Direct evidence of uneven 
dxz
 and 
dyz
 orbital occupation in the superconducting state of iron pnictide

Angular-dependent torque measurements have been performed on the electron doped iron-pnictide superconductors BaFe[Formula: see text]NixAs2 with series of Ni concentrations. In the superconducting state, an irreversibility, as the evidence for the presence of vortex, is observed between the torque measured with increasing and decreasing angle. Our results in underdoped samples [Formula: see text] show that the irreversible torque signal survives up to a temperature [Formula: see text] well above the superconducting transition temperature [Formula: see text], suggesting the existence of superconducting vortices above [Formula: see text], which is likely to originate from superconducting fluctuations.

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Quasi-particle dispersion and density of states in superconducting state of iron pnictide system

Materials Express ◽

10.1166/mex.2014.1186 ◽

2014 ◽

Vol 4 (5) ◽

pp. 400-414 ◽

Cited By ~ 2

Author(s):

Luxmi Rani ◽

. Ajay

Keyword(s):

Density Of States ◽

Superconducting State ◽

Particle Dispersion ◽

Quasi Particle ◽

Iron Pnictide

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The Immuno-Electron Microscopic Localization of the Mo-Fe Protein Component of Nitrogenase in Cells of Azotobacter Vinelandii

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073313 ◽

1973 ◽

Vol 31 ◽

pp. 574-575

Author(s):

J. T. Stasny ◽

R. C. Burns ◽

R. W. F. Hardy

Keyword(s):

Cellular Localization ◽

Direct Evidence ◽

Azotobacter Vinelandii ◽

Intracellular Localization ◽

Protein Component ◽

Electron Microscopic ◽

Thin Sections ◽

Fe Protein ◽

Intracytoplasmic Membranes

Structure-functlon studies of biological N2-fixation have correlated the presence of the enzyme nitrogenase with increased numbers of intracytoplasmic membranes in Azotobacter. However no direct evidence has been provided for the internal cellular localization of any nitrogenase. Recent advances concerned with the crystallizatiorTand the electron microscopic characterization of the Mo-Fe protein component of Azotobacter nitrogenase, prompted the use of this purified protein to obtain antibodies (Ab) to be conjugated to electron dense markers for the intracellular localization of the protein by electron microscopy. The present study describes the use of ferritin conjugated to goat antitMo-Fe protein immunoglobulin (IgG) and the observations following its topical application to thin sections of N2-grown Azotobacter.

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Structural similarity of ribosomes from E. coli and A. salina

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082078 ◽

1978 ◽

Vol 36 (2) ◽

pp. 242-243

Author(s):

M. Boublik ◽

R.M. Wydro ◽

W. Hellmann ◽

F. Jenkins

Keyword(s):

Ribosomal Proteins ◽

Direct Evidence ◽

Structural Similarity ◽

Carbon Support ◽

Artemia Salina ◽

Uranyl Acetate ◽

Biological Assays ◽

E Coli ◽

And Function ◽

Fine Carbon

Ribosomes are ribonucleoprotein particles necessary for processing the genetic information of mRNA into proteins. Analogy in composition and function of ribosomes from diverse species, established by biochemical and biological assays, implies their structural similarity. Direct evidence obtained by electron microscopy seems to be of increasing relevance in understanding the structure of ribosomes and the mechanism of their role in protein synthesis.The extent of the structural homology between prokaryotic and eukaryotic ribosomes has been studied on ribosomes of Escherichia coli (E.c.) and Artemia salina (A.s.). Despite the established differences in size and in the amount and proportion of ribosomal proteins and RNAs both types of ribosomes show an overall similarity. The monosomes (stained with 0.5% aqueous uranyl acetate and deposited on a fine carbon support) appear in the electron micrographs as round particles with a diameter of approximately 225Å for the 70S E.c. (Fig. 1) and 260Å for the 80S A.s. monosome (Fig. 2).

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