• 한국패류학회지
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• 제27권3호
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• pp.247-252
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• 2011

감마선 (Co-60)의 처리 유무에 따른 진주의 영향을 연구하고자 진주 핵의 색 변화를 분석하였다. 담수산 조개로 만든 진주 핵에 감마선 (Co-60) 을 조사하게 되면, 진주 핵의 색은 조사선량에 따라 갈색에서 흑갈색 내지는 검은 회색으로 변한다. 본 연구에서는 감마선 (Co-60) 을 조사하지 않은 진주 핵 2개와 선량별로 조사된 4종류의 진주 핵 8개를 분석 재료로 사용하였다. UV-vis에서는 선량별로, 육안으로 확인되는 진주 핵의 컬러 변화 분석을 한 결과 선량이 증가함에 따라 비례적으로 반사도가 낮아짐을 확인하였고, X-선 회절분석에서는 감마선 (Co-60) 의 조사선량이 증가하여도 진주 핵의 결정구조가 변하는 것은 관찰되지 않았고 결정성 (crystallity) 이 높아지는 것으로 측정되었다. 또한 전자스핀공명분석으로는 처음으로 진주 핵의 감마선 (Co-60) 조사여부를 증명하였다. 감마선 (Co-60) 이 조사되지 않은 천연 핵에서는 대칭적인 ESR 신호를 확인할 수 있었고, 감마선 (Co-60)이 조사된 진주 핵에서는 조사선량이 증가할수록 특징적 비대칭의 스펙트럼과 g-value를 갖고 있어 천연의 핵과 조사된 핵의 차이를 구별할 수 있었다. 또한 감마선 (Co-60) 조사선량이 증가할수록 비례적으로 비대칭성이 높아지는 것을 증명하였다. 따라서 감마선 (Co-60) 처리 유무에 따른 진주의 색 변화를 연구하기 위해서는 진주 핵의 색 변화에 대한 원인 규명 및 분석이 선행되어야 한다고 사료된다.

• 식물병연구
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• 제13권2호
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• pp.122-125
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• 2007

2006년 부산광역시 강서구 칼란코에 재배포장에서 잎에 점무늬병이 심하게 발생하였다. 이병 식물체를 채집하여 병징을 관찰하고 병원균 분리한 다음 균학적 특성을 조사한 결과는 다음과 같다. 병징은 잎의 앞뒤에 갈색 또는 암갈색의 작은 점무늬가 나타나는데, 아래 잎에서부터 병반이 생기고 크기는 $1{\sim}5\;mm$로 약간 괴사되면서 심할 경우 낙엽되었다. 균총은 벨벳트색, 회색 또는 회갈색이며 균사 생육적온은 $25^{\circ}C$와 $30^{\circ}C$이었다. 분생포자는 단생, 갈색이며 실린더, 곤봉형 또는 장타원형으로 횡격막이 $1{\sim}4$개 있으며 크기는 $24{\sim}65\;{\times}\;12{\sim}23\;{\mu}m$이었다. 분생포자경은 갈색, 격막은 $1{\sim}7$개가 있으며, 크기는 $32{\sim}135\;{\times}\;4{\sim}8\;{\mu}m$이었다. 이상과 같은 특징을 가진 병원균이 Stemphylium lycopersici임을 확인할 수 있었다. 따라서 이상의 결과를 종합해 볼 때 칼란코에 잎에 발생한 점무늬 증상을 S. lycopersici (Enjoji) Yamamoto에 의한 칼란코에 점무늬병이라고 명명할 것을 제안한다.

• 농업과학연구
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• 제4권1호
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• pp.105-111
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• 1977

전보(前報)에 이어 Trichosporon cutaneum의 lipase 생산(生産)에 미치는 당류(糖類)의 영향을 더욱 검토(檢討)하기 위(爲)하여 몇가지 당류(糖類)를 첨가(添加)한 대두분추출액(大豆粉抽出液) 기본배지(基本培地)를 151bs에서 20분간(分間) 살균(殺菌)하였을때 일어나는 pH 및 착색도변화(着色度變化), 착색물질(着色物質)이 균체(菌體)의 생육(生育) 및 lipase 생산(生産)에 미치는 영향, 그리고 $30^{\circ}C$에서 진탕 배양(培養)하면서 배양중(培養中)의 pH 변화(變化)와 균체(菌體)의 생육(生育) 및 lipase 생산(生産)과의 관계(關係)를 검토(檢討)하여 아래와 같은 결과(結果)를 얻었다. 1. 대두분추출액(大豆粉抽出液) 기본배지(基本培地)에 각중당류(各種糖類)를 첨가(添加)하여 살균(殺菌)하였을 때 일어나는 갈변(褐變)은 xylose 첨가구(添加區)가 가장 심(甚)하고 다음이 galactose와 mannose, glucose 첨가구(添加區)의 순(順)이 었고 maltose와 sucrose 첨가구(添加區)는 당무첨가구(糖無添加區)와 별차이(別差異)가 없었다. 2. 살균후(殺菌後)에 갈변(褐變)이 심(甚)한 것일수록 pH가 낮았다. 3. 살균중(殺菌中)에 형성(形成)된 착색물질(着色物質)은 당(糖)의 종류(種類)에 비(比)하여 균체(菌體)의 생육(生育)및 lipase 생산(生産)에 미치는 영향이 작았다. 4. lipase 생산량(生産量)이 많을수록 균체(菌體)의 생산량(生産量)이이 작았다. 5. 살균중(殺菌中)의 갈변(褐變)이 가장 심(甚)한 xylose 첨가구(添加區)에서는 균체(菌體)의 증식(增殖) 및 lipase 생산저해작용(生産沮害作用)이 약천(若千) 약화(弱化)되었다. 6. 균체(菌體)의 증식(增殖)이 왕성(旺盛)할수록 배지(培地)의 pH가 낮아졌다.

