• Current Research on Agriculture and Life Sciences
• /
• 제1권
• /
• pp.41-46
• /
• 1983

땅콩 기생선충의 종류(種類) 및 그 방제법(防除法)을 구명(究明)코자 1980년(年)부터 1981년(年)까지 2개년(個年)에 걸쳐 실시(實施)된 결과(結果)를 요약(要約)하면 다음과 같다. 1. 땅콩 기생선충으로는 Aphelenchoides besseyi, Aphelenchus avenae, Criconemoides informis, Helicotylenchus dihystera, Meloidogyne arenaria, Meloidgyne hapla, Psilenchus hilarulus, Pratylenchus minyus, Tylenchus sp. 등(等) 9 종(種)이 동정(同定)되었다. 2. 약제처리(藥劑處理)에 따른 선충의 계절적(季節的) 변화(變化)는 처리(處理) 90일후(日後)에는 밀도(密度)가 낮았다가 170일후(日後)인 수확기(收穫期)에는 다시 증가(增加)되는 경향(傾向)을 나타냈으며 당근뿌리흑선충(Meloidogyne hapla)의 밀도(密度)는 수확기(收穫期)에 있어서도 훈증제(薰蒸劑)인 Telone C-17 처리구(處理區)는 무처리구(無處理區)에 비(比)하여 현저(顯著)히 감소(減少)되었으며 1%의 유의성(有意性)이 인정(認定)되었다. 3 초장(草長), 분기수(分技數), 건물중(建物重)은 Telone C-17 처리구(處理區)가 가장 높았으며 그다음 Mocap 10G, Carbofuran 3 G. 등(等)의 순(順)이었다. 4. 수량(收量)에 있어서는 Telone C-17 처리구(處理區)가 무처리구(無處理區)에 비(比)하여 고령(高靈)에서는 73% 선산(善山)에서는 60%가 증수(增收)되어 가장 효과(效果)가 좋았고 다음이 Mocap 10G. Carbofuran 3G. 등(等)의 순(順)으로 나타났다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제17권6호
• /
• pp.52-58
• /
• 2012

Capillary fringe divides the groundwater and the vadose zone controlling the diffusive mass transfer of contaminants and gases. The thickness of capillary fringe is of great importance for the rate of contaminant mass transfer across the capillary fringe. Application of surface active chemicals including surfactants and alcohol-based products into the subsurface environment changes the surface tension of the aqueous phase, which in turn, affects the thickness of the capillary fringe. In this study, a bench-scale model was used to assess the quantitative relationship between the surface tension and the thickness of the capillary fringe. An anionic surfactant (Sodium dodecylbenzene sulfonate, SDBS) and an aqueous solution of ethanol were used to control the surface tension of the groundwater. It was found that the thickness of the capillary fringe is directly proportional to the surface tension. The air entry pressures measured by the Tempe Pressure Cell at different surface tensions using SDBS (200 mg/L) and ethanol (20%, v/v) solutions were in good agreement with the thicknesses of the capillary fringe measured by the model. A simple method to correct the conventional Brooks-Corey model for estimating the air entry pressure was also presented.

• 한국화재소방학회논문지
• /
• 제22권5호
• /
• pp.48-54
• /
• 2008

전 세계적으로 산불이 빈번히 발생되고 대형화산불이 끊임없이 발생되고 있다. 따라서 산불진화를 보다 효과적으로 신속히 하기위해 산불진화용 소화약제가 사용되고 있다. 산불용 소화약제는 일반적으로 물리적 형태에 따라 분말, 액상, 포(泡), 겔(gel)로 구분되어 사용되고 있다. 우리나라에서는 직접적인 산불진화용 소화약제인 강화액과 포소화약제를 사용하고 있어 본 연구에서는 이러한 소화약제들의 식물독성(종자발아율, 소나무 용기묘 치사율) 및 토양생물 독성(지렁이 급성독성) 등 산림생태에 대한 독성평가를 실시하였다. 그 결과, 강화액 및 포소화약제 모두 영향을 미치는 것으로 나타났으며 특히, 강화액의 경우 모든 독성실험방법에 대해 실험개체 모두 100%의 치사율을 나타내어 독성이 가장 강한 것으로 조사되었다. 따라서 향후, 산불진화용 소화약제에 대한 산림생태환경독성 영향평가 방법과 기준제시가 필요할 것으로 판단된다.

