A liquid chromatographic method is described for the analysis of RH-5992 (N'-t-butyl-N'-[3,5-dimethyl-benzoyl]-N- [-ethylbenzoyl]hydrazine) from various terrestrial and aquatic forestry matrixes and stream water. The processed soils, litter, oak foliage, sediment, aquatic plants, and fish were extracted with a mixture of acetone and water; balsam fir needles were extracted with acidified methanol solution; stream water was extracted with dichloromethane. Aliquots of crude extracts were solvent partitioned, concentrated, and cleaned up by using Florisil or Prepsep-NH2 columns. After fractional elution of the columns with hexane-ethyl acetate as the eluent, the eluates were analyzed on a liquid chromatograph equipped with a diode-array UV detector set at 236 nm, using an RP-8, 10 microns column with a mobile phase of acetonitrile-dioxane-water. Fir needles required methanol in addition to the 3 solvents in the mobile phase mixture. Water samples did not require any column cleanup. Mean recoveries for the analyte ranged from 84 to 98%, with coefficients of variation from 5 to 10%. Limits of detection (LOD) and limits of quantitation (LOQ) ranged from 0.004 to 0.030 ppm and from 0.013 to 0.101 ppm, respectively, for various forestry matrixes. LOD and LOQ for natural waters were 0.050 and 0.166 ppb, respectively.
Download full-text PDF |
Source |
|---|
Publication Analysis
Top Keywords
Similar Publications
Machine Learning Models for Predicting Thermal Properties of Radiative Cooling Aerogels.
Gels
January 2025
School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.
The escalating global climate crisis and energy challenges have made the development of efficient radiative cooling materials increasingly urgent. This study presents a machine-learning-based model for predicting the performance of radiative cooling aerogels (RCAs). The model integrated multiple parameters, including the material composition (matrix material type and proportions), modification design (modifier type and content), optical properties (solar reflectance and infrared emissivity), and environmental factors (solar irradiance and ambient temperature) to achieve accurate cooling performance predictions.
View Article and Find Full Text PDFEngineering active sites on N, S co-doped carbon matrix-encapsulated Ni-modified CoS nanoparticles enabling efficient urea electrooxidation.
J Colloid Interface Sci
January 2025
College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004 PR China.
Interface engineering and electronic modulation enable precise tuning of the electronic structure, thereby maximizing the efficacy of active sites and significantly enhancing the activity and stability of the electrocatalyst. Herein, a hybrid material composed of Ni-modified CoS nanoparticles ((Co, Ni)S) encapsulated within an N, S co-doped carbon matrix (SNC) and anchored onto S-doped carbonized wood fibers (SCWF) is synthesized using a straightforward simultaneous carbonization and sulfidation approach. Density functional theory (DFT) calculations reveal that the highly electronegative Ni element promotes electron cloud migration from Co to Ni, shifting the d-band center of Co closer to the Fermi level.
View Article and Find Full Text PDFDesigning mechanically robust one-component nanocomposites via hyperbranched cellulose nanofibril grafted vegetable oil polymers.
Carbohydr Polym
March 2025
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China; Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry (CAF), No 16, Suojin Wucun, Nanjing, China. Electronic address:
Achieving effective interfacial compatibility between hydrophilic cellulose nanofibrils (CNFs) and hydrophobic vegetable oil polymers (VOPs) remained a significant challenge. To address this issue, we developed a one-component nanocomposite (OCN) based on hyperbranched CNF-grafted VOPs. Rigid precursor initiator poly (vinylbenzyl chloride) (PVBC) was first grafted onto the CNF surface via phase-transfer catalysis, forming a branched macroinitiator (CNF-g-PVBC) with chlorine contents ranging from 4.
View Article and Find Full Text PDFKonjac glucomannan/zein active film loaded with tea polyphenol-ferric nanoparticles for strawberry preservation.
Int J Biol Macromol
January 2025
College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China. Electronic address:
With increasing global environmental awareness and concerns about food safety, biodegradable active packaging has garnered widespread attention. In this study, the stability and bioactivity of tea polyphenol (TP) were enhanced through the preparation of TP-ferric nanoparticles (TP-Fe NPs) using metal-polyphenol ion coordination. Moreover, the introduction of Fe ions can further enhance the antibacterial effects of TP-Fe NPs.
View Article and Find Full Text PDFHeat-stable single-helical structures formed during the extrusion process play a key role in the cooking and texture qualities of rice noodles.
Int J Biol Macromol
January 2025
State Key Laboratory of Food Science and Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang 330047, China; International Institute of Food Innovation Co, Ltd, Nanchang University, Nanchang 330200, China. Electronic address:
Extrusion is a critical process in rice noodle production. However, the underlying mechanism by which it influences noodle quality remains inadequately understood. In this study, rice noodles were processed at extrusion temperatures ranging from 100 °C to 140 °C and characterized in terms of molecular structure, short- and long-range order, microstructure, cooking loss, and texture properties.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!