• 한국결정성장학회지
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• 제19권2호
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• pp.90-94
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• 2009

Mong Hsu rubies from Myanmar were heat treated in oxidizing(oxygen) atmosphere at $1650^{\circ}C$ for 1 hour. The investigations of the micro-structural defects in the samples before and after heat treatment have been carried out by the variety of analysis techniques of FTIR, UV-VIS-NIR and SEM-EDS. It was found that after heat treatment the dark blue cores region were disappeared and turned to orange red color with the presence of the dense cloudy brownish colored tiny particles in and near former blue zoning. As-received ruby samples only revealed the presence of FTIR absorption peaks of diaspore, boehmite and O-H stretching, at 1986, 2115 and $3078/3319\;cm^{-1}$ respectively. The UV-VIS-NIR absorption of as-received and heat treated ruby samples similarly showed peaks at 405, 554 and 693 nm associated with $Cr^{3+}$, but for the same samples, the absorption peak of heat-treated ruby samples at 693 nm was somewhat stronger than that of the untreated ruby samples. Especially the presence of $Cr^{3+}$ peaks at 659 and 675 nm was found obviously in as-received ruby samples only. The SEM-EDS investigation disclosed the micro-porous defect structures commonly related to the core regions of the untreated ruby samples, which after heat treatment in an oxidizing environment those defect features have been dissolved into the host phase resulting in the lightening or disappearance of the dark coloration of ruby core.

• Mycobiology
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• 제28권4호
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• pp.177-179
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• 2000

A soft rot of fruits caused by Rhizopus nigricans occurred on peach (Prunus persica var. vulgaris) in The Chinju City Agricultural Products Wholesale Marke during in summer season of 2000. The disease infection usually started from wounding after harvest fruits, and then moved to outside. At first, the lesions started with water soaked and rapidly softened and diseased area gradually expanded. In severely infected film house, the rate of infected fruits reached 65.2%. Numerous sporangiospores were produced on the diseased fruits. Most of the sporangiospores were appeared to be readily dispersed in the air. The mycelia grew surface of fruits and produced stolons. Colonies on potato dextrose agar at $25{\sim}30^{\circ}C$ white cottony at first becoming heavily speckled by the presence of sporangia and the browinish black at maturity, spreading rapidly by means of stolons fired at various points to the substrate by rhizoids. Sporangia were $85.3{\sim}243.5{\times}53.4{\sim}219.2\;{\mu}m$ in size and were globose or sub-globose with. somewhat flattened base. The color of sporangia was white at first and then turned black with many spores, and never over-hanging. Sporangiophores were $8.9{\sim}36.6\;{\mu}m$ in width, smooth-walled, non-septate, light brown, simple, long, arising in groups of $3{\sim}5$ from stolons opposite rhizoids. Sporangiospores was $9.7{\sim}24.8{\times}5.9{\sim}15.8\;{\mu}m$, irregular, round, oval, elongate, angular, and browinish-black streaked. Columella was $70.2{\times}149.7{\mu}m$. brownish gray, and umberella-shaped when dehisced. The causal organism was identified as. Rhizopus nigricans Lind on the basis of the morphiogical characteristics of the fungus. Rhizopus soft rot on peach (Prunus persica) caused by the fungi has not been reported in Korea. This is the first report of rhizopus soft rot on peach caused by Rhizopus nigricans in Korea.

• 한국균학회지
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• 제30권2호
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• pp.166-169
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• 2002

2002년 진주시 농산물 도매시장에서 Rhizopus stolonifer에 의한 감귤 무름병이 발생하였다. 병징은 처음 과일 껍질 부분이 수침상으로 물러지면서 급속히 진전되어 썩었다. 균사는 처음 흰색에서 연한 갈색으로 되며 검은색의 포자낭을 형성한다. 포자낭병은 처음 무색에서 회색을 나타내며 포자낭을 끝에 만들고 길이는 $900{\sim}4300{\mu}m$였다. 포자낭은 처음에 무색에서 나중에 검은색이고 아구형으로 크기는 $98{\sim}346{\mu}m$이다. 추축은 아구형 또는 타원형으로 직경은 $60{\sim}216{\times}72{\sim}143{\mu}m$이다. 포자낭포자는 담갈색으로 단포이며 구형 또는 타원형으로 크기는 $8{\sim}18.3{\mu}m$였다. 균사생육 적온은 $25^{\circ}C$였다. 이상과 같이 병원균의 균학적 특징과 병원성을 검정한 결과 이병을 R. stolonifer에 의한 감귤 무름병으로 명명할 것을 제안하고자 한다.

