CHARACTERISTICS AND FUNCTION OF AN ELECTRON ATTACHMENT SPECTROMETER: PULSE FORMATION TIME AND GAIN EFFECTS IN P-10 GAS

An Electron Attachment Spectrometer (EAS) has been designed to measure electron attachment in air and other gases. The aim of the EAS is to observe how parameters such as the electric field, reduced electric field and type of gas can influence electron attachment. The overall objective of this work is to investigate if the gas-gain of a proportional counter can be optimized by minimizing electron attachment with oxygen to improve the measurement of tritium-in-air. Current research interests include the measurement of the time between the generation of the electron–ion pairs and arrival of the electrons at the wire anode. Additionally, the study of the multiplication properties of the detector as a function of pulse formation time, P-10 gas flow rate and electric field will be presented. The EAS is a cylinder with a length of approximately 92 mm and diameter of 41 mm comprised of cylindrical hollow brass electrodes and Teflon spacers. A uniform electric field within the tube is applied and guides electrons and/or ions towards their respective electrodes. A proportional counter with a 50 μm diameter wire anode is used to detect the electrons and/or ions created by an 241 Am source located at the opposite end.

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Optimization of Light Emission from Silicon Nanocrystals Grown by PECVD

MRS Proceedings ◽

10.1557/proc-1257-o03-05 ◽

2010 ◽

Vol 1257 ◽

Author(s):

Satoshi Ishikawa ◽

Szu-Lin Cheng ◽

Yiyang Gong ◽

Jelena Vuckovic ◽

Yoshio Nishi

Keyword(s):

Electric Field ◽

Flow Rate ◽

Gas Flow ◽

Annealing Temperature ◽

Light Emission ◽

Layer Structure ◽

Forward Bias ◽

Vertical Direction ◽

Carrier Injection ◽

Gas Flow Rate

AbstractLight emission from Si nanocrystals ( SiNCs ) embedded in Si oxide was studied in this work. SiNCs were fabricated by annealing a Si-rich oxide ( SRO ) deposited by a plasma-enhanced chemical vapor deposition ( PECVD ) system. The gas flow ratio between SiH4 and N2O of a precursor gas was changed by varying a N2O gas flow rate and the annealing temperature was varied from 800 to 1100°C. The highest PL intensity was obtained with a N2O flow rate of 125sccm, a SiH4 flow rate of 1400sccm and annealing temperature of 900°C. The PL wavelength was also controlled by N2O gas flow rate and annealing temperature, with blue shifting to the visible wavelengths for increasing N2O flow rate and decreasing annealing temperature. In addition, forming gas ( 4% H2 ) anneal for 1 hour, which is a common method to passivate Si surface, at 500°C to SiNCs was used to further enhance the emission intensity. To approach emission at shorter wavelength, the Si oxide with SiNCs / SiO2 multi layer structure ( MLS ) was also fabricated by similar methods. The SiO2 layer was used as a diffusion barrier to extra Si on vertical direction during the annealing process. Such a barrier can effectively reduce the diameter of SiNCs and shift the emission peak to shorter wavelength. A blue shift from PL was clearly observed as the thickness of Si oxide layer with SiNCs in MLS reduces. Finally, the PIN light emitting diode which consisted of n-type poly-Si / Si oxide with SiNCs / p-type poly-Si structure was also fabricated to study the electroluminescence ( EL ) of SiNCs. The current under the forward bias was about 10 times higher than under the reverse bias. The carrier injection mechanism assumed that Poole-Frenkel type conduction or hopping conduction dominates under a low electric field and Fowler-Nordheim tunneling dominates under a high electric field. EL was obtained with a forward bias voltage of around 6V and EL emission efficiency was proportional to the current density.

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Simulation and Experimental Research on the Charged Characteristics of Particulate Matter in the Sensor under Different Exhaust States

Sensors ◽

10.3390/s20216226 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6226

Author(s):

Dong Tang ◽

Zhixuan Ju ◽

Li Wang

Keyword(s):

Particulate Matter ◽

Electric Field ◽

Flow Rate ◽

Electric Charge ◽

Gas Flow ◽

Particulate Filter ◽

Uniform Electric Field ◽

Exhaust Gas ◽

Growth Trend ◽

Tracking Model

The particulate matter sensor needs to be used in order to detect the concentration of particulate matter in diesel engine exhaust, monitor the working condition of diesel particulate filter (DPF) in real time, and ensure the reliable operation of DPF. The flow field and electric field of the sensor are studied and their distribution in the sensor is analyzed. At the same time, the particle tracking model was used to simulate the charged characteristics of particles in the sensor under different exhaust states. It is found that the exhaust gas flow rate maintains stability after entering the outer protection zone and concentration test zone. The electric field is a non-uniform electric field and the direction of electric field intensity is from the high voltage electrode to the grounding electrode. The electric charge per particle will decrease with the increase of exhaust flow rate, but the electric charge shows a slow growth trend. The charge of particles increases with the increase of exhaust temperature, exhaust gas concentration and particle size. The study of the charged characteristics under different environmental conditions provides a theoretical basis for further improving the prototype mechanism of a leakage flow particle sensor.

