Search results for "ESOL"
showing 10 items of 2444 documents
Determination of Amitriptyline with Bromocresol Purple and Flow Injection Analysis
1990
Abstract The study of some amitriptyline-dye systems was carried out in order to determine the best precipitate for the turbidimetric determination of amitriptyline using FIA. The reagent selected was bromocresol purple. The chemical and FIA variables were optimized. The calibration graph was linear over the concentration range 30.0–200.0 ppm of amitriptyline hydrochloride. Some interfering substances were also investigated.
FTIR approaches for diuron determination in commercial pesticide formulations.
2005
Two strategies have been developed for Diuron determination by FTIR spectrometry, an off-line extraction and stopped-flow determination and a fully mechanized procedure, based on the on-line extraction of Diuron and FIA-FTIR measurement of the extracts. The aforementioned procedures have been compared with a reference chromatographic method. The off-line FTIR spectra were obtained at a nominal resolution of 4 cm(-1) from 4000 to 900 cm(-1) by accumulating 25 scans. Diuron was determined using peak height measurements at 1582 cm(-1) corrected using a baseline defined between 1562 and 1614 cm(-1). The waste generation of the off-line procedure was 3.4 mL chloroform for each sample, and the me…
Applications of Super Resolution Expansion Microscopy in Yeast
2021
Super-resolution microscopy includes multiple techniques in optical microscopy that enable sub-diffraction resolution fluorescence imaging of cellular structures. Expansion microscopy (EXM) is a method of physical expansion to obtain super-resolution images of a biological sample on conventional microscopy. We present images of yeast organelles, applying the combination of super-resolution and ExM techniques. When preparing pre-expanded samples, conventional methods lead to breakage of dividing yeast cells and difficulties in studying division-related proteins. Here, we describe an improved sample preparation technique that avoids such damage. ExM in combination with Airyscan and structured…
Analysis of 18 perfluorinated compounds in river waters: Comparison of high performance liquid chromatography–tandem mass spectrometry, ultra-high-pe…
2012
In this work, the performance of ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and capillary liquid chromatography-mass spectrometry (CLC-MS) has been studied for the analysis of eighteen perfluorinated compounds in water samples. UHPLC-MS/MS and CLC-MS analysis were carried out using a Zorbax C-18 column (50 mm × 2.1 mm, 1.8 μm) and a Zorbax SB-C18 column (150 mm × 0.5 mm, 3.5 μm), respectively, in gradient elution mode with a mobile phase of ammonium formate and methanol. Both techniques were compared with conventional LC-MS/MS in terms of speed, sensitivity, selectivity and resolution. Water samples were extracted by solid phase extraction (SPE). Mea…
Performance evaluation of a high resolution dedicated breast PET scanner
2016
Purpose: Early stage breast cancers may not be visible on a whole-body PET scan. To overcome whole-body PET limitations, several dedicated breast positron emission tomography (DbPET) systems have emerged nowadays aiming to improve spatial resolution. In this work the authors evaluate the performance of a high resolution dedicated breast PET scanner (Mammi-PET, Oncovision). Methods: Global status, uniformity, sensitivity, energy, and spatial resolution were measured. Spheres of different sizes (2.5, 4, 5, and 6 mm diameter) and various 18 fluorodeoxyglucose (18F-FDG) activity concentrations were randomly inserted in a gelatine breast phantom developed at our institution. Several lesion-to-ba…
2000 years of parallel societies in Stone Age Central Europe.
2013
Farming or Fishing Evidence has been mounting that most modern European populations originated from the immigration of farmers who displaced the hunter-gatherers of the Mesolithic. Bollongino et al. (p. 479 , published online 10 October) present analyses of palaeogenetic and isotopic data from Neolithic human skeletons from the Blätterhöhle burial site in Germany. The analyses identify a Neolithic freshwater fish–eating hunter-gatherer group, living contemporaneously and in close proximity to a Neolithic farming group. While there is some evidence that hunter-gatherer women may have admixed into the farming population, it appears likely that marriage or cultural boundaries between the group…
Vibrational spectra and force constants of symmetric tops
1983
The infrared spectrum of H3SiI in the 800–1050 cm-1 region has been recorded with a resolution of 0·04 cm-1 and rotationally analysed. Features related to the Fermi resonance between v 5 and v 3 + v 6 and to the Coriolis x, y resonance between v 2 and v 5 have been explained, and a set of vibration-rotation parameters for the three bands has been determined by least-squares calculations, σ(J, K) = 9·4 × 10-3 cm-1. The Fermi resonance matrix element |W 356| is found to be 3·7859(7) cm-1 and the vibrational frequencies are v 2 0 = 904·551(1), v 5 0 = 941·0746(8) and (v 3 + v 6)0 = 953·688(3) cm-1. The anharmonicity constant, x 36 = -1·745(9) cm-1, has been determined. Comparison is made with …
Testing Ikonos and Landsat 7 ETM+ Potential for Stand-Level Forest Type Mapping by Soft Supervised Approaches
2003
Forest types can be adopted as a suitable reference for classifying survey units within multipurpose forest resources inventories, at the properly considered level. This kind of hierarchical classification approach integrates an ecologically meaningful per-habitat perspective with practical survey, planning and management requirements. Advanced remote sensing technologies can be valuable tools for a cost-effective implementation of such an approach. In the present paper, data from high (Landsat 7 ETM+) and very high (Ikonos) spatial resolution satellite sensors were tested to understand their potential contribution supporting stand-level forest type mapping under Mediterranean conditions. I…
Evaluation of methods aimed at complete removal of template from molecularly imprinted polymers
2001
Polymers imprinted with clenbuterol were used to study the influence of various post-polymerization treatments [e.g., thermal annealing, microwave assisted extraction (MAE), Soxhlet extraction and supercritical fluid template desorption] on the bleeding of residual template. The aim of the study was to reduce the bleeding to levels that would allow the use of the materials as affinity phases for extraction of clenbuterol from bovine urine at concentrations below 1 ng ml−1. After treatment, the clenbuterol imprinted polymers were packed into solid-phase extraction columns and the bleeding was estimated by quantifying the amount of template released in 10 ml of methanol–acetic acid (9 + 1 v/v…
k-Space filtering in 2D gradient-echo breath-hold hyperpolarized3He MRI: Spatial resolution and signal-to-noise ratio considerations
2002
In this work some of the factors that can influence the signal-to-noise ratio (SNR) and spatial resolution in MR images of inhaled hyperpolarized gases are systematically addressed. In particular, the effects of RF depletion of longitudinal polarization and image gradient diffusion dephasing were assessed in terms of their contribution to a k-space filter. By means of theoretical simulations and a novel method of experimental validation using a variable transverse magnetization of the 1H signal, systematic quantitative and qualitative investigations of the effects of k-space filtering intrinsic to imaging of hyperpolarized gas were made. A 2D gradient-echo image is considered for a range of…