• Transactions of the Korean hydrogen and new energy society
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• v.20 no.2
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• pp.168-178
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• 2009

To check feasibility of SEWGS(Sorption Enhanced Water Gas Shift) system, conceptual design and sensitivity analysis of operating variables have been investigated based on a design program of two-interconnected fluidized bed. Based on the conceptual design results, the optimum configuration for SEWGS was considered. Among three configurations, bubbling beds system was selected as the best configuration. Process design results indicate that the SEWGS system is compact and feasible. Based on the selected operating conditions, the effects of variables such as pressure, $CO_2$ capture capacity, solid inventory, CO conversion and $CO_2$ capture efficiency have been investigated as well.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.1
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• pp.1-11
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• 2007

To check feasibility of SMART(Steam Methane Advanced Reforming Technology) system, conceptual design and sensitivity analysis of operating variables have been performed based on the design program of two-interconnected fluidized beds. Among three configurations of two-interconnected fluidized beds systems, the bubbling-bubbling system was selected as the best configuration. Process design results indicate that the SMART system is compact and feasible. Based on the selected operating conditions, the effects of variables such as process capacity, pressure, and weight percent of $CO_2$ absorbable component have been investigated as well.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.935-946
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• 2014

This paper investigates the noise transmission performance of industrial mufflers widely used in ships based on the CAE modeling and simulation. Since the industrial mufflers have very complicated internal structures, the conventional Transfer Matrix Method (TMM) is of limited use. The CAE modeling and simulation is therefore required to incorporate commercial softwares: CATIA for geometry modeling, MSC/PATRAN for FE meshing and LMS/SYSNOISE for analysis. Main sources of difficulties in this study are led by complicated arrangement of reactive elements, perforated walls and absorption materials. The reactive elements and absorbent materials are modeled by applying boundary conditions given by impedance. The perforated walls are modeled by applying the transfer impedance on the duplicated node mesh. The CAE approach presented in this paper is verified by comparing with the theoretical solution of a concentric-tube resonator and is applied for industrial mufflers.

• Membrane Journal
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• v.30 no.3
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• pp.173-180
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• 2020

As the demand for fossil fuels continues to increase worldwide, carbon dioxide (CO₂) concentration in the air has increased over the centuries. The way to reduce CO₂ emissions to the atmosphere, carbon capture and sequestration (CCS) technology have been developed that can be applied to power plants and factories, which are primary emission sources. According to the climate change mitigation policy, direct air capture (DAC) in air, referred to as "negative emission" technology, has a low CO₂ concentration of 0.04%, so it is focused on adsorbent research, unlike conventional CCS technology. In the DAC field, chemical adsorbents using CO₂ absorption, solid absorbents, amine-functionalized materials, and ion exchange resins have been studied. Since the absorbent-based technology requires a high-temperature heat treatment process according to the absorbent regeneration, the membrane-based CO₂ capture system has a great potential Membrane-based system is also expected for indoor CO₂ ventilation systems and immediate CO₂ supply to smart farming systems. CO₂ capture efficiency should be improved through efficient process design and material performance improvement.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.1
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• pp.21-28
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• 2009

Physico-chemical characteristics of the Ca-based and Na-based dry sorbents were compared using thermo-gravimetric analysis (TGA) and temperature programmed desorption (TPD) methods. The studied characteristics were thermal stability, sulfur dioxide ($SO_2$) absorption capacity and absorption rate at $250^{\circ}C$ which is a typical temperature before a fabric filter, and $SO_2$ absorption capacity at an ambient temperature. Calcium hydroxide ($Ca(OH)_2$) started to decompose into calcium oxide (CaO) at $390^{\circ}C$ and completed at 480~$500^{\circ}C$, showing 76% of an original $Ca(OH)_2$ weight. Sodium bicarbonate ($NaHCO_3$) also converted to sodium carbonate ($Na_2CO_3$) between $95^{\circ}C$ and $190^{\circ}C$, decreasing the weight to 63% of its initial weight. Among four sorbents tested at $250^{\circ}C$, sodium carbonate had the highest capacity, absorbing 0.35 g $SO_2$/g sorbent. Calcium oxide and calcium hydroxide followed that showing 0.156 g and 0.065 g $SO_2$ absorption per absorbent respectively. Ca-based absorbents showed slower rate than sodium carbonate because of initial stagnant step. However, calcium hydroxide caught more $SO_2$ than sodium carbonate at ambient temperature. From this work, it can be concluded that Ca-based absorbent is a proper sorbent for $SO_2$ treatment at low temperature and sodium carbonate, at high temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2557-2564
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• 2009

In this study, a muffler for the super heavy machinery in the 70 ton class is developed. Developing process relies on experimental and rule of thumb approach. Various muffler internal structures consisting of partition plates, perforated and non-perforated through pipes, and absorbent are tried and compared for the transmission loss performance. Based on the experimental results, the best combination and locations of the internal acoustic components which affects the muffler performance are determined.

