The aim of this research was to investigate the possibility of differentiation between black powder toners of similar polymer composition applying analytical methods: Fourier transform infrared spectrometry (FTIR) and X–ray fluorescence spectrometry (XRF). The studied materials were black powder toners of similar polymer composition sampled from the cartridges of 34 machines (31 models purchase...

Soil samples were collected from five provinces over China, including Beijing, Xinjiang, Heilongjiang, Yunnan, and Jiangsu. Heavy metal Cr, Zn, Pb and As in soils were analyzed by a portable X-ray fluorescence spectrometry (XRF). For predicating metal concentration in soils, a partial least square regression model (PLSR) was established. After cross-calibration, the correlation coefficients for...

The accuracy, repeatability and detection limits of the energy-dispersive X-ray fluorescence (XRF) spectrometer used in this study were tested to verify its suitability for rapid screening of cadmium in samples. Concentrations of cadmium in rice grain samples were tested by the XRF spectrometer. The results showed that the apparatus had good precision around the national limit value (0.2 mg/kg)...

Patients with Graves' disease can be medically prepared before surgery in different ways, which may have various effects on iodine stores. Thyroid specimens were collected at surgery from two patients pretreated with propylthiouracil (PTU) and stable iodine, respectively. A quantitative analysis of iodine content was performed using X-ray fluorescence (XRF) in frozen tissue and a qualitative an...

The application of ultrafiltration for milk concentration allows obtaining a raw material for yoghurt elaboration, with total solids increased. The products have special characteristics due to different ratios proteins/lactose can be obtained, as well as they have nutritional properties with beneficial effects in human health. In this study the content of calcium, potassium, phosphorous, iron, ...

Neural networks are shown to be useful as emplncal mathematical models m the calculation of quantltatlve analytical results, gvmg sufflclent accuracy to compete successfully with various common cahbratlon procedures. The performance of these neural-network models for cahbratlon data from x-ray fluorescence spectrometry (XRF) was evaluated for two trammg methods, 1 e , backward error propagation...

A study was undertaken to determine if laser-induced breakdown spectroscopy (LIBS) can be a practical and competitive alternative to X-ray fluorescence (XRF) methods for lead-in-paint inspection. Experiments in the laboratory confirmed that LIBS is suitable for detecting lead in paint at the hazard levels defined by federal agencies. Although we compared speed, function and cost, fundamental di...

We present the results from a Hubble Space Telescope/ACS study of the supernovae associated with gamma-ray bursts 040924 (z = 0.86) and 041006 (z = 0.71). We find evidence that both GRBs were associated with a SN1998bw-like supernova dimmed by ∼ 1.5 and ∼ 0.3 magnitudes, respectively, making GRB040924 the faintest GRB-associated SN ever detected. We study the luminosity dispersion in GRB/XRF-as...

Several techniques have been utilized for the preparation of hydroxyapatite (HA) and other calcium phosphates for the development of biomaterials. It is vital to know the reaction kinetics to be able to control the material obtained by the aqueous solution route. In the present work, HA has been produced by different wet precipitation processes and different experimental conditions. Calcium hyd...