• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.689-695
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• 1996

In order to prove physiological function of ${\beta}-Glucan$ isolated from barley flour by enzymatic method, in vitro experiments simulating the passive membrane transport of gastrointestinal tract were carried out using dialysis membrane. The yield of ${\beta}-Glucan$ from barley flour was $6.2{\%}$ and its constituents were determined to give $81.6{\%}$ total dietary fiber, $72.9{\%}$ soluble dietary fiber, $8.7{\%}$ insoluble dietary fiber, $8.5{\%}$ moisture, $2.5{\%}$ protein and $7.4{\%}$ ash. The water holding capacity of the ${\beta}-Glucan$ preparation was 6 g water/g dry material. The glucose retardation index after 30 minute dialysis was $13.5{\%}$ in the presence of $3{\%}$ ${\beta}-Glucan$. As the dialysis period became longer, the retarding effect toward glucose absorption decreased and the effect was close to zero after 2 hour dialysis. The bile acid retardation index after 30 minute dialysis was 3, 12 and $18{\%}$ in the presence of 1, 3 and $5{\%}$ ${\beta}-Glucan$, respectively. The effect was higher than the glucose retardation index and decreased as the dialysis time elapsed.

• Journal of The Korean Society of Clinical Toxicology
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• v.8 no.1
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• pp.24-29
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• 2010

Purpose: Neonicotinoid insecticides are widely used as they have been proven by experimental studies to have low toxicity to mammals, including humans. As the use of neonicotioids increases, the number of patients with neonicotinoid poisoning has also increased. We conducted a study to investigate the clinical manifestations of neonicotinid poisoning. Methods: We retrospectively analyzed the patients who ingested neonicotinids and who visited the emergency department located in Korea from March 2002 to February 2010. We reviewed the patients' age, gender, the amount of exposure, the elapsed time to presentation, the treatment and the outcome. According to the poisoning severity score, we divided the patients with a Poisoning severity score (PSS) of 0 or 1 into the mild/moderate toxicity group and the patients with a PSS of 2 or 3 into the severe/fatal toxicity group. Results: A total of 24 patients were analyzed. The most common clinical manifestations of neonicotinoid insecticide toxicity were gastrointestinal symptoms (66.7%) such as nausea, vomiting and abdominal pain and the others are respiratory symptoms (16.7%), cardiovascular symptoms (12.5%), metabolic imbalance (12.5%), renal dysfunction (8.3%), CNS symptoms (8.3%), and asymptomatic (29.2%). Twenty patients (83.3%) showed mild/moderate toxicity and 4 patients (16.7%) showed fatal conditions such as shock and mutiorgan failure. The mortality rate was 4.2%. In these fatal cases, the patients developed respiratory failure, hypotension, altered mentality and renal failure at the acute stage and they deteriorated to a more serious condition. This severe toxicity was caused by decreased renal excretion of neonicotinid metabolite, and this was improved after hemodialysis. Conclusion: Most patients with neonicotinoid poisoning and who showed mild toxicity usually improved after symptomatic treatment. However, some patients showed significant toxicity with respiratory failure and renal function deterioration, and intensive care needed, including mechanical ventilation and hemodialysis.

• Applied Chemistry for Engineering
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• v.19 no.6
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• pp.668-673
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• 2008

The objective of this study is to optimize the leaching conditions of sequential leaching and extracting processes for selective Ni recovery from spent Ni-Mo-based catalyst. The selective Ni recovery process consists of two processes of leaching and extracting process. In this 2-step process, Ni component is dissolved from solid spent Ni-Mo-based catalyst into leaching agent in leaching process and sequentially extracted to Ni complex with an extracting agent in the extracting process. The solutions of nitric acid ($HNO_3$), ammonium carbonate ($(NH_4)_2CO_3$) and sodium carbonate ($Na_2CO_3$) were used as a leaching agent in leaching process and oxalic acid was used as an extracting agent in extracting process. $HNO_3$ solution is the most efficient leaching agent among the various leaching agent. Also, the optimized leaching conditions for the efficient and selective Ni recovery were the leaching temperature of $90^{\circ}C,\;HNO_3$ concentration of 6.25 vol% and elapsed time of 3 h. As a result, Nickel oxalate having the highest yield of 88.7% and purity of 100% was obtained after sequentially leaching and extracting processes under the optimized leaching conditions.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.254-262
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• 2003

