A prior report demonstrated an unacceptably low level of accuracy in silica analytical testing, with a general negative bias (i.e., underreporting) although other inaccuracies included false-positive results when analyzing blank filters. The possible bias may have been due to the loss of sample during shipping and or sample preparation. We report on a follow-up study that was designed to mimic the original study, but in which sources of variability were evaluated. We found no effect on silica recoveries due to shipping and confirmed the prior study results that the muffle furnace ashing process led to low overall recoveries (49-104%), depending on the adherence to the recommended preparation method. Plasma ashing recoveries ranged from 89 to 108%. Our results suggest that muffle-furnace ashing using a crucible should be restricted. More broadly, however, muffle-furnace ashing is only one source of analytical error that contributes to the relatively poor overall performance revealed by Cox et al. Whatever the case, OSHA should ensure that its proposed requirements to improve laboratory performance will actually lead to the discovery and correction of all major sources of error by participating laboratories. This is particularly important in light of OSHA's proposed reduction in the PEL and action level proposed by OSHA.
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http://dx.doi.org/10.1016/j.yrtph.2016.06.002 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States.
The widespread use of gadolinium-based contrast agents for magnetic resonance imaging (MRI) in recent decades has led to a growing demand for Gd and raised environmental concerns due to their direct discharge into wastewater systems. In response, we developed an electrochemical filtration method to recover Gd from patient urine following contrast-enhanced MRI. This method involves modifying a conventional vacuum filtration apparatus by introducing electrodes into the filter membrane, creating a strong electric field of ∼5 kV/m and a steep three-zone pH gradient within the filter membrane.
View Article and Find Full Text PDFMorphologie
January 2025
Department of Biostatistics, KS Hegde Medical Academy, Nitte (deemed to be university), Mangalore, Karnataka, India.
Introduction: In the forensic field, having accurate understanding of the macroscopic and microscopic alterations that occur in teeth when exposed to temperatures has remarkable significance. The preservation of delicate incinerated teeth is crucial in fire investigations that pertain to the temperature exposed, as well as the identification of victims. This preservation is necessary in order to conduct macroscopic and microscopic ultra-structural examinations, which provide valuable insights into the structural alterations that dental tissues undergo when exposed to low to high temperatures.
View Article and Find Full Text PDFEnviron Monit Assess
December 2024
Department of Plant Sciences, North Dakota State University, Fargo, 58108 ND, USA.
In this study, the elemental contents of almonds burned with four different methods to capture the elemental amount of almond kernels in the best way, to increase the release of obtainable elements by decomposing plant tissues, and to make them more atomized were measured and compared with ICP-AES. Depending on the digestion types, the K and Ca contents of almond varieties were determined as 10,167.35 (microwave) and 13,004.
View Article and Find Full Text PDFMolecules
November 2024
Chemical Department, Institute of General and Ecological Chemistry, Lodz University of Technology, Zeromskiego 116, 90-543 Lodz, Poland.
The aim of this work was to investigate the hydrocracking of algae oil derived from Spirulina Platensis species catalyzed with bi-component nickel-zirconia catalysts supported onto different carriers (BEA, ZSM-5 and AlO) in an autoclave at 320 °C for 2 h with a hydrogen pressure of 75 bar. All catalysts were prepared using the wet co-impregnation method and were characterized by H-TPR, XRD, NH-TPD, BET and SEM-EDS. Before reactions, catalysts were calcined at 600 °C for 4 h in a muffle furnace, then reduced with 5%H-95%Ar reducing mixture at 500 °C, 600 °C or 700 °C for 2 h.
View Article and Find Full Text PDFJ Colloid Interface Sci
February 2025
National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Shanghai Jiao Tong University, Shanghai 200240, China.
Thermal barrier coatings (TBCs) have garnered significant attention as crucial protective components for turbine blades. However, the current use of TBCs is limited by their singular functionality and the inability to accurately obtain the temperature gradient distribution within the coatings. Addressing the aforementioned issues, this paper proposes an intelligent thermal barrier coating embedded with thin-film thermocouples.
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