Spinel as Exit Aperture Window for HEL Systems

2008 ◽  
Author(s):  
Ishwar Aggarwal ◽  
Shyam Bayya ◽  
Guillermo Villaiobos ◽  
Woohong Kim ◽  
Jasbinder Sanghera ◽  
...  
Keyword(s):  
Exit Aperture

Protein Crystallography Using Capillary-Focused X-Rays

1996 ◽  
Vol 54 ◽  
pp. 238-239
Author(s):  
D. X. Balaic ◽  
Z. Barnea ◽  
K. A. Nugent ◽  
R. F. Garrett ◽  
J. N. Varghese ◽  
...  
Keyword(s):  
Fluorescence Analysis ◽  
Focal Region ◽  
X Rays ◽  
Glass Capillary ◽  
Synchrotron Source ◽  
X Ray ◽  
Exit Aperture ◽  
Egg White Lysozyme ◽  
Diffraction Patterns ◽  
Focused Beam

Tapered glass capillaries for X-ray beam concentration have been a topic of much interest for the synchrotron X-ray community in recent years. These optics have long held the promise of high-intensity microbeam generation for the “hard” X-ray energies used in crystallography and fluorescence analysis.X-ray concentration is achieved by exploiting the total external reflection property of glass surfaces for glancing angles of incidence. X-rays directed into the entrance aperture of the capillary are reflected toward an exit aperture of smaller dimensions, resulting in an increased X-ray flux per unit area at the exit aperture. Capillary designs with a true geometrical focus beyond the capillary exit are also possible.Our group has recently demonstrated a paraboloidally-tapered glass capillary optic which produced a focused X-ray beam using a monochromatised synchrotron source. The optic was designed to produce a focal region for singly-reflected X-rays at a point 40 mm from the end of the capillary. Such a focal region was observed, with a FWHM intensity gain of two orders of magnitude over the incident X-ray intensity from the channel-cut monochromator. Moreover, this gain was achieved for X-ray energies from 5 to 20 keV. We subsequently used a similar optic to obtain X-ray diffraction patterns from a crystal of hen egg-white lysozyme on image plates. The use of the capillary-focused beam yielded diffraction patterns 70 to 100 times faster than using an unfocused beam from the channel-cut monochromator alone. Placement of the crystal at different positions in the capillary-focused beam demonstrated the focusing of Bragg reflections and diffraction from a small volume of crystal.

A source of a reference spherical wave based on a single mode optical fiber with a narrowed exit aperture

2008 ◽  
Vol 79 (3) ◽  
pp. 033107 ◽  
Author(s):  
N. I. Chkhalo ◽  
A. Yu. Klimov ◽  
V. V. Rogov ◽  
N. N. Salashchenko ◽  
M. N. Toropov
Keyword(s):  
Optical Fiber ◽  
Spherical Wave ◽  
Single Mode ◽  
Single Mode Optical Fiber ◽  
Exit Aperture

Uniformity Research of Integrating Spheres Reference Light Source with Large Exit Aperture

2015 ◽  
Vol 44 (4) ◽  
pp. 422003
Author(s):  
袁银麟 YUAN Yin-lin ◽  
郑小兵 ZHENG Xiao-bing ◽  
吴浩宇 WU Hao-yu ◽  
张黎明 ZHANG Li-ming
Keyword(s):  
Light Source ◽  
Exit Aperture

scholarly journals Symmetric Compound Parabolic Concentrator with Indium Tin Oxide Coated Glass as Passive Cooling System for Photovoltaic Application

2016 ◽  
Vol 2016 ◽  
pp. 1-12
Author(s):  
Damasen Ikwaba Paul
Keyword(s):  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Visible Region ◽  
Solar Spectrum ◽  
Infrared Region ◽  
Passive Cooling ◽  
Photovoltaic Module ◽  
Coated Glass ◽  
Compound Parabolic Concentrator ◽  
Exit Aperture

One problem with concentrating photovoltaic systems is the increase in operating photovoltaic module temperature which results in power output reduction. Indium Tin Oxide (ITO) coated glasses exhibit both high transmittance in the visible region and high reflectance in the infrared region of the solar spectrum. Such materials can be used as selective windows in photovoltaic modules operating under concentrating system enabling passive cooling. In this paper, a Heat Reflector Window (HRW) consisting of a glass coated with 180 nm layer of ITO was experimentally tested. The ITO coated glass had a transmittance of about 85% in the visible region and over 80% reflectance in the infrared region of the solar spectrum and was placed at the exit aperture of a Compound Parabolic Concentrator (CPC). Results indicate that the temperature of a photovoltaic module under CPC with the HRW was reduced by about 50% as compared to a similar photovoltaic module with CPC but without the HRW. However, due to presence of the HRW at the exit aperture of the CPC, the photovoltaic module with the CPC and HRW received less solar irradiance compared to a similar photovoltaic module with the CPC but without HRW.

Study the optimum dimensions and operating parameters of Penning ion source

2017 ◽  
Vol 95 (5) ◽  
pp. 457-463 ◽  
Author(s):  
A.G. Helal ◽  
H. El-Khabeary ◽  
S.I. Radwan
Keyword(s):  
Discharge Current ◽  
Ion Beam ◽  
Surface Hardness ◽  
Beam Current ◽  
Discharge Voltage ◽  
Ion Source ◽  
Aperture Diameter ◽  
Argon Gas ◽  
Exit Aperture ◽  
Hollow Anode

In this work, design and construction of a DC cold cathode Penning ion source is described. It consists of cylindrical hollow anode and two movable disc cathodes that are placed symmetrically at two ends of the anode. The electrical discharge and the output ion beam characteristics of the ion source are measured using argon gas. It is found that the optimum dimensions of anode–cathode distance, ion exit aperture diameter, and ion exit aperture – Faraday cup distance are equal to 8, 1.5, and 30 mm, respectively. The ion source efficiency was calculated at discharge current equal to 1.2 mA, different anode–cathode distances and pressures using argon gas. It is found that at anode–cathode distance equal to 8 mm and pressure equal to 7 × 10−4 mmHg, a maximum ion source efficiency equal to 27.1% can be obtained. The surface hardness of molybdenum specimen is measured after exposure to argon ion beam for two hours at pressure equal to 7 × 10−4 mmHg, discharge voltage equal to 3.5 kV, discharge current equal to 0.6 mA, and output ion beam current equal to 165 μA using argon gas. It is found that the surface hardness of molybdenum specimen is decreased by a factor of 24.2%.

Sign in / Sign up

Export Citation Format

Share Document