relative standard deviation (RSD) was of 0.75-9.73%. Additionally, the method could be applied to analysis of estrogens in real water samples (collected from upstream and downstream of a reservoir), and the relative recoveries of estrogens under spiked levels (0.05 and 0.50 mg/L) for estrogens in real water samples were in the range of 85.18-124.17% (RSD 0.30-10.71%).

scholarly journals Ultrasonic-Assisted Extraction of Procyanidins Using Ionic Liquid Solution fromLarix gmeliniiBark

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Xiaowei Sun ◽  
Zhimin Jin ◽  
Lei Yang ◽  
Jingwei Hao ◽  
Yuangang Zu ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Extraction Efficiency ◽  
Liquid Solution ◽  
Extraction Process ◽  
Ultrasonic Power ◽  
Assisted Extraction ◽  
Ultrasonic Time ◽  
Ultrasonic Assisted ◽  
Ultrasonic Assisted Extraction

An ionic liquid-based ultrasonic-assisted extraction method has been developed for the effective extraction of procyanidins fromLarix gmeliniibark. So as to evaluate the performance of ionic liquids in ultrasonic-assisted extraction process, the effects caused by changes in the anion and the alkyl chain length of the cation on the extraction efficiency were investigated in this paper. The results indicated that the characteristics of anions had remarkable effects on the extraction efficiency of procyanidins, and 1-butyl-3-methylimidazolium bromide ([Bmim]Br) aqueous solution was the best among the investigated ionic liquids. The optimum conditions for the extraction were as follows: [Bmim]Br concentration 1.25 M, soak time 3 h, solid-liquid ratio 1 : 10, ultrasonic power 150 W, and ultrasonic time 30 min. This work not only introduces a simple, green, and highly efficient sample preparation method for extraction of procyanidins fromL. gmeliniibark, but also reveals the tremendous application potential of ionic liquids.

Study on Method of Extraction and Determination of Cucurbitin

2014 ◽  
Vol 881-883 ◽  
pp. 823-826
Author(s):  
Ying Wang ◽  
Qin Chao Ma ◽  
Hao Nan Xu ◽  
Kun Feng ◽  
Yan Tang
Keyword(s):  
Liquid Chromatography ◽  
Standard Deviation ◽  
Dilute Hydrochloric Acid ◽  
Ultrasonic Power ◽  
Pumpkin Seed ◽  
Extraction Solvent ◽  
Relative Standard ◽  
Ultrasonic Time ◽  
Method Of Extraction

Cucurbitin is a kind of specific alkaloids in pumpkin seed. The extraction conditions of cucurbitin were optimized as: extraction solvent was 4% dilute hydrochloric acid, rate of material to solvent was 1:20, ultrasonic power was 200 w and ultrasonic time was 75 min. The content of cucurbitin in pumpkin seed was determined by liquid chromatography. The linear between concentration and peak area were good within 160 μg mL-1. The recoveries were 96.50%~102.1%. The relative standard deviation was 1.08%. The results are accurate, true and reliable.

scholarly journals Quantitative Detection of Chromium Pollution in Biochar Based on Matrix Effect Classification Regression Model

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2069
Author(s):  
Mei Guo ◽  
Rongguang Zhu ◽  
Lixin Zhang ◽  
Ruoyu Zhang ◽  
Guangqun Huang ◽  
...  
Keyword(s):  
Regression Model ◽  
Matrix Effect ◽  
Nearest Neighbor ◽  
Quantitative Detection ◽  
Least Squares Regression ◽  
K Nearest Neighbor ◽  
Breakdown Spectroscopy ◽  
Relative Standard ◽  
Calibration Samples ◽  
Standard Deviations

