Elastic Properties of Carbon-Based Nanoscopic Structures

2019 ◽  
pp. 115-139
Author(s):  
Esmaeal Ghavanloo ◽  
Hashem Rafii-Tabar ◽  
Seyed Ahmad Fazelzadeh
Keyword(s):  
Elastic Properties ◽  
Carbon Based

SEM Cold Stage Techniques for the Observation of Vegetative and Floral Apices of Oat (Avena sativa L.) Plants

1977 ◽  
Vol 35 ◽  
pp. 590-591
Author(s):  
B. K. Kirchoff ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Critical Point ◽  
Avena Sativa ◽  
Substantial Improvement ◽  
Fresh Tissue ◽  
Cold Stage ◽  
Critical Point Drying ◽  
Almost All ◽  
Cell Collapse ◽  
Conductive Paint ◽  
Carbon Based

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.

Electron Microscopy and image reconstruction reveal the structural basis for spectrin's elastic properties

1992 ◽  
Vol 50 (1) ◽  
pp. 510-511
Author(s):  
Amy M. McGough ◽  
Robert Josephs
Keyword(s):  
Electron Microscopy ◽  
Elastic Properties ◽  
Conformational Changes ◽  
Quaternary Structure ◽  
Three Dimensional ◽  
Membrane Skeleton ◽  
Projection Algorithm ◽  
Structural Basis ◽  
Iterative Approximation ◽  
Membrane Skeletons

The remarkable deformability of the erythrocyte derives in large part from the elastic properties of spectrin, the major component of the membrane skeleton. It is generally accepted that spectrin's elasticity arises from marked conformational changes which include variations in its overall length (1). In this work the structure of spectrin in partially expanded membrane skeletons was studied by electron microscopy to determine the molecular basis for spectrin's elastic properties. Spectrin molecules were analysed with respect to three features: length, conformation, and quaternary structure. The results of these studies lead to a model of how spectrin mediates the elastic deformation of the erythrocyte.Membrane skeletons were isolated from erythrocyte membrane ghosts, negatively stained, and examined by transmission electron microscopy (2). Particle lengths and end-to-end distances were measured from enlarged prints using the computer program MACMEASURE. Spectrin conformation (straightness) was assessed by calculating the particles’ correlation length by iterative approximation (3). Digitised spectrin images were correlation averaged or Fourier filtered to improve their signal-to-noise ratios. Three-dimensional reconstructions were performed using a suite of programs which were based on the filtered back-projection algorithm and executed on a cluster of Microvax 3200 workstations (4).

The buckling of thin EM specimens

1990 ◽  
Vol 48 (4) ◽  
pp. 850-851
Author(s):  
A.R. Thölén
Keyword(s):  
Electron Microscope ◽  
Elastic Properties ◽  
Crystal Surface ◽  
Specimen Surface ◽  
Radius Of Curvature ◽  
Thin Foils ◽  
Thin Electron ◽  
Regular Patterns

Thin electron microscope specimens often contain irregular bend contours (Figs. 1-3). Very regular bend patterns have, however, been observed around holes in some ion-milled specimens. The purpose of this investigation is twofold. Firstly, to find the geometry of bent specimens and the elastic properties of extremely thin foils and secondly, to obtain more information about the background to the observed regular patterns.The specimen surface is described by z = f(x,y,p), where p is a parameter, eg. the radius of curvature of a sphere. The beam is entering along the z—direction, which coincides with the foil normal, FN, of the undisturbed crystal surface (z = 0). We have here used FN = [001]. Furthermore some low indexed reflections are chosen around the pole FN and in our fcc crystal the following g-vectors are selected:

Stable production of platform chemicals from the continuous hydrodeoxygenation of a raw bio-oil using enhanced carbon-based catalysts

2020 ◽  
Author(s):  
Idoia Hita ◽  
Tomas Cordero-Lanzac ◽  
Francisco J. Garcia-Mateos ◽  
Jose Rodriguez-Mirasol ◽  
Tomas Cordero ◽  
...  
Keyword(s):  
Platform Chemicals ◽  
Stable Production ◽  
Bio Oil ◽  
Carbon Based

Stable production of platform chemicals from the continuous hydrodeoxygenation of a raw bio-oil using enhanced carbon-based catalysts

2020 ◽  
Author(s):  
Idoia Hita ◽  
Tomas Cordero-Lanzac ◽  
Francisco J. Garcia-Mateos ◽  
Jose Rodriguez-Mirasol ◽  
Tomas Cordero ◽  
...  
Keyword(s):  
Platform Chemicals ◽  
Stable Production ◽  
Bio Oil ◽  
Carbon Based

The Hydrostatic Pressure Effect on Elastic Properties of B2-Phase Single Crystals Ti50Ni48Fe2and Ti50Ni45Fe5Alloys

1995 ◽  
Vol 05 (C8) ◽  
pp. C8-729-C8-734
Author(s):  
A.I. Lotkov ◽  
V.P. Lapshin ◽  
V.A. Goncharova ◽  
H.V Chernysheva ◽  
V.N. Grishkov ◽  
...  
Keyword(s):  
Hydrostatic Pressure ◽  
Single Crystals ◽  
Elastic Properties ◽  
Pressure Effect ◽  
B2 Phase

Elastic properties of solids at high pressure

2015 ◽  
Vol 185 (11) ◽  
pp. 1215-1224 ◽  
Author(s):  
Yurii Kh. Vekilov ◽  
Oleg M. Krasil'nikov ◽  
Andrei V. Lugovskoy
Keyword(s):  
High Pressure ◽  
Elastic Properties
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