Role of interfacial interactions to control the extent of wrapping of polymer chains on multi-walled carbon nanotubes

RSC Advances ◽  
2016 ◽  
Vol 6 (48) ◽  
pp. 42334-42346 ◽  
Author(s):  
Suchitra Parija ◽  
Arup R. Bhattacharyya
Keyword(s):  
Polymer Chains ◽  
Electron Microscopic ◽  
Α Phase ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Electron Microscopic Image ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Transmission Electron Microscopic Image

Transmission electron microscopic image of separated MWCNTs (N51L15G5) showing the wrapped polymer chains on the MWCNTs surface, which corresponds to the α-phase of the PP.

Human Endolymphatic Duct: Possible Mechanisms of Endolymph Outflow

1986 ◽  
Vol 95 (4) ◽  
pp. 409-414 ◽  
Author(s):  
Phillip A. Wackym ◽  
Ulla Friberg ◽  
Dan Bagger-Sjöbäck ◽  
Helge Rask-Andersen
Keyword(s):  
Experimental Studies ◽  
Organic Matrix ◽  
Osmotic Gradient ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Endolymphatic Duct ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Normal Human

The ultrastructure of the normal human endolymphatic duct (ED) was observed by transmission electron microscopy. The role of the epithelium, the various regions of the subepithelial space, and vasculature in the resorption of endolymph was morphologically studied in order to generate testable hypotheses of human ED function. These hypothetical mechanisms of endolymph outflow at the level of the ED are 1) a passive transcellular movement of water across the epithelium, driven by an osmotic gradient created by a subepithelial organic matrix; 2) an active transcellular ion exchange with a passive transepithelial outflow of water, which stresses the importance of the dilated lateral intercellular spaces; and 3) an active transcellular vacuolar endolymph outflow, whereby high molecular weight substances are removed by the ED. These mechanisms may be useful in designing experimental studies of the ED and in interpretation of retrospective light microscopic and transmission electron microscopic studies of patients with Meniere's disease.

ELECTRON MICROSCOPY OF QUASICRYSTALS AND THE VALIDITY OF THE TILING APPROACH

1993 ◽  
Vol 07 (06n07) ◽  
pp. 1387-1413 ◽  
Author(s):  
H.-U. NISSEN ◽  
C. BEELI
Keyword(s):  
Image Contrast ◽  
Microscopic Image ◽  
Electron Microscopic ◽  
Structural Interpretation ◽  
Random Tiling ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Electron Microscopic Image ◽  
Microscopic Studies ◽  
Quasicrystal Structure

A review is presented of high-resolution transmission electron microscopic studies on icosahedral, decagonal and dodecagonal quasicrystals executed during the last eight years, especially at ETH Zürich, with special consideration of the use made of tilings for the interpretation of the electron microscopic image contrast. Since the contrast contains information on the projected potential of the quasicrystal structure, the local details of decorated and undecorated tilings can be correlated to the image contrast. These tilings can even be superimposed directly onto the micrographs as an aid in structural interpretation. Also, tilings can directly be constructed by computer on the basis of contrast maxima or minima appearing in the image. These tilings serve to differentiate between quasiperiodic tiling and random tiling quasicrystal structures. Examples of the successful application of these types of tilings in the structural interpretation of electron microscopic observations on quasicrystal alloys are presented.

Foaming of Miscible and Immiscible Polymer Blends

2006 ◽  
Vol 977 ◽  
Author(s):  
Holger Ruckdaeschel ◽  
Julius Rausch ◽  
Jan K.W. Sandler ◽  
Volker Altstaedt ◽  
Holger Schmalz ◽  
...  
Keyword(s):  
Electron Microscopic ◽  
Immiscible Polymer Blends ◽  
Foam Morphology ◽  
Transmission Electron ◽  
Miscible Blends ◽  
Transmission Electron Microscopic ◽  
Detailed Evaluation ◽  
Wide Compositional Range ◽  
Insight Into

AbstractBatch-foaming of miscible, immiscible and compatibilized polymer blend systems over a wide compositional range was carried out using carbon dioxide as a physical blowing agent. The resulting foam morphology was characterized by a detailed evaluation of foam density as well as of the cellular parameters. With regard to multiphase blends, transmission electron microscopic observations further provided a detailed insight into the cell wall morphology. The role of the melt-elongational properties and of the glass transition behavior of the various blend systems on the foaming characteristics was systematically elucidated. While the miscible blends showed a simple additivity behavior with regard to their foaming characteristics and properties, a significant influence of the initial blend morphology is demonstrated for the multiphase blends.

