Dissociative adsorption of H2O and CO2 on the clean and O-pre-covered high index Ru surfaces: Corrugated Ru(11−21) and stepped Ru(20−21) surfaces

A technique that made it possible for the first time to achieve fivefold symmetry in palladium nanocrystallites grown on the surface of a Pd-Cu film has been developed. Pd-40%Cu membrane modification with pentatwinned nanocrystallites with high-index facets made it possible to achieve ultra-high hydrogen permeability up to 10.1 mmol s-1 m-2 at 100 °C. Such permeability, comparable in value to high-temperature analogs, is anomalous, since the predicted values should be more than 2 times lower than those obtained. This result is due to the acceleration of surface dissociative adsorption and recombinative desorption as a result of the pentatwinned particles ultra-high activity in reactions involving hydrogen, which is confirmed by the data on the selectivity of the developed membranes.

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The usefulness of high index low symmetry zone axes for holz line analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126718 ◽

1987 ◽

Vol 45 ◽

pp. 384-385

Author(s):

C. M. Sung ◽

D. B. Williams

Keyword(s):

Lattice Parameter ◽

High Order ◽

Zone Axis ◽

High Index ◽

High Symmetry ◽

Second Phases ◽

Line Patterns ◽

Low Symmetry ◽

Line Analysis

Researchers have tended to use high symmetry zone axes (e.g. <111> <114>) for High Order Laue Zone (HOLZ) line analysis since Jones et al reported the origin of HOLZ lines and described some of their applications. But it is not always easy to find HOLZ lines from a specific high symmetry zone axis during microscope operation, especially from second phases on a scale of tens of nanometers. Therefore it would be very convenient if we can use HOLZ lines from low symmetry zone axes and simulate these patterns in order to measure lattice parameter changes through HOLZ line shifts. HOLZ patterns of high index low symmetry zone axes are shown in Fig. 1, which were obtained from pure Al at -186°C using a double tilt cooling holder. Their corresponding simulated HOLZ line patterns are shown along with ten other low symmetry orientations in Fig. 2. The simulations were based upon kinematical diffraction conditions.

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Reduction in Depth for a Radiating Flange Backed by a Rectangular Resonant Cavity Using High Index Materials: Preliminary Report

10.21236/ada590611 ◽

2013 ◽

Author(s):

Gregory A. Mitchell

Keyword(s):

Preliminary Report ◽

Resonant Cavity ◽

High Index

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Challenges and Issues in the Design of Micro-Machined Antennas - A Review

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096513999200922124417 ◽

2020 ◽

Vol 13 ◽

Author(s):

Ashish Kumar ◽

Amar Partap Singh Pharwaha

Keyword(s):

Patch Antenna ◽

Ground Plane ◽

Substrate Material ◽

Review Article ◽

High Index ◽

Performance Characteristics ◽

Machining Process ◽

Patch Antennas ◽

Micro Machining ◽

The Impact

Background: Patch antennas are composed of the substrate material with patch and ground plane on the both sides of the substrate. The dimensions and performance characteristics of the antenna are highly influenced by the choice of the appropriate substrate depending upon the value of their dielectric constant. Generally, low index substrate materials are used to design the patch antenna but there are also some of the applications, which require the implementation of patch antenna design on high index substrate like silicon and gallium arsenide. Objective: The objective of this article is to review the design of antennas developed on high index substrate and the problems associated with the use of these materials as substrate. Also, main challenges and solutions have been discussed to improve the performance characteristics while using the high index substrates. Method: The review article has divided into various sections including the solution of the problems associated with the high index substrates in the form of micro-machining process. Along with this, types of micro machining and their applications have discussed in detail. Results: This review article investigates the various patch antennas designed with micro-machining technology and also discusses the impact of micro-machining process on the performance parameters of the patch antennas designed on high index substrates. Conclusion: By using the micro-machining process, the performance of patch antenna improves drastically but fabrication and tolerances at such minute structures is very tedious task for the antenna designers.

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Neurobrucellosis associated with feral swine hunting in the southern United States

BMJ Case Reports ◽

10.1136/bcr-2020-238216 ◽

2020 ◽

Vol 13 (12) ◽

pp. e238216

Author(s):

Harry Ross Powers ◽

Jared R Nelson ◽

Salvador Alvarez ◽

Julio C Mendez

Keyword(s):

United States ◽

At Risk ◽

High Index ◽

Southern United States ◽

Endemic Country ◽

Feral Swine ◽

Neurological Sequelae ◽

Initial Symptoms ◽

The Usa ◽

High Index Of Suspicion

Although uncommon, Brucella infection can occur outside the areas of high endemicity, such as the USA. In the southern USA, hunters of wild swine are at risk for brucellosis. We present a case of a patient with fever, headache and constitutional symptoms that were ongoing for 11 months. He was diagnosed with neurobrucellosis. The patient was treated successfully with intravenous ceftriaxone, oral doxycycline and oral rifampin therapy. He had persistent neurological sequelae after completing treatment. This case illustrates the high index of suspicion needed to diagnose neurobrucellosis in a non-endemic country because initial symptoms can be subtle. The disease can be treated successfully, but long-lasting neurological sequelae are common.

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