scholarly journals Physical Characterisation of a Natural Zeolite using a Scanning Electron Microscopy: A Preliminary Study

2021 ◽  
Vol 1 (1) ◽  
pp. 510-513
Author(s):  
Ali Munawar ◽  
Djoko Mulyanto ◽  
R. R. Dina Asrifah

Zeolite is one of important non-metallic mineral deposites in Indonesia. It has been used for various purposes, including as an adsobent in environmental protection, industry, and agriculture. The most important characteristics of zeolit to be an adsorbent is its surface area and crystal structure. To optimally use zeolite as an adsorbent, it is necessary to understand its physical characteristics. This preliminary study was aimed to characterize physical properties of a natural zeolite obtained from Tasikmalaya, West Java, Indonesia. The zeolite material was crushed into <0.5 mm diameter and divided into two sets of samples. One set of samples was heated in a muffle furnace at 250 oC for two hours and the other set was left untreated. All samples were then observed using a Scanning Electron Microscopy (SEM). The SEM micrographs showed rough and porous structure and defined crystallinity of the zeolite. Thermal treatment at 250 oC increased zeolite crystallinity. These results confirm that this natural zeolite is potential to be used as an adsorbent to remove dissolved metals from acid mine drainage.

1994 ◽  
Vol 6 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Marek R. Lipinski ◽  
M. Deon Durholtz

It appears that squid statoliths cannot yet be regarded as accurate an ageing tool as fish otoliths. Statoliths from the same pair, prepared differently for viewing and counting increments, were compared. Increment counts do not imply age in days, because this was not validated. One statolith from each pair was examined by light microscopy (LM) after preparation following a new method. The other was viewed by Scanning Electron microscopy (SEM) with a modified etching solution. Shape of each statolith was similar when compared by multiple regression analysis (11 variables, n=53). There was a weak but significant difference between sexes (statoliths of females were slightly larger). All other differences were insignificant. Microscopic observation and increment counts of increments were successfully carried out for 37 pairs of statoliths. Significant differences between two independent counts were found for the LM method, but no significant differences were found between two independent SEM counts. Counts were significantly different when interpreted by both LM and SEM, probably because of poor resolution in the LM readings and over-resolution (growth layers prominent and numerous) in those read by SEM. Recommendations are made on how ageing studies, based on statoliths, should be structured and the results evaluated.


Phytotaxa ◽  
2015 ◽  
Vol 207 (1) ◽  
pp. 135 ◽  
Author(s):  
Giovanni Raul Bogota ◽  
Carina Hoorn ◽  
Wim Star ◽  
Rob Langelaan ◽  
Hannah Banks ◽  
...  

Sabinaria magnifica is so far the only known species in the recently discovered tropical palm genus Sabinaria (Arecaceae). Here we present a complete description of the pollen morphology of this palm species based on light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We also made SEM-based comparisons of Sabinaria with other genera within the tribe Cryosophileae. Pollen grains of Sabinaria magnifica resemble the other genera in the heteropolar, slightly asymmetric monads, and the monosulcate and tectate exine with perforate surface. Nevertheless, there are some clear differences with Thrinax, Chelyocarpus and Cryosophila in terms of aperture and exine. S. magnifica differs from its closest relative, Itaya amicorum, in the exine structure. This study shows that a combination of microscope techniques is essential for the identification of different genera within the Cryosophileae and may also be a necessary when working with other palynologically less distinct palm genera. 


2019 ◽  
Vol 105 (5) ◽  
pp. 404-410 ◽  
Author(s):  
Federica Grosso ◽  
Alessandro Croce ◽  
Roberta Libener ◽  
Narciso Mariani ◽  
Massimo Pastormerlo ◽  
...  

Purpose: To assess whether asbestos fibers may be observed in liver tissue of patients with cholangiocarcinoma (CC) with environmental or working asbestos exposure. Methods: Detection of fibers was performed directly on histologic sections of liver from 7 patients with CC using optical microscope and variable pressure scanning electron microscopy equipped with energy-dispersive spectroscopy (VP-SEM/EDS). All patients were from Casale Monferrato, Italy, a highly asbestos-polluted town. Due to ethical constraints, observers were blinded to patients’ clinical features. Results: Fibers/bundles of fibers of chrysotile were detected in 5 out of 7 patients (71%). The boundary between healthy and neoplastic tissue or the fibrocollagen tissue produced by the neoplasia were identified as areas of fiber incorporation. Conclusions: This study is the first report about the detection of chrysotile asbestos fibers in the liver of patients with CC. Further studies on larger cohorts are needed to corroborate our preliminary findings.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Lucas Pereira Borges ◽  
Julio Cesar Campos Ferreira-Filho ◽  
Julia Medeiros Martins ◽  
Caroline Vieira Alves ◽  
Bianca Marques Santiago ◽  
...  

