• 생태와환경
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• 제41권2호
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• pp.128-136
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• 2008

An attempt was made in the Veeranam freshwater lake with the objectives to collect, identify, describe and document the algae occurring from March 2007 to August 2007. Qualitative and quantitative characterization of phytoplankton and analysis of physico-chemical parameters of water samples were carried out at monthly intervals during the study period in the western and eastern sides of the lake. It was found that the phytoplankton community embraced 68 genera belonging to four classes viz., Bacillariophyceae (40), Chlorophyceae (22), Cynophyceae (4) and Euglenophyceae (2). There were significant influences of various physico-chemical parameters on the phytoplankton population density. Commonly occurred genera, Oscillatoria (Cyanophyceae), Navicula (Bacillariophyceae) and Scenedesmus (Chlorophyceae), were subjected to energy dispersive spectroscopic analysis (EDS). They were found to accumulate different elements such as Zn, P, S, Ca, Mg, Fe, N, Si, Cl and Mn. Among these the member Cyanophyceae contained Zn, P, Mg, Ca, Mn, S and N. Bacillariophyceae Si, Zn, Mg, Cl, N, Fe, and Ca. Chlorophyceae Ca, Mg, N, Fe, Cl, Zn, Si and Mn. Thus these observations would determine the chemical dialogue between the cell structures and role of the elements. Further, it gives the clue about the phytoplankton growth requirements.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.984-990
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• 2014

Polymers are the most commonly used di-electrics because of their reliability, availability, ease of fabrication and cost. The commercial and industrial demand for advanced polymeric materials which are capable of being used in harsh environment is need of the hour. The study of the effect of electron beam irradiation on polymeric materials is an area of rapidly increasing interest. This paper discusses the resultant beneficial effects of electron beam irradiation on the SiR-EPDM blend having 50:50 composition. The changes in mechanical and electrical properties of SiR-EPDM blend which are exposed to three different doses of electron beam radiation namely 5 Mrad, 15 Mrad and 25 Mrad are presented. The irradiated blends are analyzed for their electro-mechanical and physico chemical properties. The electrical changes induced by irradiation are investigated by arc resistance, surface resistivity and volume resistivity measurements as per ASTM standards. The mechanical changes are observed by the measurement of tensile strength and elongation at break. Physico chemical investigation has been done using the FTIR, in order to investigate the irradiation induced chemical changes.

• 유기물자원화
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• 제16권1호
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• pp.70-78
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• 2008

본 연구에서는 경기도 B지역 학교 폐기물의 성상 및 물리 화학적 특성을 조사하였다. 이것은 폐기물 재활용 및 자원화시설 설계를 위한 기초자료로 활용할 수 있게 하고자 한다. 학교폐기물의 물리적 조성의 실험결과 음식 쓰레기 12.25%, 종이류 56.26%, 플라스틱과 비닐류 9.26%, 섬유 1.52%, 나무 3.70%, 고무 및 피혁류와 기타는 0.11%이다. 학교폐기물의 대부분은 종이류와 플라스틱류이고, 약 90%가 가연성분인 것으로 나타났다. 삼성분 분석 결과 수분 5.72%, 가연분 88.29%, 그리고 회분 5.98%로 나타났으며, 농촌지역 학교 폐기물 성분중 수분이 도시지역 학교보다 높게 나왔다. 건조된 폐기물의 원소 분석 결과 탄소, 산소, 수소가 높게 나왔으며 학교폐기물의 저위발열량은 3051.44kcal/kg로 조사되어졌다.

