Four stream- activated carbons were prepared by carbonizing apricot stones at 600℃ followed by gasification with steam at 950℃ to burn-off's=17, 32, 49 and 65%. The textural parameters of these activated carbons were determined from nitrogen adsorption results at 77 K. The total pore volume and the mean pore radius increased with the increase of % burn-off whereas the surface area increased with the increase of burn- off from 17 to 32 and further to 49%. Further increase of burn-off to 65% was associated with a considerable decrease in surface area as a result of pronounced pore widening due to pore erosion. The surface pH values of the carbons investigated range between 7.1 and 8.2. The adsorption of oxamyl onto the activated carbon followed pseudo-second order kinetics and the equilibrium adsorption isotherms fitted Langmuir adsorption model. The adsorption of oxamyl proved to be of the physical type and took place in non-micropores. The amount of oxamyl adsorbed expressed as qm depends to a large extent to the surface area located in non-micropores S∝ n, where a straight line relationship passing through the origin was obtained.
Activated carbons were prepared by impregnation of crushed clean date pits in concentrated solutions of phosphoric acid or zinc chloride followed by carbonization in absence of air at 600℃. Steam-activated carbon was prepared by gasifying 600℃-carbonization product at 950℃ to a burn-off = 50%. KOH- activated carbon was prepared by impregnating date pitscarbonization product obtained at 450℃ in concentrated KOH solution followed by carbonization at 840℃. Textural properties of these carbons were determined from nitrogen adsorption at -196℃ and the chemistry of the carbon surface was investigated by determination and of the surface carbon-oxygen (C-O) groups using bases of variable strength and dilute HCl. The adsorption of endosulphan at 27℃ on all the carbons prepared was undertaken. Adsorption of this pesticide at 32 and 37℃ was also undertaken for steam-activated and KOH-activated carbons. Phosphoric acid-activated carbons and steamactivated carbons are mainly microporous and have high surface concentration of C-O groups of acidic nature. Steamactivated and KOH-activated carbons exhibited surface areas 〉 1000 m2/g and contain micro and non-micrpores. The adsorption of endosulphan was related to the surface area of non-micropores and was retarded by the high concentration of surface C-O groups. The thermodynamic properties indicated the feasibility of the adsorption process and the possible regeneration of the carbon for further use.
장미의 병해충 방제에 등록되어 있는 34종, 등록되어 있지 않은 5종, 그리고 보조제 3종, 충 42종의 농약에 대한 칠레이리응애(알, 약충, 성충)와 점박이응애(알, 성충)의 선택독성과 칠레이리 응애에 의한 점박이응애 밀도억제효과를 조사하였다. 살비제 중 acequinocyl, bifenazate, fenbutatin oxide, spirodiclofen은 칠레이리응애에 대해서 독성이 낮았으나, 점박이응애에 대해서는 독성이 높았다. 살충제는 acetamiprid, imidacloprid, spinosad, thiamethoxam, acetamiprid+etofenprox가 칠레이리응애와 점박이응애에 대해서 독성이 없거나 적었다. 살균제 중에는 azoxystrobin, kresoximmethyl, myclobutanil, nuarimol, triadimefon, triflumizole, oxadixyl+mancozeb이 칠레이리응애와 점박이응애에 대해서 영향이 없었다. 농약보조제인 cover와 siloxane은 칠레이리응애에 대해서 독성이 컸으나, spreader는 영향이 없었고, 점박이응애에 대해서는 독성이 없거나 낮았다. 장미시설하우스에 서 칠레이리응애에 의한 점박이응애 밀도억제효과를 조사하기 위하여, 점박이응애의 밀도가 잎당 65.3마리였을 때, 칠레이리응애를 주당 30마리 방사하였다. 방사 후 11일에 점박이응애 밀도가 잎당 3.8마리로 크게 감소하였고, 방사 후 20일에는 잎당 0마리로 밀도억제효과가 높게 나타났다. 조사기간 동안 흰가루병 방제로 살균제 4회(kresoxim-methyl, myclobutanil, nuarimol, triflumizole)와 총채벌레 방제약제를 1회(spinosad)처리하였으나, 칠레이리응애 밀도에는 영향이 없었다. 이상의 결과로 보아 장미 병해충의 종합관리체계에서 칠레이리응애에 독성이 적은 약제와 칠레이리응애를 함께 이용할 수 있을 것이다. controllability. Based upon these results, it is recommended that the developing nursing interventions to change causal attribution and self-efficacy is necessary. A number of theoretical relationships and empirical finding are confirmed by this data, and future proposals in research is suggested. 따라서 교사들의 관심유형과 실행수준에 따라 수행평가에 대한 지원을 달리함으로써 교사들의 관심도와 실행수준을 향상시켜야 할 것이며 보다 효과적인 수행평가가 실시되도록 해야 할 것이다.. 결론적으로 현재 우리나라에서는 갈색 정도의 차이 문제이지 갈색란을 좋아함을 알 수 있었고, 교육에 의해 조금씩은 고정 관념을 바꿀 수 있는 가능성을 확인할 수 있었다.ique impact at 0.70 km/s and 0.91 km/s were compared with experimental results and Eulerian hydrocode CTH simulation results. The Lagrangian code NET3D is superior to Eulerian code CTH in the computational accuracy. Agreement with the experimentally obtained final deformed cross-sections of the projectile is excellent. (3) Agreement with the experimental ballistic limit data, particularly at the high-obliquity impacts, is reasonably good. (4) The simulation result
