Variable-deceleration-ratio wide-acceptance-angle electrostatic lens for two-dimensional angular and energy analysis

2018 ◽  
Vol 89 (12) ◽  
pp. 123105 ◽  
Author(s):  
Hiroyuki Matsuda ◽  
László Tóth ◽  
Hiroshi Daimon
Keyword(s):  
Energy Analysis ◽  
Two Dimensional ◽  
Acceptance Angle ◽  
Electrostatic Lens ◽  
Wide Acceptance

A New Troughlike Nonimaging Solar Concentrator

2001 ◽  
Vol 124 (1) ◽  
pp. 51-54 ◽  
Author(s):  
Eduardo A. Rinco´n ◽  
Fidel A. Osorio
Keyword(s):  
Concentration Ratio ◽  
Glass Tube ◽  
Two Dimensional ◽  
Solar Concentrator ◽  
Steam Generation ◽  
Acceptance Angle ◽  
Practical Applications ◽  
Optimal Shapes ◽  
Heating Steam ◽  
East West

A new two-dimensional concentrator for solar energy collection has been developed. The concentrator has the following advantages, when compared with the classic Compound Parabolic Concentrators invented by Roland Winston, W. T. Welford, A. Rabl, Baranov, and other researchers: 1) It allows the use of parabolic mirrors, which have a reflecting area much smaller for a given concentration ratio and acceptance angle. 2) Between the mirror and the absorber, there is a large gap so that conduction losses are reduced. Convection losses can be reduced, too, if the absorber is enclosed within a glass tube. 3) It can be easily manufactured. Instead of seeking the shape of the mirrors for a given shape of the absorber, we have made the inverse statement of the problem, and we have obtained the optimal shapes of the absorbers with a prescribed acceptance angle, for parabolic mirrors, assuming that the intercept factor is unity, the mirrors are perfect, and the absorber surfaces are convex. The concentrator should be east-west oriented, and could be seasonal or monthly tilt adjusted. This concentrator could have many practical applications, such as fluid heating, steam generation, etc.

Origami-Based Bistable Metastructures for Low-Frequency Vibration Control

2021 ◽  
Vol 88 (5) ◽  
Author(s):  
Mingkai Zhang ◽  
Jinkyu Yang ◽  
Rui Zhu
Keyword(s):  
Vibration Isolation ◽  
Energy Analysis ◽  
Geometrical Nonlinearity ◽  
Low Frequency ◽  
Quantitative Relationship ◽  
Vibration Modes ◽  
Two Dimensional ◽  
Low Frequency Vibration ◽  
Dynamic Experiments ◽  
Unit Cells

Abstract In this research, we aim to combine origami units with vibration-filtering metastructures. By employing the bistable origami structure as resonant unit cells, we propose metastructures with low-frequency vibration isolation ability. The geometrical nonlinearity of the origami building block is harnessed for the adjustable stiffness of the metastructure’s resonant unit. The quantitative relationship between the overall stiffness and geometric parameter of the origami unit is revealed through the potential energy analysis. Both static and dynamic experiments are conducted on the bistable origami cell and the constructed beam-like metastructure to verify the adjustable stiffness and the tunable vibration isolation zone, respectively. Finally, a two-dimensional (2D) plate-like metastructure is designed and numerically studied for the control of different vibration modes. The proposed origami-based metastructures can be potentially useful in various engineering applications where structures with vibration isolation abilities are appreciated.

Spherical micro-hole grid for high-resolution retarding field analyzer

2021 ◽  
Vol 28 (5) ◽  
Author(s):  
Takayuki Muro ◽  
Tomohiro Matsushita ◽  
Kazumi Sawamura ◽  
Jun Mizuno
Keyword(s):  
High Resolution ◽  
Energy Resolution ◽  
Cylindrical Hole ◽  
Display Type ◽  
Photoemission Spectrum ◽  
Acceptance Angle ◽  
Wide Acceptance ◽  
Inner Radius ◽  
Micro Hole ◽  
Cylindrical Holes

A wide-acceptance-angle spherical grid composed of numerous micro cylindrical holes was developed to be used for the retarding grid of a display-type retarding field analyzer (RFA) and to enhance the energy resolution (E/ΔE). Each cylindrical hole with a diameter of 50 µm and a depth of 80 µm is directed to the spherical center. The inner radius of the spherical grid is 40 mm. The holed area corresponds to an acceptance angle of ±52°. The E/ΔE of an RFA equipped with the developed holed grid was estimated to be 2000 from a measured Au 4f photoemission spectrum. A clear photoelectron hologram was observed in the Mo 4p core-level region of MoS2, indicating that the RFA with the holed grid is effective for photoelectron holography.

Diffraction Space Mapping of Heteroepitaxial Layers

1994 ◽  
Vol 38 ◽  
pp. 151-164
Author(s):  
Mary Halliwell
Keyword(s):  
Lattice Parameter ◽  
Space Mapping ◽  
Two Dimensional ◽  
Acceptance Angle ◽  
Rocking Curve ◽  
Cell Dimensions ◽  
Parameter Variations ◽  
Unit Cell Dimensions ◽  
Heteroepitaxial Layers ◽  
Defect Densities

Abstract The acceptance angle of the detector of a double axis diffractometer is designed such that all of the diffracted beam is recorded for a rocking curve. When this acceptance angle is reduced, as in the triple axis diffractometer, two dimensional diffraction data can be recorded. In the resulting diffraction space maps each diffraction feature has a shape and a position from which the unit cell dimensions of a heteroepitaxial layer can be derived as well as information about relative tilts, curvature, lattice parameter variations and defect densities. Applications of diffraction space mapping using high and low resolution optics are discussed

Electron focusing in two‐dimensional systems by means of an electrostatic lens

1990 ◽  
Vol 56 (13) ◽  
pp. 1290-1292 ◽  
Author(s):  
J. Spector ◽  
H. L. Stormer ◽  
K. W. Baldwin ◽  
L. N. Pfeiffer ◽  
K. W. West
Keyword(s):  
Two Dimensional ◽  
Electrostatic Lens ◽  
Electron Focusing
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