본 연구는 딸기 ‘매향’ 품종의 과실을 수확 한 후 LPE 용액에 침지처리 한 뒤 저장기간 동안 당도, 색도, 경도 및 생체중 변화를 조사하여 적정 LPE 처리 농도 및 적정 숙도를 구명하고자 실시하였다. 숙도 70%인 과실을 LPE 0(증류수, 대조구), 10, 50, 100mg·L-1 농도에 1분간 침지하거나, 딸기 꼭지에서부터 익은 비율로 숙도 0%, 50%, 70%, 100%로 등급화한 후에 LPE 0(증류수, 대조구), 2.5, 5, 10, 25mg·L-1 농도에 1분간 침지한 후 실온(20oC±1)에서 40분간 자연건조 한 뒤 4oC 저장고에 12일간 저장하였다. 저장 기간 동안 생체중, 종경도, 횡경도, 색도 및 당도 변화를 조사하였다. 숙도 70% 과실을 수확 후 LPE 0, 10, 50, 100mg·L-1 농도에 침지 후 저장하며 과실의 생체중을 측정하였을 때 처리 농도별 유의차가 없었다. 종경도는 저장 3일째에는 무처리구와 LPE 10mg·L-1 처리구에서 가장 높았다. 저장 6일째부터 12일까지는 10mg·L-1 처리구에서 가장 높았다. 횡경도는 저장 9일째 10과 50mg·L-1에서 가장 높게 측정되었으나 12일째에는 10mg·L-1 처리구는 무처리구와 차이가 없었고 50과 100mg·L-1에서 가장 낮았다. 색차계 L*과 b* 값은 LPE 처리 농도별 저장 기간 별 유의차가 없었고, a* 값은 저장 12일째에 LPE 10mg·L-1 처리를 포함한 모든 농도에서 무처리구에 비하여 높았다. 숙도 0%, 50%, 70%, 100%로 등급화한 후에 LPE 0( 증류수, 대조구), 2.5, 5, 10, 25 mg·L-1 농도에 침지한 후 저장하였을 때 과실 생체중은 LPE 처리농도별 유의 차가 없었다. 종경도와 횡경도는 LPE 처리농도와 상관 없이 숙도 0% >50%> 70%> 100% 순으로 높았다. LPE 농도 처리에 의한 영향은 종경도는 숙도 70% 과실의 경우 저장 3, 6, 12일째 모두 LPE 5mg·L-1에서 가장 높았고 12일째는 LPE 처리구 모두 무처리구에 비해 높았다. 숙도 100% 과실의 경우 저장 12일째에 LPE 10mg·L-1에서 종경도가 무처리구에 비해 높았지만 25mg·L-1에서는 종경도 및 횡경도 모두 가장 낮았다. 색차계 L, b 값은 LPE 처리와 관계없이 숙도 0% > 50% > 70% > 100% 순으로 높아 숙도에 따라 유의차가 있었다. 숙도100%에서 가장 낮은 L*과 b*값이 측정 되었다. 숙도 50%와 70% 과실의 경우 저장기간 중 다른 처리구에 비해 5mg·L-1에서 L*, b* 값이 가장 높았다. 숙도 100%의 경우 25mg·L-1에서는 가장 낮은 값을 보여 과숙이 유발된 것으로 판단된다. 색차계 a* 값은 L*과 b*와는 반대로 그 값의 증가는 숙도가 높음을 의미하는 것으로 숙도 0, 50, 70, 100% 모두에서 LPE 처리 효과를 구분할 수 없었고, 당도는 처리별, 기간별 유의차가 없었다. 결론적으로, LPE는 저장 중인 딸기 과실의 생체중에 영향을 주지 않으면서 경도 및 색도 변화에는 영향을 주는 것을 알 수 있다. 숙도 70% 과실은 타 숙도에 비해 저장성 증대효과가 크며, 숙도 70%일 때 처리농도 LPE 5mg·L-1에서 저장성 증대에 효과적 이였다.

