In this study, conducted an experiment for fire-resistance of silicone/inorganic flame retardant composites as fire resistant materials. Thermal characteristic analysis were performed by TGA(Thermogravimetric analysis) and Fire-resistance analysis performed by flame test. Through this study, we realized that the silicone/inorganic flame retardant composites have fire resistance and potential as Fire resistant materials.
Land application of biochar (or charcoal) has increasingly been recognized due to its favorable effect as soil amendments. However, depending upon the nature of biomass and pyrolysis condition, biochar may be rich in hazardous inorganic elements. Giant Miscanthus showed its potential as a promising source for biochar manufacture but, the risk of heavy metal leaching from Giant Miscanthus-derived biochar (GMB) has not investigated. The objective of this study was to investigate the heavy metal leachability of GMB manufactured from 3 different temperatures (400, 500, and 700oC). Elemental composition of C, N, H, S, O and 18 metals were analyzed. Leaching concentration of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn was analyzed using 4 different methods (0.1 N HCl, 1 N NH4OAc, toxicity characteristic leaching procedure, and synthetic precipitation leaching procedure). For comparison, same analysis were performed for two char materials, municipal solid waste char (MWC) and sewage sludge char (SSC), manufactured from pilot-scale muncipal waste gasification plant. Elemental composition of GMB complied with the fertilizer guideline whereas the several heavy metal content (Cd, Ni, Pb, and Zn for MWC, Cr, Cu, Ni, and Zn for SSC) was beyond the criteria. From leaching test, concentration of heavy metals from GMB was positively increased with pyrolysis temperature and the acidity of extractant solution. Leaching concentration of plant nutrients (Ca, K, and Mg) was the highest by 1N NH4OAc. Meanwhile, leaching concentration of Cu from MWC and Pb from SSC exceeded the regulatory standard of Korea and US EPA, respectively. In conclusion, with respect to the risk of heavy metals, Giant Miscanthus-derived biochar will be suitable for land application as a soil amendment, while care should be taken for using municipal waste-derived char materials.
The management and control of mineral nutrients is one of most important techniques to increase the productivity and the quality of Korean ginseng. The mineral nutrients are measured with different plant tissues and different growth stages of 2-year-old ginseng grown under hydroponic culture with two different temperatures. The content of N, P, Ca, and Mg were higher at low temperature in both leaves and roots than those at high temperature. However, the content of K was high in leaves at low temperature compared to that of high temperature, while it was not significantly different in roots. The uptake amounts of N and K was higher throughout the experimental period at low temperature in both leaves and roots than those at high temperature. However, the uptake amount of P was not clearly different between two different temperatures and among six different growth stages. The uptake amount of N, P, K was generally decreased in leaves from June to August, while it was increased in roots. The relationship between dry weight and mineral nutrients in leaves was appeared positive with N, K, Ca, and Mg, but negative P. In roots, N, K, Ca, and Mg were negative, showing that was positive with only P. Comparing the correlation coefficients among mineral nutrients in leaves, N and K were significantly positive correlation each other. P was significantly positive correlation with Na and Zn. In case of roots, N was highly significant positive correlation with K, Mg, and Mn, but P was negatively correlated with Ca, Cu, Na, Fe, and Zn.
Farming using natural salts for supply of nutrients to crops is increasing recently. It is necessary to evaluate the salt accumulation in soil and the effects on crop growth by treatment of natural salt. This study was conducted at the organic cultivation fields which garlics were planted. The treatments were no natural salts (control) and plots applied 100~600 kg ha-1 with natural salts. Soil samples were taken from the 0 to 25 cm depth at 12 and 107 day (harvest time) after natural salts application. The results showed that electrical conductivity (EC), exchangeable Na (Exch.-Na+) and Cl- were increased by application of natural salts. But, pH and exchangeable cations (K+, Ca2+ and Mg2+) had not significantly differences among treatments. In 300 kg ha-1 plots of natural salt, the level of EC, Exch.-Na+ and Cl- in top soil (0-5 cm) was were increased more 0.3, 3.7, and 12.7 times than control plot, respectively. EC, Exch.-Na+, and Cl- were highest in the top 5 cm of soil and decreased with depth at 12 days after natural salts application, but were decreased in the plower layer (0-15cm) at the harvest time because they were leached with natural rain. An increasing the application level of natural salt resulted in increasing of sodium adsorption ratio, exchangeable sodium percentage, and percentage of soil dispersion. The concentration of nutrient uptake such as total nitrogen (T-N), chloride (Cl) in garlic had significant difference between control and plots applied with natural salts The content of T-N of garlic in plots with natural salt application was lower than control plot, but Cl is higher than control plot.
