Effects of methane flow rate on the optical properties and chemical bonding of germanium carbon films deposited by reactive sputtering

Vacuum ◽  
2013 ◽  
Vol 90 ◽  
pp. 75-79 ◽  
Author(s):  
Xing-Sen Che ◽  
Zheng-Tang Liu ◽  
Yang-Ping Li ◽  
Ning Wang ◽  
Zuo Xu
Keyword(s):  
Optical Properties ◽  
Flow Rate ◽  
Chemical Bonding ◽  
Reactive Sputtering ◽  
Carbon Films ◽  
Methane Flow Rate ◽  
Methane Flow

Development and Analysis of Robust Anti-Wear Design of a-C:Zr Films by Taguchi Methods

2011 ◽  
Vol 189-193 ◽  
pp. 3647-3652
Author(s):  
Wesley Huang ◽  
Ching Jyi Chen ◽  
Ming Der Jean
Keyword(s):  
Friction Coefficient ◽  
Bias Voltage ◽  
Flow Rate ◽  
High Hardness ◽  
Pulse Frequency ◽  
Taguchi Methods ◽  
Control Factors ◽  
Methane Flow Rate ◽  
Percent Contribution ◽  
Methane Flow

Amorphous carbon (a:C-H) coatings with high hardness and low friction coefficient are widely applied in die and mold industries. Zirconium-containing a:C-H (a-C:Zr) coatings with double interlayered Zr/ZrC were deposited by unbalanced magnetron sputtering system. A L18 orthogonal array experiment was designed to investigate the effect of process parameter on the friction coefficient of deposited films. Control factors, such as methane flow rate, bias voltage, sputtering frequency, zirconium target current and work distance were schematized for experiments. The experimental results show that zirconium target current exhibits about 45% percent contribution in analysis of variance, and the friction coefficient of a-C:Zr coatings range from 0.13 to 0.31. From effect plots, the optimum parameters are bias voltage at -70V, zirconium target current at 0.6 A, pulse frequency at 90 kHz, methane flow rate at 6 sccm and work distance at 15 cm. The friction coefficient performs as 0.106 in verification experiments. Meanwhile, one-by-one factorial experiments were also carried out and discussed in this study.

Diamond-like carbon deposited by plasma technique as a function of methane flow rate

2010 ◽  
Vol 19 (7-9) ◽  
pp. 756-759 ◽  
Author(s):  
G.A. Viana ◽  
E.F. Motta ◽  
M.E.H.M. da Costa ◽  
F.L. Freire ◽  
F.C. Marques
Keyword(s):  
Flow Rate ◽  
Diamond Like Carbon ◽  
Plasma Technique ◽  
Methane Flow Rate ◽  
Methane Flow

Luminescent Properties of SiC Thin Film Deposited by VHF-PECVD: Effect of Methane Flow Rate

2017 ◽  
Vol 268 ◽  
pp. 239-243
Author(s):  
Emilly Albert Alim ◽  
Muhammad Firdaus Omar ◽  
Abd. Khamim Ismail
Keyword(s):  
Thin Film ◽  
Flow Rate ◽  
Quantum Confinement Effect ◽  
Chemical Vapour ◽  
Blue Emission ◽  
Light Sources ◽  
Very High Frequency ◽  
Blue Emission Band ◽  
Methane Flow Rate ◽  
Methane Flow

Bulk silicon carbide (SiC) as light emitter is less efficient due to its indirect bandgap. Therefore, nanosized SiC thin film fabrication approach enable emission wavelength shifts due to spatial confinement. The result of luminescent study of SiC thin film deposited via very high frequency plasma-enhanced chemical vapour deposition (VHF-PECVD) are presented. Precursor gasses used were silane and methane. Methane flow rate was varied from 8 sccm to 20 sccm while other parameters were maintained. Raman spectral analysis denotes the quantum confinement effect occurrence in proportion to the methane flow rate increment. The luminescence properties of the deposited SiC thin film ranging from highly green emission (~518 nm) to highly UVB emission (~294 nm) dominant luminescence. Broad blue emission band shifted toward higher wavelength with smaller FWHM as methane flow rate is increased. This results enable the possibility of luminescent SiC thin film applications in photonics and electronic integration as blue light sources.

