한방과 식품분야에서 널리 이용되고 있는 쑥의 특성 중 항미생물 효과에 대한 연구를 하였다. 쑥씨에서 분리한 정유를 GC, GC-MS로 분석한 결과 77종의 휘발성 물질이 동정되었고 그 중에서 가장 많이 존재하는 것은 campher(14.242%), borneol(12.812%), 1.8-cineol(6.437%), terpinen-4-ol(1.185%) 등으로 전체 정유성분의 약 35%를 차지했다. 이들 4종과 Mugwort seed extract(essential oil)를 가지고 대표적인 식품 미생물인 S. cerevisiae, L. mesenteroides, L. plantarum, A. oryzae와 B. subtilis 그리고 식품오염 정도의 지표 미생물인 E. coli 등의 생육에 미치는 항미생물 효과를 측정한 결과 terpinen-4-ol이 가장 효과가 커 1000ppm 정도로 미생물의 생육을 거의 억제시켰으나 cineol, essential oil은 효과가 그다지 크지 않은 반면에 borneol과 campher는 항미생물 효과가 미약했다.

1. 본 실험은 토양절지 동물의 분포, 우점도 및 다양도를 알기 위하여 수원근교 및 지리산지역에서 1986년 10월부터 1987년 4월까지 실시되었다. 2. 위 기간중 채집된 2,989개체를 동정한 결과 3목(目), 20과, 19종이 확인 되었다. 3. 우점도지수는 수원군집의 것이 지리산군집의 것보다 낮았으나 계절별로 구분하였을 경우 우점도지수의 변이는 지리산 군집에서 작았고 수원군집에서 크게 나타났다.

In this study, the effects of single and binary heavy metals toxicity on the growth and phosphorus removal ability of Bacillus sp.. known as be a phosphorus-removing microorganism, were quantitatively evaluated. Cd, Cu, Zn, Pb, Ni were used as heavy metals. As a result of analysis of variance of the half of inhibition concentration and half of effective concentration for each single heavy metal treatment group, the inhibitory effect on the growth of Bacillus sp. was Ni < P b < Z n < Cu < C d. A nd the inhibitory effect on phosphorus removal by Bacillus s p. w as N i < Pb < Z n < Cu < C d. When analyzing the correlation between growth inhibition and phosphorus removal efficiency of a single heavy metal treatment group, a negative correlation was found (R2 = 0.815), and a positive correlation was found when the correlation between IC50 and EC50 was analyzed (R2 = 0.959). In all binary heavy metal treatment groups, the interaction was an antagonistic effect when evaluated using the additive toxicity index method. This paper is considered to be basic data on the toxic effects of heavy metals when phosphorus is removed using phosphorus removal microorganisms in wastewater.

This study was initiated to isolate the microorganisms removing phosphorus (P) from domestic sewage and to investigate the effects of environmental factors on the growth and P removal of the isolated bacteria. Microorganisms isolated from the sewage were identified as Chryseobacterium sp., Stenotrophomonas maltophilia, and Bacillus licheniformis. Among them, Bacillus licheniformis was selected as the P removal microorganism. The environmental factors considered in this study included initial phosphorus concentration, temperature, pH, and carbon source. At initial P concentrations of 10, 20, and 30 mg/L, the P removal efficiencies were 100.0%, 84.0%, and 16.5%, respectively. At 20°C, 30°C, and 40°C, the P removal efficiencies were 0%, 75.8%, and 60.6%, respectively. The removal efficiencies of phosphorus according to pH were 1.6%, 91.7%, and 51.1% at pH 5, pH 7, and pH 9, respectively. Using glucose, acetate, and glucose + acetate as carbon sources yielded P removal efficiencies of 80.9%, 33.6%, and 54.1%, respectively. Therefore, the results from the study demonstrated that the P removal efficiencies of Bacillus licheniformis were the highest when the initial P concentration, temperature, pH, and carbon source were 10 mg/L, 30°C, 7, and glucose, respectively.