• 상하수도학회지
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• 제9권3호
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• pp.99-107
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• 1995

Various humic substances are widely distributed in natural water body, such as rivers and lakes and cause the yellowish or brownish color to water. The evidence that humic substances are precursors of THMs formation in chlorinated drinking water has been reported m the Jiteratures. For the reason of public health as well as aesthetics, needs for humic substances removal have been increased in the conventional water treatment processes. In this research, the characteristics of aluminium coagulation of humic acids and humic acids were investigated. The optimum pH and coagulants dosage to remove these materials simultaneously by coagulation were alto studied. The results are as followed; 1. UV-254 absorptiometry for measuring the concentration of aquatic humic acids showed good applicability and stable results. 2. The optimal pH range for humic acids removal by aluminium coagulation was 5 to 5.5, however, an increase in aluminium coagulant dosage could enhance the removal rate of humic acids in the wide pH range. 3. Coprecipitation of humic acids in the typical pH range of 6.5 to 8 in water treatment processes may require the sweep coagulation mechanism with the excess aluminium coagulant dosage. 4. Using PAC(poly aluminium chloride) or PASS(poly aluminium silica sulfate) as coagulants was able to expand the operating range for removing humic acids. 5. From the coagulation of humic substances(UV-254) and turbidity at pH range of 5.5 - 6.0 and alum dose of 86 ppm, the removal efficiency of turbidity from the reservoir water was above 90% and that of UV-254 was above 70%. 6. By using the reservoir water, the optimum condition of rapid mixing for simultaneous removal of turbidity and UV-254 absorbance was pH of 5.8 and LAS dose of 86 ppm, in this study.

• Animal Systematics, Evolution and Diversity
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• 제26권1호
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• pp.15-19
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• 2010

The Russian ratsnake, Elaphe schrenckii, is found in Russia, China, and Korea, and is considered to be an endangered species by the Ministry of Environment in South Korea. Due to habitat loss and use in oriental medicine, their population has been severely decimated. In South Korea, two subspecies of E. schrenckii has been defined according to body color: E. s. schrenckii (blackish) and E. s. anomala (yellow-brownish). Molecular genetic studies on Elaphe schrenckii are very scarce and the taxonomy of Elaphe schrenckii subspecies is uncertain. From the present study, we attempted to identify the genetic differences of these two subspecies using species-specific microsatellites developed from the genomic library of E. schrenckii. Nine polymorphic loci were tested on 19 individuals from E. s. schrenckii (n=10) and E. s. anomala (n=9) in South Korea. The mean number of alleles was 3.78 in E. s. schrenckii and 4.11 in E. s. anomala. The average expected heterozygosity was 0.542 and 0.511 in E. s. schrenckii and E. s. anomala, respectively. We found a lack of genetic structure between two subspecies ($F_{ST}=0.016$) and no genetic discrimination between two subspecies was found. Based on the present findings by microsatellites, two subspecies can be considered as one species, E. schrenckii. However, further investigations on taxonomical status using mitochondrial and nuclear DNA sequences need to be performed and morphological & ecological data should be revised. The genetic markers should benefit future studies of the endangered species of other Elaphe species for the study of genetic diversity and potential conservation management.

• 한국식품영양과학회지
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• 제28권6호
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• pp.1212-1219
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• 1999

The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.199-204
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• 2006

The purpose of this work was to evaluate the development of the anammox process by the use of granular sludge selected from a digestion reactor as a potential seed source in a lab-scale UASB (upflow anaerobic sludge blanket) reactor system. The reactor was operated for approximately 11 months and was fed by synthetic wastewater. After 200 days of feeding with $NH_4^+\;and\;NO_2^-$ as the main substrates, the biomass showed steady signs of ammonium consumption, resulting in over 60% of ammonium nitrogen removal. This report aims to present the results and to more closely examine what occurs after the onset of anammox activity, while the previous work described the start-up experiment and the presence of anammox bacteria in the enriched community using the fluorescence in situ hybridization (FISH) technique. By the last month of operation, the consumed $NO_2^--N/NH_4^+-N$ ratio in the UASB reactor was close to 1.32, the stoichiometric ratio of the anammox reaction. The obtained results from the influent-shutdown test suggested that nitrite concentration would be one key parameter that promotes the anammox reaction during the start-up enrichment of anammox bacteria from granular sludge. During the study period, the sludge color gradually changed from black to red-brownish.