Characterization Of The Phase Evolution Of MoSi2/TiB2 Composites Produced By Elemental And Displacement In-Situ Reactions Using Scanning Electron Microscopy (SEM) And Electron Probe Microanalysis (EPMA)

2004 ◽  
Vol 10 (S02) ◽  
pp. 676-677
Author(s):  
Luisa A Dempere ◽  
Michael J Kaufman

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 446
Author(s):  
Ioannis Spanos ◽  
Zacharias Vangelatos ◽  
Costas Grigoropoulos ◽  
Maria Farsari

The need for control of the elastic properties of architected materials has been accentuated due to the advances in modelling and characterization. Among the plethora of unconventional mechanical responses, controlled anisotropy and auxeticity have been promulgated as a new avenue in bioengineering applications. This paper aims to delineate the mechanical performance of characteristic auxetic and anisotropic designs fabricated by multiphoton lithography. Through finite element analysis the distinct responses of representative topologies are conveyed. In addition, nanoindentation experiments observed in-situ through scanning electron microscopy enable the validation of the modeling and the observation of the anisotropic or auxetic phenomena. Our results herald how these categories of architected materials can be investigated at the microscale.


2007 ◽  
Vol 86 (9) ◽  
pp. 857-861 ◽  
Author(s):  
F. Rojas-Sánchez ◽  
M. Alaminos ◽  
A. Campos ◽  
H. Rivera ◽  
M.C. Sánchez-Quevedo

Dentin responds to different alterations in the enamel with hypermineralization, and is a biomarker of fluoride exposure. We hypothesized that severe fluorosis would lead to hypermineralization of the dentin when the enamel was severely affected. We used scanning electron microscopy and quantitative electron-probe microanalysis to compare dentin and enamel from healthy and fluorotic teeth. The dentin in fluorotic teeth was characterized by a highly mineralized sclerotic pattern, in comparison with control teeth (p < 0.001) and fluorotic enamel lesions (p < 0.001). Enamel near the lesions showed hypercalcification in comparison with dentin (p < 0.001). In response to the effects of severe fluorosis in the enamel, the dentin showed hypermineralization, as found in other enamel disorders. The hypermineralization response of the dentin in our samples suggests that the mechanism of the response should be taken into account in dental caries and other dental disorders associated with severe fluorosis.


1990 ◽  
Vol 22 (3) ◽  
pp. 345-354 ◽  
Author(s):  
O. William Purvis ◽  
John A. Elix ◽  
Kim L. Gaul

AbstractThe localization of psoromic acid and copper in partly green, copper-rich specimens of Lecidella bullata and Tephromela testaceoatra collected in Norway was studied by optical microscopy, scanning electron microscopy, and electron probe microanalysis. Infrared absorption spectroscopy of lichen material and of a synthetic copper-psoromic acid complex, and the other techniques, provide evidence that complexing of copper by psoromic acid occurs within specific areas of these lichens and this leads to their unusual colouration. In contrast, a specimen of copper-rich Lecanora cascadensis, which contains psoromic and usnic acids, does not contain such a complex. From the evidence obtained it is suggested that taxonomists should pay attention to the impact of rock and lichen chemistry on the appearance of lichen thalli.


Sign in / Sign up

Export Citation Format

Share Document