The management and the use of major mineral nutriments such as nitrogen, phosphorous, and potassium, etc have been practiced and improved in various cultivating methods of Panax ginseng C. A. Meyer. The purposes of this study were to examine the content of major mineral nutrients on different ginseng aging from 1 to 6 years old, to analyze their uptake and utilization in tissues of ginseng, and to find out their proper managing techniques throughout the cultivation of ginseng. In case of the leaves, the N content was not clearly different from 1 to 6 years old, while the content of P and K was generally decreased throughout the cultivating years. In case of the roots, the content of N and K was gradually decreased from 1 to 6 years old, while the P content was increased until 3 years old, decreased at 4 years old, increased again at 5 years old, and decreased again at 6 years old. The uptake amount of N was increased in root of ginseng from 1 to 6 years old, 0.02 to 2.79kg/10a based on dry weight, respectively. Other minerals of P, K, Ca, and Mg were increased for the cultivating year. Comparing the uptake amounts of N, P, K with different cultivating year, they were the highest uptake amount at 4 years old and then were decreased. The management techniques of major mineral in cultivation of ginseng would be studied and evaluated more in order to have better ginseng production.
사용후 핵연료내 우라늄 및 초우란원소를 회수하는 파이로프로세싱 공정에서 배출되는 금속염화물계 방사성 폐기물은 높은 휘발특성과 붕규산계 유리와의 낮은 상용성으로 인해 고화처리가 쉽지 않은 폐기 물이다. 이를 위해, 본 연구에서는 고화처리의 한 방법으로 탈염화 반응을 통한 고화체제조 개념을 채택 하였다. 솔젤법을 이용하여 탈염화물질, SiO2-Al2O3-P2O5 (SAP)을 합성하였으며 이를 이용하여 탈염화 반 응거동 반응생성물의 고형화 특성을 조사하였다. LiCl계 폐기물과 달리, LiCl-KCl폐기물의 반응은 두 개 의 온도범위에서 반응이 진행되며, 400℃의 경우에는 LiCl이, 약 700℃에서는 KCl이 주로 반응하는 것으 로 확인되었다. 여러 가지 반응실험을 통하여 LiCl-KCl의 탈염화 반응에 가장 적합한 물질은 SAP 1071 (Si/Al/P=1/0.75/1 in molar)인 것으로 확인되었다. 4가지 종류의 고형화 실험을 통하여 고화체의 bulk shape과 densification은 SAP/Salt의 비에 영향 받는 것을 확인하였다. 제조된 고형화 시료는 Product Consistency Test-A법을 이용하여 기본적인 내구성을 평가하였다. 본 연구는 SiO2, Al2O3, P2O5 로 이루 어진 탈염화 물질을 이용하여 반응특성과 고형화 특성에 대한 기본적인 정보를 제공하였으며, 이와 같은 실험을 통하여, 본 연구에서 제안된 탈염화 고화처리방법이 휘발특성이 높고 기존 유리매질과 상용성이 낮은 금속염화물계 폐기물에 적용이 가능함을 확인하였다.
금속염화물계 방사성 폐기물은 전해공정으로 이루어진 파이로프로세싱공정의 주요한 방사성 폐기물이 다. 이와 같은 폐기물은 탄산염이나 질산염과 달리 고온에서 분해되지 않고 바로 휘발되며, 기존의 규산 계 유리와 상용성이 낮아 처리가 쉽지 않다. 본 연구팀은 금속염화물계 폐기물을 고화처리하는 방법으로 탈염화처리법을 채택하였다. 본 연구에서는 그 후속적인 연구로서, 탈염화물질로 제안된 SAP (SiO2- Al2O3-P2O5)의 조성을 변화시켜 LiCl-KCl과의 반응성을 향상시키고 고화공정을 단순화시키고자 하였다. 기본물질계에 Fe2O3를 첨가할 경우 무게반응비 SAP/Salt를 3에서 2.25로 낮출수 있으며, Fe가 Al을 치환 하는 몰분율이 0.1이상이 될 경우에는 오히려 반응성이 점진적으로 감소하는 것으로 확인되었다. 또한 M-SAP에 B2O3를 첨가할 경우에는 유리매질을 사용하지 않고 monolithic form을 제조할 수 있었다. 침출 시험결과 U-SAP 1071이 가장 높은 내구성을 보여주었으며, 1 g의 금속폐기물을 처리시 약 3∼4 g의 고 화체가 발생되며, 이는 기존의 고화처리법보다 약 ⅓∼¼배정도 최종처분부피가 감소되는 효과를 얻을 수 있다. 이상의 실험결과로부터, 기존의 유리고화공정으로 처리가 어려운 휘발성 금속염화물계 폐기물 을 단 하나의 물질을 이용하여 처리할 수 있음을 확인하였으며, 이러한 처리방법은 고화처리시 발생되는 부피를 최소화활 수 있는 대안적인 고화처리방법이 될 것으로 판단된다.
