Stable Molecules in N<sub>2</sub>–H<sub>2</sub>Plasmas Measured Using a Quartz Sensor

Suzuki, Atsushi; Asahina, Shuichi

doi:10.7567/jjap.52.11nc04

Cited by 7 publications

(4 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Gómez-Ramírez et al [110] found that the best energy efficiency was achieved with the feed gas ratio equal or close to the stoichiometric ratio. This conclusion is in line with many previously reported researches [110][111][112][113][114]. On the other hand, other studies have shown that a higher N 2 /H 2 is favoured for the ammonia production [107,112,[115][116][117][118][119].…”

Section: Direct Synthesis Of Ammonia From N 2 and Hsupporting

confidence: 92%

Recent Progress of Plasma-Assisted Nitrogen Fixation Research: A Review

et al. 2018

View full text Add to dashboard Cite

Nitrogen is an essential element to plants, animals, human beings and all the other living things on earth. Nitrogen fixation, which converts inert atmospheric nitrogen into ammonia or other valuable substances, is a very important part of the nitrogen cycle. The Haber-Bosch process plays the dominant role in the chemical nitrogen fixation as it produces a large amount of ammonia to meet the demand from the agriculture and chemical industries. However, due to the high energy consumption and related environmental concerns, increasing attention is being given to alternative (greener) nitrogen fixation processes. Among different approaches, plasma-assisted nitrogen fixation is one of the most promising methods since it has many advantages over others. These include operating at mild operation conditions, a green environmental profile and suitability for decentralized production. This review covers the research progress in the field of plasma-assisted nitrogen fixation achieved in the past five years. Both the production of NOx and the synthesis of ammonia are included, and discussion on plasma reactors, operation parameters and plasma-catalysts are given. In addition, outlooks and suggestions for future research are also given.

show abstract

Section: Direct Synthesis Of Ammonia From N 2 and Hsupporting

confidence: 92%

Recent Progress of Plasma-Assisted Nitrogen Fixation Research: A Review

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The experimental apparatus used in this study has been described in detail in our previous work. 7) Essentially, our plasma chamber is a conventional one that includes parallel plasma electrodes for rf (13.56 MHz) discharges.…”

Section: Methodsmentioning

confidence: 99%

“…Quartz sensor (Q-sensor) measurement can detect changes in the gas compositions of plasmas because the pressureand temperature-normalized Q-sensor output (NQO) depends only on the viscosity and molecular weight of the measured gas. [1][2][3][4][5][6][7][8] Q-sensor measurement can selectively derive only the information on stable gas molecules in plasmas when a mesh cover is used to prevent reactive chemical species in the plasmas from reaching the quartz oscillator, which is a sensing device installed in the Q-sensor. Q-sensor measurement is a useful plasma diagnostic method, although it cannot yield information on each chemical species in plasmas, which can be derived by gas analysis using a mass spectrometer.…”

Section: Introductionmentioning

confidence: 99%

Dependence of composition of stable molecules in N₂–H₂plasmas on nitrogen gas flow rate ratio measured using a quartz sensor

Suzuki¹,

Asahina²

2014

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Compositions of stable molecules in N 2 -H 2 plasmas measured using a quartz sensor (Q-sensor) were compared with those measured using a quadrupole mass spectrometer (QMS) under various nitrogen gas flow rate ratio to determine the applicability of Q-sensor measurement to N 2 -H 2 plasmas. The nitrogen flow rate ratio dependence of the Q-sensor results obtained 20 mm from the edge of the plasma electrodes (Z = 20 mm) tended to agree more qualitatively with the NH 3 density measured by QMS compared with those measured at 70 mm. For pure nitrogen or hydrogen plasma, the results measured at Z = 20 mm differed from those of gas analyses using QMS. The analysis indicated that Q-sensor results obtained near discharges with various nitrogen flow rate ratios reflect information on stable molecules such as N 2 , H 2 , and NH 3 but yield information on other stable molecules or other chemical species in pure N 2 and H 2 plasmas.

show abstract

“…In addition, ρ can be expressed as a product of the molecular weight (M) and pressure (P) of the gas. Therefore, the output from a quartz oscillator depends on ç and M. This means that the Qgauge can detect not only the change in pressure, but also the content of the gas, making it applicable to hydrogen sensing, hydrogen concentration measurements, partial concentration measurements of binary gases, and plasma diagnostics [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Humidity Calibration for a Pressure Gauge Using a Temperature-Stable Quartz Oscillator

Suzuki

2016

Applied Science and Convergence Technology

Self Cite

View full text Add to dashboard Cite

Humidity calibration for a temperature-stable quartz oscillator (TSQO) was investigated to exclude the influences of relative humidity on the TSQO output in order to use the corresponding devices outdoors. The TSQO output is a voltage that is inversely proportional to the electric impedance of the quartz oscillator, which depends on the viscosity and density of the measured gas. The TSQO output was humidity calibrated using its humidity dependence, which was obtained by varying the relative humidity (RH) from 0 to 100 RH% while other conditions were kept constant. The humidity dependencies of the TSQO output were fit by a linear function. Subtracting the change in the TSQO output induced by the change in humidity, calculated with the function from the experimentally measured TSQO output for a range of 0-100RH%, eliminated the influence of humidity on the TSQO output. The humidity calibration succeeded in reducing the fluctuations of the TSQO output from 0.4-3% to 0.1-0.3% of the average values for a range of 0-100RH%, at constant temperatures. The necessary stability of the TSQO output for application in hydrogen sensors was below one-third of the change observed for a hydrogen leakage of 1 vol.% hydrogen concentration, corresponding to 0.33% of the change in each background. Therefore, the results in this study indicate that the present humidity calibration effectively suppresses the influence of humidity, for the TSQO output for use as an outdoor hydrogen sensor.

show abstract

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Cited by 7 publications

References 35 publications

Recent Progress of Plasma-Assisted Nitrogen Fixation Research: A Review

Recent Progress of Plasma-Assisted Nitrogen Fixation Research: A Review

Dependence of composition of stable molecules in N₂–H₂plasmas on nitrogen gas flow rate ratio measured using a quartz sensor

Humidity Calibration for a Pressure Gauge Using a Temperature-Stable Quartz Oscillator

Contact Info

Product

Resources

About

Stable Molecules in N2–H2Plasmas Measured Using a Quartz Sensor

Cited by 7 publications

References 35 publications

Recent Progress of Plasma-Assisted Nitrogen Fixation Research: A Review

Recent Progress of Plasma-Assisted Nitrogen Fixation Research: A Review

Dependence of composition of stable molecules in N2–H2plasmas on nitrogen gas flow rate ratio measured using a quartz sensor

Humidity Calibration for a Pressure Gauge Using a Temperature-Stable Quartz Oscillator

Contact Info

Product

Resources

About

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Dependence of composition of stable molecules in N₂–H₂plasmas on nitrogen gas flow rate ratio measured using a quartz sensor