This study was conducted to evaluate the effect of phosphorus acid (H3PO3) addition to the horticultural bed soil on the initial growth of red pepper (Capsicum annuum L. cv.), cucumber (Cucumis sativus L. cv.), and kimchi cabbage (Brassica campestris L. ssp. pekinensis (Lour.) Rupr. cv.). The stem heights of red pepper and cucumber were 46.1% and 23.0% greater in the 50 mg/L of phosphorus acid treatment than the untreated (control). Further, the stem diameter of pepper and cucumber were 48.7% and 23.0% greater in the 50 mg/L of phosphorus acid treatment than the control. In addition, the number of kimchi cabbage leaves was 47.5% greater in the 50 mg/L of phosphorus acid treatment than the control. The dry weights of red pepper, cucumber and kimchi cabbage were 72.9%, 16.5%, and 30.4% heavier in the 50 mg/L than the control, respectively. Cations (K, Ca, and Mg) and total phosphorus (T - P) were quantitatively analyzed for these three horticultural crops. The concentrations of K, Ca, and Mg, and T - P were higher in the 50 mg/L of phosphorus acid than the control, respectively. Based on the results obtained in this study, it appears that treatment of phosphorus acid in horticultural bed soil enhanced the growth of red pepper, cucumber and Kimchi cabbage.

기존 선로구조물의 대부분은 준공된 지 상당한 시일이 경과되어 노후화가 많이 진행된 상태이다. 특히 기존 철도교량 중 판형교는 상당수가 준공으로부터 40~60년 이상 경과된 노후교량이며 도상 없이 거더에 침목이 직결되어 있어서 차량의 주행하중이 교량에 직접 전달되므로 유도상 교량과 비교하여 교량에 가해지는 충격 및 소음이 클 뿐만 아니라 동적인 충격과 진동도 상대적으로 크다. 따라서 기존선 판형교에 대한 적절한 유지관리 및 보수, 보강기술의 개발이 매우 시급하다. 본 연구에서는 기존선 판형교의 성능개선과 소음, 진동 문제 해결을 위해 기개발된 레일매립궤도 시스템의 특징을 소개하고, 레일매립궤도의 진동 및 소음 저감 성능을 평가하기 위해 길이 5m 침목이 설치되어 있는 무도상 판형교와 레일매립궤도를 적용한 판형교를 제작하여 동일한 가진 조건에 따라 발생되는 진동응답을 측정하고 분석하였다. 또한 실험에서 얻은 진동응답 데이터를 음향해석 모델의 입력데이터로 사용하여 방사소음해석을 수행하였다. 실험 및 해석 결과 레일매립궤도를 적용한 판형교가 무도상 판형교 보다 진동에서는 15.0~18.8dB정도 감소하고 소음의 경우 평균 7.7dB(A)정도 감소하는 것으로 확인되었다.

Bioremediation has been recognized as a suitable alternative to conventional methods of removing contaminants, and it uses fungi, bacteria and microalgae. In contrast to other organisms, microalgae are unique in that they have the ability to perform photosynthesis like plants and to utilize organic/inorganic carbon substrates, in a process called phytoremediation. Microalgae can populate a reaction site rapidly and enhance the bioremediation efficiency. In this study, Chlorella vulgaris was used to evaluate the removal potentials of the nutrients (N and P) and heavy metals (Cu and Zn) from swine wastewater. The optimum growth conditions for Chlorella vulgaris and the removal potentials of N, P, Cu, and Zn from synthetic wastewater using Chlorella vulgaris were investigated. Based on the results, the applicability of this microalga to on-site wastewater treatment was examined. Optimal growth conditions for Chlorella vulgaris were established to be 28℃, a pH of 7, and light and dark cycles of 14:10 h. As the concentrations of the nutrients were increased, the efficiencies of N and P removal efficiencies by Chlorella vulgaris were decreased in the single and binary mixed treatments of the nutrients, respectively. Further, the efficiencies of Cu and Zn removal also decreased as the heavy metals concentrations added were increased, both in the single and binary mixed treatments. In addition, the efficiency of Cu removal was higher than that of Zn removal. Our results indicate that Chlorella vulgaris could be used in treatment plants for the removal of nutrients and heavy metals from swine wastewater.