• 한국물환경학회지
• /
• 제28권5호
• /
• pp.754-761
• /
• 2012

Several drinking water treatment plants (DWTPs) produce the bottled tap waters (BTWs) as pilot production and provide them for noncommercial use. In 2008, acetaldehyde and chloral hydrate were detected in some BTWs and the public worry over the safety of the water. In this study, the BTWs produced from 7 DWTPs were tested for 13 chemicals including disinfection byproducts (DBPs). The level of four trihalomethanes (THMs) were increased up to 15 days. The average concentration of them was 0.0075 mg/L at the time of bottling and it was increased to 0.0214 mg/L after 15 days. The average acetaldehyde concentration was 0.0406 mg/L at the time of bottling but it was went up to 0.2251 mg/L after 11 days and then decreased. Although the initial concentrations of DBPs were below the drinking water standard, we also traced them at different storage conditions. Temperature affected the formations of THMs and acetaldehyde concentrations significantly. While the average concentration of THMs ranged from 0.0113 to 0.0182 mg/L at $25^{\circ}C$, it was increased to 0.0132 ~ 0.0256 mg/L at $50^{\circ}C$. In case of acetaldehyde, concentration ranged from 0.0901 to 0.2251 mg/L at $25^{\circ}C$, it was increased to 0.3394 ~ 1.0591 mg/L at $50^{\circ}C$. Throughout the tests with 7 BTWs samples, none of the chemicals was exceeded the drinking water standard of Korea. Therefore, it is recommended to avoid the exposure of BTWs to sunlight or high temperature during distribution and storage.

• 한국지반공학회지:지반
• /
• 제13권6호
• /
• pp.123-138
• /
• 1997

중금속으로 오염된 점성토의 정화에 대한 electrokinetic기술의 효율을 연구하기 위하여 포화 해성점토를 납으로 오염시켜 전기삼투시험을 수행하였다. 이를 위하여 실험조건으로서 납의 오염농도 500, 5,000, 50,000mg/kg, 공급전류 10, 50, 100mA, 가동시간 5, 15, 30일 및 3가지의 효율 향상기법을 적용하였다. 유입수와 유출수의 pH, 전기삼투유량 및 전기전도도를 시험중에 측정하고 또 시험 완료후에 공시체전 길이에 걸쳐 pH및 잔존 납농도를 측정하여 제시하였다. 시험결과에 의해서 electrokinetic 기술이 효과적인 방법이라는 결론을 얻었다. 또한 음극에 침강된 수산화납을 용해시키기위해 초산을 가하게 되면 정화효율이 향상된다는 사실을 알 수 있었다.

• 한국토양비료학회지
• /
• 제51권1호
• /
• pp.28-34
• /
• 2018

Yuzu (Citrus junos) gummosis disease, caused by Phytophthora nicotianae, was first reported in 1997. As known in citrus, Phytophthora is the most fastidious soil-borne pathogen to control. In order to minimize its damage to Citrus spp., integrated pest management (IPM) approach, including fungicide chemicals and resistant cultivars, is necessary. Therefore, in this study we tried to evaluate tolerance of yuzu cultivars and its related species against yuzu Phytophthora. Trifoliate orange was evaluated as a susceptible host to yuzu Phytophthora by both mycelial growth onto extract media and immature fruit inoculation. However, in zoospores spray-inoculation on 2-year-old cuttings tree, trifoliate orange appeared to have a resistant property as showing less than 6% diseased leaf rate. Among yuzu cultivars only 'Namhae No. 1' appeared resistant property against both P. nicotianae and P. citrophthora. The 'Namhae No. 1' showed 5.7% and 10.6% diseased leaf ratio by P. nicotianae and P. citrophthora, respectively. Clearly, in order to reduce damages caused by two yuzu Phytophthora, we suggest that growers may utilize a trifoliate orange as a rootstock and 'Namhae No. 1' as a scion for fruit production.

