Creating Edge Sites within the Basal Plane of a MoS2 Catalyst for Substantially Enhanced Hydrodeoxygenation Activity

Natural Brucite (Mg(OH)2) decomposes on heating to form magnesium oxide (MgO) having its cubic ﹛110﹜ and ﹛111﹜ planes respectively parallel to the prism and basal planes of the hexagonal brucite lattice. Although the crystal-lographic relation between the parent brucite crystal and the resulting mag-nesium oxide crystallites is well known, the exact mechanism by which the reaction proceeds is still a matter of controversy. Goodman described the decomposition as an initial shrinkage in the brucite basal plane allowing magnesium ions to shift their original sites to the required magnesium oxide positions followed by a collapse of the planes along the original <0001> direction of the brucite crystal. He noted that the (110) diffraction spots of brucite immediately shifted to the positions required for the (220) reflections of magnesium oxide. Gordon observed separate diffraction spots for the (110) brucite and (220) magnesium oxide planes. The positions of the (110) and (100) brucite never changed but only diminished in intensity while the (220) planes of magnesium shifted from a value larger than the listed ASTM d spacing to the predicted value as the decomposition progressed.

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The stability of dislocation networks under various oxygen-doping conditions in superconducting Bi2Sr2CaCu2Oy single crystals and their influence on the flux pinning properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171742 ◽

1994 ◽

Vol 52 ◽

pp. 802-803

Author(s):

Y. Feng ◽

X. Y. Cai ◽

R. J. Kelley ◽

D. C. Larbalestier

Keyword(s):

Single Crystals ◽

Oxygen Content ◽

Basal Plane ◽

Flux Pinning ◽

Pinning Centers ◽

Before And After ◽

Anomalous Peak ◽

Basal Plane Dislocation ◽

The Stability ◽

Further Development

The issue of strong flux pinning is crucial to the further development of high critical current density Bi-Sr-Ca-Cu-O (BSCCO) superconductors in conductor-like applications, yet the pinning mechanisms are still much debated. Anomalous peaks in the M-H (magnetization vs. magnetic field) loops are commonly observed in Bi2Sr2CaCu2Oy (Bi-2212) single crystals. Oxygen vacancies may be effective flux pinning centers in BSCCO, as has been found in YBCO. However, it has also been proposed that basal-plane dislocation networks also act as effective pinning centers. Yang et al. proposed that the characteristic scale of the basal-plane dislocation networksmay strongly depend on oxygen content and the anomalous peak in the M-H loop at ˜20-30K may be due tothe flux pinning of decoupled two-dimensional pancake vortices by the dislocation networks. In light of this, we have performed an insitu observation on the dislocation networks precisely at the same region before and after annealing in air, vacuumand oxygen, in order to verify whether the dislocation networks change with varying oxygen content Inall cases, we have not found any noticeable changes in dislocation structure, regardless of the drastic changes in Tc and the anomalous magnetization. Therefore, it does not appear that the anomalous peak in the M-H loops is controlled by the basal-plane dislocation networks.

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Microstructure and Physical Properties of Clay-Polymer Composites

MRS Proceedings ◽

10.1557/proc-628-cc11.14 ◽

2000 ◽

Vol 628 ◽

Author(s):

T.N. Blanton ◽

D. Majumdar ◽

S.M. Melpolder

Keyword(s):

Composite Materials ◽

Physical Properties ◽

Polymer Composites ◽

Basal Plane ◽

X Ray Diffraction ◽

X Ray ◽

Layered Clay

ABSTRACTClay-polymer nanoparticulate composite materials are evaluated by the X-ray diffraction technique. The basal plane spacing provided information about the degree of intercalation and exfoliation of the 2: 1 layered clay structure. Both intercalation and exfoliation are controlled by the identity of the polymer and the clay:polymer ratio.

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Electrochemistry of the Basal Plane versus Edge Plane of Graphite Revisited

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.9b01010 ◽

2019 ◽

Vol 123 (18) ◽

pp. 11677-11685 ◽

Cited By ~ 7

Author(s):

Matěj Velický ◽

Peter S. Toth ◽

Colin R. Woods ◽

Kostya S. Novoselov ◽

Robert A. W. Dryfe

Keyword(s):

Basal Plane ◽

Plane Versus

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Bridge Sulfur Vacancies in MoS2 Catalyst for Reverse Water Gas Shift: A First-Principles Study

Applied Surface Science ◽

10.1016/j.apsusc.2021.149925 ◽

2021 ◽

pp. 149925

Author(s):

Hai-Yan Su ◽

Keju Sun ◽

Jin-Xun Liu ◽

Xiufang Ma ◽

Minzhen Jian ◽

...

