The Development of Spark Discharges in Hydrogen

Streak photography has been used to supplement the earlier shutter photo. graphic investigation of Doran and Meyer (1967) using the same coaxial cable discharge circuit. Additional information has also been obtained from measurement of the potential distribution between the electrodes at two stages in the spark development. Redistribution of space charge is shown to give rise firstly to a transient diffuse glow discharge that has a close similarity with a normal d.c. glow discharge. It has also been shown that, even while the diffuse glow discharge expands, a partial constriction occurs in which most of the current flows along a narrow axial column. The resulting maximum in electron density eventually causes a rapid increase in dissociation of molecular hydrogen on the axis of the discharge brought about by a rise in the gas temperature. Owing to its greater electrical conductivity this axial column soon carries the entire current and the discharge becomes filamentary though still being maintained by a high cathode fall field, which exists until a sudden change in the cathode mechanism gives rise to the low voltage arc channel. Both the filamentary glow and arc columns are observed to expand according to an r cc ti law.

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Rotational and gas temperatures of molecular deuterium in a hollow cathode glow discharge

Journal of Research in Physics ◽

10.1515/jrp-2015-0002 ◽

2015 ◽

Vol 38-39 (1) ◽

pp. 11-22 ◽

Cited By ~ 2

Author(s):

G. Lj. Majstorović ◽

N. M. Šišović

Keyword(s):

Glow Discharge ◽

Hollow Cathode ◽

Low Voltage ◽

Rotational Temperature ◽

Energy Levels ◽

Optical Emission ◽

Gas Temperature ◽

Line Intensities ◽

Relative Line ◽

Deuterium Molecule

Abstract We report the results of optical emission spectroscopy measurements of rotational Trot and translational (gas) temperature of deuterium molecules. The light source was a low-voltage high-pressure hollow cathode (HC) glow discharge with titanium cathode operated in deuterium. The rotational temperature of excited electronic states of D2 was determined from the intensity distribution in the rotational structure of Q-branches of the two Fulcher-α diagonal bands: [ν′ = ν″ = 2] and [ν′ =ν″ = 3]. The population of the excited energy levels, determined from relative line intensities, was used to derive the radial distributions of the temperature of the excited and the ground state of the deuterium molecule.

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Topic-BERT: Detecting harmful information from social media

Intelligent Decision Technologies ◽

10.3233/idt-200094 ◽

2021 ◽

pp. 1-10

Author(s):

Wang Gao ◽

Hongtao Deng ◽

Xun Zhu ◽

Yuan Fang

Keyword(s):

Social Media ◽

Language Processing ◽

Topic Model ◽

Classification Performance ◽

Critical Research ◽

Short Text ◽

Additional Information ◽

Proposed Model ◽

Weight Calculation ◽

Two Stages

Harmful information identification is a critical research topic in natural language processing. Existing approaches have been focused either on rule-based methods or harmful text identification of normal documents. In this paper, we propose a BERT-based model to identify harmful information from social media, called Topic-BERT. Firstly, Topic-BERT utilizes BERT to take additional information as input to alleviate the sparseness of short texts. The GPU-DMM topic model is used to capture hidden topics of short texts for attention weight calculation. Secondly, the proposed model divides harmful short text identification into two stages, and different granularity labels are identified by two similar sub-models. Finally, we conduct extensive experiments on a real-world social media dataset to evaluate our model. Experimental results demonstrate that our model can significantly improve the classification performance compared with baseline methods.

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Vaporization of finely dispersed materials in arc and low-voltage spark discharges during quantitative spectral analysis of substances of arbitrary composition

Journal of Applied Spectroscopy ◽

10.1007/bf00613123 ◽

1970 ◽

Vol 13 (6) ◽

pp. 1549-1552

Author(s):

G. I. Kibisov ◽

V. A. Krzhizhanovskaya ◽

N. B. Kubasova ◽

V. E. Chuchina

Keyword(s):

Spectral Analysis ◽

Low Voltage ◽

Arbitrary Composition ◽

Spark Discharges ◽

Quantitative Spectral Analysis

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Validation of gas temperature measurements by OES in an atmospheric air glow discharge with water electrode using Rayleigh scattering

Plasma Sources Science and Technology ◽

10.1088/0963-0252/20/2/024002 ◽

2011 ◽

Vol 20 (2) ◽

pp. 024002 ◽

Cited By ~ 23

Author(s):

T Verreycken ◽

A F H van Gessel ◽

A Pageau ◽

P Bruggeman

Keyword(s):

Glow Discharge ◽

Rayleigh Scattering ◽

Temperature Measurements ◽

Gas Temperature ◽

Atmospheric Air

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The Influence of the Gas-Temperature on the Behaviour of the Positive Column of a Neon Glow Discharge and its Description by a Nonlinear Equivalent Circuit

Contributions to Plasma Physics ◽

10.1002/ctpp.2150350604 ◽

1995 ◽

Vol 35 (6) ◽

pp. 491-502

Author(s):

K.-D. Weltmann ◽

H. Unger ◽

H. Deutsch ◽

C. Wilke

Keyword(s):

Glow Discharge ◽

Equivalent Circuit ◽

Positive Column ◽

Gas Temperature ◽

Neon Glow Discharge

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Microelectrode-assisted low-voltage atmospheric pressure glow discharge in air

Physics of Plasmas ◽

10.1063/1.5004696 ◽

2017 ◽

Vol 24 (9) ◽

pp. 093519 ◽

Cited By ~ 4

Author(s):

Wenzheng Liu ◽

Shuai Zhao ◽

Jiangqi Niu ◽

Maolin Chai

Keyword(s):

Glow Discharge ◽

Atmospheric Pressure ◽

Low Voltage ◽

Atmospheric Pressure Glow Discharge ◽

Pressure Glow Discharge

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Gate Stacks for Low Voltage Ferroelectric Field Effect Devices Based on Pt/SBT/CeO2/Si(100)

MRS Proceedings ◽

10.1557/proc-596-437 ◽

1999 ◽

Vol 596 ◽

Author(s):

T. Haneder ◽

W. Hönlein ◽

H. Bachhofer ◽

M. Ullmann ◽

H. von Philipsborn ◽

...

Keyword(s):

Buffer Layer ◽

Low Voltage ◽

Interface State ◽

State Density ◽

Thin Layers ◽

Solution Deposition ◽

Additional Information ◽

Voltage Sweep ◽

Ferroelectric Layer ◽

Field Effect Devices

AbstractMETS (Metal Ferroelectric Insulator Semiconductor) capacitors were fabricated using CSD (Chemical Solution Deposition). Thin layers of CeO2 were deposited as an insulating buffer layer on Si(100) substrates and SrBi2Ta2O9 (SBT) was used as a ferroelectric layer. Pt electrodes were deposited by evaporation on top of the SBT layer. At constant SBT thickness the thickness of the CeO2 layer was varied to investigate the effects of the change in capacitance ratio between the ferroelectric and the buffer layer. XRD spectra were used to determine the phase of the SBT and the quality of the CeO2 layer. C(V) measurements showed the ferroelectric nature of the SBT. Additional information was provided by TEM and EDX analysis.Some samples showed a memory window as big as 1.6 Volt at a moderate voltage sweep from −3.5 to +3.5 Volt. Interface state density is approximately 2×1011/cm2 eV and remanent polarization was found to be in the range of 0.3 μC/cm2. These results are already very promising in terms of fabricating a Ferroelectric FET. Some basic considerations with respect to the development of IT memory cells on the basis of this kind of transistor will also be presented.

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