Removal of siloxane compounds is very important to protecting the biogas energy conversion system from decreased efficiency and parts damage. Among various siloxane removal technologies, adsorption towers are mostly used for performance and ease of operation. However, due to the difficulty of measuring the concentration of siloxane compounds in the gas stream and the complicated matrix of siloxane compounds, adsorption characteristics are not well known. In this study, the adsorption characteristics for multi siloxane components are experimentally studied. Four siloxane components are vaporized in the nitrogen stream supplied continuously to a lab-scale adsorption tank with commercially available silica gel or activated carbon and an FTIR (Fourier-transform infrared spectroscopy) analyzer was used for the online siloxane analysis to find out the adsorption characteristics. While a mixture of L2, L5, D4 and D5 adsorption capacity of silica gel and activated carbon are similar -11.13 and 11.56wt% respectively-adsorption characteristics of each adsorbent was well distinguished in terms of breakthrough behavior. Silica gel shows sequential breakthrough for each siloxane compound and a more noticeable unique time range for Rc > 1, while relatively simultaneous breakthrough was shown for activated carbon adsorbents.

The purpose of this study is to provide environmentally sound management on the import of waste electrical and electronic equipment (WEEEs) by investigating the hazardous elements, and the hazardous characteristics thereof, in this waste, and by reviewing the extant criteria causing them to exhibit an Annex III characteristic on Basel Convention. The investigation of imported WEEEs found that the importing volume has gradually increased since 2009 and 95.9% of imported WEEEs, which are mainly classified as Printed Circuit Board (PCB) and its scrap in 2015, is designated as restriction wastes. Also, it is important to designate and unify the hazardous element list and the characteristics of WEEEs because the analytical items and their test methods submitted in the test report are designated differently for each local authority. We confirmed that three kinds of criteria are applied to determine whether the target wastes are hazardous or not: the content criteria for 8 kinds of elements on import bans of wastes, the content criteria for 8 kinds of elements sufficient for allowing wastes to be imported, and the leaching criteria for 13 kinds of elements to classified as a specified waste. Among them, five elements (hexavalent chromium, arsenic, cadmium, lead, and mercury) are managed for the WEEEs in Korea. Therefore, it is necessary to catalog the total contents of hazardous chemicals caused by hazardous characteristics of other elements (beryllium, antimony, etc.), as can happen to WEEEs.

Inappropriate recycling/disposal processes that are caused by the illegal transboundary movement of electronic wastes (e-wastes) can have harmful effects on the environment and public health because of these wastes’ harmful components. Therefore, we must understand the current situation regarding the domestic management of exported/imported e-wastes and examine the international requirements according to the Basel Convention. In this study, the current management situation of e-wastes in domestic and foreign countries and the present recycling processes of companies in Korea are investigated to draw improvements when e-wastes are exported or imported. Most imported e-waste involves waste printed circuit boards (WPCB) and their scraps (more than 95.7 % of the total e-waste volume in 2015) to recover precious metals such as copper, silver, gold, etc. To distinguish between waste and non-waste under the Basel Convention, six items (① market for used electronic and electrical equipment (UEEE), ② residual life and appearance, ③ functional tests, ④ evidence of UEEE deals, ⑤ evidence of contracts to a trade partner, and ⑥ packaging and loading conditions) and a decision flowchart are considered to classify whether the end-of-life equipment is waste.

This study investigated the concentration of heavy metals in blast-furnace slag cement by changing the content ratio between blast-furnace slag and ordinary Portland cement for the safe recycling of blast-furnace slag in the cement industry. The analysis of the three main materials of the cement (ordinary Portland cement, blast-furnace slag, and the alternative raw materials), resulted in the ordinary Portland cement having the highest concentration of heavy metals. Also, it is concluded that the heavy metal content of blast-furnace slag cement is mainly attributed to the content of ordinary Portland cement. As the content of furnace slag during the manufacture of cement increases, the overall heavy metal content of the furnace slag cement becomes low. This was highly evaluated as a resource in the cement-production process, in respect of the effective recycling of resources and the safe management of hazardous materials.

