• Journal of Korean Society of Water and Wastewater
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• v.20 no.4
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• pp.509-518
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• 2006

Although final water of domestic water treatment plants almost contains highly corrosive characteristics, the countermeasures for eliminating internal corrosion of pipeline system have not been conducted yet by controlling water quality in plants. The technologies of internal corrosion control are to control water quality parameters(pH, Alkalinity, and Calcium Hardness etc.) and to use corrosion inhibitor. Under the conditions of domestic water treatment, first of all, the technologies of adjusting water quality parameters has to be considered. Otherwise, The technology of using corrosion inhibitor is favorably thought to be applied with the technology of adjusting water quality parameters in accordance with the result of availability for water treatment process. Since the technology of adjusting water quality parameter influences on other water treatment processes, the guideline of water quality management to be apt for water quality characteristic is required to be estabilished. While the selection of proper chemicals and technologies is dependent upon the raw water characteristics and water treatment process, typically, the technology of $Ca(OH)_2$ & $CO_2$ additions is considered more effective than other technologies in order to adjust pH and Alkalinity, increase $Ca^{2+}$ and form $CaCO_3$ film

• Membrane and Water Treatment
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• v.3 no.3
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• pp.181-200
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• 2012

At present water crisis is not an issue of scarcity, but of access. There is a growing recognition of the need for increased access to clean water (drinkable, agricultural, industrial use). An encouraging number of innovative technologies, systems, components, processes are emerging for water-treatment, including new filtration and disinfectant technologies, and removal of organics from water. In the past decade many methods have been developed. The most important membrane-based water technologies include reverse osmosis (RO), ultrafiltration (UF), microfiltration (MF), and nanofiltration. Beside membrane based water-treatment processes, other techniques such as advanced oxidation process (AOP) have also been developed. Some unconventional water treatment technology such as magnetic treatment is also being developed.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.599-606
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• 2005

Arsenic is a significantly toxic contaminant in groundwater in many countries. Numerous treatment technologies have been developed to remove arsenic from groundwater. The USEPA recommends several technologies as the best available technology (BAT) candidates for the removal of arsenic. Based on the USEPA classification, arsenic treatment technologies can be divided into four technologies such as precipitation, membrane, ion exchange, and adsorption technology. The recent amendment of arsenic drinking water standard from 50 to $10{\mu}g/L$ in the United States have impacted technology selection and application for arsenic removal from arsenic contaminated groundwater. Precipitation technology is most widely used to treat arsenic contaminated groundwater and can be applied to large water treatment facility. In contrast, membrane, ion exchange, and adsorption technologies are used to be applied to small water treatment system. Recently, the arsenic treatment technology in the United States and Europe move towards adsorption technology to be applied to small water treatment system since capital and maintenance costs are relatively low and operation is simple. The principals of treatment technologies, effect factors on arsenic removal, arsenic treatment efficiencies of real treatment systems are reviewed in this paper.

• Macromolecular Research
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• v.12 no.4
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• pp.367-373
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• 2004

We have developed a rigorous heat treatment method to improve the biocompatibility of chitosan as a tissue-engineered scaffold. The chitosan scaffold was prepared by the controlled freezing and lyophilizing method using dilute acetic acid and then it was heat-treated at 110$^{\circ}C$ in vacuo for 1-3 days. To explore changes in the physicochemical properties of the heat-treated scaffold, we analyzed the degree of deacetylation by colloid titration with poly(vinyl potassium sulfate) and the structural changes were analyzed by scanning electron microscopy, Fourier transform infrared (FT-IR) spectroscopy, wide-angle X-ray diffractometry (WAXD), and lysozyme susceptibility. The degree of deacetylation of chitosan scaffolds decreased significantly from 85 to 30% as the heat treatment time increased. FT-IR spectroscopic and WAXD data indicated the formation of amide bonds between the amino groups of chitosan and acetic acids carbonyl group, and of interchain hydrogen bonding between the carbonyl groups in the C-6 residues of chitosan and the N-acetyl groups. Our rigorous heat treatment method causes the scaffold to become more susceptible to lysozyme treatment. We performed further examinations of the changes in the biocompatibility of the chitosan scaffold after rigorous heat treatment by measuring the initial cell binding capacity and cell growth rate. Human dermal fibroblasts (HDFs) adhere and spread more effectively to the heat-treated chitosan than to the untreated sample. When the cell growth of the HDFs on the film or the scaffold was analyzed by an MTT assay, we found that rigorous heat treatment stimulated cell growth by 1.5∼1.95-fold relative to that of the untreated chitosan. We conclude that the rigorous dry heat treatment process increases the biocompatibility of the chitosan scaffold by decreasing the degree of deacetylation and by increasing cell attachment and growth.