• Geomechanics and Engineering
• /
• 제15권2호
• /
• pp.729-738
• /
• 2018

Soft clay soils due to their various geotechnical problems, stabilized with different additives. Traditional additives such as cement and lime will not able to increase the soil strength properties significantly. So, it seems necessary to use new additives for increasing strength parameters of soft clay soils significantly. Among the new additives, epoxy resins have excellent physical and mechanical properties, low shrinkage, excellent resistance to chemicals and corrosive materials, etc. So, in this research, epoxy resin used for stabilization of soft clay soils. For comprehensive study, three clay soil samples with different PI and various clay mineral types were studied. A series of uniaxial tests, SEM and XRD analysis conducted on the samples. The results show that using epoxy resin increases the strength parameters such as UCS, elastic modulus and material toughness about 100 to 500 times which the increase was dependent on the type of clay minerals type in the soil. Also, In addition to water conservation, the best efficiency in the weakest and most sensitive soils is the prominent results of stabilization by epoxy resin which can be used in different climatic zones, especially in hot and dry and equatorial climate which will be faced with water scarcity.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2004년도 학술발표회
• /
• pp.90-101
• /
• 2004

The present trend of disposing treated sewage water by allowing it to infiltrate the soil brings a new dimension to environmental problems. It is therefore necessary to identify the chemicals likely to be present in treated sewage water. A soil column experiment was conducted to determine the behavior of chemical species in soil columns applied with secondary treated sewage water. To predict the behavior of chemical species, a multicomponent solute transport model that includes the biochemical redox process and cation exchange process was developed. The model computes changes in concentration over time caused by the processes of advection, dispersion, biochemical reactions and cation exchange reactions. The solute transport model was able to predict the behavior of the different chemical species. The model reproduced the sequential reduction reaction. To design the safe depth of plow layer where $NO_3^-$ is totally reduced, a numerical study of $NO_3^-$ leach was done and it was found out that the pore velocity and concentration of $CH_2O$ at the inject water was found to affect $NO_3^-$ reduction in the mobile pore water phase. It is revealed that the multicomponent solute transport model is useful to design the land treatment system for $NO_3^-$ removal from wastewater.

• 한국토양비료학회지
• /
• 제50권4호
• /
• pp.275-284
• /
• 2017

The food situation in North Korea (Democratic People's Republic of Korea, DPRK) has been in difficulty situation because of a shortage of energy, and of raw materials such as fertilizer and agricultural chemicals. The international agricultural aid programs can alleviate some difficulties in the agricultural areas, but the policies and measures in North Korea can not help difficulties in the agriculture due to the institutional obstacles enforced by DPRK. The arable area of DPRK is approximately $20,000km^2$, of which $14,000km^2$ is well for cereal cultivation. Fertilizer supplies in recent years between 700,000 and 750,000 tons annually were less than 50% of the normal requirement. Also, North Korea strongly needed to inject phosphorus fertilizer and lime to increase the fertility. Soil degradation in DPRK was characterized by physical and chemical changes caused by rapid loss of clay particles and organic matter. Intensive ploughing and tilling to grow crops may lead to massive soil degradation and declining yields. Although farmers in the DPRK have faced numerous challenges, not least of which are soil erosion, scarce inputs and extreme weather like drought, flooding and cold spells. Therefore farmers should be encouraged to adopt more environmentally sound cropping practices, to access quality seeds and planting materials and to reduce losses after the harvest.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제8권2호
• /
• pp.44-54
• /
• 2003

토양 슬러리 시스템에서 유해물질의 미생물 분해시 계면활성제를 고려한 속도론적 모델을 개발하였다. 이 모델은 오염물질과 계면활성제의 분배, 미생물의 수용액상, 미셀상, 흡착상 분해, 계면활성제 첨가에 의한 대상물질 용해, 대상물질의 물질전달을 포함한다. 오염물질은 phenanthrene, 계면활성제는 Triton X-100, Triton NP-10, Igepal CA-720, Brij 30을 적용하였다. 미셀상 분해가 존재할 경우 매우 낮은 미셀상 이용도에서도 전체 분해속도를 크게 향상시킬 수 있었다. 미셀상 이용성이 존재하는 경우와 그렇지 않은 경우 모두 계면활성제 농도가 증가할수록 수용액상 농도가 감소하여 전체 분해속도는 감소하였다. 흡착상 분해는 수용액상 분해나 미셀상 분해와 비교하여 전체 분해속도에 미치는 영향이 적었다. 본 모델은 계면활성제를 이용한 오염토양 생물복원시 계면활성제 탐색과 최적 공정 설계에 활용될 수 있을 것이다.