Returning biochar to farmland has become one of the nationally promoted technologies for soil remediation and improvement in China. Rapid detection of heavy metals in biochar derived from varied materials can provide a guarantee for contaminated soil, avoiding secondary pollution. This work aims first to apply laser-induced breakdown spectroscopy (LIBS) for the quantitative detection of Cr in biochar. Learning from the principles of traditional matrix effect correction methods, calibration samples were divided into 1–3 classifications by an unsupervised hierarchical clustering method based on the main elemental LIBS data in biochar. The prediction samples were then divided into diverse classifications of calibration samples by a supervised K-nearest neighbor (KNN) algorithm. By comparing the effects of multiple partial least squares regression (PLSR) models, the results show that larger numbered classifications have a lower averaged relative standard deviations of cross-validation (ARSDCV) value, signifying a better calibration performance. Therefore, the 3 classification regression model was employed in this study, which had a better prediction performance with a lower averaged relative standard deviations of prediction (ARSDP) value of 8.13%, in comparison with our previous research and related literature results. The LIBS technology combined with matrix effect classification regression model can weaken the influence of the complex matrix effect of biochar and achieve accurate quantification of contaminated metal Cr in biochar.

scholarly journals Optimization of Ultrasonic-Assisted Extraction, Characterization, and Antioxidant Activities of Polysaccharides From Sojae Semen Praeparatum

2021 ◽  
Vol 16 (5) ◽  
pp. 1934578X2110206
Author(s):  
Yongshuai Jing ◽  
Ruijuan Zhang ◽  
Lan Li ◽  
Danshen Zhang ◽  
Yu Liu ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Deae Cellulose ◽  
Chemical Compositions ◽  
Hydroxyl Groups ◽  
Ultrasonic Frequency ◽  
Ultrasonic Power ◽  
Assisted Extraction ◽  
Ultrasonic Time ◽  
Ultrasonic Assisted ◽  
Ultrasonic Assisted Extraction

In this study, response surface methodology (RSM) was used to optimize the ultrasonic-assisted extraction parameters of Sojae Semen Praeparatum polysaccharides (SSPP-80), the optimum conditions were determined as follows: ultrasonic frequency of 100 W, ultrasonic power of 80 Hz, ultrasonic temperature of 52℃, ultrasonic time of 23 minutes, and liquid to raw material ratio of 40 mL/g. Based on these conditions, polysaccharides extraction rate was 7.72% ± 0.26%. Then, 2 novel polysaccharides (SSPP-80‐1, SSPP-80‐2) were isolated from SSPP by DEAE-cellulose 52 chromatography. The chemical compositions, physicochemical properties, and structure of SSPPs were investigated by simultaneous thermal analyzer (TGA), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FI-IR), and high-performance liquid chromatography (HPLC). The results showed that SSPP-80 and 2 fractions were mainly composed of mannose (Man), glucose (Glc), galactose (Gal), xylose (Xyl), and arabinose (Ara). In addition, the antioxidant activities were evaluated against the DPPH and hydroxyl radical in vitro, the IC50 of SSPP-80, SSPP-80‐1 and SSPP-80‐2 against DPPH free radical were 4.407, 8.267, and 5.204 mg/mL, respectively, whereas the IC50values for removing hydroxyl groups were 5.318, 3.516, and 4.016 mg/mL, respectively. It demonstrated that SSPP-80 and 2 fractions had certain antioxidant activity. Theoretical basis for use of Sojae Semen Praeparatum polysaccharides was provided by this study.

Process Optimization of the Preparation of TiO2 Microcapsule Used for Photo-Catalytic Degradation with Ultrasound Irradiation

2012 ◽  
Vol 627 ◽  
pp. 770-774
Author(s):  
Xiao Mei Wang ◽  
Bao Bao Zhao ◽  
Cheng Rong Zhang
Keyword(s):  
Process Optimization ◽  
Ultrasound Irradiation ◽  
Core Material ◽  
Wall Material ◽  
Ultrasonic Power ◽  
Complex Coacervation ◽  
Photo Degradation ◽  
Reaction Solution ◽  
Ultrasonic Time ◽  
Ultrasonic Conditions

Microcapsules were prepared using the complex coacervation method with nano anatase TiO2 as the core material, gelatin/Arabia gum as the wall material, while dispersing TiO2 into the reaction solution using the ultrasonic. The prepared microcapsules can be finished into textiles such as the polypropylene nonwovens, and the microcapsules in the textiles gradually fracture and the anatase TiO2 was released, which would facilitate photo-degradation of the polypropylene nonwovens when exposed in sunlight. The microcapsules size was used as the process optimization evaluation index, and the quadratic general revolving combination design was used to conduct the experiments for obtaining the optimum ultrasonic conditions, and the other progress parameters were the same that used in our early microcapsule preparation. The obtained optimal process for ultrasound is: ultrasonic time is 17min; ultrasonic power is 74W and ultrasound temperature 60 °C.

