Olifantiella elisabethiana, a new raphid diatom species (Bacillariophyta) observed in the Port of Antwerp (Belgium)

During an extensive analysis of the diatom flora of the Port of Antwerp (Belgium) in 2008, an unknown naviculoid taxon was observed. Detailed morphological investigations using light, scanning electron and transmission electron microscopy resulted in the description of this unknown taxon as Olifantiella elisabethiana Van de Vijver sp. nov. This new small-celled, biraphid species is characterized in having a typical internal process named buciniportula, opening externally by a pore or slit, unseriate striae composed of one single transapically elongated areola and a siliceous hymenous velum extending internally from the valve mantle to halfway the valve margin and the axial area. The morphological observations allowed to precise the characterization of the genus Olifantiella. A modification of the original description is proposed with regard to the internal structure. The presence of this Olifantiella species in the northern hemisphere is briefly discussed as all other known taxa of this genus have only been found in the tropical coastal waters of the Indian and Pacific Ocean.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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Hydrothermal Synthesis and Characterization of BiFeO3 Polyhedral Crystallites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.174-177.508 ◽

2012 ◽

Vol 174-177 ◽

pp. 508-511

Author(s):

Lin Lin Yang ◽

Yong Gang Wang ◽

Yu Jiang Wang ◽

Xiao Feng Wang

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Xrd Pattern ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.

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Characterization of Al65.0Cu32.9Co2.1 Alloy Containing Nanofibres

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.186.212 ◽

2012 ◽

Vol 186 ◽

pp. 212-215

Author(s):

Jacek Krawczyk ◽

Włodzimierz Bogdanowicz ◽

Grzegorz Dercz ◽

Wojciech Gurdziel

Keyword(s):

Electron Microscopy ◽

Average Diameter ◽

Chemical Compositions ◽

X Ray ◽

Transmission Electron ◽

Orthogonal Set ◽

T Phase ◽

Terminal Area ◽

Scanning Electron

Microstructure of terminal area of Al65Cu32.9Co2.1ingots (numbers indicate at.%), obtained via directional solidification was studied. Scanning Electron Microscopy, Transmission Electron Microscopy and X-ray powder diffraction were applied. Point microanalysis by Scanning Electron Microscope was used for examination of chemical compositions of alloy phases. It was found that tetragonal θ phase of Al2Cu stoichiometric formula was the dominate phase (matrix). Additionally the alloy contained orthogonal set of nanofibres of Al7Cu2Co T phase with the average diameter of 50-500 nm and oval areas of hexagonal Al3(Cu,Co)2H-phase, surrounded by monoclinic AlCu η1phase rim. Inside some areas of H-phase cores of decagonal quasicrystalline D phase were observed.

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Synthesis and characterization of homogeneous lead-substituted tin oxide with the (110) face of rutile structure

Journal of Materials Research ◽

10.1557/jmr.2000.0298 ◽

2000 ◽

Vol 15 (10) ◽

pp. 2076-2079

Author(s):

Chika Nozaki ◽

Takashi Yamada ◽

Kenji Tabata ◽

Eiji Suzuki

Keyword(s):

Electron Microscopy ◽

Tin Oxide ◽

Photoelectron Spectroscopy ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Rutile Structure ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Synthesis of a rutile-type lead-substituted tin oxide with (110) face was investigated. The characterization was performed by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, infrared spectroscopy, x-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The homogeneous rutile-type lead-substituted tin oxide was obtained until 4.1 mol% of tin was substituted with lead. The surface of obtained oxide had a homogeneously lead-substituted (110) face.

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Synthesis and Characterization of Novel AlF3 Cubes

NANO ◽

10.1142/s179329201550071x ◽

2015 ◽

Vol 10 (05) ◽

pp. 1550071 ◽

Cited By ~ 1

Author(s):

Maoquan Xue ◽

Changsheng Li

Keyword(s):

Electron Microscopy ◽

Synthesis And Characterization ◽

Metal Fluoride ◽

Controlled Synthesis ◽

X Ray ◽

Transmission Electron ◽

Cubic Structure ◽

Synthesis Approach ◽

Scanning Electron

In this paper, regularly shaped AlF 3 particles with cubic structure were successfully synthesized via a solvothermal route. The as-prepared products were characterized by X-ray powder diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results indicated that reaction temperature and time have significant effects on the morphology of the as-prepared products. A possible formation process has also been investigated on the basis of a series of XRD and SEM studies of the product obtained at different conditions. This well-controlled synthesis approach may be extended to fabricate other metal fluoride materials.

