• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.578-590
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• 2015

The present study examines the influence of slurry composting and biofiltration liquid fertilizer (SCBLF) treatment on the biomass characteristics of yellow poplar, and the optimization of organosolv pretreatment for sugar production. After SCBLF treatment, total exchangeable cation contents of yellow poplar was increased from $3.1g\;kg^{-1}$ to $4.4g\;kg^{-1}$, and as a result, biomass production of yellow poplar was also enhanced by 82.3%. Organosolv pretreatment was conducted with three independent variables: 1) reaction temperature: $133.2^{\circ}C$ to $166.8^{\circ}C$; 2) acid concentration: 0.2% to 1.8%; and 3) reaction time: 1.6 min to 18.4 min. Reaction temperature was the most significant variable in water insoluble solid (WIS) recovery rate. High overall sugar yield was attained from pretreatment conditions approximately 50% of WIS recovery rate, and the highest overall glucose yield (44.0%) was achieved from pretreatment at $140^{\circ}C$ with 1.5% acid concentration for 5 min. Consequently, 21.1% of glucose and 5.8% of xylose were produced from the organosolv pretreatment of SCBLF-treated 8-year-old yellow poplar.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.141-147
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• 2001

For the preparation of calcium carbonate particles from aqueous $Ca(OH)_2$ slurry, carbonation reaction of aqueous $Ca(OH)_2$ slurry was carried out by batch method the $CO_2$ into reactor filled with aqueous slurry of $Ca(OH)_2$. The concentration of $Ca(OH)_2$ varies from 1.00 to 7.00wt%, reactor temperature at 20 and $40^{\circ}C$, and reactor pressure from atmospheric pressure to $6.0kg_f/cm^2$. Crystal structure of calcium carbonate was of calcite, the particle size were about $0.05{\sim}2.0{\mu}m$, and the particle shape was cubic and spindle. When reactor temperature was higher, particle size of calcium carbonate was bigger and particle shape was varied, but reaction rate was increased. When reactor pressure was higher, particle size of calcium carbonate was smaller, particle shape was cubic, and reaction rate was increased.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1229-1235
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• 2010

With the increase of human activities since the Industrial Revolution, atmospheric greenhouse gas (GHG) concentration has increased, which is believed the cause of climate change. Methane ($CH_4$) fluxes were measured at two commercial swine barns (Jarvis and Guelph) with a four tower micrometeorological mass balance method. Two and three separate measurements were conducted at Jarvis and at Guelph, respectively. In the Jarvis experiments from May to July, mean $CH_4$ flux ($490.4{\mu}g/m^2/s$) during daytime was lower than that during nighttime ($678.0{\mu}g/m^2/s$) (p<0.05), which would be caused by break of slurry temperature stratification. In the Guelph experiment from January to April, mean $CH_4$ flux ($62.9{\mu}g/m^2/s$) during daytime was higher than that during nighttime ($39.0{\mu}g/m^2/s$) (p<0.05), which would be generated by high slurry temperature at 3 cm depth after April 6. Slurry temperature stratification in the Guelph experiment would happen from January to March.

• Journal of Powder Materials
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• v.18 no.4
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• pp.327-331
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• 2011

In order to fabricate the porous metal with controlled pore characteristics, unique processing by using metal oxide powder as the source and camphene as the sublimable material is introduced. CuO powder was selected as the source for the formation of Cu metal via hydrogen reduction. Camphene-based CuO slurry, prepared by milling at $47^{\circ}C$ with a small amount of dispersant, was frozen at $-25^{\circ}C$. Pores were generated subsequently by sublimation of the camphene. The green body was hydrogen-reduced at $200^{\circ}C$ for 30 min, and sintered at $500-700^{\circ}C$ for 1 h. Microstructural analysis revealed that the sintered Cu showed aligned large pore channels parallel to the camphene growth direction, and fine pores are formed around the large pore. Also, it showed that the pore size was controllable by the slurry concentration.

• Journal of the Korean Applied Science and Technology
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• v.19 no.4
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• pp.251-257
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• 2002

Liquid-phase methanol synthesis via methyl formate using coal-derived syngas was carried out in a bench-scale(diameter 173 mm and dispersion height 1200 mm) slurry bubble column reactor(SBCR) Under the condition of $180^{\circ}$. 61 atm, 30 L/min, $H_{2}$/CO=2 and a slurry mixture of 2 kg of copper chromite and 0.5 kg of $KOCH_{3}$ suspended in 14 L of methanol, the per pass conversions of syngas is 6 %, maximum concentration of methyl formate 3.088 mol% and maximum synthesis, rate of methanol 0.8 gmole/kg ${\cdot}$ hr. It is a significant evidence that copper chromite powder as heterogeneous catalyst didn't active for the hydrogenolysis of methyl formate to methanol, resulting copper chromite powder was not efficiently suspended in a slurry mixture. To enhance the hydrogenolysis of methyl formate in liquid-phase methanol synthesis process, the designed SBCR have need to use the higher specific gravity solvent and/or decrease the catalyst particle size.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.9
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• pp.787-792
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• 2005

