• Journal of Life Science
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• v.30 no.2
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• pp.156-161
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• 2020

Since industrialization, the production and utilization of various chemicals has contributed to improving the quality of our lives, but the subsequent discharge of massive waste is inevitable, and environmental pollution is becoming more serious every day. Exposure to chemicals as a result of environmental pollution is having a negative effect on human health and the ecosystem, and cleaning up the polluted environment that can affect our lives is a very important issue. Toxic aromatic compounds have been detected frequently in soil, groundwater, and wastewater because of the extensive use of oil products, and phenol, which is used to produce synthetic resins, textiles, and dyes, is one of the major pollutants, along with insecticides and preservatives. Phenol can cause dyspnea, headache, vomiting, mutation, and carcinogenesis. Phenol-degrading bacterium DWB-1-8 was isolated from the activated sludge of textile wastewater; this strain was identified as Comamonas testosteroni by 16S rRNA gene sequencing. The optimal culture conditions for the cell growth and degradation of phenol were 0.7% K₂HPO₄, 0.6% NaH₂PO₄, 0.1% NH₄NO₃, 0.015% MgSO₄·7H₂O, 0.001% FeSO₄·7H₂O, an initial pH of 7, and a temperature of 30℃. The strain was also able to grow by using other toxic compounds, such as benzene, toluene, or xylene (BTX), as the sole source of carbon.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.237-243
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• 1993

The primary and secondary structure of the 5S rRNA isolated from Xanthomonas celebensis were determined by enzymatic and chemical degradation methods. It consists of 119 nucleotides and contains no modified nucleosides. As with the 5S rRNAs of X. maltophilia and X. citri, it contains an additional uridine residue on the 5'-terminus. Its secondary structure was almost identical to the models previously proposed by us for the 5S rRNA of two Xanthomonas species. Its secondary structure consists of five helices, five loops and two bulges. The tertiary interactions in the 5S rRNA molecule were analyzed by Fe(II)-EDTA treatment and hybridization method using deoxyhexamer. From the fact that some adenine residues in loop M, region $I_1-C$, loop $H_1$, and loop $H_2$ become susceptible to diethylpyrocarbonate when the 5S rRNA was hybridized with deoxyhexamer complementary to the sequence $U_{35}CCCAU_{40}$ and that some nucleotide residues in loop M, loop $H_1$ and region $D-I_2$ become resistant Fe(II)-EDTA cleavage in the presence of $Mg^{2+}$, it is presumed that loops $H_1$ and $H_2$ interact with loop M in some way. In the tertiary interaction, the regions $I_1-C$ and $D-I_2$ seem to act as hinges in folding the stems $B-I_1-C$ and $D-I_2-E.$ It was found that loop $H_1$ changes into a smaller loop of three bases by forming noncanonical A : C base-pairs ih acidic environment.

• Resources Recycling
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• v.30 no.3
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• pp.30-40
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• 2021

The present study investigates the bioleaching efficiencies of arsenic via contact and non-contact mechanisms. The attachment of Acidithiobacillus ferrooxidans was restricted by a partition system comprising a semi-permeable membrane with a molecular weight cutoff of 12-14 kDa. The results were compared for two arsenic concentrations in the system (1.0% and 0.5% w/v) to maintain a homogeneous system. The overall bacterial performance was monitored by comparing total arsenic and iron concentrations, Fe ion speciation, pH, and solution redox potentials in flask bioleaching experiments over a period of 10 d. Our results indicated that bacterial attachment could increase arsenic extraction efficiency from 20.0% to 44.9% at 1.0 % solid concentrations. These findings suggest that the bacterial contact mechanism greatly influences arsenic bioleaching from mine tailings. Therefore, systems involving two-step or non-contact bioleaching are less effective than those involving one-step or contact bioleaching for the efficient extraction of arsenic from mine tailings.

• Applied Microscopy
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• v.41 no.2
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• pp.139-145
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• 2011

Parthenocissus tricuspidata is an epiphyte that lacks a main axial stem, but develops adhesive disks along the stem for climbing support. In this study, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were utilized to examine the brick wall surface and the adhesive disks of P. tricuspidata that attached to the surface successfully. The study was mainly focused the outermost layers of both structures before and after adhesion to find out whether there has been some structural and/or physical interactions between the two. The adhesive disks adhered firmly to the brick wall by secreting adhesive materials that help them for a tight attachment to the surface. The rough wall surface appeared facilitating better attachment of the adhesive disks by infiltrating the materials into those spaces leading to some degree of interactions at the interface. EDS analysis on the outermost layers of the adhesive disks that were separated from the substrates was also consistent with the SEM data on the interaction between the adhesive disks and the substrate surface. EDS analysis of the brick wall surface and the adhesive disks demonstrated similar elements of O, Si, Fe, Al, K, Mg, and Na in their components.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.157-157
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• 2003

