scholarly journals Accurate and Precise Determination of Silver Isotope Fractionation in Environmental Samples by Multicollector-ICPMS

2010 ◽  
Vol 82 (9) ◽  
pp. 3922-3928 ◽  
Author(s):  
Yan Luo ◽  
Ewa Dabek-Zlotorzynska ◽  
Valbona Celo ◽  
Derek C. G. Muir ◽  
Lu Yang
Keyword(s):  
Environmental Samples ◽  
Isotope Fractionation ◽  
Precise Determination ◽  
Silver Isotope

Recent Advances in Miniaturized Microextraction Techniques for the Determination of Bisphenols in Environmental Samples: An Overview of the last two Decades

2020 ◽  
Vol 16 ◽  
Author(s):  
Athanasios Tsalbouris ◽  
Natasa P. Kalogiouri ◽  
Victoria F. Samanidou
Keyword(s):  
Environmental Samples ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Precise Determination ◽  
Stir Bar Sorptive Extraction ◽  
Environmental Matrices ◽  
Industrial Chemicals ◽  
Recent Advances ◽  
Microextraction Techniques

Background: Bisphenols are major industrial chemicals that have raised public concern due to their endocrine disrupting properties and toxicity. Sample preparation is the most critical step for determination of bisphenols, especially if the analyst has to deal with environmental samples which are complex matrices and the co-extraction and co-elution of other relevant compounds results in the enhancement or suppression of the analyte signal. The need for the precise determination of bisphenols has signaled the development of effective microextraction techniques according to the Green Analytical Chemistry (GRAC) guidelines. Objective: The objective of this review is to gather and discuss all the recent advances in the development of microextraction techniques such as solid phase extraction (SPE), solid phase microextraction (SPME), magnetic solid phase microextraction (MSPE), liquid-phase microextraction (LPME), dispersive liquid-liquid microextraction (DLLME), stir bar sorptive extraction (SBSE), matrix solid-phase dispersion (MSPD), that have been successfully applied in the extraction of bisphenols from environmental matrices. Conclusion: The analytical performance of the proposed techniques is critically discussed highlighting the potential and the limitations of each method.

scholarly journals Precise determination of HPGe detector efficiency for gamma spectrometry measurements of environmental samples with variable geometry and density

Nukleonika ◽  
2017 ◽  
Vol 62 (1) ◽  
pp. 47-59 ◽  
Author(s):  
Manuel Barrera ◽  
Melquiades Casas-Ruiz ◽  
José J. Alonso ◽  
Juan Vidal
Keyword(s):  
Gamma Spectrometry ◽  
Environmental Samples ◽  
Hpge Detector ◽  
Attenuation Factor ◽  
Cylindrical Sample ◽  
Precise Determination ◽  
Energy Peak ◽  
Full Energy Peak Efficiency ◽  
Good Agreement

Abstract A methodology to determine the full energy peak efficiency (FEPE) for precise gamma spectrometry measurements of environmental samples with high-purity germanium (HPGe) detector, valid when this efficiency depends on the energy of the radiation E, the height of the cylindrical sample H, and its density ρ, is introduced. The methodology consists of an initial calibration as a function of E and H and the application of a self-attenuation factor, depending on the density of the sample ρ, in order to correct for the different attenuation of the generic sample in relation to the measured standard. The obtained efficiency can be used in the whole range of interest studied, E = 120–2000 keV, H = 1–5 cm, and ρ = 0.8–1.7 g/cm3, being its uncertainty below 5%. The efficiency has been checked by the measurement of standards, resulting in a good agreement between experimental and expected activities. The described methodology can be extended to similar situations when samples show geometric and compaction differences.

PRECISE DETERMINATION OF THE IRRATIONAL PRE-FERRED INTERFACE ORIENTATION BY TEM

2010 ◽  
Vol 46 (4) ◽  
pp. 411-417 ◽  
Author(s):  
Yang MENG ◽  
Lin GU ◽  
Wenzheng ZHANG
Keyword(s):  
Precise Determination ◽  
Interface Orientation

Nauwkeurige methode voor de aanwasbepaling van het grondvlak met behulp van de Pressler-boor

1968 ◽  
Vol 12 ◽  
Author(s):  
R. Goossens
Keyword(s):  
Basal Area ◽  
Precise Determination ◽  
Maximum Diameter ◽  
Precise Method ◽  
Maximum Radius ◽  
The Core ◽  
Two Parameters

A precise method for the determination of the increment of the  basal area using the PressIer bore. Refering to  previous research showing that the basal area of the corsica pine could be  characterized by an ellips, we present in this paper a precise method for the  determination of the increment of the basal area. In this method we determine  the direction of the maximum diameter, we measure this diameter and we take a  core in one of the points of tangency of the caliper with the measured tree.  The determination of the diameter perpendicular to the maximum diameter  finishes the work wich is to be done in the forest. From the classical  measurements effectuated on the core and from the measured diameters we can  then determine the form (V) and the excentricity (e). Substituting these two  parameters in the formula 2 or 2', we can also calculate the error of a  radius measured on the core with respect to the representative radius, This  error with them allow us to correct the measured value of the minimum or the  maximum radius and we will be able to do a precise determination of the  increment.

Sign in / Sign up

Export Citation Format

Share Document