scholarly journals A Method to Accurately Determine the Methane Enrichment Zone of a Longwall Coal Mine

Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Guorui Feng ◽  
Ao Zhang ◽  
Shengyong Hu ◽  
Xiangqian Guo ◽  
Chao Li ◽  
...  
Keyword(s):  
Flow Rate ◽  
Coal Mine ◽  
Methane Concentration ◽  
Longwall Mining ◽  
Longwall Face ◽  
Shanxi Province ◽  
Large Numbers ◽  
Methane Flow Rate ◽  
Low Levels ◽  
Methane Flow

Large numbers of gobs are produced as a result of underground longwall mining, and a large amount of these gobs is known to contain methane gas reserves. The efficient drainage of these methane resources is directly dependent on accurately determining the methane enrichment zone (MEZ) in longwall mining gobs. In this study, a method for accurately determining the MEZ within the zone of interconnected fractures, which utilized a surface directional borehole (SDB) technique, was proposed. The SDB was designed and implemented in a longwall gob located in the Sihe Coal Mine in China’s Shanxi Province. The trajectory of the SDB constantly varied in the different overlying stratum layers and locations above the gob. The methane flow rate and concentration from the SDB, along with the methane concentration in the upper corner of the longwall face, were monitored and obtained as the longwall face advanced. Then, by analyzing the acquired data of the different horizontal and vertical positions of the SDB, the accurate locations of the MEZ within the zone of interconnected fractures were determined. There were the methane decrease zone (MDZ) and methane shortage zone (MSZ) below and above the MEZ, respectively. The results showed that in the MEZ, both the methane flow rate and concentration displayed slight decreasing trends and maintained high levels as the distance from the roof of the coal seam increased. In the MDZ, a sharp decline was observed in the methane flow rate. However, a relatively high methane concentration had still been maintained. In the MSZ, both the methane flow rate and concentration displayed dramatic fluctuation and relatively low levels. The average methane flow rates in the MEZ were determined to be 1.3 and 1.6 times higher than those in the MDZ and MSZ, respectively.

scholarly journals The results of experimental research of the parameters of methane capturing by local degassing wells in the undermining area

2019 ◽  
Vol 109 ◽  
pp. 00097
Author(s):  
Kostiantyn Sofiiskyi ◽  
Oleksandr Petukh
Keyword(s):  
Experimental Research ◽  
Flow Rate ◽  
Methanotrophic Bacteria ◽  
Technological Parameters ◽  
Methane Flow Rate ◽  
Mining Conditions ◽  
Subsequent Application ◽  
Mine Roadway ◽  
Basic Parameters ◽  
Methane Flow

The article is devoted to the analysis of the results of the mine instrumental measurements of the local degassing system of the m3 seam on the horizon of 1100 m of the mine named. V.M. Bazhanov to establish the basic rational parameters with the subsequent application of the biotechnological method of reducing the concentration of methane. As a result of mine instrumental measurements (vacuum-gas surveys at the borehole heads), the parameters of the degassing process (methane flow rate at the borehole heads and the average vacuum on them), technological parameters (angle of turn and tilt of wells, their length), well flow rate efficiency from the distance to the bottom of the longwall and the displacement of the undermined rocks. Establishing the basic parameters of degassing will allow you to quickly manage the flow rate of wells and underpressure at their mouths, taking into account the specific mining and geological and mining conditions. The use of biofilters allows controlling the concentration of methane in the atmosphere of mine roadway by methanotrophic bacteria.

Sign in / Sign up

Export Citation Format

Share Document