• 한국환경과학회지
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• 제19권4호
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• pp.483-490
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• 2010

The purpose of this study is to investigate the effect of influent phosphorus concentration on the nitrogen and phosphorus removal in sequencing batch reactor(SBR) and sequencing batch biofilm reactors(SBBRs) in order to recover the enhanced biological phosphorus removal (EBPR) capacity at the sludge of the deterioration of EBPR capacity. In SBBRs, comparing to SBR, the organic removal was occurred actively at the 1 st non-aeration period because of the active phosphorus release at this period. However, the variation of TOC removal according to the decrease of influent phosphorus concentration was not clearly shown both in SBR and SBBRs. In case of SBR losing EBPR capacity, the EBPR capacity was not recovered by the decrease of the influent phosphorus concentration from 7.5 mg/L to 0.9 mg/L. The nitrogen removal increased by the decrease of influent phosphorus concentration both in SBR and SBBRs.

• 건축역사연구
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• 제24권5호
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• pp.41-48
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• 2015

Quantitative analysis of termites damage is important in terms of conservation and maintenance of wooden cultural heritage buildings, because termites makes cavities and decreases the section area of wooden structural members. The purpose of this study is to forecast the range and spread of termites damage in the wooden structural members by using ultrasonic pulse velocity method. Ultrasonic pulse velocity has been used as one of non-destructive test to analysis the internal defect by using difference velocity between medium material and cavity. This method would be effective to analysis termites damages. From the result of the ultrasonic velocity test, the loss rate of area effected by termites damage had a strong correlation with ultrasonic velocity. And it is possible to predict the loss rate of area from by termites damage by using regression equation in the case of structural member of fine tree.

• 보존과학연구
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• 통권28호
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• pp.75-90
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• 2007

The ancient biomolecular remains are the potential source for paleobiology and paleoanthropology. Especially, ancient human specimens such as bone, teeth, and hair are powerful materials to identify historical origin and migration of ancestor population from the past. However, most excavated human specimens in archaeological sites have commonly problems as natural damage and exogenous contamination. We carried out histological and molecular analyses of excavated bone from the historic sites in South Korea from the recently discovered in tumulus of Seochun and Naju. Biological deterioration of bone was observed anatomically by optical and scanning electron microscope (SEM). We extracted degraded DNA, and amplified hyper variable region (HVR) of mitochondrial DNA (mtDNA) and amelogenin of nucleus DNA. This study applied and examined the relationships between histological preservation and DNA survival in excavated bone.

• 보존과학연구
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• 통권28호
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• pp.59-73
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• 2007

Wooden artifacts are biologically damaged by animals, insects, and micro-organisms. We focused on the evaluation of the antifungal and insecticidal activities of tree extracts to control deterioration of wooden cultural properties. 12 kinds of methanol extracts from 9 species of tree were investigated for their biocidal activities against two micro-organisms and two spices of insect. Most tree extracts showed fungicidal activities to Tyromyces palustris and Trametes versicolor. Among 12 different tree extracts, the strongest antifungal activity against T.palustris and T.versicolor was observed from the extracts of Pinus densiflora stem-bark extract and Pinus koraiensis leaf extracts. However, in the insecticidal activity test, Pinus densiflora stem-bark extracts against termite was relatively effective. Chemical compositions of methanol extracts were analyzed by gas chromatography/mass spectrometry. As a result, it was confirmed that development of biocide based on the natural extracts can be expected to conservate of wooden cultural properties.

• Advances in nano research
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• 제15권4호
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• pp.355-366
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• 2023