scholarly journals Simultaneous Determination of Nitroimidazoles and Quinolones in Honey by Modified QuEChERS and LC-MS/MS Analysis

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Haiyan Lei ◽  
Jianbo Guo ◽  
Zhuo Lv ◽  
Xiaohong Zhu ◽  
Xiaofeng Xue ◽  
...  
Keyword(s):  
Recovery Rates ◽  
Inhibition Effect ◽  
Standard Curve ◽  
Modified Quechers ◽  
Relative Standard ◽  
Acacia Honey ◽  
The Matrix ◽  
Liquid Chromatography Tandem Mass ◽  
Standard Deviations

This study reports an analytical method for the determination of nitroimidazole and quinolones in honey using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A modified QuEChERS methodology was used to extract the analytes and determine veterinary drugs in honey by LC-MS/MS. The linear regression was excellent at the concentration levels of 1–100 ng/mL in the solution standard curve and the matrix standard curve. The recovery rates of nitroimidazole and quinolones were 4.4% to 59.1% and 9.8% to 46.2% with relative standard deviations (RSDs) below 5.2% and the recovery rates of nitroimidazole and quinolones by the matrix standard curve ranged from 82.0% to 117.8% and 79% to 115.9% with relative standard deviations (RSDs) lower than 6.3% in acacia and jujube honey. The acacia and jujube honeys have stronger matrix inhibition effect to nitroimidazole and quinolones residue; the matrix inhibition effect of jujube honey is stronger than acacia honey. The matrix standard curve can calibrate matrix effect effectively. In this study, the detection method of antibiotics in honey can be applied to the actual sample. The results demonstrated that the modified QuEChERS method combined with LC-MS/MS is a rapid, high, sensitive method for the analysis of nitroimidazoles and quinolones residues in honey.

Optimization of the Ultrasonic Extraction of Gypenoside III from Gynostemma pentaphyllum by Response Surface Methodology

2012 ◽  
Vol 550-553 ◽  
pp. 1866-1870
Author(s):  
Xiao Dan Tang ◽  
Hai Yang Hang ◽  
Shao Yan Wang ◽  
Jing Xiang Cong
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Extraction Yield ◽  
Raw Material ◽  
Extraction Temperature ◽  
Optimal Conditions ◽  
Gynostemma Pentaphyllum ◽  
Bioactive Component ◽  
Yield Value ◽  
Ultrasonic Time

Gypenosides III is a major bioactive component which is rich in Gynostemma pentaphyllum. For better utilization of the native resource, response surface methodology was used to optimize the extraction conditions of gypenosides III from G. pentaphyllum. The effects of three independent variables on the extraction yield of gypenosides III were investigated and the optimal conditions were evaluated by means of Box-Behnken design. The optimal conditions are as follows: ratio of ethanol to raw material 25, extraction temperature 58°C and ultrasonic time 25min. Under these conditions, the yield of gypenoside III is 1.216±0.05%, which is agreed closely with the predicted yield value.

The Dispersion of MWCNTS in Acetone Solution of SAN

2015 ◽  
Vol 1088 ◽  
pp. 8-12
Author(s):  
Xin Long Ling ◽  
Ling Jiao Xie ◽  
Li Ming Zou ◽  
Yi Zhe Wei
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Acetone Solution ◽  
Average Particle ◽  
Ultrasonic Power ◽  
Acrylonitrile Copolymer ◽  
Mass Percent ◽  
Ultrasonic Time ◽  
Styrene Acrylonitrile

MWCNTs were dispersed in acetone solution of styrene-acrylonitrile copolymer (SAN). Four factors which had effect on the average particle size, including the ratio of MWCNTs to SAN, the mass percent of MWCNTs, the ultrasonic power and the ultrasonic time, were studied. The optimal dispersion conditions of MWCNTs in acetone solution of SAN were the ratio of MWCNTs to SAN 1:3, the mass percent of MWCNTs 0.25%, the ultrasonic power 100%, and the ultrasonic time 30 min.

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