Determination of the boundary of the plastic zone in a mineral vein weakened by a three-dimensional hole

1995 ◽  
Vol 74 (4) ◽  
pp. 1120-1123
Author(s):  
N. S. Khapilova
Keyword(s):  
Plastic Zone ◽  
Three Dimensional ◽  
Mineral Vein

Conformation of Ribosomes from Escherichia Coli

1974 ◽  
Vol 32 ◽  
pp. 210-211
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Binding Sites ◽  
Ribosomal Proteins ◽  
Fluorescent Dyes ◽  
Protein Biosynthesis ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Dimensional Structure ◽  
Complete Understanding ◽  
And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

scholarly journals Meso-Scale Transmission Electron Microscope Tomography Applied for Wax Distribution in Toner Particles

2013 ◽  
Vol 19 (S5) ◽  
pp. 58-61 ◽  
Author(s):  
Mino Yang ◽  
Jun-Ho Lee ◽  
Hee-Goo Kim ◽  
Euna Kim ◽  
Young-Nam Kwon ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Three Dimensional ◽  
Chromatic Aberration ◽  
Laser Printer ◽  
Medium Voltage ◽  
Transmission Electron ◽  
Z Contrast ◽  
Contrast Image

AbstractDistribution of wax in laser printer toner was observed using an ultra-high-voltage (UHV) and a medium-voltage transmission electron microscope (TEM). As the radius of the wax spans a hundred to greater than a thousand nanometers, its three-dimensional recognition via TEM requires large depth of focus (DOF) for a volumetric specimen. A tomogram with a series of the captured images would allow the determination of their spatial distribution. In this study, bright-field (BF) images acquired with UHV-TEM at a high tilt angle prevented the construction of the tomogram. Conversely, the Z-contrast images acquired by the medium-voltage TEM produced a successful tomogram. The spatial resolution for both is discussed, illustrating that the image degradation was primarily caused by beam divergence of the Z-contrast image and the combination of DOF and chromatic aberration of the BF image from the UHV-TEM.

Ab Initio Determination of a New Complex Structure (55 Non-Hydrogen Atoms) from Synchrotron Powder Data: An Uncommon Nickel Succinate, Ni7(C4H4O4)4(OH)6(H2O)3•7H2O

2004 ◽  
Vol 443-444 ◽  
pp. 333-336
Author(s):  
N. Guillou ◽  
C. Livage ◽  
W. van Beek ◽  
G. Férey
Keyword(s):  
Ab Initio ◽  
Complex Structure ◽  
Three Dimensional ◽  
Free Water ◽  
Hydrogen Atoms ◽  
Monoclinic System ◽  
Synchrotron Powder Diffraction ◽  
Chloride Hexahydrate ◽  
Autogenous Pressure

Ni7(C4H4O4)4(OH)6(H2O)3. 7H2O, a new layered nickel(II) succinate, was prepared hydrothermally (180°C, 48 h, autogenous pressure) from a 1:1.5:4.1:120 mixture of nickel (II) chloride hexahydrate, succinic acid, potassium hydroxide and water. It crystallizes in the monoclinic system (space group P21/c, Z = 4) with the following parameters a = 7.8597(1) Å, b = 18.8154(3)Å, c = 23.4377(4) Å,ϐ = 92.0288(9)°, and V = 3463.9(2) Å3. Its structure, which contains 55 non-hydrogen atoms, was solved ab initio from synchrotron powder diffraction data. It can be described from hybrid organic-inorganic layers, constructed from nickel oxide corrugated chains. These chains are built up from NiO6hexameric units connected via a seventh octahedron. Half of the succinates decorate the chains, and the others connect them to form the layers. The three dimensional arrangement is ensured by hydrogen bonds directly between two adjacent layers and via free water molecules.

Sign in / Sign up

Export Citation Format

Share Document