• 한국축산식품학회지
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• 제21권1호
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• pp.71-79
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• 2001

Emulsion-type sausages were manufactured to investigate the effects of CLA-vegetable oils and CLA-lard on quality of emulsion-type sausage. Each treatments replaced pork back fat with CLA-sesame oil (CLA-SO), CLA-lard (CLA-LD) and CLA-safflower seed oil (CLA-SSO) were stored during 1, 7, 14, 21 and 28 days at 4$^{\circ}C$. The changes in physico-chemical properties, thiobarbituric acid reactive substances(TBARS) and fatty acid composition of each treatments were measured during 1, 7, 14, 21 and 28 days at 4$^{\circ}C$. The pH values of all treatments significantly(p<0.05) decreased as storage time increased. Sausage products containing CLA-vegetable oils showed higher pH value than that of CLA-lard among the treatments. Color a*-value of CLA-SSO was higher than that of other treatments. During storage, TBARS values of treatments were significantly (p<0.05) increased, sausage products containing CLA-vegetable oils showed lower (p<0.05) TBARS value than CLA-lard, and TBARS of sausage products containing CLA-SSO was the lowest. This result indicated that CLA concentration in emulsion-type sausage did affect the lipid oxidation stability. Fatty acids composition was changed by addition of CLA-vegetable oils and CLA-lard. All kinds of fatty acids content decreased whereas CLA content extremely increased by replacement of CLA-vegetable oils and CLA-lard. The level of CLA content in CLA-vegetable oils was higher than CLA-lard. It may be concluded that emulsion-type sausage could be manufactured using CLA-vegetable oils as a pork fat substitutor without any negative effects on general components or physico-chemical properties.

• Mass Spectrometry Letters
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• 제9권3호
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• pp.81-85
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• 2018

In this study, the chemical composition of bacterial melanin isolated from the Streptomyces glaucescens strain was elucidated by ultra-high-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Ultra-high-resolution mass profiles of the microbial melanin product were acquired using a 15 Tesla FT-ICR mass spectrometer in positive and negative ion modes via electrospray ionization to obtain more complete descriptions of the molecular compositions of melanin-derived organic constituents. A mass resolving power of 500,000 (at m/z 400) was achieved for all spectra while collecting 400 scans per sample with a 4 M transient. The results of this analysis revealed that the melanin pigment isolated from S. glaucescens predominantly exhibits CHON and CHO species, which belong to the proteins class of compounds, with the mean C/O and C/N ratios of 4.3 and 13.1, thus suggesting that the melanin could be eumelanin. This analytical approach could be utilized to investigate the molecular compositions of a variety of natural or synthetic melanins. The compositional features of melanins are important for understanding their formation mechanisms and physico-chemical properties.

• 한국식품과학회지
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• 제24권4호
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• pp.311-314
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• 1992

역삼투 방법을 이용한 두부순물의 정화시 역삼투 잔사의 활용 가능성을 검토하기 위해 두부순물 농축물의 성분 특성 및 분리 단백질의 기능성을 조사하였다. 두부순물의 역삼투 잔사 농축물에는 자당, 라피노오스 및 스타치오스가 건물 중으로 각각 32.59%, 4.76% 및 9.99% 함유되어 있었고, 무기물중 칼륨이 5.23%로 회분의 42.7%를 점하였다. 또한 조단백질 함량은 18.69%이었으며 아미노산 조성 및 전기영동상의 sub-unit 양상은 분리 콩단백질과 다소 차이를 보였다. 한편 두부순물로부터 분리한 단백질의 기능성중 pH에 따른 용해도는 분리 콩단백질에 비해 전반적으로 다소 높은 값을, 유화능과 유화안정성 및 점도는 분리 콩단백질보다 비교적 낮은 값을 나타냈다.

• 한국해양공학회지
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• 제19권4호
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• pp.42-48
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• 2005