Seasonal Variation of the Intraepithelial Gland in Camel Epididymis with Special Reference to Autophagosome

2019 ◽  
Vol 25 (4) ◽  
pp. 1052-1060 ◽  
Author(s):  
Fatma M. Abdel-Maksoud ◽  
Manal T Hussein ◽  
Abdelraheim Attaai
Keyword(s):  
Seasonal Variation ◽  
Breeding Season ◽  
Reproductive Activity ◽  
Electron Microscopic ◽  
Transmission Electron Microscopic Study ◽  
Nonbreeding Season ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Ultrastructural Characteristics

AbstractThe key role of the epididymis is contributing to sperm storage, maturation, and survival. The epididymis of camel has a unique structure called the intraepithelial gland. The present work aimed to investigate the structure of the epididymal intraepithelial gland with special references to the seasonal variation. The samples were collected from the distal part of the corpus epididymes of completely healthy mature camels (Camelus dromedarius) in the breeding and nonbreeding seasons. Tomato lectin-positive material had been demonstrated within the epididymal spermatozoa. Here, we provide the first transmission electron microscopic study for the intraepithelial gland of camel epididymis detecting the autophagy during the nonbreeding season. The autophagosomes originated from the endoplasmic reticulum, surrounding mitochondria, and located mainly next to the basement membrane. This location is probably valuable for subsequent passing of their contents into the interstitium for possible recycling. The histochemical and ultrastructural characteristics of the gland in the breeding season indicated a hyperactive secretory microenvironment enriched with the glycoprotein-producing machinery, which could be controlled by androgens. The present data suggest that the camel intraepithelial gland has a significant impact on the reproductive activity through their secretory microenvironment during the breeding season. Moreover, it recycles the unused organelles or proteins for reuse or to supply energy under stress conditions in the nonbreeding season.

Electrical, Optical and Structural Properties of Thin SiO2 Films On Si

1987 ◽  
Vol 105 ◽  
Author(s):  
N. M. Ravindra ◽  
O. L. Russo ◽  
D. Fathy ◽  
J. Narayan ◽  
A. R. Heyd ◽  
...  
Keyword(s):  
Breakdown Voltage ◽  
Dielectric Strength ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Current Voltage ◽  
Current Conduction ◽  
Transmission Electron Microscopic ◽  
State Densities ◽  
20 Nm

AbstractBreakdown voltage, static current-voltage, spectroscopic ellipsometry (SE), electrolyte electroreflectance (EER) and high resolution transmission electron microscopic (HRTEM) studies of thermally grown thin films of SiO2 on silicon (800°C - dry) are reported here. The investigation of the electrical properties of these films lead us to suggest the criteria for determining the breakdown voltage of these 20nm thick SiO2 films. The Fowler-Nordheim tunneling contribution to current conduction mechanisms in SiO2 has been considered in evaluating these criteria. SE, EER & HRTEM studies have been performed on SiO2 films of thicknesses in the range of 1–20 nm. These studies lead us to determine the thickness of the non-stoichiometric silicon-rich oxide existing at the Si-SiO2 interface. EER studies show that the relative surface state densities for different film thicknesses can be determined. The role of the transition region in determining the dielectric strength of thin SiO2 films is discussed.

The blister of porphyria cutanea tarda: A Scanning and Transmission Electron Microscopic study

1986 ◽  
Vol 44 ◽  
pp. 334-335
Author(s):  
Veronika Burmeister ◽  
R. Swaminathan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Basement Membrane ◽  
Middle Age ◽  
Porphyria Cutanea Tarda ◽  
Minor Trauma ◽  
Electron Microscopic ◽  
Transmission Electron Microscopic Study ◽  
Transmission Electron ◽  
Transmission Electron Microscopic

Porphyria cutanea tarda (PCT) is a disorder of porphyrin metabolism which occurs most often during middle age. The disease is characterized by excessive production of uroporphyrin which causes photosensitivity and skin eruptions on hands and arms, due to minor trauma and exposure to sunlight. The pathology of the blister is well known, being subepidermal with epidermodermal separation, it is not always absolutely clear, whether the basal lamina is attached to the epidermis or the dermis. The purpose of our investigation was to study the attachment of the basement membrane in the blister by comparing scanning with transmission electron microscopy.

TEM comparison of osmium vs osmium with potassium ferricyanide secondary fixatives and the impact of secondary fixative temperature on tissue preservation/contrast quality

1996 ◽  
Vol 54 ◽  
pp. 910-911
Author(s):  
J. W. Horn ◽  
B. J. Dovey-Hartman ◽  
V. P. Meador
Keyword(s):  
Osmium Tetroxide ◽  
Potassium Ferricyanide ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Microscopic Evaluation ◽  
Cacodylate Buffer ◽  
Transmission Electron Microscopic ◽  
Glutaraldehyde Solution ◽  
Temperature Impact ◽  
The Impact

Osmium tetroxide (OsO4) is a universally used secondary fixative for routine transmission electron microscopic evaluation of biological specimens. Use of OsO4 results in good ultrastructural preservation and electron density but several factors, such as concentration, length of exposure, and temperature, impact overall results. Potassium ferricyanide, an additive used primarily in combination with OsO4, has mainly been used to enhance the contrast of lipids, glycogen, cell membranes, and membranous organelles. The purpose of this project was to compare the secondary fixative solutions, OsO4 vs. OsO4 with potassium ferricyanide, and secondary fixative temperature for determining which combination gives optimal ultrastructural fixation and enhanced organelle staining/contrast.Fresh rat liver samples were diced to ∼1 mm3 blocks, placed into porous processing capsules/baskets, preserved in buffered 2% formaldehyde/2.5% glutaraldehyde solution, and rinsed with 0.12 M cacodylate buffer (pH 7.2). Tissue processing capsules were separated (3 capsules/secondary fixative.solution) and secondarily fixed (table) for 90 minutes. Tissues were buffer rinsed, dehydrated with ascending concentrations of ethanol solutions, infiltrated, and embedded in epoxy resin.

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