본 연구는 겨울철 제설제 (CaCl2) 농도처리에 따른 맥문동(Liriope platyphylla)과 수호초(Pachysandra terminalis)의 내염성을 평가하고자 수행하였다. 국내에서 제설제로 가장 많이 사용하는 염화칼슘을 각각 0%(Control), 0.5%, 1.0%, 3.0%, 5.0%로 처리한 실험구에 2015년 11월에 맥문동과 수호초를 정식한 후, 이듬해 이른 봄인 2016년 3월에 내염성을 평가하기 위해 초장, 엽장, 엽폭, 엽형지수, 생체중, 건물중, 엽록소함량, 광합성률, 기공전도도, 증산율 등을 측정하였다. 초장, 엽장, 엽폭, 엽형지수, 생체중, 건물중, 엽록소함량, 광합성률, 기공전도도, 증산율 등은 제설제 처리농도가 높을수 록 감소되는 것은 두 식물이 동일하였으나, 맥문동이 수호초보다 좀 더 안정된 생육 및 생리적 특징을 보였다. 무엇보다, 맥문동은 3.0% 이상에서, 수호초는 1.0% 이상의 농도처리에서 생존이 불가능해 맥문동이 수호초보다 내염성이 높은 것으로 판단되었으며, 도시 내 제설제 피해지역에 활용이 가능할 것으로 기대된다.

Magnetite particles were synthesized by co-precipitation of water-soluble 밀 스케일-derived precursor by various concentrations of (0.5, 0.67, 1, 2 N) NaOH and (0.6, 0.8, 1.2, 2.4 N) NH4OH. It is theoretically known that as the concentration of the alkaline additive used in iron oxide synthesis increases, the particle size distribution of that iron oxide decreases. This trend was observed in both kind of alkaline additive used, NaOH and NH4OH. In addition, the magnetite synthesized in NaOH showed a relatively smaller particle size distribution than magnetite synthesized in NH4OH. Crystalline phase of the synthesized magnetite were determined by X-ray diffraction spectroscopy(XRD). The particles were then used as an adsorbent for phosphate(P) removal. Phosphorus adsorption was found to be more efficient in NaOH-based synthesized magnetite than the NH4OH-based magnetite.

The purposes of this study are to develop a chitosan suspension for the carbon dioxide (CO2) concentration indication of packaged food and to investigate the changes in the CO2 indication corresponding to 2-amino-2-methylpropan- 1-ol (AMP) or 2-aminoethanol (monoethanolamine, MEA) addition. Chitosan suspension was prepared by adding chitosan (0.1, 0.2, and 0.4%) to distilled water and subsequently the pH of the suspension was adjusted to 7.0 after the addition of AMP or MEA. Changes in the pH and the turbidity of the chitosan suspension were measured over time under exposure in a normal atmosphere or 100% carbon dioxide environment. The pH of the chitosan suspension exposed at 100% carbon dioxide environment decreased rapidly up to approximately 6.3 in the initial CO2 exposure. The transmittance values of 0.1 and 0.2% chitosan suspensions with 5% AMP increased from 32 to 99% and from 19 to 86%, respectively. The addition of 5% AMP improved the visual indication performance of the chitosan suspension since it increased significantly the width of the transmittance value before and after CO2 exposure. The chitosan suspension with AMP has a potential to be used as a quality indicator of the packaged foods which produce carbon dioxide during storage and distribution.

당뇨병 환자의 혈당을 측정하기 위해 새로운 형태의 페녹시-메틸아미노 포스파젠 진단막을 제조하였다. 먼저 측 정 환경이 혈당 측정에 미치는 영향을 조사하였다. 활성화된 진단막을 가지고 5, 15, 25, 35, 45°C 그리고 상대습도 20%에서 80%까지 변화시키면서 시간에 따른 680 nm에서의 흡광도 변화량(K/S)를 측정하였다. 높은 측정온도와 습도에서도 K/S와 글 루코우즈 농도와의 기울기 값(Dose-Response Slope : DRS)은 크게 영향을 받지 않았다. 두 번째로, 제조된 진단막을 여러 환 경에서 보관한 후, 보관 환경이 글루코우즈의 농도 측정에 미치는 영향을 조사하였다. 새로운 포스파젠 진단막을 50°C에서 8 주 보관한 후 측정한 결과, 보관시간과 온도가 크게 영향을 주지 않았다. 또 상대습도 80%에서도 새로운 포스파젠 진단막의 안정성이 확인되었다.

