The use of sample positioning to control defect creation by oxygen plasma in isotopically labelled bilayer graphene membranes

Determination of the mass concentration of quartz in small biopsy specimens for clinical diagnostic purposes often cannot be performed by x-ray diffraction and light microscopy. A technique utilizing transmission electron microscopy (TEM) was used to determine the quartz concentration in a human lung specimen taken from a patient suspected of having silicosis.The sample was prepared for examination by low temperature incineration in an oxygen plasma. The inorganic residue was suspended in 0.5 percent Parlodion in amyl acetate. Grids were coated with the sample suspension and subsequently shadowed with a thin film of carbon. Standard quartz particles were prepared in a similar manner.

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Point defects in turbostratic stacked bilayer graphene

Nanoscale ◽

10.1039/c7nr03879h ◽

2017 ◽

Vol 9 (36) ◽

pp. 13725-13730 ◽

Cited By ~ 3

Author(s):

Chuncheng Gong ◽

Sungwoo Lee ◽

Suklyun Hong ◽

Euijoon Yoon ◽

Gun-Do Lee ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Point Defects ◽

Density Functional ◽

Tight Binding ◽

Bilayer Graphene ◽

Dynamics Simulation ◽

Functional Theory ◽

Transmission Electron ◽

Aberration Corrected

The point defects in turbostratic bilayer graphene are characterized using aberration-corrected transmission electron microscopy, density functional theory, and tight-binding molecular dynamics simulation.

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Direct Mapping of Stacking Structure in Rotated Bilayer Graphene Using Aberration-corrected Transmission Electron Microscopy

Microscopy and Microanalysis ◽

10.1017/s143192761300812x ◽

2013 ◽

Vol 19 (S2) ◽

pp. 1226-1227

Author(s):

J.M. Yuk ◽

H.Y. Jeong ◽

N.Y. Kim ◽

M.J. Lee ◽

J.Y. Lee ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Bilayer Graphene ◽

Direct Mapping ◽

Transmission Electron ◽

Stacking Structure ◽

Aberration Corrected

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

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Techniques for Transmission Electron Microscopy of Fiber-Matrix Interfaces in Aluminum Alloy-Boron Composites by Ion Erosio

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065079 ◽

1971 ◽

Vol 29 ◽

pp. 204-205

Author(s):

G. G. Shaw

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Aluminum Alloy ◽

Electron Beam ◽

Pure Aluminum ◽

Ion Milling ◽

Transmission Electron ◽

Fiber Matrix ◽

Ion Erosion ◽

Row Of Fibers

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.

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Direct Observation of Heat Exchanger Deposits by Cross Sectioning

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061835 ◽

1967 ◽

Vol 25 ◽

pp. 364-365

Author(s):

R. W. Anderson ◽

D. L. Senecal

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Heat Exchanger ◽

Direct Observation ◽

Cross Sections ◽

Preparation Method ◽

Specimen Preparation ◽

Flowing Water ◽

Transmission Electron ◽

Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

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Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052584 ◽

1974 ◽

Vol 32 ◽

pp. 514-515

Author(s):

S. Fujishiro

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Transmission Electron Microscopy ◽

Tensile Strength ◽

Mechanical Processing ◽

Ray Method ◽

X Ray ◽

Transmission Electron ◽

Water Quench ◽

Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081279 ◽

1978 ◽

Vol 36 (2) ◽

pp. 82-83 ◽

Cited By ~ 1

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).

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Comparative Microstructures of Ion Milled and Electrochemically Thinned Composite Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052742 ◽

1974 ◽

Vol 32 ◽

pp. 546-547

Author(s):

R.R. Russell

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Composite Materials ◽

Great Difficulty ◽

Ion Milling ◽

Transmission Electron ◽

Ion Damage ◽

Intermetallic Composite

Transmission electron microscopy of metallic/intermetallic composite materials is most challenging since the microscopist typically has great difficulty preparing specimens with uniform electron thin areas in adjacent phases. The application of ion milling for thinning foils from such materials has been quite effective. Although composite specimens prepared by ion milling have yielded much microstructural information, this technique has some inherent drawbacks such as the possible generation of ion damage near sample surfaces.

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Maytansine-Induced Mitotic Arrest in Human Lymphoblasts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079747 ◽

1977 ◽

Vol 35 ◽

pp. 460-461

Author(s):

Tai-Te Chao ◽

John Sullivan ◽

Awtar Krishan

Keyword(s):

Electron Microscopy ◽

Cell Cycle ◽

Transmission Electron Microscopy ◽

Tubulin Polymerization ◽

Vinca Alkaloids ◽

Antimitotic Activity ◽

Transmission Electron ◽

Flow Microfluorometry ◽

Brain Tubulin

Maytansine, a novel ansa macrolide (1), has potent anti-tumor and antimitotic activity (2, 3). It blocks cell cycle traverse in mitosis with resultant accumulation of metaphase cells (4). Inhibition of brain tubulin polymerization in vitro by maytansine has also been reported (3). The C-mitotic effect of this drug is similar to that of the well known Vinca- alkaloids, vinblastine and vincristine. This study was carried out to examine the effects of maytansine on the cell cycle traverse and the fine struc- I ture of human lymphoblasts.Log-phase cultures of CCRF-CEM human lymphoblasts were exposed to maytansine concentrations from 10-6 M to 10-10 M for 18 hrs. Aliquots of cells were removed for cell cycle analysis by flow microfluorometry (FMF) (5) and also processed for transmission electron microscopy (TEM). FMF analysis of cells treated with 10-8 M maytansine showed a reduction in the number of G1 cells and a corresponding build-up of cells with G2/M DNA content.

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