12종 천일염 시료의 성분 분석을 비교한 결과, 식염함량은 국내산 장판염이 85.1%, 국내산 토판염이 89.3%, 수입산 천일염이 91.3%로 나타났다. 국내산 장판염의 불용성분은 0.05%로 가장 낮게 나타났으며 수분함량은 6.4%로 가장 높게 나타났다. 국내산 장판염의 Na 함량은 수입산에 비해 다소 낮게 나타난 반면 Mg, K 함량은 세계적으로 유명한 프랑스 게랑드 소금에 비해 유의적으로 높게 나타났다. 따라서 우리는 인체에 꼭 필요한 무
This experiment was carried out in order to collect the basic data on the standardization of the manufacturing process of Rehmannia glutinosa Libosch. var. purpurea Makino drying. By the drying methods of R. glutinosa, the content of water, inorganic components, reducing sugar, catalpol and benzo[α]pyrene were investigated. The water content was 15.6~17.2% when R. glutinosa was dried by cold-warm air moisture absorption drying method (CAMAD) at 60℃ during 6 days. Among of the inorganic components of R. glutinosa the K content was the most followed by P, Na, Ca and Mg. The reducing sugar content of R. glutinosa by the hot air drying method (HAD) was much more than that by the CAMAD. The catalpol content of R. glutinosa was not different by the drying temperature when it was dried by the CAMAD. The catalpol content of the large size tuber (about 50.0 g/unit) showed a tendency to increase from 60℃ until 70℃ drying temperature, but that of the small size tuber(about 4.0 g/unit) was decreased as being a trend as the drying temperature high when R. glutinosa was dried by the HAD, But the catalpol content R. glutinosa had a tendency to drop significantly at drying temperature above 80℃. The benzo[α]pyrene content was little detected when R. glutinosa was dried by both the SLD and the CAMAD, and the sampling by the HAD indicated within the scope of 5 μg/kg which was the scope to regulate by Korean food and drug administration. In conclusion, it seemed that an appropriate drying temperature of R. glutinosa by the CAMAD and the HAD was about 60℃ and about 70℃, respectively, when we consider the catalpol content and benzo[α]pyrene detection in the manufacturing process of drying R. glutinosa.
우량 나물콩 품종 육성을 위한 자료로 활용하고자 시판 콩나물 및 장려품종 나물콩으로 재배된 콩나물을 사용하여 콩나물의 무기이온 함량과 비타민 함량을 분석하였다. 1. 콩나물의 무기이온 함량은 K, Ca, Mg, Na, Fe, Zn, Mn, Cu의 순으로 많이 함유되어 있었으며, 콩나물을 자엽과 배축으로 분리하여 함량을 분석한 결과 자엽에서의 무기이온 함량은 전체 콩나물과 같은 양상으로 축적되어 있었으나 배축에서는 다른 경향을 나타내었다. 2. 뜨거운 물에 콩나물을 데칠 경우 많은 양의 무기이온이 물로 용출되며 특히 K의 함량 감소가 컸다. 3. 콩나물의 비타민 C 함량은 품종에 따라 변이가 있었으며, 콩나물을 열처리할 경우 비타민 C는 급속하게 감소되었다. 4. 콩나물에서의 비타민 B군(niacine, thiamin, pyridoxin)은 품종별로 함량 차이가 있었으며 대부분 자엽부위에 축적되어 있었다.
This study was conducted to investigate the effects of germanium (Ge) application types on the nutrient concentrations in soil and leaves and leaf characteristics in a ‘Niitaka’ pear orchard in 2004. Ge application included foliar application, fertigation in soils, trunk injection, and the three-combined application. All Ge treatedplots had lower soil NO₃-N, K, and Ca concentrations than those of control plot. Ge concentrations in Ge treated-soils were approximately 50 times higher than those of the control. Ge applications significantly increased area, dry weight, and specific weight in leaves compared to the control. Control treated-trees had greater K concentrations in leaves than the Ge treated-trees, which was oppositively observed for the leaf Ca; leaf Ca was higher on the Ge treated-trees than control. Leaf Ge concentrations were significantly higher on the Ge treated-trees compared to the control, except for the Ge fertigation. Ge concentrations in fruits were greater on the Ge-treated trees than the control trees.