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Preparation and Characterization of Nanostructured Hollow MgO Spheres

Materials ◽

10.3390/ma12030537 ◽

2019 ◽

Vol 12 (3) ◽

pp. 537

Author(s):

Jishuo Han ◽

Guohua Li ◽

Lin Yuan

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Shell Thickness ◽

Template Method ◽

X Ray Diffraction ◽

X Ray ◽

Carbon Microsphere ◽

Transmission Electron ◽

Scanning Electron

Nanostructured hollow MgO microspheres were prepared by the template method. First, D-Anhydrous glucose was polymerized by the hydrothermal method to form a template. Second, a colorless solution was obtained by mixing magnesite with hydrochloric acid in a 1:2 proportion and heating in an 80 °C water bath for 2 h. Finally, the template from the first step was placed in the colorless solution, and the resulting precipitate was calcined at 550 °C for 2 h. The phase composition and microstructure of the calcined samples were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD results indicated that the main crystal is periclase. The SEM results indicates that the template carbon microsphere surface is smooth, and the its size is uniform and concentrated in the range of 100–200 nm. The diameters of the samples range from 60 to 90 nm, which is smaller than the size of the carbon microsphere. The TEM results indicates that the sample is hollow with a shell thickness of about 6–10 nm. The specific surface area of the calcined hollow sphere is 59.5 m²·g−1.

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Distrionella coxiana, a new fragilarioid diatom species (Bacillariophyceae) from Tierra del Fuego, Patagonia, Argentina

Plant Ecology and Evolution ◽

10.5091/plecevo.2019.1587 ◽

2019 ◽

Vol 152 (2) ◽

pp. 385-391

Author(s):

Valeria Casa ◽

Gabriela Mataloni ◽

Bart Van de Vijver

Keyword(s):

Typical Feature ◽

Morphological Features ◽

Tierra Del Fuego ◽

New Taxon ◽

Diatom Species ◽

Unique Combination ◽

Diatom Flora ◽

Electron Microscopical ◽

Scanning Electron ◽

Freshwater Diatom

Background and aims – A few years ago, a new survey started of the freshwater diatom flora from peatbogs of Tierra del Fuego (southern Argentina). During this survey, an unknown fragilarioid diatom belonging to the genus Distrionella that could not be identified using the currently available literature was discovered. Methods – Using both Light Microscopical and Scanning Electron Microscopical techniques, the morphology of the unknown Distrionella species has been analysed. The new taxon is properly described, illustrated and compared with all other possible similar Distrionella taxa, known worldwide. Key results – Distrionella coxiana possesses a unique combination of morphological features that excludes conspecificity with all other members of the genus; it is characterized in having narrow, linear valves with small, capitate apices. Transapical ribs, a typical feature of the genus Distrionella, are only weakly developed. One rimoportula is observed close to the apices. Both apices have well-developed apical porefields. The girdle bands bear one complete row of poroids often accompanied by a second, incomplete row of small poroids. Notes on the occurrence and ecology of the new taxon are added.

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Characteristic Morphology and Its Properties of Melt-Crystallized Polyethylene Banded Spherulites on Scanning Electron Microscope

Microscopy and Microanalysis ◽

10.1017/s1431927600028579 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 500-501

Author(s):

Jemyung Park ◽

Kyuyoung Eom ◽

Ohjun Kwon

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Structure Characterization ◽

Etching Technique ◽

Thick Sample ◽

Bulk Specimen ◽

Transmission Electron ◽

Banded Spherulites ◽

Scanning Electron

In spite of commercial importance of polyethylene(PE), morphologies of melt crystallized PE have been rarely studied. Although, it was possible to observe polyethylene microstructure, they were based on the observation performed almost exclusively on thin films which were obtained either by casting samples between glass plates, or by microtoming the materials with transmission electron microscope(TEM). Despite the usefulness of TEM for detailed investigation of the polyethylene, it is not suitable for the structure characterization of the bulk samples, for examples, the characterization of a thick testpiece and commercial products of polyethylene itself. For such bulk specimen or thick sample, scanning electron microscope (SEM) is more useful, if the appropriate and reliable sample preparation method is applied.In this study, we introduce a chemical etching technique for the investigation of melt crystallized polyethylene microstructure by SEM. Especially in this work we studied the characteristic properties and shapes of polyethylene banded spherulite which come from the melt s.

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Characterization of monoclonal IgG cryoglobulins: fine-structural and morphological analysis

Blood ◽

10.1182/blood.v69.2.677.677 ◽

1987 ◽

Vol 69 (2) ◽

pp. 677-681 ◽

Cited By ~ 12

Author(s):

DN Podell ◽

CH Packman ◽

J Maniloff ◽

GN Abraham

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Morphological Analysis ◽

Vascular Occlusion ◽

Molecular Clusters ◽

Morphological Properties ◽

Transmission Electron ◽

Thin Walled ◽

Scanning Electron

Abstract The morphology of the amorphous, gelatinous, and crystalline varieties of monoclonal IgG cryoglobulins was analyzed by light and transmission and scanning electron microscopy. Each cryoglobulin had a characteristic fine structure that correlated with its gross morphology. Transmission electron microscopy showed that the amorphous precipitates were random and disorganized molecular clumps. In contrast, cryogels were thin-walled, well-organized, and hydrated strawlike clusters, whereas cryocrystals formed tightly compacted, highly structured molecular clusters. Crystals that formed in blood produced rouleaux, and analysis by scanning electron microscopy indicated that the crystals could form thick-walled, branching, macromolecular nets that could physically trap cells. The morphological properties provided visual impressions by which cryoglobulins could cause clinical disease secondary to vascular occlusion produced by self- associated IgG cryoglobulin molecules.

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