• Membrane and Water Treatment
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• v.11 no.3
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• pp.223-229
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• 2020

Here magnetic iron oxide particles (MIOPs) were synthesized under atmospheric air and which size was controlled by regulating the flow rate of alkali addition and used for efficient removal of bovine serum albumin (BSA) from water. The MIOPs were characterized using field-emission scanning electron microscopy (FE-SEM), Fourier transformation-Infrared spectroscopy (FT-IR) and vibrating sample magnetometer (VSM). The results revealed a successful preparation of the MIOPs. The removal efficiency for BSA using MIOPs was found to be about 100% at lower concentrations (≥ 10 mg/L). The maximum adsorption of 64.7 mg/g for BSA was achieved as per the Langmuir adsorption model. In addition, microfiltration membrane for removal of BSA as model protein organic foulant is also studied. The effect of various MIOPs adsorbent sizes of 210, 680 and 1130 nm on the absorption capacity of BSA was investigated. Water permeability of the BSA integrated with the smallest size MIOPs membrane was increased by approximately 22% compared by the neat BSA membrane during dead-end filtration. Furthermore, the presence of small size MIOPs were also effective in increasing the permeate flux.

• Fashion & Textile Research Journal
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• v.14 no.6
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• pp.941-951
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• 2012

As smartphones permeate the consumer lifestyle, branded application and mobile shopping have also received increased attention as an important marketing channel. This study identifies the general information about the use of smartphones, attitudes toward fashion applications, and mobile shopping intentions for smartphone users. Focus group interviews were conducted and 22 interviewees participated. The age of the participants ranged from 21 to 45 years old (55% were females). When examining the motivation to adopt a smartphone, respondents presented the comparable characteristics of early adopters and late adopters according to the time of adoption. Most respondents over the age of 30 showed some troubles to use a smartphone; however, participants in their 20s tended to enjoy exploring the new technology. More than half of respondents were aware of fashion applications, but were dissatisfied with fashion apps and used them infrequently. Respondents pointed out that fashion related apps were not too practical because they were not updated regularly, provided only limited information, and focused on brand promotions. In order to increase the intention to adopt mobile shopping, the price and payment security system needs to be considered. This was an exploratory study to identify the possibility of fashion branded apps as a major distribution channel. The findings of this study provide fundamental information to formulate marketing strategies for fashion businesses that have developed fashion apps.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.1
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• pp.38-46
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• 2005

In this research, we tried to combine the coagulation/sedimentation process as pre-treatment with UF membrane filtration to reduce the membrane fouling and to improve the permeate water quality. We used the Jet Mixed Separator (JMS) as coagulation/sedimentation process. We observed that the HPC and E.Coli can't be removed through the direct UF memebrane filtation of surface water. The removal efficiency of dissolved organic substances, indicated by E260 and DOC, was 40% and 15%, respectively. However, the removal efficiency of it increased two time as a result of combination of JMS process as coagulation/sedimentation pre-treatment. This was resulted from the formation of high molecular humic micro-floc through JMS process. The accumulation amount of irreversible cake layer which was not removed by backwashing was less than direct UF membrane filtration of surface water. Moreover, the loading rate of fouling induced substances, such as humic substances and suspended substances, on membrane surface decreased drastically through JMS process. As a result, the accumulation amount of irreversible cake on membrane surface was decreased.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.79-86
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• 2008

In Korea, most of the drinking water treatment relied upon the availability of the surface water, of which the raw water quality varied significantly by season and location. Therefore, the comparison of two operation modes (Pressurized type and Submerged type membrane system) must be estimated before the long-term establishment of two systems. In this study, two pilot-scale microfiltration systems with the capacity of $50m^3/day$ were installed and operated in two different modes, and the applicability of the system was determined based on the results such as the TMP (Trans-Membrane Pressure) and flux. For quantitatively comparing the two systems, a new concept, DRF (Differential Resistance Fraction) was introduced. The accumulated sum of the permeate after each cycle of chemical cleaning was also used as a tool for the system comparison.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.4
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• pp.391-396
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• 2014

Ultrapure water (UPW) is water containing nothing but water molecule ($H_2O$). The use of UPW is increasing in many industries such as the thermal and nuclear power plants, petrochemical plants, and semiconductor manufacturers. In order to produce UPW, several unit processes such as ion exchange, reverse osmosis (RO), ultraviolet (UV) oxidation should be efficiently arranged. In particular, RO process should remove not only ions but also low molecular weight (LMW) organic matters in UPW production system. But, the LMW organic matter removal data of RO membranes provided by manufacturers does not seem to be reasonable because they tested the removal in high concentration conditions like 1,000 ppm of isopropyl alcohol (IPA, MW=60.1). In this study, bench-scale experiments were carried out using 4-inches RO modules. IPA was used as a model LMW organic matter with low concentration conditions less than 1 ppm as total organic carbon (TOC). As a result, the IPA removal data by manufacturers turned out to be trustable because the effect of feed concentration on the IPA removal was negligble while the IPA removal efficiency became higher at higher permeate flux.