• Macromolecular Research
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• v.14 no.3
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• pp.324-330
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• 2006

Four different molecularly imprinted polymers (MIPs) were prepared using resveratrol as the template, methacrylic acid (MAA) or acrylamide (AA) as functional monomers, 2,2-azobisisobutyronitrile (AIBN) as the initiator, and thermo- or photo-induced polymerization. The ability of the different polymers to rebind selectively not only the template but also other phenols was evaluated. In parallel, the influence of the different templates and functional monomers used during polymer syntheses on the performance of the obtained MIPs was also studied through different rebinding experiments. The binding ability and selectivity of the polymer were studied by static balance method and Scatchard analysis. It was concluded that AA-based polymer by photo-induced polymerization presents the best properties to be used as a selective absorbent for the extraction of resveratrol.

• Asian Journal of Turfgrass Science
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• v.22 no.1
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• pp.75-84
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• 2008

This study was carried out to examine the effects of cornstarch-based absorbent polymer (CAP) on the growth of cool season turfgrasses in sand-based soil mixture. Kentucky bluegrass + perennial ryegrass mixtures seeded at May 18 in 2006 on sand-based soil mixture. Sand + peat (5%, v/v), sand + CAP $20g{\cdot}m^{-2}$, sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v), and sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) mixtures were compared. Ground coverage of sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v), and sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) treatments showed 50% at a month after seeding. But the coverage of sand + peat (5%, v/v), sand + CAP $20g{\cdot}m^{-2}$ resulted in 36.7%. Mixing of CAP with sand was considered to be efficient method for increasing ground coverage as much as peat. Dry weight of turfgrass tiller at sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v), and sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) were also significantly higher than sand + peat (5%, v/v), sand + CAP $20g{\cdot}m^{-2}$ mixtures at a month after seeding. Soil water retention at the sand + CAP $20g{\cdot}m^{-2}$, sand + CAP $40g{\cdot}m^{-2}$ + peat (5%, v/v) mixing were lower than sand + peat (5%, v/v) and sand + CAP $20g{\cdot}m^{-2}$ + peat (5%, v/v) during the dry periods. From the results, the mixing of CAP with sand is useful to increased ground coverage of kentucky bluegrass and perennial ryegrass.

• Carbon letters
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• v.26
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• pp.1-10
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• 2018

Biochar obtained from the thermal conversion of biomass has high potential as a substitute material for activated carbon and other carbon-based materials because it is economical, environmentally friendly, and carbon-neutral. The physicochemical properties of biochar can also be controlled by a range of activation methods such as physical, chemical, and hydrothermal treatments. Activated biochar can be used as a catalyst for the catalytic pyrolysis of a biomass and as an absorbent for the removal of heavy metal ions and atmospheric pollutants. The applications of biochar are also expanding not only as a key component in producing energy storage materials, such as supercapacitors, lithium ion batteries, and fuel cells, but also in carbon capture and storage. This paper reviews the recent progress on the activation of biochar and its diverse present and future applications.

• Journal of the Korean Ceramic Society
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• v.53 no.1
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• pp.68-74
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• 2016

In this study, the fabrication of zeolite combined activated carbon spherical samples was carried out as follows. Briefly, ZSM-5 zeolite and activated carbon were composed as main absorbent materials; by controlling the weight percentage of zeolite and binder materials, a series of spherical samples (AZP 4, 6, 8) were prepared. These spherical samples were characterized by BET, XRD, SEM, EDX, and pressure drop; benzene and iodine adsorption tests, bactericidal effect test, and ignition temperature test were also performed. The adsorption capability was found to depend on the BET surface area; the spherical samples AZP6 with high BET surface area of $1011m^2/g$ not only exhibited excellent removal effects for benzene (24.9%) and iodine (920mg/g) but also a good bactericidal effect. The enhanced ignition temperature may be attributed to the homogeneous dispersion conditions and the proper weight percentage ratio between zeolite and activated carbon.