• Polymer(Korea)
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• v.28 no.6
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• pp.478-486
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• 2004

Small intestinal submucosa (SIS) is consisted with collagen and glycosaminoglycan as well as some growth factors which can stimulate cell activity. Recently, it has been recognized that SIS has been successfully examined in the bio-medical application as biomaterials without xenograft immune-rejection response. We prepared native SIS sheets and acid treated SIS sheets by acetic acid with 1 or 5-layered sheets, respectively. The water uptake ability of native and acid treated SIS sheets was examined to evaluate the possibility as wound dressings. Morphologies of SIS sheets were characterized by SEM and the effects of various buffer solutions and different pH solutions on the water uptake ability were observed for 16 days. We observed that the acid treated SIS sheets had higher water uptake ability than native SIS sheets. Also, the water uptake ability of these was slightly higher in various buffers than distilled water. In conclusion, this study suggests that native and acid treated SIS sheets could be useful for the applications of wound dressing and biodegradable injectable materials.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.1-10
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• 2000

An experimental study regarding the effect of emulsions on RO is presented. Heavy oil was added to the sea water and the distilled water separately and treated for 30 minutes by a homogenizer to make emulsions. For the case of the sea water without heavy oil the permeate decreased from the beginning of the experiment. Chloride and conductivity increased with time, due to the fouling occurring as the suspended solids in the sea water accumulated on the membrane surface. Rejection rate of salt was 99.6~99.7%. As for the sea water containing heavy oil, the permeate decreased slowly from the beginning of the experiment. This result was the same for the case of the sea water only. However. chloride and conductivity increased significantly when heavy oil was added. In the second experiment with sea water containing heavy oil, the operation time of RO was reduced considerably. With addition of oil, the chloride increased greatly, while the permeate reduced comparatively. In the experiment where emulsion of $0.3{\sim}0.8mg/{\ell}$ was supplied to RO. oil concentration was about 10ppb in the permeate at the end of the experiment. In case of the distilled water containing heavy oil. the conductivity increased. However. the permeate reduced to 30% compared to the case of the sea water containing heavy oil. The case of sea water containing heavy oil showed an opposite result, but the effect of the addition of oil on RO was significant. Oil caused fouling of the RO and the contamination of the whole system, and as the result the system could not be operated properly. As a result the membrane capacity, the amount and water quality of permeate deteriorated significantly.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.215-221
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• 2015

Chicken breast meat samples were injected with marinade solution (salt, sugar, phosphate, monosodium glutamate, and nucleic acid) with or without 2% citrus peel extract (CPE), and then a subset were irradiated with a 1 or 2 kGy electron beam (EB) and/or subjected to high-pressure (HP) at 300 or 400 MPa. The initial total aerobic bacterial (TAB) count of the control sample was 4.57 log CFU/g and reached 7.17 log CFU/g after 3 days of storage at $4^{\circ}C$. The 2 kGy EB reduced the TAB count to 4.61 log CFU/g after 7 days. The 400 MPa HP treatment was also effective in reducing the TAB count, but the effect was slightly less than that noted with the 2 kGy EB. The CPE, in combination with the EB and HP, decreased the TAB count by 1.71 and 1.32 log CFU/g at the initial stage and further decreased the count during storage. The 2 kGy EB and the HP (300 and 400 MPa) increased the thiobarbituric acid-reactive substances value, whereas the CPE did not show an antioxidative effect. The EB and HP caused no difference in the sensory qualities. In contrast, the CPE decreased all sensory qualities tested. Sensory panelists commented that the samples with CPE were not in the "rejection" category but were "unfamiliar" for chicken breast meat. In conclusion, the EB was more effective than HP in improving the microbial quality of marinated chicken breast meat. The use of CPE in the marinade solution may synergistically increase the shelf life; however, it is necessary to develop an appropriate formulation to ensure that the sensory qualities are maintained.

• Membrane Journal
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• v.33 no.4
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• pp.149-157
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• 2023

Covalent organic frameworks (COFs) have shown promise in various applications, including molecular separation, dye separation, gas separation, filtration, and desalination. Integrating COFs into membranes enhances permeability, selectivity, and stability, improving separation processes. Combining COFs with single-walled carbon nanotubes (SWCNT) creates nanocomposite membranes with high permeability and stability, ideal for dye separation. Incorporating COFs into polyamide (PA) membranes improves permeability and selectivity through a synthetic interfacial strategy. Three-dimensional COF fillers in mixed-matrix membranes (MMMs) enhance CO₂/CH₄ separation, making them suitable for biogas upgrading. All-nanoporous composite (ANC) membranes, which combine COFs and metal-organic framework (MOF) membranes, overcome permeance-selectivity trade-offs, significantly improving gas permeance. Computational simulations using hypothetical COFs (hypoCOFs) demonstrate superior CO₂ selectivity and working capacity relevant for CO₂ separation and H₂ purification. COFs integrated into thin-film composite (TFC) and polysulfonamide (PSA) membranes enhance rejection performance for organic contaminants, salt contaminants, and heavy metal ions, improving separation capabilities. TpPa-SO₃H/PAN covalent organic framework membranes (COFMs) exhibited superior desalination performance compared to traditional polyamide membranes by utilizing charged groups to enable efficient desalination through electrostatic repulsion, suggesting their potential for ionic and molecular separations. These findings highlight COFs' potential in membrane technology for enhanced separation processes by improving permeability, selectivity, and stability. In this review, COF applied for the separation process is discussed.

• Membrane Journal
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• v.34 no.4
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• pp.205-215
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• 2024

The purpose of this paper was to preparation of organic solvent reverse osmosis (OSRO) membrane using a polyketone (PK) support. The PK support was prepared by non-solvent induced phase separation (NIPS) method, and a polyamide layer was interfacially polymerized on the PK support to fabricate OSRO membrane in the form of thin-film composite (TFC). After that, the surface and cross-sectional morphology of the OSRO membrane were analyzed, and the surface chemical structure of the membrane was analyzed. The water permeance and salt rejection of the OSRO membrane were about 1.28 LMH/bar and 99.0% respectively. The polyamide layer of the OSRO membrane was very stable during 1 day of organic solvent immersion, and the single organic solvent permeance trend was consistent with the organic solvent nanofiltration (OSN) membrane permeance model. The MWCO of the OSRO membrane is 240 g/mol in MeOH. The permeance and separation factor of the OSRO membrane for MeOH-toluene mixture were 200% and 60% higher than those of the commercial OSN membranes respectively.