Biological corrosion, a crucial aspect of metal degradation, has received limited attention despite its significance. It involves the deterioration of metals due to corrosion processes influenced by living organisms, including bacteria. Soil represents a substantial threat to pipeline corrosion as it contains chemical and microbial factors that cause severe damage to water, oil, and gas transmission projects. To combat fouling and corrosion, corrosion inhibitors are commonly used; however, their production often involves expensive and hazardous chemicals. Consequently, researchers are exploring natural and eco-friendly alternatives, specifically nano-sized products, as potent corrosion inhibitors. This study aims to environmentally synthesize silver nanoparticles using an extract from Lagoecia cuminoides L and evaluate their effectiveness in preventing biological corrosion of buried pipes in soil. The optimal experimental conditions were determined as follows: a volume of 4 ml for the extract, a volume of 4 ml for silver nitrate (AgNO3), pH 9, a duration of 60 minutes, and a temperature of 60 degrees Celsius. Analysis using transmission electron microscopy confirmed the formation of nanoparticles with an average size of approximately 28 nm, while X-ray diffraction patterns exhibited suitable peak intensities. By employing the Scherer equation, the average particle size was estimated to be around 30 nm. Furthermore, antibacterial studies revealed the potent antibacterial activity of the synthesized silver nanoparticles against both aerobic and anaerobic bacteria. This property effectively mitigates the biological corrosion caused by bacteria in steel pipes buried in soil.

• 보존과학회지
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• 제17권
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• pp.5-18
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• 2005

논산 관촉사 석등은 암회색을 띠는 화강섬록암으로 구성되어 있다 이 석등은 전체적으로 S자형으로 뒤틀려 있으며 상대석과 1층 옥개석 하부에는 표면박리가 발생하여 석재의 표면이 심하게 부서지고 있다. 이차적 오염도 심각하여 . 부재사이에 삽입된 철편의 산화에 의한 변색과 강수의 유동흔적을 따라 나타나는 회백색 및 암흑색의 침전물이 산재한다. 석등의 표면에는 지의류와 선태류가 피복되어 있어 다양한 형태의 생물학적 훼손을 저감하기 위한 보존처리가 요구된다 또한 석등의 구조적 안정과 표면마모 및 기계적 풍화를 저지하기 위해 환경변화에 대한 장기적인 모니터 링과 함께 풍화요소를 저감할 수 있는 보존방법을 강구해야 할 것이다. 이 석등의 부재는 산출상태와 암석학적 및 지구화학적 특성이 주변의 기반암과 동일한 성인을 갖는 것으로 보아 주변의 석재를 이용하여 석등을 제작하였을 가능성이 높다.

• 보존과학회지
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• 제35권4호
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• pp.279-293
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• 2019

The stone lantern of the Damyang Gaeseonsaji temple site is a cultural heritage built during the Unified Silla period (AD 868). The reason for its value as a cultural property is due to wittern the background and the period created on inscription of the lamp stone engraved by letters. The stone lantern consists of two types of lithic tuffs for the 23 original properties, the replaced stones in 1991, and the biotite granite for its ground stones replaced in 2005. The lithic tuffs selected as the replacement parts in 1991 and 2017 have been examined and got to properties of hardly exposure moisture as well as very similar geochemical characteristics. There were various types of physical deterioration of the stone properties and structural cracks; in particular, on the northern side of the stylobates. Chemical and biological deterioration can be identified as black, white, and brown discolorations as well as by the presence of lichens, bryophytes, and herbaceous plants. In the evaluation of the physical properties of the stone lantern, the mean and maximum ultrasonic velocities were found to be similar in each direction. However, the lowest velocity on the east and south sides were found to be lower than those of other stone properties. It was found that physical damage to the stylobates resulted from water expansion in a freeze-to-thaw phenomena related to water content. Therefore, dismantling repair was carried out in the protection facility to restrict further water supply to the stone as much as possible.

• 한국환경복원기술학회지
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• 제12권3호
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• pp.142-163
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• 2009

Taebaek city is located in the mountainous plateau area therefore the major industry was coal industry. According to dramatically declining of the major industry, Taebaek city is need to alternative industry which associated with considering the geographical characteristics of natural tourism resources for increasing the local economy. On the basis of these reasons, this study can be suggested ecological planning and mitigation of deterioration technique about the these study site. That is the reserved area for mountainous experience theme park. As the results of environmental ecology assessment are following as; The natural ecosystem areas, multi-layer structure forest such as forest of Pinus densiflora, forest of Quercus mongolica and deciduous forest have a high value of nature, diversity and potential. In addition, wild bird habitats were important area as a inhabitation, breeding, feeding and hiding. Therefore, on these areas should be preserved. Also, it needs to conserve on there such as more than three types of wild bird inhabitate areas, the fringe of high biological diversity, the wetland that have got good vegetation condition and the function of amphibia, reptiles crossing. In addition, inhabitation, the waterway of wetland form that have got wide waterside width needs to conserve. In conclusion, on the basis of analysis results such as conditions of plan, environment, ecological assessments, survey informations are able to suggest the connectivity of the axis of forest and management plan. Moreover, in the part of forest restoration plan, we suggest the plan of transplant for a compensation of damaged forest by land use.

