Characterization of structure evolution of Ti–O clusters in molten iron

Several members of the Protoparvovirus genus, capable of infecting humans, have been recently discovered, including cutavirus (CuV) and tusavirus (TuV). To begin the characterization of these viruses, we have used cryo-electron microscopy and image reconstruction to determine their capsid structures to ~2.9 Å resolution, and glycan array and cell-based assays to identify glycans utilized for cellular entry. Structural comparisons show that the CuV and TuV capsids share common features with other parvoviruses, including an eight-stranded anti-parallel β-barrel, depressions at the icosahedral 2-fold and surrounding the 5-fold axes, and a channel at the 5-fold axes. However, the viruses exhibit significant topological differences in their viral protein surface loops. These result in three separated 3-fold protrusions, similar to the bufaviruses also infecting humans, suggesting a host-driven structure evolution. The surface loops contain residues involved in receptor binding, cellular trafficking, and antigenic reactivity in other parvoviruses. In addition, terminal sialic acid was identified as the glycan potentially utilized by both CuV and TuV for cellular entry, with TuV showing additional recognition of poly-sialic acid and sialylated Lewis X (sLeXLeXLeX) motifs reported to be upregulated in neurotropic and cancer cells, respectively. These structures provide a platform for annotating the cellular interactions of these human pathogens.

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In-Situ X-Ray Characterization of Fiber Structure during Melt Spinning

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892500800300302 ◽

2008 ◽

Vol 3 (3) ◽

pp. 155892500800300 ◽

Cited By ~ 6

Author(s):

Michael S. Ellison ◽

Paulo E. Lopes ◽

William T. Pennington

Keyword(s):

Melt Spinning ◽

Simultaneous Detection ◽

Polymer Melt ◽

Polymer Chains ◽

Degree Of Crystallinity ◽

Structure Evolution ◽

X Ray ◽

Spinning Process

The properties of a polymer are strongly influenced by its morphology. In the case of fibers from semi-crystalline polymers this consists of the degree of crystallinity, the spacing and alignment of the crystalline regions, and molecular orientation of the polymer chains in the amorphous regions. Information on crystallinity and orientation can be obtained from X-ray analysis. In-situ X-ray characterization of a polymer during the melt spinning process is a major source of information about the effects of material characteristics and processing conditions upon structure evolution along the spinline, and the final structure and properties of the end product. We have recently designed and installed an X-ray system capable of in-situ analysis during polymer melt spinning. To the best of our knowledge this system is unique in its capabilities for the simultaneous detection of wide angle and small angle X-ray scattering (WAXS and SAXS, respectively), its use of a conventional laboratory radiation source, its vertical mobility along the spinline, and its ability to simulate a semi-industrial environment. Setup, operation and demonstration of the capabilities of this system is presented herein as applied to the characterization of the melt spinning of isotactic poly(propylene). Crystallinity and crystalline orientation calculated from WAXS patterns, and lamellar long period calculated from SAXS patterns, were obtained during melt spinning of the polymer along the spinline.

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Liquid structure evolution of molten iron in blast furnace hearth

Metallurgical Research & Technology ◽

10.1051/metal/2019035 ◽

2019 ◽

Vol 116 (6) ◽

pp. 601

Author(s):

Yong Deng ◽

Kexin Jiao ◽

Jianliang Zhang

Keyword(s):

Distribution Function ◽

Blast Furnace ◽

Carbon Content ◽

Interfacial Reaction ◽

Structure Factor ◽

Physical Property ◽

Liquid Structure ◽

Molten Iron ◽

Structure Evolution ◽

X Ray

The iron-carbon interfacial reaction between molten iron and carbon brick was carried out to simulate the working condition of blast furnace (BF) hearth. The carbon content in molten iron after the reaction was detected to be 5.0% which was almost saturated. XRD and SEM-EDS were conducted on the surface of polished rectangle iron before and after iron-carbon interfacial reaction. Fine striped graphite was observed in iron before iron-carbon interfacial reaction, a large amount of flake-like graphite was observed in iron after iron-carbon interfacial reaction. As a structure-sensitive physical property, the viscosity of molten iron was the macroscopic expression of its liquid structure. The liquid structure of molten iron (Fe-4.5%C, Fe-5.0%C) was measured through a high temperature X-ray diffractometer. The X-ray original diffraction intensity, the structure factor, the pair distribution function, the radial distribution function, and the main parameters of molten iron were obtained through the calculation. The presence of pre-peak in the structure factor indicated that there was a medium-range order in molten iron, some compounds or cluster of atoms might exist in molten iron, the structure model of atoms in liquid Fe-4.5%C was predicted through the structure parameters. The increase of carbon content after iron-carbon interfacial reaction was the essential reason for liquid structure evolution of molten iron in hearth.

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Development of the MFPR/R code for characterization of the rim zone and high burnup structure evolution in UO2 fuel pellets

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2019.01.055 ◽

2019 ◽

Vol 517 ◽

pp. 214-224 ◽

Cited By ~ 2

Author(s):

V.I. Tarasov ◽

P.V. Polovnikov ◽

V.E. Shestak ◽

M.S. Veshchunov

Keyword(s):

Structure Evolution ◽

Fuel Pellets ◽

High Burnup

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Characterization of Structure Evolution in Aged Al2O3/SiC Composite Refractories by Electron Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927610060824 ◽

2010 ◽

Vol 16 (S2) ◽

pp. 946-947

Author(s):

V Solomon ◽

K Peters ◽

B Hetzel ◽

T Wagner

Keyword(s):

Electron Microscopy ◽

Structure Evolution

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

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Applying Social Network Analysis Techniques to Community-Driven Libre Software Projects

Software Applications ◽

10.4018/978-1-60566-060-8.ch112 ◽

2009 ◽

pp. 1883-1905

Author(s):

Luis López-Fernández ◽

Gregorio Robles ◽

Jesus M. Gonzalez-Barahona ◽

Israel Herraiz

Keyword(s):

Network Architecture ◽

Knowledge Exchange ◽

Relevant Information ◽

Structure Evolution ◽

Collaboration Network ◽

Software Projects ◽

The Social ◽

Libre Software ◽

Available Information

Source code management repositories of large, long-lived libre (free, open source) software projects can be a source of valuable data about the organizational structure, evolution, and knowledge exchange in the corresponding development communities. Unfortunately, the sheer volume of the available information renders it almost unusable without applying methodologies which highlight the relevant information for a given aspect of the project. Such methodology is proposed in this article, based on well known concepts from the social networks analysis field, which can be used to study the relationships among developers and how they collaborate in different parts of a project. It is also applied to data mined from some well known projects (Apache, GNOME, and KDE), focusing on the characterization of their collaboration network architecture. These cases help to understand the potentials of the methodology and how it is applied, but also shows some relevant results which open new paths in the understanding of the informal organization of libre software development communities.

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