단감원에서의 농약 사용 실태를 2000년(62농가)과 2001년(17농가)에 단감 주산지인 진주, 사천, 창원, 창녕, 김해 등지에서 단감 재배 농가를 대상으로 설문과 방제력 수집을 통하여 조사하였다. 단감원의 년 평균 농약 살포 횟수는 2000년에 7.6회, 2001년에 7.7회였으며, 약제를 살포하는 농가의 비율은 일년 중에서 6월과 7월에 가장 높았다. 살포한 살균, 살충제의 종류는 2000년에는 각각 36종과 34종이었으며 2001년에는 각각 22종과 23종이었다. 최종 약제 살포시기는 9월 중순이 가장 많았다. 단감원에서 많이 사용하고 있는 살균제로는 2000년에는 mancozeb과 thiophanata-methyl, benomyl순이었으며, 2001년에는 lime sulfur와 benomyl, carbendazim순이었다. 살충제는 두 해 모두 deltamethrin, methidathion, fenitrothion순이었다. 사용한 약제가 단감이나 감에 고시되어있는 비율은 품목수 기준으로 50% 내외 이었다.
This study was conducted to investigate the consumers' recognition and information need for food safety, especially focused on pesticide residues, foodborne illness, and food additives. The data were collected from 350 adults living in Taegu and Pusan by the self-administered questionnaire. Frequencies and chi-square tests were conducted by SPSS. The results of the survey were as follows: (1) the consumers' concerns about food safety were high, (2) many respondents worried about eating vegetables, fruits and grains in turn because of pesticide residues, and did not trust the results from food-safety tests, (3) the major factor for foodborne illness was regarded as unfreshed or contaminated food stuffs, (4) many consumers concerned highly about preservatives among food additives, and tried to consume food containing less food additives, and (5) many respondents wanted to get the information about harmfulness of pesticide residues in foods, method to choose fresh food, and safety of food additives.
병해충을 막기 위해 농업용 살충제가 광범위하게 사용되고 있다. 농약사용에 따른 생물학적 위해가 우려되며 농약이 또 다른 환경유해요인과 인체에 상승적으로 작용할 경우 농업재해로 이어질 가능성이 있다. 다양한 인자에 의한 DNA손상을 감지하는데 유용한 단세포 겔 전기영동법을 이용하여 살충제와 방사선에 의한 사람 림프구 DNA손상을 평가하였다. 각기 다른 농도로 살충제를 10분간 전처리한 림프구와 정상 림프구에 0-2.0 Gy의 방사선으로 조사한 다음 DNA
Since 1982, female agricultural workers are populous than male in Korea. Previous study was suggested that female workers are more sensitive to the agricultural medicine poisoning than male. This study was conducted with the aim of evaluating the impact on plasma components and nutrient intakes in female agricultural workers by the use of pesticides. Data were obtained from 44 females residing in Wonjoo, Kangwon-do area. Analysis for the general characteristics, nutrient intakes, and plasma components of the subjects were performed by physical examination, 24-hour recall method and venous blood sampling. They were divided into 3 groups according to the degree of the pesticide use: 8 in none(Non-expose group), 14 in low(〈4/yr)(Low-expose group), and 22 in high(≥4/yr)(High-expose group). The results are summarized as follows. Serum glucose, SGOT, SGPT, triglyceride, HDL-cholesterol did not correlated with pesticide use and were not different among the groups. But serum total cholesterol was higher in pesticide use group. With increasing the number of pesticide use times, leukocyte count was tended to increased. Eighty two percent of the subjects were hemoglobin less than or equal to 12g/dl. Hematocrit, MCV, MCH, MCHC, serum Fe, Serum ferritin belonged to normal range and did not correlated with pesticide use. Intake of energy, Fe, vitamin B2 were lower than RDA. Fe, K, and vitamin A intake were higher in don't use group than the other groups. There are not many differences according to using the pesticide in anthropometric measurements, nutrient intakes, and blood components, except for serum total cholesterol level and some nutrients intake. But these results suggest the need the systemic researches about the effects the pesticide using on nutritional status in Korean agricultural workers.
