Design of dual-function metasurface based on beam polarization characteristics

2021 ◽  
Vol 117 ◽  
pp. 111199
Author(s):  
Honggang Hao ◽  
Sen Zheng ◽  
Yihao Tang ◽  
Xuehong Ran
Keyword(s):  
Beam Polarization ◽  
Dual Function ◽  
Polarization Characteristics

scholarly journals Investigation of the polarization state of dual APPLE-II undulators

2016 ◽  
Vol 23 (1) ◽  
pp. 176-181 ◽  
Author(s):  
Matthew Hand ◽  
Hongchang Wang ◽  
Sarnjeet S. Dhesi ◽  
Kawal Sawhney
Keyword(s):  
Polarization State ◽  
Polarized Light ◽  
Photon Flux ◽  
Beam Polarization ◽  
Polarization Angle ◽  
Circularly Polarized Light ◽  
X Ray ◽  
Processing Procedure ◽  
Polarization Characteristics ◽  
Data Acquisition And Processing

The use of an APPLE II undulator is extremely important for providing a high-brilliance X-ray beam with the capability to switch between various photon beam polarization states. A high-precision soft X-ray polarimeter has been used to systematically investigate the polarization characteristics of the two helical APPLE II undulators installed on beamline I06 at Diamond Light Source. A simple data acquisition and processing procedure has been developed to determine the Stokes polarization parameters for light polarized at arbitrary linear angles emitted from a single undulator, and for circularly polarized light emitted from both undulators in conjunction with a single-period undulator phasing unit. The purity of linear polarization is found to deteriorate as the polarization angle moves away from the horizontal and vertical modes. Importantly, a negative correlation between the degree of circular polarization and the photon flux has been found when the phasing unit is used.

scholarly journals Patches of Dual Functions for Wideband MIMO Array Antenna with Linear or Circular Polarization Characteristics

2021 ◽  
Author(s):  
Reza Zaker ◽  
Mohsen Khalily ◽  
Rahim Tafazolli ◽  
Ahmed A. Kishk
Keyword(s):  
Ground Plane ◽  
Array Antenna ◽  
Ultra Wideband ◽  
Dual Function ◽  
Peak Efficiency ◽  
Linearly Polarized ◽  
Polarization Characteristics ◽  
Broadside Radiation ◽  
First Time ◽  
Better Than

Abstract In this paper, a design of a monopole-based four-element MIMO array antenna is proposed. The design is based on a novel technique that makes a patch be a ground plane of the next patch. Thus, each patch has a dual function. This method is named the sharing technique. Thus, for the first time, two of such antennas can be merged, providing a subminiature structure. The method is introduced step by step. Then, a 2×2 MIMO array with a total area of 49×49 mm 2 is designed, which provides a miniaturized of 57% (from 0.18λ 2 0 to 0.076λ 2 0 @ 1.7GHz). Two linearly-polarized array samples are evaluated. One sample with center-fed patches and another with off-center-fed. Both samples provide a semi-end-fire pattern with a minimum front-to-back (F/B) ratio of 11dB and 360° rotation capability with wide 10-dB S 11 bandwidths over 100%. Moreover, an ultra-wideband circularly polarized array with broadside radiation can be achieved by simultaneous, sequential exciting all ports. The antenna achieves isolation better than 15dB, peak efficiency of 95%, and 5.9dBi gain verified with different measurements.

THE BALANCE OF PROBABILITY: STATISTICS AND THE DIACHRONIC STUDY OF ANCIENT HEBREW

2017 ◽  
Vol 25 (2) ◽  
pp. 927-960
Author(s):  
Jarod Jacobs
Keyword(s):  
Dead Sea Scrolls ◽  
Dead Sea ◽  
Biblical Hebrew ◽  
Large Datasets ◽  
Dual Function ◽  
Statistical Tools ◽  
Masoretic Text ◽  
Linguistic Research ◽  
Recent Debate ◽  
Diachronic Study

In this article, I discuss three statistical tools that have proven pivotal in linguistic research, particularly those studies that seek to evaluate large datasets. These tools are the Gaussian Curve, significance tests, and hierarchical clustering. I present a brief description of these tools and their general uses. Then, I apply them to an analysis of the variations between the “biblical” DSS and our other witnesses, focusing upon variations involving particles. Finally, I engage the recent debate surrounding the diachronic study of Biblical Hebrew. This article serves a dual function. First, it presents statistical tools that are useful for many linguistic studies. Second, it develops an analysis of the he-locale, as it is used in the “biblical” Dead Sea Scrolls, Masoretic Text, and Samaritan Pentateuch. Through that analysis, this article highlights the value of inferential statistical tools as we attempt to better understand the Hebrew of our ancient witnesses.

Dual-Function, Light Switchable Cobalt Catalysis via Active Site Metamorphosis

2019 ◽  
Author(s):  
Enrico Bergamaschi ◽  
Frédéric Beltran ◽  
Christopher Teskey
Keyword(s):  
Visible Light ◽  
Active Site ◽  
Catalytic Site ◽  
Dual Function ◽  
Catalytic Systems ◽  
Hydride Complex ◽  
Dual Functional ◽  
Multiple Processes ◽  
Olefin Migration

<p></p><p></p><p>Switchable catalysis offers opportunities to control the rate or selectivity of a reaction <i>via</i> a stimulus such as pH or light. However, few examples of switchable catalytic systems that can facilitate multiple processes exist. Here we report a rare example of such dual-functional, switchable catalysis. Featuring an easily prepared, bench-stable cobalt(I) hydride complex in conjunction with pinacolborane, we can completely alter the reaction outcome between two widely employed transformations – olefin migration and hydroboration – with visible light as the sole trigger. This dichotomy arises from ligand photodissociation which leads to metamorphosis of the active catalytic site, resulting in divergent mechanistic pathways.</p><p></p><p></p>

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