Keyword(s):

First Principles ◽

Water Gas Shift ◽

First Principles Study ◽

Reverse Water Gas Shift ◽

Water Gas ◽

Mos2 Catalyst

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Characterization of microbial antifreeze protein with intermediate activity suggests that a bound-water network is essential for hyperactivity

Scientific Reports ◽

10.1038/s41598-021-85559-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

N. M.-Mofiz Uddin Khan ◽

Tatsuya Arai ◽

Sakae Tsuda ◽

Hidemasa Kondo

Keyword(s):

Crystal Structure ◽

Basal Plane ◽

Molecular Mechanisms ◽

Bound Water ◽

Hydrophobic Hydration ◽

Water Network ◽

Molecular Scaffold ◽

Intermediate Activity ◽

Mold Fungus ◽

Antifreeze Activity

AbstractAntifreeze proteins (AFPs) inhibit ice growth by adsorbing onto specific ice planes. Microbial AFPs show diverse antifreeze activity and ice plane specificity, while sharing a common molecular scaffold. To probe the molecular mechanisms responsible for AFP activity, we here characterized the antifreeze activity and crystal structure of TisAFP7 from the snow mold fungus Typhula ishikariensis. TisAFP7 exhibited intermediate activity, with the ability to bind the basal plane, compared with a hyperactive isoform TisAFP8 and a moderately active isoform TisAFP6. Analysis of the TisAFP7 crystal structure revealed a bound-water network arranged in a zigzag pattern on the surface of the protein’s ice-binding site (IBS). While the three AFP isoforms shared the water network pattern, the network on TisAFP7 IBS was not extensive, which was likely related to its intermediate activity. Analysis of the TisAFP7 crystal structure also revealed the presence of additional water molecules that form a ring-like network surrounding the hydrophobic side chain of a crucial IBS phenylalanine, which might be responsible for the increased adsorption of AFP molecule onto the basal plane. Based on these observations, we propose that the extended water network and hydrophobic hydration at IBS together determine the TisAFP activity.

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Synchrotron X-Ray Topography Study on the Relationship between Local Basal Plane Bending and Basal Plane Dislocations in PVT-Grown 4H-SiC Substrate Wafers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1004.393 ◽

2020 ◽

Vol 1004 ◽

pp. 393-400

Author(s):

Tuerxun Ailihumaer ◽

Hongyu Peng ◽

Balaji Raghothamachar ◽

Michael Dudley ◽

Gilyong Chung ◽

...

Keyword(s):

Basal Plane ◽

Local Strain ◽

Grazing Incidence ◽

Peak Shift ◽

Linear Mapping ◽

Incidence Geometry ◽

Convex Shape ◽

X Ray ◽

Black And White ◽

Plane Bending

Synchrotron monochromatic beam X-ray topography (SMBXT) in grazing incidence geometry shows black and white contrast for basal plane dislocations (BPDs) with Burgers vectors of opposite signs as demonstrated using ray tracing simulations. The inhomogeneous distribution of these dislocations is associated with the concave/convex shape of the basal plane. Therefore, the distribution of these two BPD types were examined for several 6-inch diameter 4H-SiC substrates and the net BPD density distribution was used for evaluating the nature and magnitude of basal plane bending in these wafers. Results show different bending behaviors along the two radial directions - [110] and [100] directions, indicating the existence of non-isotropic bending. Linear mapping of the peak shift of the 0008 reflection along the two directions was carried out using HRXRD to correlate with the results from the SMBXT measurements. Basal-plane-tilt angle calculated using the net BPD density derived from SMBXT shows a good correlation with those obtained from HRXRD measurements, which further confirmed that bending in basal plane is caused by the non-uniform distribution of BPDs. Regions of severe bending were found to be associated with both large tilt angles (95% black contrast BPDs to 5% white contrast BPDs) and abrupt changes in a and c lattice parameters i.e. local strain.

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