Rare-earth elements in Egyptian granite by instrumental neutron activation analysis.

Appl Radiat Isot

Physics Department, Faculty of Science, Al-Azher University, Assuit Branch, Egypt.

Published: April 2007

The mobilization of rare-earth elements (REEs) in the environment requires monitoring of these elements in environmental matrices, in which they are mainly present at trace levels. The similarity in REEs chemical behavior makes the separate determination of each element by chemical methods difficult; instrumental neutron activation analysis (INAA), based on nuclear properties of the elements to be determined, is a method of choice in trace analysis of REEs and related elements. Therefore, INAA was applied as a sensitive nondestructive analytical tool for the determination of REEs to find out what information could be obtained about the REEs of some Egyptian granite collected from four locations in Aswan area in south Egypt as follows wadi El-Allaqi, El-Shelal, Gabel Ibrahim Pasha and from Sehyel Island and to estimate the accuracy, reproducibility and detection limit of NAA method in case of the given samples. The samples were properly prepared together with standards and simultaneously irradiated in a neutron flux of 7 x 10(11)n/cm(2)s in the TRIGA Mainz research reactor facilities. The following elements have been determined: La, Ce, Nd, Sm, Eu, Yb and Lu. The gamma spectra was collected by HPGe detector and the analysis was done by means of computerized multichannel analyzer. The X-ray fluorescence (XRF) was also used.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.apradiso.2006.07.014DOI Listing

Publication Analysis

Top Keywords

rare-earth elements
8
egyptian granite
8
instrumental neutron
8
neutron activation
8
activation analysis
8
elements determined
8
elements
5
rees
5
elements egyptian
4
granite instrumental
4

Similar Publications

With the progress of atherosclerosis (AS), the arterial lumen stenosis and compact plaque structure, the thickening intima and the narrow gaps between endothelial cells significantly limit the penetration efficiency of nanoprobe to plaque, weakening the imaging sensitivity and therapy efficiency. Thus, in this study, a HO-NIR dual-mode nanomotor, Gd-doped mesoporous carbon nanoparticles/Pt with rapamycin (RAPA) loading and AntiCD36 modification (Gd-MCNs/Pt-RAPA-AC) was constructed. The asymmetric deposition of Pt on Gd-MCNs catalyzed HO at the inflammatory site to produce O, which could promote the self-motion of the nanomotor and ease inflammation microenvironment of AS plaque.

View Article and Find Full Text PDF

Molecular Uranium Dioxide-Mediated CO Photoreduction.

J Am Chem Soc

January 2025

Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education, Tsinghua University, Beijing 100084, China.

The reduction of CO mediated by transition metals has garnered significant interest, yet little is known about the reduction of CO using f-element compounds. Herein, the reduction of CO to CO by tetravalent uranium (U) compound UO is investigated via matrix isolation infrared spectroscopy and quantum chemical study. Our results reveal that a stable carbonate intermediate OUCO () can be prepared at low temperatures (4-12 K).

View Article and Find Full Text PDF

Near-infrared wavelength-selective soft actuators have attracted much attention for applications in microsystems in bioliving. It is desirable for the photothermal conversion materials in the actuators to be downsized to the molecular scale. However, in conventional actuator materials using copolymer gels composed of thermosensitive and photothermal conversion molecule-coordinated monomers, the strong cross-linking of molecules in the networks impairs the actuator deformation.

View Article and Find Full Text PDF

Normative measurements of the frontal nerve by magnetic resonance imaging in an Australia cohort.

Surg Radiol Anat

January 2025

Department of Ophthalmology & Visual Sciences, University of Adelaide, North Terrace, Adelaide, SA, 5000, Australia.

Purpose: To report the normative dimensions of the frontal nerve (FN) on fat-suppressed suppressed gadolinium (fs-gad) enhanced magnetic resonance imaging (MRI).

Method: A retrospective cohort study of patients who underwent coronal fs-gad T1-weighted MRI. Orbits were excluded if there was unilateral or bilateral pathology of the FN or optic nerve sheath (ONS), incomplete MRI sequences, poor image quality or indiscernible FN on radiological assessment.

View Article and Find Full Text PDF

Purpose: To compare the effect on sexual function of ejaculation-sparing enucleation of the prostate using Thulium: YAG laser (ES-ThuLEP) versus continuous-wave Thulium Fiber Laser (ES-ThuFLEP).

Methods: 112 patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia who wished to preserve ejaculation were treated. 58 patients underwent ES-ThuLEP (Group A) using the Cyber TM generator.

View Article and Find Full Text PDF

Want 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!