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Chemometric optimization of the extraction and derivatization of parabens for their determination in water samples by rotating-disk sorptive extraction and gas chromatography mass spectrometry
(Elsevier B.V., 2018)
© 2017 Elsevier B.V. A combination of rotating disk sorptive extraction (RDSE) using Oasis® HLB as the sorbent phase and gas chromatography mass spectrometry (GC-MS) has been performed for the determination of four of the ...
Rotating disk sorbent extraction for pre-concentration of chromogenic organic compounds and direct determination by solid phase spectrophotometry
(2011)
A novel and very simple microextraction approach for pre-concentration and direct solid phase spectrophotometric measurement has been developed for the determination of chromogenic analytes. The model analyte to assess ...
Net Nitrogen Mineralisation in Maize-Cover Crop Rotations in Mediterranean Central Chile
(Springer, 2020)
The main aim of this study was to evaluate the effects of the maize-cover crop rotation (Zm-cc) in the soil net nitrogen mineralisation (NNM) by measuring in situ NNM incubation in the upper soil (0-25 cm) during spring-summer ...
Radiation thermo-chemical models of protoplanetary discs IV. Modelling CO ro-vibrational emission from Herbig Ae discs
(EDP Sciences, 2013)
Context. The carbon monoxide (CO) ro-vibrational emission from discs around Herbig Ae stars and T Tauri stars with strong ultraviolet
emissions suggests that fluorescence pumping from the ground X1Σ+ to the electronic A1Π ...
A green and simple sample preparation method to determine pesticides in rice using a combination of SPME and rotating disk sorption devices
(Elsevier B.V., 2019)
In this study, a novel environmentally-friendly approach was developed to overcome certain limitations in the analysis of solid food samples. An experimental setup based on solid-phase microextraction apparatus coupled to ...
Rotating-disk sorptive extraction for the determination of sex hormones and triclosan in urine by gas chromatography-mass spectrometry: Clean-up integrated steps and improved derivatization
(Elsevier, 2020)
Different clean-up stages were coupled to rotating-disk sorptive extraction (RDSE) of testosterone, progesterone, 17 beta-estradiol and triclosan in urine samples prior to derivatization and detection by gas chromatography-mass ...
Hindered rotation of some substituted thioureas in complexes of chromium and tungsten carbonyls
(1980)
We describe a procedure for the preparation of various metal thiourea complexes of the type [M(CO)5L] in which M Cr or W and L TU (thiourea), TMTU (tetramethylthiourea), DptTU (NN′-di-p-totyl thiourea); DtBTU = (NN′-di-t-butyl ...
Amount of Rain Until Third Leaf Explain Differences in Irrigated Durum Wheat Yield Between a Conventional and No-Tillage System in a Long-Term Crop Rotation System in Mediterranean Environment
(Springer, 2019)
Crop yields usually respond to crop rotation, but they may interact with tillage system and year (as an integration of variables, mainly in terms of temperature and precipitation). The objective of this study was to evaluate ...
SMA millimeter observations of hot molecular cores
(The American Astronomical Society, 2014-05-07)
We present Submillimeter Array observations in the 1.3 mm continuum and the CH3CN (12K–11K) line of 17 hot
molecular cores associated with young high-mass stars. The angular resolution of the observations ranges from ...
A spectral survey of CH3CCH in the hot molecular core G331.512-0.103
(IOP, 2022)
A spectral survey of methyl acetylene (CH3CCH) was conducted toward the hot molecular core/outflow G331.512-0.103. Our APEX observations allowed the detection of 41 uncontaminated rotational lines of CH3CCH in the frequency ...