Effect of the microchannel plate design on the capacity of methanol steam reformers

2007 ◽  
Vol 48 (5) ◽  
pp. 765-771 ◽  
Author(s):  
L. L. Makarshin ◽  
D. V. Andreev ◽  
A. G. Gribovskii ◽  
P. M. Dutov ◽  
R. M. Khantakov ◽  
...  
Author(s):  
James F. Mancuso ◽  
Leo A. Fama ◽  
William B. Maxwell ◽  
Jerry L. Lehman ◽  
Hasso Weiland ◽  
...  

Micro-diffraction based crystallography is essential to the design and development of many classes of ‘crafted materials’. Although the scanning electron microscope can provide crystallographic information with high spatial resolution, its current utility is severely limited by the low sensitivity of existing diffraction techniques (ref: Dingley). Previously, Joy showed that energy filtering increased contrast and pattern visibility in electron channelling. This present paper discribes the effect of energy filtering on EBSP sensitivity and backscattered SEM imaging.The EBSP detector consisted of an electron energy filter, a microchannel plate detector, a phosphor screen, optical coupler, and a slow scan CCD camera. The electrostatic energy filter used in this experiment was constructed as a cone with 5 coaxial electrodes. The angular field-of-view of the filter was approximately 38°. The microchannel plate, which was the initial sensing component, had high gain and had 50% to 80% detection efficiency for the low energy electrons that passed through the retarding field filter.


Author(s):  
Galen Powers ◽  
Ray Cochran

The capability to obtain symmetrical images at voltages as low as 200 eV and beam currents less than 9 pico amps is believed to be advantageous for metrology and study of dielectric or biological samples. Symmetrical images should allow more precise and accurate line width measurements than currently achievable by traditional secondary electron detectors. The low voltage and current capability should allow imaging of samples which traditionally have been difficult because of charging or electron beam damage.The detector system consists of a lens mounted dual anode MicroChannel Plate (MCP) detector, vacuum interface, power supplies, and signal conditioning to interface directly to the video card of the SEM. The detector has been miniaturized so that it does not interfere with normal operation of the SEM sample handling and alternate detector operation. Biasing of the detector collection face will either add secondaries to the backscatter signal or reject secondaries yielding only a backscatter image. The dual anode design allows A−B signal processing to provide topological information as well as symmetrical A+B images.Photomicrographs will show some of the system capabilities. Resolution will be documented with gold on carbon. Variation of voltage, beam current, and working distance on dielectric samples such as glass and photoresist will demonstrate effects of common parameter changes.


2010 ◽  
Vol 41 (3) ◽  
pp. 233-245 ◽  
Author(s):  
C. Ventura ◽  
J. L. T. Azevedo

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Weiwei Cao ◽  
Bingli Zhu ◽  
Xiaohong Bai ◽  
Peng Xu ◽  
Bo Wang ◽  
...  

Eye ◽  
2021 ◽  
Author(s):  
Inês C. F. Pereira ◽  
Rosanne van de Wijdeven ◽  
Hans M. Wyss ◽  
Henny J. M. Beckers ◽  
Jaap M. J. den Toonder

AbstractGlaucoma is a progressive optic neuropathy that is the second leading cause of preventable blindness worldwide, after cataract formation. A rise in the intraocular pressure (IOP) is considered to be a major risk factor for glaucoma and is associated with an abnormal increase of resistance to aqueous humour outflow from the anterior chamber. Glaucoma drainage devices have been developed to provide an alternative pathway through which aqueous humour can effectively exit the anterior chamber, thereby reducing IOP. These devices include the traditional aqueous shunts with tube-plate design, as well as more recent implants, such as the trabeculectomy-modifying EX-PRESS® implant and the new minimally invasive glaucoma surgery (MIGS) devices. In this review, we will describe each implant in detail, focusing on their efficacy in reducing IOP and safety profile. Additionally, a critical and evidence-based comparison between these implants will be provided. Finally, we will propose potential developments that may help to improve the performance of current devices.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Yuman Wang ◽  
Shulin Liu ◽  
Baojun Yan ◽  
Ming Qi ◽  
Kaile Wen ◽  
...  

An amendment to this paper has been published and can be accessed via the original article.


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