This study was conducted to investigate the influence of moisture removal using a moisture condensation tube on the odor concentration, when sampling a malodorous substance from an odor discharge facility’s emission sites. For high-temperature and humid gas streams, the odor concentration was decreased through the use of a moisture condensation tube. The multiple odor concentration of the high-temperature and humid gas streams emitted from boiler-burning equipment decreased from a 3,000 to a 1,221 dilution factor when using one or two moisture condensation tube. This multiple odor concentration was further decreased to a 1,000 dilution factor by using two moisture condensation tubes and glass beads, and also was decreased to a 374 dilution factor by using two moisture condensation tubes and silicagel. Among the designated offensive odorous substances, ammonia, trimethylamine and acetaldehyde that have high solubility in water showed high reduction rate of their concentration. Compared to the result using a sampling tube only, the concentration was decreased by 94.8% ~ 97.7% for ammonia, by 87.5% ~ 95.9% for trimethylamine and by 100% for acetaldehyde. The findings of this study indicate that sampling using a moisture condensation tube affects the concentration of multiple odors. Therefore, it is considered that using a sampling tube only for emissions sampling enhances analytical accuracy and precision rather than using moisture condensation tube with sampling tube, even for the emissions containing moisture.

The objective of this study is to investigate indoor radon concentrations and identify influencing factors for one of the representative house type in South Korea. We surveyed 3,000 detached houses using alpha track (raduet) between November 2013 and March 2014. The Arithmetic mean radon concentration of the houses studied was 147.9 Bq/m3 (GM=106.4 Bq/m3), and the range was 11.8 to 1,936.6 Bq/m3. The Arithmetic mean radon concentration in living rooms was 134.2 Bq/m3 (GM=98.8 Bq/m3), much higher value compar with the Arithmetic mean radon concentration in bedrooms (153.0 Bq/m3). The year of constructon, basement status, ventilation frequency and heating period in a house were identified as major factors influencing indoor radon concentrations. The indoor radon concentrations in houses that were constructed prior to 1990 and that had basements were higher than those in the comparison groups. On the other hand, houses that were frequently ventilated and had a short heating period showed a tendency toward lower indoor radon concentration.

일반적인 MBR공법의 경우 허용한계 이상의 고농도 MLSS에서 운영되면 막오염이 급격히 발생된다. 이는 슬러지 케익 축적이 원인이며 이로 인해 분리막 회복을 위한 빈번한 세정이 적용되어야 하고 그 결과 운영비 증가 및 분리막 수 명이 단축된다. 본 연구에서는 (주)에코니티의 자유말단형(End-Free) 분리막을 이용한 MBR 시스템 운전을 진행하였다. 분리막 모듈의 구조적인 특성으로 슬러지가 쉽게 탈리되어 케익의 축적이 발생하지 않아 고농도 MLSS에서도 적용가능함을 확인 하였다. 이에 따라 운전 플럭스를 상향시킬 수 있었고 장기 운전을 통하여 막여과 시스템의 안정운영을 평가하였다.

Single-staged anaerobic fluidized ceramic membrane bioreactor (AFCMBR) was operated at 25oC for the treatment of low-strength synthetic wastewater with chemical oxygen demand averaging 260 mg/L. Tubular ceramic membrane consisting of aluminun dioxide (Al2O3) with 0.5 μm pore size was used. Overall COD removal was achieved as 87-95% with effluent COD concentration of 15-30 mg/L at hydraulic retention time (HRT) ranging from 1 to 3 hr depending upon permeate flux. Maintenance cleaning with NaOCl solution improved GAC scouring to reduce biofouling effectively, which allowed TMP less than 0.15 bar at 20 L/m2.hr. Energy required to operate the AFCMBR was reduced to 0.038 Kwh/m3 at 17 L/m2.hr, which was about 17% of the electrical energy converted by methane produced by AFCMBR.

Phosphorus (P) removal by aluminum sulfate solution was investigated with varying pH and initial P concentrations. P removal was the highest at around pH 6. The pH range where P removal occurred was slightly wider at higher initial P concentrations. Compared to theoretical calculations, it was confirmed that AlPO4 precipitation was the main reason for P removal at low pH. At high pH, where there should be no AlPO4 precipitates, the P removal by adsorption of amorphous Al(OH)3 precipitates was experimentally observed. The P removal by adding amorphous Al(OH)3 precipitates prepared before the adsorption experiments, however, was lower than that by injecting aluminum sulfate solution because the prepared precipitates became larger, leading to less specific surface area available for adsorption. Ions other than sulfate had little influence on P removal.

