• Proceedings of the Korean Magnestics Society Conference
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• 2014.11a
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• pp.50-50
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• 2014

• Advances in nano research
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• v.10 no.1
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• pp.77-90
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• 2021

In the present study, novel chitosan coated magnetic magnetite (Fe3O4) nanoparticles were successfully biosynthesized from mushroom, Agaricus campestris, extract. The obtained bio-nanocomposite material was used to investigate ultra-fast and highly efficient for removal of Ni2+ ions in a fixed-bed column. Chitosan was treated as polyelectrolyte complex with Fe3O4 nanoparticles and a Fungal Bio-Nanocomposite Material (FBNM) was derived. The FBNM was characterized by using X-Ray Diffractometer (XRD), Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Fourier Transform Infrared spectra (FTIR) and Thermogravimetric Analysis (TGA) techniques and under varied experimental conditions. The influence of some important operating conditions including pH, flow rate and initial Ni2+ concentration on the uptake of Ni2+ solution was also optimized using a synthetic water sample. A Central Composite Design (CCD) combined with Response Surface Modeling (RSM) was carried out to maximize Ni2+ removal using FBNM for adsorption process. A regression model was derived using CCD to predict the responses and analysis of variance (ANOVA) and lack of fit test was used to check model adequacy. It was observed that the quadratic model, which was controlled and proposed, was originated from experimental design data. The FBNM maximum adsorption capacity was determined as 59.8 mg g-1. Finally, developed method was applied to soft drinks to determine Ni2+ levels. Reusability of FBNM was tested, and the adsorption and desorption capacities were not affected after eight cycles. The paper suggests that the FBNM is a promising recyclable nanoadsorbent for the removal of Ni2+ from various soft drinks.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.670-678
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• 2004

In oriental medicine, meridian is pathway of bio-energy, and basic an object of diagnosis/therapy. But, in western medicine, meridian has been accepted as action pathway of nerve-endocrine-immune system. Acupuncture effect has been regarded as not effect by transmission of bio-energy but action or response by stimulation. In this paper, when an acupuncturist's bio-energy is passed on(non-insulation) and when is not(insulation), we analysed electric potential on meridian/non-meridian to verify effect of acupuncture therapy. In the results, when bio-energy isn't passed on, bio-potential is reacted to only the first of 4 times acupuncture operating. But when bio-energy is passed on, it is reacted to 4 times, and potential on meridian is higher than that of on non-meridian. Electric potential for same acupuncture operating is different on non/meridians, which implies that physiological construction and bio-energy transmission material is different respectively. When is extracting acupuncture method, potential is higher than that of injection one. It implies that extracting method is more effect than injecting one, in aspect of acupuncture therapy effect. Therefore, acupuncture therapy effect is verified as effect of response by acupuncturist's bio-energy transmission rather than that by only acupuncture stimulus.

• Journal of Korean Society on Water Environment
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• v.37 no.5
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• pp.363-368
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• 2021

On the assessment results of the non-point source pollutant removability of bio-block using waste sewage sludge, at the reactor's initial operation stage, the removal efficiency of COD was slightly unstable. However, after the reactor was stabilized, the COD removal efficiency was higher in the reactor filled with bio-blocks compared to the reactor filled with broken stones. In terms of nitrogen and phosphorus, their removal efficiency was unstable at the initial stage of the reactor operation. This phenomenon was investigated through the bio-block elution experiments. Results indicated that nitrogen and phosphorus were eluted from the bio-blocks affecting their removal at the initial operation. Furthermore, based on elution tests conducted after the dry ashing of the waste sewage sludge, part of the nitrogen and phosphorus was eluted similar to the bio-block elution test results, although considerable amounts of nitrogen and phosphorus were reduced compared to the sludge cake. Prior to the use of the waste sewage sludge bio-blocks as a filter medium to remove non-point source pollutants, a stabilization period of 10 days was required. After the stabilization process, results showed similar characteristics as general aggregates. Moreover, to use the bio-block as a filter medium for the non-point pollutant removal, the filling ratio of 75% was the most suitable as it resulted in the highest nitrogen removal efficiency after the stabilization. The results of this study suggested that waste sewage sludge can be suitably recycled as a mixed raw material for the bio-blocks, with satisfactory application as a filter medium in artificial wetlands, stormwater runoff problems, stream water pollutants to eliminate non-point source pollutants.

• BMB Reports
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• v.43 no.2
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• pp.133-139
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• 2010

We have performed analyses using ancient DNA extracted from 25 excavated human bones, estimating around the 1st century B.C. Ancient human bones were obtained from Nukdo Island, which is located off of the Korean peninsula of East Asia. We made concerted efforts to extract ancient DNA of high quality and to obtain reproducible PCR products, as this was a primary consideration for this extensive kind of undertaking. We performed PCR amplifications for several regions of the mitochondrial DNA, and could determine mitochondrial haplogroups for 21 ancient DNA samples. Genetic information from mitochondrial DNA belonged to super-haplogroup M, haplogroup D or its sub-haplogroups (D4 or D4b), which are distinctively found in East Asians, including Koreans or Japanese. The dendrogram and principal component analysis based on haplogroup frequencies revealed that the Nukdo population was close to those of the East Asians and clearly distinguished from populations shown in the other regions. Considering that Nukdo is geologically isolated in the southern part of the Korean peninsula and is a site of commercial importance with neighboring countries, these results may reflect genetic continuity for the habitation and migration of ethnic groups who had lived in a particular area in the past. Therefore, we suggest that phylogenetic analyses of ancient DNA have significant advantages for clarifying the origins and migrations of ethnic groups, or human races.