In this study, the results of applying cold weather concreting mixed with Accelerator for Freeze Protection(AFP) to full scale structures are presented. Since the determination of W/C and amount of AFP significantly have an effect on strength gain and protection of frost damage in early, a full investigation is needed to determine these values at stage of nux design. The flowability of fresh cold weather concreting with AFP was similar to the same W/C. Lower loss of workability and initial slump flow of concrete using superplasticizer of polycarboxylic ester than that of melamine sulphonate showed that polycarboxylic ester was more effective on elapsed time. Temperature histories of specimens located in insulation boxes at the site was similar to that of structures. Thus, it is cleared that simple adiabatic curing method is effective for evaluating in-place concrete strength than specimens cured by sealing method. The investigation results of development of compressive strength of cold weather concreting included AFP with curing methods by logistic curves indicated that AFP can be effective to gain strength at lower temperature than normal curing temperature. In field testing, vinyl sheets were placed over the concrete sections and AFP enabled concrete to gain $5N/{mm}^2$ to protect frost damage in early ages and specified compressive strength of concrete at 28 days under average temperature of $-2^{\circ}C$ (lowest temperature was $-12^{\circ}C$) during site application.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.721-729
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• 2008

The purpose of this study is to investigate the engineering properties of concrete for the early strength development. As a result of reviewing it by establishing each experimental factor and level, the cement had more excellent quality performance in CHC and HESPC than OPC. This study has shown that the PC series admixture was more excellent in side of elapsed time (aging) and early strength development than PNS series admixture. In addition, there was much difference according to the curing temperature, but the early strength development showed the considerable vulnerability in curing temperature below $12^{\circ}C$. To satisfy the strength requirements of 5 MPa/18 hr this study has shown that it needed the curing temperature over $17^{\circ}C$ to the minimum in OPC, over $14^{\circ}C$ in CHC, and over $11^{\circ}C$ in HESPC. On the other hand, as to the strength properties according to W/C, the less W/C was, the more strength development was excellent. If this study is to be used in construction filed on a basis of this result, this researcher is considered as possible of the economic execution of construction by advancing the early strength and by the reduction of construction cost according to shortening construction duration.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.27-46
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• 1996

The purpose of this study was designed to compare with the effects of 4 different surface active bioceramics on the healing process of alveolar bone defects in dogs. Artificial alveolar bone defects depth 4-6mm, width 3-4mm) were created with # 6 round bur at interproximal areas of maxillary canine, maxillary 2nd premolar, mandibular canine, and mandibular 3rd premolar. porous hydroxyapatite(Interpore $200^R$) , 45S5 bioglass, CJ4/lOC crystalline glass, and JJ crystalline glass were implanted in intrabony defects randomly. Experimental groups were divided into 4 categories according to its implant material. After implantation, all groups were examined postoperatively 4 weeks to 12 weeks. 3 dogs was selected randomly and sacrificed after vascular perfusion with 2.5% glutaraldehyde at every 4 weeks. Tissue blocks with surroundig alveolar bone and soft tissues were removed and immersed in formaldehyde/glutaraldehyde fixative. After 20 weeks decalcification with EDTA and formic acid, sections were made and observed under light microscope and transmission electron microscope. In all experimental groups, the encapsulation of inactive connective tissue was observed around graft particles in 4 weeks. As time elapsed, the thickness of surrounding connective tissue was decreased. Osteoconductive bone growth pattern was seen apparently in all groups. CJ4/lOC crystalline glass showed the most active bone formation until 8 weeks. 45S5 bioglass was, however, the most active in new bone formation at 12 weeks. Though there was difference in resorption rate among grafting materials, the size of graft particles was decreased gradually. 45S5 bioglass was resorbed faster than the others. On the other hand, porous hydroxyapatite was degraded most slowly. Phagocytosed particulate matters was observed in the cytoplasm of multinuclear multinuclear giant cell and macrophage under transmission electron microscope. The results suggested suggested that 45S5 bioglass and CJ4/lOC crystalline glass may have some enhanced reparative potential when compared to porous hydroxapatite in the treatment of periodontal defeds. JJ crystalline glass reguires a further investigation of the safety of its use.