Chemical mechanical polishing(CMP) has become the process of choice for modem semiconductor devices to achieve both local and global planarization. CMP is a complex process which depends on numerous variables such as macro, micro and nano-geometry of pad, relative velocity between pad and wafer stiffness and dampening characteristics of pad, slurry, pH, chemical components of slurry, abrasive concentration, abrasive size, abrasive shape, etc. Especially, an oxidizer of chemical components is very important remove a target material in metal CMP process. This paper introduces the effect of oxidizer such as $H_2O_2,\;Fe(NO_3)_3\;and\;KIO_3$ in slurry for tungsten which is used in via or/and plug. Finally the duplex reacting mechanism of $oxidizer(H_2O_2)$ through adding the $catalyst(Fe(NO_3)_3)$ could acquire the sufficient removal rate in tungsten CMP.

• Journal of the Korean Ceramic Society
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• v.44 no.10
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• pp.574-579
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• 2007

Porous $Al_2O_3$ ceramics were prepared by the gelcasting foams method (a slurry foaming process) with acrylamide monomer. The foaming and gelation behavior was investigated with the parameters such as the type and concentration of surfactant, solid loading of slurry, and the concentrations of initiator and catalyst. Density, porosity, microstructure, and strength of the green and sintered samples were characterized. Of the four kinds of surfactants tested, Triton X-114 showed the highest foaming ability for the solid loading of 55-30 vol%. The gelation condition giving the idle time off min was found to set the foamed structure without significant bubble enlargement and liquid lamella thinning. The green samples were fairly strong and machinable and showed maximum strength of 2.4 MPa in diametral compression. The sintered samples showed densities of 10-36% theoretical (i.e. porosity 90-64%) with a highly interconnected network of spherical pores with sizes ranging from 30 to $600{\mu}m$. The pore size and connectivity increased but the cell strut thickness decreased with decreasing the solid loading. Flexural strength of 37.8-1.7 MPa was obtained for the sintered samples.

• Journal of Environmental Health Sciences
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• v.31 no.5 s.86
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• pp.423-430
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• 2005

This research was performed to evaluate the effectiveness of one- and dual-stage recycled-water systems in slurry bioreactor treatment for coal tar-contaminated soil. Silty loam soil was used for this research. Coal tar and 14 target PAHs (Polycyclic Aromatic Hydrocarbons) concentration in the soil were determined with gas chromatography. There was no significant difference between removal efficiencies of one- and dual-stage recycled water systems in case of about 4,000 mg coar tar/kg. However, the dual-stage system increased significantly the removal efficiency in case of about 20,000 mg coar tar/kg and the first-order kinetic constant of the system was over 1.5 times higher than that of one-stage recycled water system. 3-Ring compounds in PAHs was removed completely within 30 days of operation. Coar tar was removed in over 96% through biodegradation and removed in about 4% by evaporation. High correlation coefficient($r^2=0.91$) was found between water solubility and removal efficiency of the cyclic compounds.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.711-719
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• 2006

The effluent from anaerobic digestion process of slurry-type piggery waste has a characteristic of very low C/N ratio. Because of high nitrogen content, it is necessary to evaluate nitrogen removal alternative rather than conventional nitrification-denitrification scheme. In this study, two parallel treatment schemes of SBR-like partial nitritation reactor coupled with anaerobic ammonium oxidation (ANAMMOX) reactor, and a nitritation reactor followed by nitrite denitrification process were evaluated with a slurry-type piggery waste. The feed to reactors adjusted with various $NH_4-N$ and organics concentration. The nitrite accumulation was successfully accomplished at the loading rate of about $1.0kgNH_4-N/m^3-day$. The $NO_2-N/NH_4-N$ ratio 1~2.6 in nitritated effluent that operated at HRT of 1 day indicated that SBR-like partial nitritation was applicable to ANAMMOX operation. Meanwhile, the nitrite accumulation of 87% was achieved at SBR operated with HRT of 3 days and $0.4mgO_2/L$ for denitritation. Experimental results further suggested that HRT (SRT) and free ammonia(FA) rather than DO are an effective control parameter for nitrite accumulation in piggery waste.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.1
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• pp.12-16
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• 2005

Chemical mechanical polishing (CMP) process is one of the most useful methods for improving the surface roughness of films. The effects of CMP on the surface morphology of WO$_3$ films prepared by RF sputtering system were investigated in this paper. A removal rate of films increased, and the uniformity performance of surface decreased with the addition of an oxidizer to the tungsten slurry. Non-uniformity performance of surface was superior as its value was below 5 % when oxidizers of 5.0 vol% and 2.5 vol%, respectively, were added to the tungsten slurry. The optimized oxidizer concentration, reflected both the improved roughness values and hillock-free surface with the good uniformity performance, was 5.0 vol% as an atomic force microscopy(AFM) analysis of thin film topographies. Our CMP results will be a useful reference for advanced technology of thin films for gas sensor applications in the near future.