Microwave-assisted extraction (MAE) is known as a more environmental-friendly process with economic advantages in terms of less time, less solvent, less energy and less waste than the current reflux method that is time-consuming. MAE was applied to extract three pesticides (quintozene, tolclofos-methyl and procymidone) from ginseng in a pesticide residue analysis and eliminate pesticide contaminants from ginseng prior to production of the ginseng extracts. The optimal conditions for pesticide extraction from ginseng were 50% in power (150 watts), 2 minutes, 20 mL hexane and 2.0 g sample. The results of optimal conditions were compared with those of Soxhlet method (7 hours, 150 mL hexane). The recoveries between two methods were almost same while time and amount of solvent used in MAE were significantly decreased in comparing with those in the Soxhlet methods. When the 45% ethyl alcohol as a extraction solvent was applied to eliminate pesticides from ginseng prior to the production of the ginseng extracts, it was found that 100% quintozene, 69% tolclofos-methyl and 83% procymidone were eliminated from ginseng. The data showed that MAE may be used to eliminate pesticide contaminants in ginseng prior to making the ginseng extracts.
Limited information is available on the acceptability of Korean MRLs(maximum residue limits) and the health risk based on the pesticide exposure by food intake. The aim of this study was to evaluate TMDI(theoretical maximum daily intake) and EDI(estimated daily intake) for Korean by using MRLs, food intake, residue data, and correction factors, and compare with ADI(acceptable daily intake) in order to estimate the health risk based on the pesticide exposure. The study was performed in three steps. In the first step, the residual pesticides in each category of food were investigated using the pesticide residue analytical data(1995-96) from officially approved organizations and the analytical data for poultry was adopted from Korean food code method. In the second step, TMDI was estimated from MRLs and food factors, and was compared with ADI. In the third step, the effectiveness of each culinary treatment (washing, peeling, steaming, boiling, and salting) was evaluated and EDI was calculated using pesticide residue data, food factor, and correction factor by treatment. TMDI obtained from MRLs and food intake, and food intake was summed as 1,100.99 g, which was 79.1% of total consumption. The percent ratio of TMDI to ADI for 156 pesticides was mostly below 80% and only 30 pesticides exceeded the ADI. In particular, non-treated EDI from pesticide residue data and food intake was summed up to about 43 ug/day/capita, and the rank was procymidone(8.6 ug) $gt; malefic hydrazide(8.2 ug) $gt; EPN(3.7 ug) $gt; deltamethrin(3.5 ug) $gt; cypermethrin(3.0 ug). The treated EDI calculated from pesticide residue data, food intake, and correction factor by culinary treatment was summed up to 13.7ug/day/capita. The percentage of ADI was TMDI(79.74%) $gt; non-treated EDI (0.17%) $gt; treated EDI(0.04%), and the exposure level of Korean population to whole pesticides was below the level to produce health risk. Oncogenic risk of five pesticides used in Korea whose oncogenic potency(Q*) was known were assessed from TMDI and treated EDI. Dietary oncogenic risk for Korean was estimated to be 2.0 × 10^(-3) on the basis of TMDI, 8.3 × 10^(-7) on the basis of treated EDI. The oncogenic risk from TMDI exceeded the risk level(1 × 10^(-6)) of EPA, whereas the oncogenic risk from treated EDI and real exposure level was lower than that of EPA.
Effect of storage temperature, washing, and cooking on postharvest-treated pesticide residues in polished rice was investigated. After being traeted with each 500 mg/kg of captan, carbaryl, phenthoate, fenthion, fenitrothion, chlorpyriphos-methyl, pirimiphos-methyl, the polished rice was stored for 8 weeks at 4 and 30℃, respectively. The penetation rate of carbaryl was the highest as 27.5% and the others, 13 to 18%. The half lives of pesticide residues were estimated as 30 to 230 weeks at 4℃, but 1 to 12 weeks at 30℃. The residues were reduced faster at 30℃ than at 4℃. The half lives of pesticide residues by water washing were estimated as 0.7 to 4.6 trials and the residues were removed with the washing trials. The residues of captan and carbaryl in cooked rice were removed 100 and 98%, respectively, comparing to initial residues concentration in treated rice but those of other 5 pesticides were removed 80%.