The sediment of Shihwa Lake contains an abundant quantity of cohesive sediments. The transport processes of the cohesive sediments are complex and difficult to predict, quantitatively. The cohesive sediments are the primary reason for the pollution of the environment and water quality in the coastal region. In this study, a column test has been performed. In order to quantify the settling velocities of sediment from Shihwa Lake, an experiment was conducted using a specially designed 1.8m tall settling column. A series of settling tests and physico-chemical property tests on Shihwa Lake cohesive sediments has been conducted to investigate the correlation between settling properties and their physico-chemical properties, which are represented as grain size distribution, mineralogical composition, and percentage oj organic contents. Experimental results of physico-chemical property tests show that Shihwa Lake sediments are relatively large in average grain $size(74\mu m)$ contain very small organic $material(6\%)$, and are dominantly composed of Quarts, which has relatively low cohesion. Thus, Shihwa Lake sediments might be specified as those whose settling properties are more influenced by gravity than cohesion. It is concluded that the magnitude of settling velocities of muddy sediments can be quite different, regionally, and it implies that field or laboratory experiments for settling velocity measurement should be preceded over the numerical modeling of muddy sediment transport, in order to obtain the reliable prediction results for a given specific site.

• 한국축산식품학회지
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• 제23권1호
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• pp.16-20
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• 2003

본 연구는 쑥 분말을 돼지 사료에 첨가하여 0, 1, 3%의 비율로 비육후기 30일간 급여한 후 도축하여 4$^{\circ}C$에서 7일간 저장하면서 이화학적 특성에 대한 연구를 수행하였다. 대조구에 비하여 처리구(T1, T2)에서 조지방 함량이 약간 낮은 경향이었다. pH와 TBARS는 대조구에 비하여 처리구에서 유의적으로 낮았다. 저장기간이 경과함에 따라 pH, TBARS, VBN와 보수력은 증가하는 경향을 나타내었다(p<0.05). 돈육의 주된 지방산은 oleic acid, palmitic acid, linoleic acid와 stearic acid이었다. 처리구는 대조구에 비하여 linoleic acid와 linolenic acid 함량이 높은 경향이었다.

• 한국식품과학회지
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• 제27권5호
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• pp.768-772
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• 1995

건 구기자와 볶음조건을 달리한 볶은 구기자의 열수 추출물에 대하여 여러 가지 이화학적 특성을 조사하였다. 건 구기자의 일반성분은 수분 17.5%, 회분 5.4%, 지방 14.7%, 단백질 18.9%, 섬유질 12.8%, 당질 31.7%였다. 열수 추출시 추출수율은 볶음온도와 시간이 증가할수록 가용성 고형분이 더 빨리 추출되었으며, 색도는 명도가 감소하고 적색도가 증가하여 추출물이 더 진한 갈색을 나타내었고 탁도 역시 증가하였다. pH는 볶음온도와 시간이 증가할수록 5.08에서 4.38로 감소하였고 산도는 0.09%에서 0.16%로 증가하였다. 유리당 함량은 볶음온도와 시간이 증가할수록 감소하였고 특히 glucose함량이 0.45%에서 0.12%로 크게 감소하였다. 지방산 조성은 건 구기자에 비해 볶음온도와 시간이 증가할수록 linoleic acid의 비율이 감소하고 palmitic acid의 비율이 증가하였다. 관능검사 결과는 볶음온도와 시간이 증가할수록 단 냄새, 탄 냄새, 신 맛, 탄 맛, 떫은 맛 등은 증가하였고 단 맛과 구수한 맛은 약간 감소하였다.

• 한국식품과학회지
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• 제12권4호
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• pp.324-327
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• 1980

비자유(榧子油)의 물리화학적 특성을 조사한 결과는 다음과 같이 요약될 수 있다. 1) 일반분석치는 수분 12.33%, 조단백질 9.46%, 조지방질 54.29%, 섬유소 5.28%, 회분 2.13%로서 조지방 함량이 대단히 높음을 알 수 있다. 2) 비자유(榧子油)의 비중은 0.92, 굴절율은 1.47, 요드값은 127, 비누화값은 182.2, 산값은 9.5, 에스테르값은 172.7이었다. 3) 지방산의 조성은 미리스트산, 팔미트산, 스테아르산, 아라키드산 등의 포화지방산이 10%이하이며, 불포화지방산 인 올레산 31.68%, 리놀레산 46.77%, 리놀렌산 0.38%로서 리놀레산의 함량이 높고 리놀렌산은 대단히 적었다.