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Multi-Stage Collector Design and Applications

2003 International Joint Power Generation Conference ◽

10.1115/ijpgc2003-40021 ◽

2003 ◽

Author(s):

Henry V. Krigmont

Keyword(s):

Electric Field ◽

Corona Discharge ◽

Gas Flow ◽

Uniform Electric Field ◽

Two Stage ◽

Current State ◽

Fine Particulate ◽

Multi Stage ◽

Corrugated Plates ◽

Particulate Control

The Multi Stage Collector (MSC™) concept for ultra-fine particulate control not only retains the best advantages of current state-of-the-art technology but also makes significant improvements. The new MSC™ design provides a synergistic combination of both single- and two-stage electrostatic precipitation while incorporating an additional collector-stage by filtering the gas exiting the collector through a barrier collector-zone. This arrangement ensures that essentially all dust would be detained in this final stage. The MSC™ contains multiple narrow and wide zones formed by a plurality of parallel corrugated plates. Enclosed in the narrow zones are discharge electrodes. These electrodes provide a non-uniform electric field leading to corona discharge. The corona discharge causes particulate matter in the gas flow to become charged. Wide regions contain barrier filters thus creating the two-stage precipitator with relatively uniform electric field. In these regions, particles are collected on both plates and on the porous barrier elements, which also act as the final filtering stage. Results of the applications analyses and future development work are discussed. The gas flow analyses with an aid of the CFD model are presented below.

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Studies on Characteristics of Electron Capture Responses. V. Estimation of Electron Attachment Mechanisms from Carrier Gas Flow-rate Dependence of Electron Capture Coefficients

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.54.2466 ◽

1981 ◽

Vol 54 (8) ◽

pp. 2466-2469 ◽

Cited By ~ 1

Author(s):

Masahiro Takeuchi

Keyword(s):

Electron Capture ◽

Flow Rate ◽

Gas Flow ◽

Electron Attachment ◽

Rate Dependence ◽

Gas Flow Rate ◽

Carrier Gas ◽

Carrier Gas Flow

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Proportional counter with a uniform electric field in the zone of avalanche multiplication of electrons

Nuclear Instruments and Methods in Physics Research ◽

10.1016/0167-5087(82)90454-9 ◽

1982 ◽

Vol 200 (2-3) ◽

pp. 355-359 ◽

Cited By ~ 5

Author(s):

J. Marzec ◽

Z. Pawlowski

Keyword(s):

Electric Field ◽

Proportional Counter ◽

Uniform Electric Field ◽

Avalanche Multiplication

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SCIENTIFIC AND ENGINEERING PRINCIPLES OF EFFICIENT FUEL USE AND ENVIRONMENTALLY FRIENDLY GAS COMBUSTION IN STOVE PLATES. PART 1. MODERN STATE-OF-THE-ART AND DIRECTIONS FOR IMPROVEMENT THE GAS BURNING IN DOMESTIC GAS COOKERS

Energy Technologies & Resource Saving ◽

10.33070/etars.3.2017.01 ◽

2017 ◽

pp. 3-18 ◽

Cited By ~ 1

Author(s):

B.S. Soroka ◽

V.V. Horupa

Keyword(s):

Natural Gas ◽

Flow Rate ◽

Gas Flow ◽

Renewable Energy Sources ◽

Combustion Process ◽

Orifice Diameter ◽

Firing Process ◽

Gas Flow Rate ◽

Gas Combustion ◽

Gas Stoves

Natural gas NG consumption in industry and energy of Ukraine, in recent years falls down as a result of the crisis in the country’s economy, to a certain extent due to the introduction of renewable energy sources along with alternative technologies, while in the utility sector the consumption of fuel gas flow rate enhancing because of an increase the number of consumers. The natural gas is mostly using by domestic purpose for heating of premises and for cooking. These items of the gas utilization in Ukraine are already exceeding the NG consumption in industry. Cooking is proceeding directly in the living quarters, those usually do not meet the requirements of the Ukrainian norms DBN for the ventilation procedures. NG use in household gas stoves is of great importance from the standpoint of controlling the emissions of harmful components of combustion products along with maintenance the satisfactory energy efficiency characteristics of NG using. The main environment pollutants when burning the natural gas in gas stoves are including the nitrogen oxides NOx (to a greater extent — highly toxic NO2 component), carbon oxide CO, formaldehyde CH2O as well as hydrocarbons (unburned UHC and polyaromatic PAH). An overview of environmental documents to control CO and NOx emissions in comparison with the proper norms by USA, EU, Russian Federation, Australia and China, has been completed. The modern designs of the burners for gas stoves are considered along with defining the main characteristics: heat power, the natural gas flow rate, diameter of gas orifice, diameter and spacing the firing openings and other parameters. The modern physical and chemical principles of gas combustion by means of atmospheric ejection burners of gas cookers have been analyzed from the standpoints of combustion process stabilization and of ensuring the stability of flares. Among the factors of the firing process destabilization within the framework of analysis above mentioned, the following forms of unstable combustion/flame unstabilities have been considered: flashback, blow out or flame lifting, and the appearance of flame yellow tips. Bibl. 37, Fig. 11, Tab. 7.

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