scholarly journals Field Dissipation and Storage Stability of Glufosinate Ammonium and Its Metabolites in Soil

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yun Zhang ◽  
Kai Wang ◽  
Junxue Wu ◽  
Hongyan Zhang
Keyword(s):  
Acetic Acid ◽  
Storage Stability ◽  
Correlation Coefficients ◽  
Ammonium Hydroxide ◽  
Soil Samples ◽  
Agricultural Products ◽  
Glufosinate Ammonium ◽  
Relative Standard ◽  
And Storage ◽  
Different Levels

A simple analytical method was developed to measure concentrations of glufosinate ammonium and its metabolites, 3-methylphosphinico-propionic acid (MPP) and 2-methylphosphinico-acetic acid (MPA), in field soil samples. To determine the minimum quantification limit, samples were spiked at different levels (0.1, 0.5, and 1.0 mg/kg). Soil samples were extracted with ammonium hydroxide solution 5% (v/v), concentrated, and reacted with trimethyl orthoacetate (TMOA) in the presence of acetic acid for derivatization. The derivatives were quantified by gas chromatography (GC) using a flame photometric detector (FPD). The linear correlation coefficients of glufosinate ammonium, MPP, and MPA in soil were 0.991, 0.999, and 0.999, respectively. The recoveries of this method for glufosinate ammonium, MPP, and MPA in soil were 77.2–95.5%, 98.3–100.3%, and 99.3–99.6% with relative standard deviations (RSD) of 1.8–4.1%, 0.4–1.4%, and 1.3–2.0%, respectively. Glufosinate ammonium dissipated rapidly in soil to MPA in hours and gradually degraded to MPP. The half-life of glufosinate ammonium degradation in soil was 2.30–2.93 days in an open field. In soil samples stored at −20°C glufosinate ammonium was stable for two months. The results of this study should provide guidance for the safe application of the herbicide glufosinate ammonium to agricultural products and the environment.

scholarly journals UPLC–MS/MS simultaneous determination of methamphetamine, amphetamine, morphine, monoacetylmorphine, ketamine, norketamine, MDMA, and MDA in hair

2020 ◽  
Vol 32 (2) ◽  
pp. 145-148 ◽  
Author(s):  
Siyuan Chen ◽  
Jianshe Ma ◽  
Xianqin Wang ◽  
Peiwu Geng
Keyword(s):  
Simultaneous Determination ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
Correlation Coefficients ◽  
Ammonium Hydroxide ◽  
Ultra Performance Liquid Chromatography ◽  
Acetate Solution ◽  
Hair Samples ◽  
Relative Standard

Hair is a stable specimen and has a longer detection window (from weeks to months) than blood and urine. Through the analysis of hair, the long-term information of the drug use of the identified person could be explored. Our work is to establish an ultra-performance liquid chromatography–tandem mass spectroscopy (UPLC–MS/MS) method for simultaneous determination of methamphetamine, amphetamine, morphine, monoacetylmorphine, ketamine, norketamine, 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyamphetamine (MDA) in hair. Methoxyphenamine was used as an internal standard. The chromatographic separation was performed on a UPLC ethylene bridged hybrid (BEH) C18 (2.1 mm × 50 mm, 1.7 μm) column using a mobile phase of acetonitrile–water with 10 mmol/L ammonium acetate solution which containing 0.05% ammonium hydroxide. The multiple reaction monitoring in positive electrospray ionization was used for quantitative determination. The intra-day and inter-day precisions (relative standard deviation [RSD]) were below 15%. The accuracy ranged between 85.5% and 110.4%, the average recovery rate was above 72.9%, and the matrix effect ranged between 92.7% and 109.2%. Standard curves were in the range of 0.05–5.0 ng/mg, and the correlation coefficients were greater than 0.995. The established UPLC–MS/MS method was applied to analyze the hair samples successfully.

scholarly journals Application of Graphitized Carbon Black to the QuEChERS Method for Pesticide Multiresidue Analysis in Spinach

2009 ◽  
Vol 92 (2) ◽  
pp. 538-547 ◽  
Author(s):  
Li Li ◽  
Wei Li ◽  
Dongmei Qin ◽  
Shuren Jiang ◽  
Fengmao Liu
Keyword(s):  
Carbon Black ◽  
Correlation Coefficients ◽  
Graphitized Carbon Black ◽  
Quechers Method ◽  
Selected Ion Monitoring ◽  
Multiresidue Analysis ◽  
Graphitized Carbon ◽  
Modified Quechers ◽  
Relative Standard ◽  
Different Levels

Abstract A modified QuEChERS method was optimized to determine 66 pesticide residues in spinach using gas chromatography with mass spectrometric detection in selected-ion monitoring mode. Graphitized carbon black (GCB) at different levels (0, 5, 10, 15, 20, and 25 mg) was used to adsorb the pigments in spinach extracts. Best recoveries with less colored extract samples for all pesticides analyzed were obtained in the presence of 10 mg GCB. Under the optimized condition, analyses of spiked samples were performed at 3 different levels. Correlation coefficients, R2, in the linear range tests were better than 0.99. Average recoveries ranged from 66 to 104, with the relative standard deviation below 16. The limits of quantitation ranged from 50 to 250 g/kg.