• Journal of Pharmaceutical Investigation
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• v.41 no.4
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• pp.233-238
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• 2011

DEET, N,N'-diethyl-m-toluamide, is the most commonly used mosquito repellent. However, it can easily permeate through skin leading to toxic effects. A recent study showed that the ortho analogue of DEET showed enhanced repellency with reduced permeation compared to the commercially used meta analogue. Thus, in order to understand the differences in properties and effectiveness among the m-, o- and p-analogues of DEET, an HPLC-UV method was developed for separately analyzing the three analogues. Moreover, stability profiles at temperatures ranging from $30^{\circ}C$ to $70^{\circ}C$ as well as pH ranging from pH 3 to pH 9 have been determined. All three analogues were stable with no degradation observed during the 5 day period. o-DEET therefore could be further developed into a safer and more effective mosquito repellent.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.383-385
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• 1999

Effects of temperature and initial pH of the medium on production of citric acid from cheese whey permeate by Aspergillus niger were investigated. A. niger was cultivated at four different temperatures (27, 30, 33, $36^{\circ}C$) and four different pHs (2, 3, 4, 5) for 15 days. During the fermentation the concentrations of lactose and citric acid in the culture broth were measured. The maximum production of citric acid which was 33.9 g/l (68.26% yield based on lactose utilized) was obtained at $33^{\circ}C$ and pH 3. The production of citric acid was not much affected by shaking speed. However, the shaking speed was found to influence the form of pellets during cell growth.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.87-93
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• 2014

In this study, the reinforced concrete rahmen bridge damaged by the chloride attack was investigated. According to the investigation, the degraded concretes on cantilever kerb and end part were intensively observed. Thus, the chloride content test and half-cell method were performed to evaluate the degraded parts. As a result, the contents of chloride on degraded parts were C and D grade. On the other hand, the half-cell potential values of rebar in degraded concrete were measured with the minor corrosion. This rebar corrosion is expected to progressing. Chloride content D grade is due to expansion pressure by corrosion of rebar and freeze-thaw by permeate water, could see progresses rapidly degradation. In order to prevent chloride attack to concrete deck caused by deicing salts, corresponding to the chloride critical concentration must maintain grade b or at least grade c. Chloride condition evaluation standard apply to evaluation of marine structure chloride attack with chloride attack by deicing salts.

• Biomedical Science Letters
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• v.8 no.3
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• pp.161-165
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• 2002

Apoptosis can be difficult to detect in routine histological sections. Since extensive DNA fragmentation is an important characteristic of this process, visualization of DNA breaks could greatly facilitate the identification of apoptotic cells. Several techniques for the qualitative and quantitative detection of this process have been established; recently, an in situ nick end-labelling technique based on the detection of DNA fragmentation, which is a molecular characteristic of apoptotic cell death, was described. Applying this method to paraffin sections of rat tissues, sensitivity was observed to be inconsistently low with regard to the expected number of apoptotic cells. I describe a new modified method for formalin-fixed, paraffin-embedded tissue sections, pretense pretreatment to permeate the tissue sections that involves an TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling) is acknowledged as a method of choice in the rapid identification and quantification of the apoptotic cell fraction in paraffin tissue preparations. TUNEL was performed without apoptosis and with apopotosis samples to each of the three concentrations of proteinase K (10, 25, 40 mg/ml) pretreatments. In this study, I show that chemical pretreatments of the tissue sections in proteinase K (25 mg/ml for 15 min at room temperature) considerably enhances the sensitivity of this nick end labelling technique.

• Journal of Pharmaceutical Investigation
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• v.35 no.2
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• pp.71-74
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• 2005

The aim of this study was to analyze characteristics of the barrier function of excised porcine buccal mucosa to the test compounds, estradiol, propranolol HCI, melatonin, and mannitol with a wide range of partition coefficient values. The permeability of melatonin was measured through frozen, stored, and fresh porcine buccal mucosa to examine the impact of storage conditions on the permeability of porcine buccal mucosa. The results demonstrated that the ex vivo permeability of the porcine buccal mucosa was greater for more lipophilic solutes, which was consistent with a series of molecules transported by passive transepithelial diffusion. The melatonin permeation profiles through frozen, stored, and fresh mucosa illustrated that damage was incurred by the freezing process of the mucosal tissue, leading to loss of the barrier function and thereby an increased permeation coefficient. It can be observed that the influence of compound lipophilicity on the association of the compounds with buccal mucosa was clear. The relationship between permeation coefficient and Log P values for the four compounds investigated demonstrated a proportional relationship, further confirming the importance of the lipophilicity of a compound to permeate the buccal mucosa. These results showed that the ex vivo porcine buccal mucosa model is a suitable tool to screen oral mucosal permeability.