• Journal of Radiation Protection and Research
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• v.24 no.2
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• pp.73-86
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• 1999

The ion-exchange method for the purification of primary coolant has been used broadly in PWR(pressurized water reactor)-type nuclear power plants due to its high decontamination efficiency, simple system, and easy operation. However, its non-selective removal of metal and non-radionuclides shortens its life, resulting in the generation of a large amount of waste ion-exchange resin. In this study, the feasibility of electrodeionization (EDI) was investigated for the purification of primary cooling water using synthetic solutions under various experimental conditions as an alternative method for the ion exchange. The results shows that as the feed flow-rate increased, the removal efficiency increased and the power consumption decreased. The removal rate was observed as a 1000 decontamination factor(DF) at a nearly constant level. For the synthetic solution of 3 ppm TDS (Total Dissolved Solid), the power consumption was 40.3 mWh/L at 2.0 L/min of feed flow rate. The higher removal rate of metal species and lower power consumption were obtained with greater resin volume per diluting compartment. However, the flow rate of the EDI process decreased with the elapsed time because of the hydrodynamic resistivity of resin itself and resin fouling by suspended solids. Thus, the ion-exchange resin was replaced by an ion-conducting spacer in order to overcome the drawback. The system equipped with the ion-conducting spacer resolved the problem of the decreasing flow rate but showed a lower efficiency in terms of the power consumption, the removal rate of metal species and current efficiency. In the repeated batch operation, it was found that the removal efficiency of metal species was stably maintained at DF 1000.

• Journal of the Korean Geosynthetics Society
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• v.10 no.4
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• pp.37-47
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• 2011

This paper describes the stability evaluation of reinforced earth wall with steel framed-facing based on field test. The reinforced earth wall with steel framed-facing is composed of wall facing, reinforcement and backfill soil. The wall facing is assembled by steel frames and the aggregates are filled in that. The reinforcement is steel strip type based on bearing resistance. Field test is conducted to evaluate for two separate sections and the measurement is conducted according to construction elapsed time of structure for earth pressure, horizontal displacement of wall facing and reinforcement strain. The evaluation results show that the measured earth pressure is less than theoretical earth pressure due to dispersion effect of earth pressure by the applied reinforcement. Also, the horizontal displacement of wall facing satisfied a empirical criteria and the measured strain of reinforcement had nearly no effect on stability of structure. Therefore, the reinforced earth wall with steel framed-facing has a structural stability and it can be commonly used in field.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.911-917
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• 2015

The objective of this work focuses on the analysis of injection rate and macroscopic spray behavior characteristics with injection pressures as well as combustion and exhaust emission characteristics with injection timing and injection pressure by using a common rail single-cylinder diesel engine. The injection rate was measured by applying the Bosch method, and macroscopic spray behavior characteristics were analyzed with a constant-volume vessel and a high-speed camera. In addition, combustion and emission characteristics were analyzed in a common-rail single-cylinder diesel engine with precise control of fuel injection timing and pressure. For injection pressures of 30MPa and 50MPa, the injection rate was higher at 50 MPa, and the spray development (penetration) was also higher in the same elapsed time. The peak in-cylinder pressure and rate of heat release showed a tendency to decline as injection timing was delayed, and the peak in-cylinder pressure and rate of heat release were slightly higher for higher injection pressures. Higher injection pressures also reduced the mean effective pressure, while the indicated mean effective pressure and torque increased as injection timing was delayed to TDC. Nitrogen oxides had a peak level at injection timings of $BTDC20^{\circ}$(30MPa) and $BTDC15^{\circ}$(50MPa); carbon monoxide emissions were reduced by delaying injection timing from $BTDC30^{\circ}$.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.291-295
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• 2008

We investigated the differences in characteristics of rodent populations among unburned and two burned forest areas which were fire damaged in 2000 and 1980, Samcheok and Yangyang, Gangwon province, Korea. Apodemus peninsulae, Myodes regulus and Tamias sibiricus were captured in three study areas. Total density of rodents was the least at burned area which was damaged in 2000. Trappabilities of Apodemus peninsulae and Myodes regulus were higher in burned areas than in unburned area. However, trappability of Tamias sibiricus was the highest in unburned area. Changes in forest type and habitat structure due to time elapsed after forest fire might affect density and species composition of rodents. Mean body weight of rodents were the highest in burned area which was damaged in 2000 while the lowest in unburned area. Differences in body weight of rodents would be related with the coverage of understory. Detailed long-term ecological monitoring is needed to elucidate changes in characteristics of rodent populations after forest fire.