저장해충 방제를 위하여 환경오염 및 인축의 독성문제 등으로 살충제나 훈증제 등과 같은 농약의 사용이 엄격히 규제되고 있는 상황에서 이러한 문제를 해결하기 위한 대안적 방법으로 이산화염소의 적용을 검토하였다. 이산화염소는 산화력을 가지고 있어서 미생물과 곤충에 대한 살균, 살충력이 있다고 알려져 있다. 본 연구는 주요 저장해충인 화랑곡나방에 대한 저농도 이산화염소의 발육억제 효과를 조사하였다. 화랑곡나방의 알, 2령, 3령, 4령 유충에 아치사량인 50ppm의 이산화염소가 스를 24시간 처리하였을 경우, 번데기까지의 발육기간이 무처리구와 비교하여 알에서는 차이가 없었으나 2, 3, 4령 유충에서는 유의한 차이를 보였으며, 용화율은 알, 2, 3령에서 4령에 비하여 유의하게 낮게 조사되었다. 또한, 화랑곡나방 3령 유충에 50ppm의 이산화염소가스를 0, 6, 12, 24, 48시간 처리하였을 경우, 3령 유충에서 번데기까지의 발육기간은 0, 6, 12시간 처리에서는 차이를 보이지 않았으나, 24와 48시간 처리에서는 발육기간이 유의하게 길어지는 현상이 나타났으며, 용화율 또한 24와 48시간 처리에서 다른 처리시간들에 비하여 유의하게 낮게 나타났다. 이러한 결과는 저농도의 이산화염소가 화랑곡나방의 발육에 영향을 미치는 유약호르몬 가수분해효소(JHE)의 활성에 영향을 준 결과로 추측되며, 이러한 작용기작을 밝히기 위하여 연구가 계속 진행되고 있다.

대기 중 이산화탄소 (이하 CO2) 농도 증가가 왕담배나방(Helicoverpa armiger)의 성페로몬 인식과 합성에 미치는 영향을 조사하였다. 성페로몬 유인제에 대한 왕담배나방 수컷 성충에 대한 풍동실험과 전기촉각전도법(EAG) 실험 결과, 대기 중 CO2 농도가 증가하면 곤충 안테나의 페로몬 감각기에 영향을 미쳐 페로몬성분에 대한 페로몬 감각기의 반응이 감소하였고, 행동반응은 1,000 ppm에서 유의하게 감소하였다. 암컷의 성페로몬 생산은 오히려 CO2 농도가 증가하면 더 많이 생산되었다. 이 두 가지 현상, 수컷의 페로몬 인식과 암컷의 페로몬 생산, 의 상호작용에 의해 교미율은 600 ppm에서 가장 높아졌다가 1,000 ppm에서 감소하였다. 대기 중 CO2 농도에 따른 성페로몬 인식과 생산의 변화는 머리에 있는 CO2 감각기와 관련된 것으로 여겨진다. 성페로몬 인식과정에서 CO2 감각기는 페로몬 감각기로부터 온 페로몬 신호의 해석과 관련된 것으로 보인다. 실제로 CO2 감각기가 제거된 수컷 성충은 정상 수컷보다 성페로몬 루어에 대한 유인 행동이 유의하게 감소하였다.

Soil salinity at newly reclaimed land in west coast of Korea is highly variable and depending on soil characteristics and weather conditions. The objective of this study was to evaluate the spatiotemporal distribution characteristics changes on soil electrical conductivity and exchangeable sodium percentage in Saemangeum newly reclaimed land. Experimental sites was selected at Gyehwa (35o75'N, 126o60'E) in Saemangeum reclaimed land and their dominant soil series was Munpo (coarseloamy, mixed, non-acid, mesic, typic Fluvaquents). Soil samples were periodically collected at 0 ~ 20 cm and 20 ~ 40 cm layer from each site. Soil electrical conductivity had a wide range from 0.15 to 41.76 dS/m, which was variable according to the weather conditions. The average soil electrical conductivity from March 2014 to 2015 was 6.4 and 3.4 dS/m at Gyehwa in Seamangeum reclaimed land. Calcium concentration in soil solution was negatively correlated with soil electrical conductivity and soluble sodium. Soluble sodium concentration had great variations and it was the most influencing single factor for temporal variations of soil electrical conductivity regardless of soil textural properties. The characteristics of Saemangeum reclaimed land had different shares of saline and sodic properties during the experimental period. Our results indicate that persistent monitoring and modeling on soil salinity at coastal tide land is fundamental and the results can provide some useful information for deciding management plans for diverse utilization or to reduce salt damage for stable crop production at reclaimed tidal land.