scholarly journals Asphalt Incorporation with Ethylene Vinyl Acetate (EVA) Copolymer and Natural Rubber (NR) Thermoplastic Vulcanizates (TPVs): Effects of TPV Gel Content on Physical and Rheological Properties

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1397
Author(s):  
Nappaphan Kunanusont ◽  
Boonchai Sangpetngam ◽  
Anongnat Somwangthanaroj
Keyword(s):  
Storage Stability ◽  
Ethylene Vinyl Acetate ◽  
Softening Temperature ◽  
Plastic Waste ◽  
Gel Content ◽  
Modified Asphalt ◽  
C Storage ◽  
Thermoplastic Vulcanizates ◽  
Polymer Modified Asphalt ◽  
And Storage

Plastic waste has been incorporated with asphalt to improve the physical properties of asphalt and alleviate the increasing trend of plastic waste being introduced into the environment. However, plastic waste comes in different types such as thermoplastic or thermoset, which results in varied properties of polymer modified asphalt (PMA). In this work, four thermoplastic vulcanizates (TPVs) were prepared using different peroxide concentrations to produce four formulations of gel content (with varying extent of crosslinked part) in order to imitate the variation of plastic waste. All four TPVs were then mixed with asphalt at 5 wt% thus producing four formulations of PMA, which went through physical, rheological, and storage stability assessments. PMA with higher gel content possessed lower penetration and higher softening temperature, indicating physically harder appearance of PMA. Superpave parameters remained unchanged among different gel content PMA at temperatures of 64, 70, and 76 °C. PMA with any level of gel content had lower Brookfield viscosity than PMA without gel content at a temperature of 135 °C. Higher gel content resulted in shorter storage stability measured with greater different softening temperatures between top and bottom layers of PMA after 5 days of 163 °C storage. This study shows that asphalt with thermoset plastic waste is harder and easier to pave, thus making the non-recycling thermoset plastic waste more useful and friendly to the environment.

scholarly journals Folate in Red Rhapsody Strawberry—Content and Storage Stability.

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 47
Author(s):  
Julius Rami ◽  
Caroline Dumler ◽  
Nadine Weber ◽  
Michael Rychlik ◽  
Gabriele Netzel ◽  
...  
Keyword(s):  
Storage Stability ◽  
Active Form ◽  
Food Composition ◽  
Biologically Active ◽  
Stable Isotope Dilution ◽  
Isotope Dilution Assay ◽  
C Storage ◽  
Vitamin B9 ◽  
Adults And Children ◽  
And Storage

Folate (Vitamin B9) is critical for a range of biological functions in adults and children, including DNA, protein and neurotransmitter synthesis. It is also essential for the healthy development of the fetus in early pregnancy and for the prevention of neural tube defects, such as spina bifida. Strawberries are considered a tasty and healthy fruit consumed all over the world and may potentially be an important dietary source of natural folates. However, the relative importance of strawberry as a dietary source will depend on the total folate concentration, vitamer profile, storage stability and bioavailability to humans. Red Rhapsody, an important commercial strawberry cultivar in Australia, was screened for its folate content and storage stability by stable isotope dilution assay (SIDA). Total folate content ranged from 90–118 μg/100 g fresh weight (fw), which was well above the value in the Australian Food Composition Database (39 μg/100 g fw). 5-Methyltetrahydrofolate, the biologically active form in humans, was the principal vitamer present. Furthermore, folate remained relatively stable during refrigerated (4 °C) storage (loss of only 28% after 14 days of storage). This information is relevant for consumers since the inherent perishability of strawberry fruit makes refrigerated storage common practice in Australian households.

scholarly journals Characterization and storage stability of spray dried soy-rapeseed lecithin/trehalose liposomes loaded with a tilapia viscera hydrolysate

2021 ◽  
pp. 102708
Author(s):  
Cindy T. Sepúlveda ◽  
Ailén Alemán ◽  
José E. Zapata ◽  
M. Pilar Montero ◽  
M. Carmen Gómez-Guillén
Keyword(s):  
Storage Stability ◽  
And Storage ◽  
Spray Dried ◽  
Rapeseed Lecithin

Effect of heat-treated flour on the quality and storage stability of fresh noodles

LWT ◽  
2021 ◽  
pp. 111463
Author(s):  
Tingting Hong ◽  
Qiyan Zhao ◽  
Dan Xu ◽  
Yirong Yuan ◽  
Yue Ma ◽  
...  
Keyword(s):  
Storage Stability ◽  
Heat Treated ◽  
And Storage

Stabilization of water-in-oil emulsion of Pulicaria jaubertii extract by ultrasonication: Fabrication, characterization, and storage stability

2021 ◽  
Vol 350 ◽  
pp. 129249
Author(s):  
Qais Ali Al-Maqtari ◽  
Abduljalil D.S. Ghaleb ◽  
Amer Ali Mahdi ◽  
Waleed Al-Ansi ◽  
Abeer Essam Noman ◽  
...  
Keyword(s):  
Storage Stability ◽  
Oil Emulsion ◽  
Water In Oil Emulsion ◽  
And Storage
Sign in / Sign up

Export Citation Format

Share Document