The purpose of this work was to verifyin vitroadherence ofE. corrodensandS. oralisto the surface of tongue piercings made of surgical steel, titanium, Bioplast, and Teflon. For this, 160 piercings were used for the count of Colony Forming Units (CFU) and 32 piercings for analysis under scanning electron microscopy. Of these, 96 (24 of each type) were individually incubated in 5 mL of BHI broth and 50 μL of inoculum at 37°C/24 h. The other 96 piercings formed the control group and were individually incubated in 5 mL of BHI broth at 37°C/24 h. Plates were incubated at 37°C/48 h for counting of CFU/mL and data were submitted to statistical analysis (pvalue<0.05). ForE. corrodens, difference among types of material was observed (p<0.001) and titanium and surgical steel showed lower bacterial adherence. The adherence ofS. oralisdiffered among piercings, showing lower colonization (p<0.007) in titanium and surgical steel piercings. The four types of piercings were susceptible to colonization byE. corrodensandS. oralis, and bacterial adhesion was more significant in those made of Bioplast and Teflon. The piercings presented bacterial colonies on their surface, being higher in plastic piercings probably due to their uneven and rough surface.


Zootaxa ◽  
2007 ◽  
Vol 1397 (1) ◽  
pp. 39-45 ◽  
Author(s):  
CRISTINA DE VILLALOBOS ◽  
FERNANDA ZANCA ◽  
SERGEI SPIRIDONOV

We reinvestigate four species of the genus Chordodes from Central Asia and one from Georgia (Transcaucasian part of former USSR) in order to certify the taxonomic descriptions and verify the species status. By scanning electron microscopy, we demonstrate characteristic cuticular patterns for Chordodes anthophorus. The other three species, C. aquaeductus, C. ferganensis and C. oscillatus are synonymized with C. anthophorus because no differences were detected.


2005 ◽  
Vol 16 (2) ◽  
pp. 129-134 ◽  
Author(s):  
Newton Sesma ◽  
Dalva Cruz Laganá ◽  
Susana Morimoto ◽  
Carlos Gil

This study evaluated, in vivo, the efficacy of a denture glazing material (Palaseal) in modifying plaque colonization of dentures. Ten subjects were selected and received maxillary temporary partial removable dentures, with complete acrylic palatal coverage. The right half of the fitting surface of the denture bases were glazed with Palaseal, whereas the other half was not glazed. One month after insertion, two fragments of the resin base of all dentures were removed (one from the glazed side and another from the non-glazed side). These samples were prepared and examined by scanning electron microscopy. Three months after insertion, other fragments were obtained and analyzed. Microscopic observation at 1 month revealed that, for all patients, the plaque film was thinner on the treated side in comparison to the non-treated side. However, at the 3-month evaluation, some areas of the glaze showed cracking, and both glazed and non-glazed sides were covered by a dense bacterial plaque film. In conclusion, the findings of this clinical experiment showed that glazing denture's fitting surface did not prevent bacterial colonization, but favored plaque removal while the glaze layer remained intact. After three months, glaze cracks created microretentive areas that increased plaque accumulation.


1988 ◽  
Vol 66 (5) ◽  
pp. 829-838 ◽  
Author(s):  
M. J. Hodson ◽  
A. G. Sangster

Silica deposition in the lower glume, lemma, and palea of wheat (Triticum aestivum L. cv. Highbury) was investigated using scanning electron microscopy and light microscopy. Silica was present in the outer walls of all the epidermal cells including prickles and papillae of the glume and lemma awns. The glume and the lemma were similar in epidermal silica deposition pattern, both having numerous silicified short trichomes and papillae on inner and outer surfaces. Epidermal long cells and short cells were also silicified. Macrohairs were restricted to isolated areas in these bracts, particularly on the inner surfaces just beneath the awns. The palea was a thin membranous structure differing markedly from the other two bracts. Most of the palea is pressed between the caryopsis and the next floret, and both surfaces are almost devoid of trichomes in these areas. However, at the apex and margins of the palea, macrohairs and papillae were abundant. The results are discussed with respect to possible taxonomic, anatomical, medical, and archaeological implications.


1994 ◽  
Vol 68 (4) ◽  
pp. 319-322 ◽  
Author(s):  
F. Moravec ◽  
A. Kohn ◽  
B.M.M. Fernandes

AbstractThe cephalic end of the type species of pharyngodonid genera Travnema and Cosmoxynemoides, T. travnema Pereira, 1938 and C. aguirrei Travassos, 1949, parasites of Brazilian freshwater fishes, was studied by scanning electron microscopy. The mouth aperture of Travnema was found to be circular, surrounded by four cephalic papillae and two lateral amphids and the cuticle of the cephalic end had a conspicuous dense sculpture. On the other hand, the mouth aperture of Cosmoxynemoides was triangular, surrounded by three lip-like elevations covering the whole surface of the relatively flat cephalic extremity, each with two inner lobes separated one from another by a short groove; the lip-like elevations bore four medium-sized, kidney-shaped cephalic papillae and two minute amphids (two papillae on the dorsal elevation and one papilla and one amphid on each of two ventrolateral elevations); the cuticle of the cephalic end was smooth. Both species were noted for the absence of oral lamellae and the presence of lateral alae. Both genera are listed in the family Pharyngodonidae but Travnema (and also Hakynema), due to its morphological peculiarities, is considered to represent a distinct subfamily Travnematinae within the Pharyngodonidae. The finding of both T. travnema and C. aguirrei in the characid fish Astyanax bimaculatus lacustris represents new host records.


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