The concentration of VOCs, NO2 was measured both inside and outside residential homes surrounding an industrial complex. Measurements were performed in the area of the industrial complexes and around 10 km away from the industrial complex area. Benzene did not exceed the air quality standard value. Toluene exhibited a high value of concentration in outdoor Yeosu investigated group. The concentration of NO2 is higher than outside concentrations of houses in both inside housing research group compared with the group of Gwangyang and Yeosu. Benzene and toluene showed high correlation (p<0.001) in the housing interior in Gwangyang, It showed a high correlation (p<0.01) in the housing interior in the comparison group. In Yeosu there was a high correlation (p<0.001) between the inside and outside of the housing in the survey group. In the control group there was only high correlation (p<0.05) in the inside of the housing.

This study was performed as the preliminary research to calculate the concentration of radon exposure and the annual effective dose in public hot spring bath-house. The research found that public bathhouses are the primary cause of the indoor air radon concentration inside a hot spring bathhouse. The indoor radon concentration inside a bathhouse differs significantly by region and among bathhouses in the same region, indicating that the indoor air radon concentration is affected by many factors. The annual effective indoor radon dose by exposure is estimated to range from 1.2×10−2mSv/y to 2.5×10−2mSv/y. Since this research is considered as preliminary research, further and additional relevant research to more reliably calculate the result are necessary, including accumulative research for indoor radon concentrations, and research for exposure coefficients such as the behavior patterns of public bathhouse users, etc.

This paper presents the applicability of natural zeolite (Clinoptilolite) for recovery of ammonium nitrogen from high-strength wastewater stream. Isotherm experiments showed the ammonium exchange Clinoptilolite followed Freundlich isotherm and its maximum exchange capacity was 18.13 mg NH4+-N/g zeolite. The X-ray photoelectron spectroscopy (XPS) analysis indicated that a significant amount of nitrogen was adsorbed to the Clinoptilolite. Optimal flowrate for recovery of high concentration ammonium nitrogen was determined at 16 BV/d (=19.2 L/min) throughout the lab-scale column studies operated under various flowrate conditions. This study also provided a method to determine the recovery rate of final product of nitrogen fertilizer based on the model application to the lab-scale continuous data.

BaMoO4:Tb3+ phosphor powders were synthesized with different concentrations of Tb3+ ions using the solid-state reaction method. XRD patterns showed that all the phosphors, irrespective of the concentration of Tb3+ ions, had tetragonal systems with two main (112) and (004) diffraction peaks. The excitation spectra of the Tb3+-doped BaMoO4 phosphors consisted of an intense broad band centered at 290 nm in the range of 230-330 nm and two weak bands. The former broad band corresponded to the 4f8 →4f75d1 transition of Tb3+ ions; the latter two weak bands were ascribed to the 7F2→ 5D3 (471 nm) and 7F6→ 5D4 (492 nm) transitions of Tb3+. The main emission band, when excited at 290 nm, showed a strong green band at 550 nm arising from the 5D4→ 7F5 transition of Tb3+ ions. As the concentration of Tb3+ increased from 1 to 10 mol%, the intensities of all the emission lines gradually increased, approached maxima at 10 mol% of Tb3+ ions, and then showed a decreasing tendency with further increase in the Tb3+ ions due to the concentration quenching effect. The critical distance between neighboring Tb3+ ions for concentration quenching was calculated and found to be 12.3 Å, which indicates that dipoledipole interaction was the main mechanism for the concentration quenching of the 5D4→ 7F5 transition of Tb3+ in the BaMoO4:Tb3+ phosphors.