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Abstract  

Use of autoradiography and scanning electron microscopy, coupled with potentiometric and radionalytical investigation techniques, allows to confirm experimentally that the rate of Cl→SO 4 2− conversion of different anion resins at 0.006N solution concentration is not controlled) by ion interdiffusion and that sulfate penetration into the resin bead occurs according to a progressive conversion mechanism.

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Abstract  

Potsherds were analyzed chemically by four different techniques. Results are compared for many elements. The effect of temper appears as a problem because of the inhomogeneity of the bulk. PIXE and neutron activation are powerful and complementary methods to obtain element concentrations for proveniance studies. Also scanning electron microscopy and the electron microprobe are very useful to detect and analyze the tempers. Thus it is possible to gather data on the potter technology. In conclusion the use of a proton microprobe seems to be a promising instrument for versatile analyses.

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Abstract  

Commercial light-cured dental composites were used in this study. Two laboratorial composites, Resilab (Wilcos/Brazil), Epricord (Kuraray/Japan) were compared under cured and uncured conditions. Thermal analysis, infrared spectroscopy and scanning electron microscopy were used to evaluate the dental composites. The mass change and heat flow signals (TG–DSC) were recorded simultaneously by using STA 409 PC Luxx (NETZSCH), in the 25–800 °C temperature range at a heating rate of 10 °C/min under nitrogen atmosphere (70 mL/min). Employing thermo-microbalance TG 209 C F1 Iris (NETZSCH) coupled to the BRUKER Optics FTIR TENSOR, the samples were analyzed by combined thermogravimetric and spectroscopic methods (TG–FTIR). The initial sample mass was about ~12 mg, the data collection have been done in the 35–800 °C temperature range at a heating rate of 20 K/min in nitrogen atmosphere (flow rate: 40 mL/min). Finally, superficial topographic was analyzed by scanning electron microscopy (SEM). Dental composite evaluation suggests a high thermal stability and inorganic content in RES D sample. Degrees of conversion (DC) values were almost the same and there was no direct relationship between DC and amount of particles and size. Similar compositions were found in all samples.

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Plankton samples collected from a yellow watered bog pool of the mesotrophic “Călăţele Pădurii” peat bog (Romanian Western Mountains, Transylvania), exhibited an outstandingly rich Mallomonas population. The observations carried out by light and scanning electron microscopy revealed that the population belongs to Mallomonas intermedia Kisselev. Based on the presence of lance head bristles, distributed all over the cell armour (except few anterior collar, unilaterally serrated ones), it became evident that the population belong to the nominate variety (var. intermedia). Mallomonas intermedia var. saliceaensis formerly described from Transylvania differs by the type variety by the presence of exclusively serrated bristles. The present finding proved that Mallomonas intermedia could not be properly identified at infraspecific level solely based on the ultra structure of scales, without knowing the structure of bristles, too.

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N. A. , Craven J. P. , Donald A. M. , Terentjev E. M. , Thiel B. L. Topographic contrast of partially wetting water dropelts in environmental scanning electron microscopy , Journal of Microscopy , Vol. 204 , No. 2

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scanning electron microscopy. In: J. J. Bozzola, L. D. Russel (eds) Electron Microscopy. Jones and Bartlett Publishers, London, pp. 40-64. Specimen preparation for scanning electron microscopy

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Abstract  

X-ray fluorescence, using the fundamental parameters method for matrix correction, is used routinely for quantitative analysis in our group. The accuracy of this method has been demonstrated with a Nd:YAG (Nd:Y3Al5O12) laser crystal. The neodymium concentration was determined relatively to the yttrium concentration by X-ray fluorescence using241Am for excitation. The yttrium-aluminum ratio was confirmed by scanning electron microscopy (SEM-EDX). Although there was a 10% discrepancy for yttrium due to the uncertainty in the neutron capture cross-section, the fluorescence results for aluminum and neodymium were in very good agreement with neutron activation analysis (NAA) results. Based on this agreement, the Nd:YAG sample will be used in future NAA calibration measurements.

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Abstract  

Samples of total suspended particles (TSP) and PM10 respirable particles from five monitoring stations from the network system of the Metropolitan Zone of the Valley of Mexico (MZVM) were analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDX). Morphology and chemical composition allowed to identify six groups. The analysis shows that the most abundant groups are Al-Si-O, Fe, and metals, the first one in the TSP fraction. Trace metal, commonly associated to PM10 at a receptor location, will depend on the relative influences of local anthropogenic sources. Metal group was observed in all samples, mainly in Tlalnepantla and CES zones (28–46%).

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Abstract  

The relative merits and sampling requirements of instrumental neutron activation analysis (INAA) and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) analysis as applied to the continental component of marine aerosols are discussed. When correlated with air mass information, the quantitative INAA data on the concentrations of 15 major and minor elements in the continental dust fraction provides information on the geochemical type and location of the land source. Although the SEM/EDS technique provides only qualitative concentrations for 6 additional elements in the aerosol, the important feature of single particle analysis enables more nearly synoptic interpretation of aerosol composition and concentration. A combined INAA and SEM/EDS study of the aerosol samples is therefore preferred.

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Giannetto, S. (2003): Thelazia callipaeda (Spirurida, Thelaziidae) of carnivores and humans: morphological study by light and scanning electron microscopy. Parassitologia 45, 125-133. Thelazia callipaeda (Spirurida, Thelaziidae

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