Complementary mass spectrometric approaches and scanning electron microscopy to study the structural stability of polyurethane tunneled dialysis catheters after exposure to ethanol solutions

2013 ◽  
Vol 27 (21) ◽  
pp. 2343-2354 ◽  
Author(s):  
Nizar Msakni ◽  
Marie-Josèphe Galmier ◽  
Marie-Joëlle Couret ◽  
Claire Szczepaniak ◽  
Bernadette Bouchon ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Structural Stability ◽  
Mass Spectrometric ◽  
Scanning Electron

scholarly journals Hydrothermal Synthesis, Characterization, andIn VitroDrug Adsorption Studies of Some Nano-BioMOFs

2016 ◽  
Vol 2016 ◽  
pp. 1-10
Author(s):  
Tabinda Sattar ◽  
Muhammad Athar ◽  
Muhammad Najamul Haq
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Performance ◽  
Slow Release ◽  
Mass Spectrometric ◽  
Nanosized Materials ◽  
Drug Adsorption ◽  
Molecular Masses ◽  
Scanning Electron

Three new nano-bioMOFs (NBMOFs) (copper serinate, copper prolinate, and copper threoninate) have been hydrothermally synthesized and characterized by the scanning electron microscopy (SEM). Molecular masses of these nanomaterials have been obtained by mass spectrometric studies. Successfulin vitrodrug adsorption of rosuvastatin drug has been carried out in these three nanosized materials. The amount of rosuvastatin adsorbed in these materials and its slow release after intervals have been monitored by the high performance liquid chromatography (HPLC). TGA and PXRD spectra of all these materials in pure form and after rosuvastatin adsorption have also been recorded to elaborate the phenomenon ofin vitrodrug adsorption in these materials.

scholarly journals The first find of carbon nano- and microtubes and graphite mi- croflakes in carbonate “stone pipes” (island of Crete, Greece)

2020 ◽  
Vol 1 (1) ◽  
pp. 118-132
Author(s):  
Mikhail Yur’evich POVARENNYKH ◽  
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Mediterranean Region ◽  
Mass Spectrometric ◽  
Optical Polarization ◽  
Crete Island ◽  
Explosive Reaction ◽  
Scanning Electron ◽  
Comprehensive Study

Relevance of the work. After finding carbon nanotubes in the so-called silicate “stone pipes” of Dzharakuduk (Uzbekistan) in 2016, we quickly began to accumulate material about discovering carbon nanominerals in similar objects in Kazakhstan, Israel, and India. And after a similar find on the island of Crete (but in carbonate “stone pipes”), it became possible to conduct some generalization for the Mediterranean region. Purpose of the work: identification of the features of the development of carbon nano- and micromineralization in the carbonate “stone pipes” of the island of Crete in comparison with previously known samples from silicate “stone pipes”. Methodology. The samples selected by the authors were studied using optical polarization (ATAMI microscope) and scanning electron microscopy with microdiffraction (SEM LEO SUPRA 50V), differential thermal analysis with mass spectrometric termination (DTA + TG + MS). Results. In the pores and caverns of pyro- and shock-metamorphosed organogenic calcite limestones in the outcrop on the coast of northern Crete (near Malia, Crete, Greece), some fibrous-diverse aggregates of carbon nano- and microminerals (carbon multilayer nano- and microtubes, as well as microflakes of multilayer “graphenes”externally replaced by graphite) with carbonate “stone pipes” almost completely cut off by sea erosion. Conclusions. The first comprehensive study of carbon nano- and micromineralization in the carbonate “stone pipes” of Crete Island allows us to conclude that they are formed as a result of the explosive reaction of silanes that were part of the primary hydrocarbon-like fluid with an aqueous-oxygen atmosphere below the earth’s surface at high temperatures (T> 1250 ° C) and pressure (P> 40 Pa).

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

Spontaneous Cataract in Nude Athymic Mice

1977 ◽  
Vol 35 ◽  
pp. 512-513
Author(s):  
Ronald H. Bradley ◽  
R. S. Berk ◽  
L. D. Hazlett
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Nude Mouse ◽  
Cellular Immunity ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Athymic Mice ◽  
Transmission Microscopy ◽  
Mouse Lens ◽  
Scanning Electron

The nude mouse is a hairless mutant (homozygous for the mutation nude, nu/nu), which is born lacking a thymus and possesses a severe defect in cellular immunity. Spontaneous unilateral cataractous lesions were noted (during ocular examination using a stereomicroscope at 40X) in 14 of a series of 60 animals (20%). This transmission and scanning microscopic study characterizes the morphology of this cataract and contrasts these data with normal nude mouse lens.All animals were sacrificed by an ether overdose. Eyes were enucleated and immersed in a mixed fixative (1% osmium tetroxide and 6% glutaraldehyde in Sorenson's phosphate buffer pH 7.4 at 0-4°C) for 3 hours, dehydrated in graded ethanols and embedded in Epon-Araldite for transmission microscopy. Specimens for scanning electron microscopy were fixed similarly, dehydrated in graded ethanols, then to graded changes of Freon 113 and ethanol to 100% Freon 113 and critically point dried in a Bomar critical point dryer using Freon 13 as the transition fluid.

Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

1971 ◽  
Vol 29 ◽  
pp. 410-411 ◽  
Author(s):  
Jane A. Westfall ◽  
S. Yamataka ◽  
Paul D. Enos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Osmium Tetroxide ◽  
External Surface ◽  
Three Dimensional ◽  
Surface Structures ◽  
Transmission Microscopy ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

Microbulldozing and Microchiseling

1969 ◽  
Vol 27 ◽  
pp. 134-135
Author(s):  
J.N. Ramsey ◽  
D.P. Cameron ◽  
F.W. Schneider
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Material Handling ◽  
Microprobe Analysis ◽  
Foreign Matter ◽  
Specific Location ◽  
Potential Problems ◽  
Knoop Indenter ◽  
Scanning Electron ◽  
Microhardness Tester

As computer components become smaller the analytical methods used to examine them and the material handling techniques must become more sensitive, and more sophisticated. We have used microbulldozing and microchiseling in conjunction with scanning electron microscopy, replica electron microscopy, and microprobe analysis for studying actual and potential problems with developmental and pilot line devices. Foreign matter, corrosion, etc, in specific locations are mechanically loosened from their substrates and removed by “extraction replication,” and examined in the appropriate instrument. The mechanical loosening is done in a controlled manner by using a microhardness tester—we use the attachment designed for our Reichert metallograph. The working tool is a pyramid shaped diamond (a Knoop indenter) which can be pushed into the specimen with a controlled pressure and in a specific location.

A New Image Processing Technique for STEM

1974 ◽  
Vol 32 ◽  
pp. 432-433
Author(s):  
Yasushi Kokubo ◽  
Hirotami Koike ◽  
Teruo Someya
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Elastic Scattering ◽  
Field Emission ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Energy Analyzer ◽  
Scanning Microscope ◽  
Scanning Electron

One of the advantages of scanning electron microscopy is the capability for processing the image contrast, i.e., the image processing technique. Crewe et al were the first to apply this technique to a field emission scanning microscope and show images of individual atoms. They obtained a contrast which depended exclusively on the atomic numbers of specimen elements (Zcontrast), by displaying the images treated with the intensity ratio of elastically scattered to inelastically scattered electrons. The elastic scattering electrons were extracted by a solid detector and inelastic scattering electrons by an energy analyzer. We noted, however, that there is a possibility of the same contrast being obtained only by using an annular-type solid detector consisting of multiple concentric detector elements.

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