The purpose of this study was to verify safe and environmentally-sound recycling of blast-furnace slag in the cement industry. This was accomplished by analyzing the heavy metal contents of three kinds of raw materials: blast-furnace slag, Portland cement, and the substitutes, which were mainly input into the manufacture of cement. The research revealed that, in the five samples tested, the heavy metal level in the blast-furnace slag cements (5.90 ~ 8.38 mg/kg for Cr6+) is lower than the ordinary Portland cement (11.04 ~ 14.92 mg/kg for Cr6+). This suggests that both raw materials have low heavy metal contents compared with the 20 mg/kg limit enforced by the autonomic convention in Korea. As for the substitutes, there was no decisive effect on the overall heavy metal content because of the low input ratio of 2.5%. Therefore, it is of high utility value to recycle the blast-furnace slag in the cement industry, considering slag can dilute the overall heavy metal contents in the cement products.

수은의 전과정 관리를 통한 환경배출 저감을 위한 미나마타 협약이 2017년 8월에 발효되면서 비준 절차를 진행하고 있는 우리나라 또한 수은을 함유한 제품 또는 폐기물을 친환경적으로 보관 및 폐기해야 한다. 우리나라는 의도적 사용을 위해 원소상 수은을 수입해 왔으나, 수은첨가제품 및 정광 불순물 등 비의도적으로 수은이 유입되어 왔다. 이렇게 비의도적으로 유입된 수은의 69%가 고농도 수은함유폐기물의 형태로 지정폐기물로 구분되어 지정폐기물 유입시설로 유입되고 있는 것으로 추정되고 있다. 그러나 수은함유 폐기물 매립시설 주변대기 중 수은 농도가 우려됨에 따라 수은함유 폐기물의 친환경적인 매립 관리기준과 함께 고수은함유폐기물의 회수 및 처리에 대한 관심이 높아지고 있다. 특히 수은은 대기로의 휘발량이 큰 금속으로 알려져 있으며, 수은함유 폐기물 매립지에서 원소상 수은의 형태로 전환되어 환경 중으로 재유입될 가능성이 있다. 국외의 경우 고농도 수은함유 폐기물의 회수 및 처리에 대한 기준을 두고 있으나 국내에서는 아직 수은 회수에 대한 법적 근거가 마련되어 있지 않은 상황이다. 본 연구에서는 국내 업체에서 발생하고 있는 고농도 수은함유폐기물(비철금속 발생 슬러지)을 대상으로 시간별 온도별에 따른 대상 폐기물 내 수은 함유량 및 용출량 실측을 통해 고농도 수은함유 슬러지 중 최대 비산율 및 온도별 속도상수를 구하고자 하였다. 이를 통해 고농도 수은함유 폐기물의 환경 중 수은 배출 저감 방향을 제시함으로 향후 수은함유 폐기물의 적정 관리기준 설정에 기초자료로 활용될 것으로 판단된다.

경건주의의 기원으로 간주되는 요한 아른트 (1555-1621)는 독일 근대사에 절대적인 영향을 끼친 인물이다. 루터교에서의 아른트의 위치와 평가는 중세 신비주의의 문헌 그리고 영성주의와 같은 종교개혁의 외적 문헌들이 그의 작품을 통해 17세기 개신교 안으로 흘러 들어왔다는 것에 달려 있다. 아른트는 자신의 주저 “참된 기독교에 관한 4권의 책” (1605-1610)을 통해 요한 타울러, 독일 신학, 앙겔라드 폴리그노, 그리스도를 본받아, 발렌틴 바이겔 그리고 파라첼수스 등을 수용하였다. 본 논문은 아른트의 기도 서적 “천국의 작은 정원” (1612)에 대한 문헌 비평이며, 이러한 문헌 비평을 통해 아직까지 밝혀지지 않은 중세 신비주 의자 버나드의 문헌 그리고 버나드의 영성 아래서 전승된 위 버나드 문헌들을 밝혀 낸 연구이다. 또한 아른트의 기도 서적 속에서 드러난 수난 신비주의, 신랑 신부 신비주의, 사랑의 신비주의, 예수 이름 신비주의 등 다양한 일치 신비주의는 버나드 없이는 이해가 가능하지 않다는 것을 보여주고 있다.

Load test is performed to obtain the data to evaluate load carrying capacity and check static & dynamic characteristics of a structure by estimating the real behavior of bridge due to loading the load. The subject facility in this paper is a bridge located on the spiilway of dam and traffic is relatively less than most brige. Considering the age and operation rules of a dam, however, load test and structure programming analysis were performed to check current conditions for structure under in-depth inspection and the results of that analysis are shown.