• Journal of Nutrition and Health
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• v.39 no.5
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• pp.444-450
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• 2006

In this study, we investigated antimicrobial and cytotoxicity effects to each· fraction extracted from Hizikiafusifonnis (HF), which were extracted methanol (HFM) and then the extract was fractionated into four different types: hexane (HFMH) , methanol (HFMM) , bulanol (HFMB) and aquous (HFMA) partition layers. We determined the cytotoxic effect of these layers on human cancer cells by MIT assay. Among various partition layers of HF, the HFMB and HFMM were showed the strong cytotoxic effects on cancer cell lines we used. The quinone reductase (QR) induced activity of the HFMB on HcpG2 cells at $150\;{\mu}g/mL$ concentration was 2.63 times more effective compared to the control value of 1.0. Although further studies are needed, the present work suggests that HF maybe a chemopreventive agent for the treatment of human cancer cells.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.6
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• pp.61-65
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• 2014

Construction heat insulating material for construction is used in large amounts in industry. In the manufacturing process of this insulation material, a thermal insulation material is completed while a polymer in a liquid state passes through Hall breaker. At this time, the quality and form of a product are determined by a hole in the breaker according to the oil pressure of the fluid and the change of the flow velocity. The friction wear action with regard to partner movement between the two levels of quality of materials affects the performance and the lifetimes of machine parts. In this study of a friction test, SM45C, which is a material used to create brake holes, was used. PVC was used to create the specimen. Moreover, an experiment divided a lubricous state and an unlubricated condition. The resulting value over the load of a pin, the revolving speed of a disk, and the standby state of an experimental result disk could be acquired.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.4
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• pp.185-192
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• 2016

Low operational cost and high efficiency is absolute requirements in the mass production of the ship engine. Increasing the performance of the fuel injection system in the diesel engine is one kind of solution to improve the efficiency. Modern diesel engines are using electronic control module as the main controller in the fuel injection control system, however the mechanical system still involved in the modern control system. In modern ship engine, a control valve was used in injection fuel to regulate the flow of the fuel. High pressure and friction are intensively occur within this part, therefore high wear resist and low friction coefficient material including fine lubricating are needed. This study is to figure out the wear resist material and proper lubricant in the control valve fuel injection. The experiment has been tested using pin on disk in several treatments those are used various lubricants and non-lubricant condition. Two kinds of lubricant were used in this experiment such as INDERIN AW-32 and paraffin oil. INDERIN AW-32 has a better result compared to non-lubricant condition, which are 20% performance increases than non-lubricant condition. SCM 440 was providing small friction coefficient in the lower velocity. The friction coefficient was constantly maintains at 0.1 m/s of velocity or above respectively with the increment of the loads. Using INDERIN AW-32 and paraffin oil the lowest friction coefficient occurred at the lower load, and increases side by side with the increment of loads.

• Journal of the Korean Wood Science and Technology
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• v.44 no.6
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• pp.852-863
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• 2016

Wood-plastic composite (WPC) is a promising and sustainable material, and refers to a combination of wood and plastic along with some binding (adhesive) materials. In comparison to pure wood material, WPCs are in general have advantages of being cost effective, high durability, moisture resistance, and microbial resistance. The properties of WPCs come directly from the concentration of different components in composite; such as wood flour concentration directly affect mechanical and physical properties of WPCs. In this study, wood powder concentration in WPC was determined by Fourier transform near-infrared (FT-NIR) and Fourier transform infrared (FT-IR) spectroscopy. The reflectance spectra from WPC in both powdered and tableted form with five different concentrations of wood powder were collected and preprocessed to remove noise caused by several factors. To correlate the collected spectra with wood powder concentration, multivariate calibration method of partial least squares (PLS) was applied. During validation with an independent set of samples, good correlations with reference values were demonstrated for both FT-NIR and FT-IR data sets. In addition, high coefficient of determination (${R^2}_p$) and lower standard error of prediction (SEP) was yielded for tableted WPC than powdered WPC. The combination of FT-NIR and FT-IR spectral region was also studied. The results presented here showed that the use of both zones improved the determination accuracy for powdered WPC; however, no improvement in prediction result was achieved for tableted WPCs. The results obtained suggest that these spectroscopic techniques are a useful tool for fast and nondestructive determination of wood concentration in WPCs and have potential to replace conventional methods.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.6
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• pp.609-616
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• 2007

Purpose: The aim of the present study was to evaluate the effect of Bio-Oss on bone formation in terms of healing period and type of membrane so that determine the most suitable condition for implant fixation in grafted maxilla. Material & Method: Forty-five biopsy specimens from graft site were evaluated. Sinus lift was performed in the patients with reduced alveolar bone height(less than 5mm). The specimen was taken at the time of implant fixation, which was performed at least 5 months after the sinus lift procedure. All specimens were stained with H&E and Trichrome staining and evaluated histomorphometrically. Result: The results showed that Bio-Oss particle was in direct contact with newly formed bone in all cases. In the present study, the amount of newly formed bone and the residual bone substitute material were not statistically different according to various membrane and different healing period. There was no difference between the histological feature of the specimen of 5 and 31 months. No statistical significance was detected between male and female. Conclusion: The result implies that Bio-Oss does not seem to be resorbed over time regardless of the type of the membranes. The further investigation is needed to clarify this issue with the extended period of follow-up.