• 보존과학연구
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• 통권34호
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• pp.64-81
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• 2013

2001년부터 2005년까지의 국가지정 석조문화재의 정기조사 이후에 많은 석조문화재가 보수 보존처리 되었지만 아직까지 훼손상태 및 등급에 따른 보존처리 기준이 모호하다. 따라서 이 연구에서는 국가지정 석조문화재의 훼손유형 및 등급에 따른 보수 보존처리의 원인을 통계분석하여 석조문화재의 훼손등급과 보존처리의 상관도를 분석하였다. 이 결과, 석조문화재의 모든 훼손유형에서 3등급이 가장 높게 나타났으며, 이를 등급별로 보면 4등급은 풍화상태가 143건, 5등급은 생물영향이 61건으로 가장 많았다. 2002년부터 2011년까지 실시된 보존처리는 총 211건으로 집계되었다. 보존처리 유형은 표면세정(134건, 26.1%), 수지접합, 강화처리 등이 가장 많이 실시되었다. 석조문화재에 대한 직적접인 처리 이외에도 석조문화재의 보존환경을 안정적으로 유지하기 위해 보호각 설치, 배수로 정비, 주변정비공사 등이 실시되었다. 보존처리율은 전반적으로 훼손등급이 높아질수록 증가하는 것으로 확인되었다. 구성암석에 따라서는 변성암 및 퇴적암이 화성암으로 구성된 석조문화재 보다 상대적으로 높은 것으로 나타났다. 건조시대에 따라서는 삼국시대 석조문화재의 보존처리율이 가장 높게 나타났으며 통일신라시대, 고려시대, 조선시대에 축조된 석조문화재의 보존처리율은 유사한 것으로 확인되었다. 국가지정 석조문화재의 최대훼손등급에 따른 보존처리율 살펴보면, 5등급에서 매우 높은 약 80%정도의 비율을 보이며 2012년에 보존처리된 석조문화재 수를 합하면 보존처리율은 더 높아진다. 이 결과는 향후 국내 석조문화재의 훼손상태에 대한 보존처리 여부를 결정하는데 있어 기초자료로 제공될 수 있을 것이다.

• 보존과학회지
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• 제23권
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• pp.95-102
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• 2008

유기질 문화재 보존 천연 살생물제 개발을 위한 후보물질 조사를 위해 국내 자생하는 11종 수목을 대상으로 각 수목 메탄올 추출물의 9종 목재오염균과 궐련벌레 성충에 대한 항진균 및 살충활성을 조사하였다. 항진균 활성은 목재부후균과 표면오염균에 대해 각각 paper disc soaking 방법과 feeder strip 방법으로 측정되었다. 그 결과, 수목 중 황벽(Phellodendron amurense) 메탄올 추출물은 5 mg/disc에서 Coniophora puteana, Lentinus lepideus, Tyromyces palustris 그리고 Aspergillus niger에 대해 우수한 항균활성을 나타냈다. 또한, 수목 메탄올 추출물의 살충활성은 topical application 방법에 의해 측정되었으며 특히 주목(Taxus cuspidata)과 전나무(Abies holophylla) 메탄올 추출물을 궐련벌레 성충에 25 ${\mu}g$/adult의 농도로 24시간 처리했을 때 56.7%의 치사율을 보였다. 위의 결과로부터 주목과 전나무 그리고 황벽 메탄올 추출물은 각각 충과 목재오염균에 의해 야기되는 생물학적 열화에 대한 유기질 문화재 보존을 위해 유용하게 사용가능할 것으로 사료된다.