• Membrane Journal
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• v.6 no.4
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• pp.196-202
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• 1996

In this paper several advantage of RO/NF technologies have been described. However, it should be noted that membrane technology does not solve all the water treatment problems encountered in municipalities. Membranes can provide effective and highly optimized solutions when integrated with conventional technologies such as coagulation, sand filtration, and activated carbon treatments.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.9
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• pp.852-859
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• 2010

Robotic techniques can be one of the promised solutions to address the prostate cancer which is one of the most important public health problems in medical fields. Despite several past and on-going dedicated researches, the systematic techniques and completed theories have not been established well. Therefore we review the state-of-the-art literature on the applications of engineering technologies with particular focus on diagnosis and treatment of prostate cancer. The current status of the elastography and systematic DRE are presented as novel diagnostic tools, and an overview of the applied technologies to address the limits of the treatment (radical prostectomy and brachytherapy) is reviewed.

• Membrane and Water Treatment
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• v.6 no.1
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• pp.77-94
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• 2015

Ultrafiltration membranes have several advantages over conventional drinking-water treatment. However, this technology presents major limitations, such as irreversible fouling and low removal of natural organic matter. Fouling depends heavily on the raw-water quality as well as on the operating conditions of the process, including flux, permeate recovery, pre-treatment, chemical cleaning, and backwashing. Starting with the premise that the optimisation of operating variables can improve membrane performance, different experiments were conducted in a pilot plant located in Granada (Spain). Several combinations of permeate and backwashing flow rates, backwashing frequencies, and aeration flow rates were tested for low-quality water coming from Genil River with the following results: the effluent quality did not depend on the combination of operating conditions chosen; and the membrane was effective for the removal of microorganisms, turbidity and suspended solids but the yields for the removal of dissolved organic carbon were extremely low. In addition, the threshold transmembrane pressure (-0.7 bar) was reached within a few hours and it was difficult to recover due to the low efficiency of the chemical cleanings. Moreover, greater transmembrane pressure due to fouling also increased the energy consumption, and it was not possible to lower it without compromising the permeate recovery. Finally, the intensification of aeration contributed positively to lengthening the operation times but again raised energy consumption. In light of these findings, the feasibility of ultrafiltration as a single treatment is questioned for low-quality influents.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.35-40
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• 2015

Super- and sub-critical water treatments have been of interest as novel methods for protein hydrolysis. In the present study, we studied the effect of sub-critical water (Sub-$H_2O$, $300^{\circ}C$, 80 bar) treatment as well as super-critical water (Super-$H_2O$, $400^{\circ}C$, 280 bar) treatment on the physicochemical properties of porcine skin (PS), which has abundant collagen. Porcine skin was subjected to pre-thermal treatment by immersion in water at $70^{\circ}C$, and then treated with sub- or super-critical water. Physicochemical properties of the hydrolysates, such as molecular weight distribution, free amino acid content, amino acid profile, pH, color, and water content were determined. For the molecular weight distribution analysis, 1 kDa hydrolyzed porcine skin (H-PS) was produced by Super-$H_2O$ or Sub-$H_2O$ treatment. The free amino acid content was 57.18 mM and 30.13 mM after Sub-$H_2O$ and Super-$H_2O$ treatment, respectively. Determination of amino acid profile revealed that the content of Glu (22.5%) and Pro (30%) was higher after Super-$H_2O$ treatment than after Sub-$H_2O$ treatment, whereas the content of Gly (28%) and Ala (13.1%) was higher after Sub-$H_2O$ treatment. Super-$H_2O$ or Sub-$H_2O$ treatment affected the pH of PS, which changed from 7.29 (Raw) to 9.22 (after Sub-$H_2O$ treatment) and 9.49 (after Super-$H_2O$ treatment). Taken together, these results showed that Sub-$H_2O$ treatment was slightly more effective for hydrolysis than Super-$H_2O$ was. However, both Sub-$H_2O$ and Super-$H_2O$ treatments were effective processing methods for hydrolysis of PS collagen in a short time and can be regarded as a green chemistry technology.

• Journal of the Korean Society for Heat Treatment
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• v.14 no.1
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• pp.49-67
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• 2001

• Journal of the Korean Society for Heat Treatment
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• v.14 no.3
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• pp.179-195
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• 2001