우리나라에서 생산되는 감귤은 지리적 기후 조건으로 내한성이 강한 만다린계 온주밀감이 주종을 이루나 최근 과잉생산으로 인한 가격하락과 수입자유화에 따른 대처의 일환으로 경쟁력이 높은 품종을 장려 보급하고 있다. 감귤의 국내 연간 생산량은 56만 톤으로 과일 전체 생산량의 약 30%를 차지하며 과실의 약 20%가 과피로서 그 일부가 한약재로 쓰이나 대부분이 버려지고 있다. 감귤의 과피에는 carotenoids, bioflavonoids, pectin 및 terpenes가 풍부하게 함유되어 있으며, 천연에서 발견되고 있는 약 300여종의 carotenoids계 색소 중 115종이 감귤에 존재한다. 감귤 과피의 주요 carotenoids로는 비타민 A의 역할을 하는 $\beta$-carotene과 cryptoxanthin을 비롯한 $\beta$-citraurin이며 천연 착색제로 활용되고 있다. 또, 주요 bioflavonoids로는 모세혈관의 수축을 촉진시켜 고혈압 예방과 이로 인한 각종 질환을 방지하는 작용을 가진 hesperidin과 혈액내 LDL 콜레스테롤의 양을 줄이는 작용이 알려진 naringin이 있다. 그 외의 감귤 flavonoids도 항산화작용, antimutagen 활성, 항암, 항알레르기 및 항바이러스 효과가 알려져 있다. 밀감 과피의 bioflavonoids는 약 60여종이 분리되어 그 구조가 밝혀져 있으나 90% 이상이 hesperidin이다. 또 과피유에는 $\delta$-limonene을 주성분으로 하는 휘발성 향미성분이 함유되어 있어 향미 개선제로서의 활용이 기대되고 있다. 본 연구는 최근 식생활의 서구화로 쌀 위주의 식생활에 많은 변화를 가져와 쌀 소비량은 해마다 줄어들고 있는 반면 기능성을 가미한 쌀의 소비가 늘고 있음을 감안하여, 우리나라 제주도에서 생산되고 있는 감귤 과피의 물 균질액을 쌀에 코팅하여 아름다운 색상과 기능성을 지닌 유색미를 제조함과 동시에 그 취반 특성을 조사하였다. 그 결과 유색미의 색상은 진노랑(L＊; 63.6, a＊; -7.87, b＊; 46.35)으로 취반 후에도 유사한 색상을 나타내었다. Total carotenoids는 감귤과피에서는 10.74mg%, 과피의 물 균질액에는 0.46mg%이었으며 유색미에는 0.l2mg%, 유색미 취반에는 0.05mg%를 나타내었다. Hesperidin은 과피, 물 균질액, 유색미 및 유색미 취반에서 각각 2173.l2mg%, 108.65mg%, 21.73mg% 및 8.67mg%이었으며, naringin은 각각 1468.40mg%, 73.38mg%, 14.62mg% 및 5.87mg%를 나타내었다. 감귤과피의 유리아미노산은 asparagine이 94.22mg%로 가장 높았으며, methionine이 24.88mg%, alanine이 19.64mg%, ${\gamma}$ -aminoisobutylic acid가 15.37mg%로 이들 4종의 아미노산이 전체 유리아미노산함량의 70%를 나타내었다. 유색미 취반에는 백미 취반에 비하여 총 유리아미노산의 함량이 15%정도 증가되었으며, 그 중에서 glutamic acid는 2.5 배가 증가되었다. 감귤과피의 주요 무기질은 K(652.60mg%)와 Ca(222.50mg%)로 전체 무기질 함량의 86%를 차지하였으며 유색미 취반은 백미 취반에 비하여 K는 2.3배, Mn는 76%, Ca, P, Mg은 16~26%, Fe는 13%가 각각 증가되었다. 취반의 경도, 점착성 및 깨짐성은 유색미 취반과 백미 취반간에 차이가 없으나 응집성과 탄력성은 유색미 취반에서 높았다. 색상에 대한 기호도, 구수한 맛 및 종합적인 기호도는 유색미 취반에서 높았으며 단맛, 쓴맛은 백미 취반과 차이를 보이지 않았다.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.1-6
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• 2003

Chemical compositions of several herbs (rosemary, mint, thyme, sage, and lavender) cultivated in Korea were analyzed. Approximate compositions were as follows: moisture $69.92{\sim}82.10%$, crude ash $2.48{\sim}6.15%$, crude fat $0.40{\sim}2.46%$, crude protein $0.84{\sim}1.57%$, and crude fiber $2.48{\sim}6.15%$. Total contents of phenolics determined by Folin-Dennis's method were in the range of $73.24{\sim}197.79mg%$. Contents of minerals, Na, Ca, Mn, P, Mg, Zn, and Fe determined by ICP-AES were $43.0{\sim}112.5,\;177.5{\sim}304.0,\;0.5{\sim}1.5,\;74.0{\sim}218.5,\;57.0{\sim}116.0,\;1.0{\sim}2.0$ and $3.0{\sim}5.0mg%$, respectively. Free sugar contents determined by HPLC were: sucrose $0{\sim}7.61$, glucose $0.94{\sim}15.92$, and rhamnose $0.64{\sim}7.99mg%$. Fatty acids including palmitic, stearic, oleic, linoleic, linolenic, and arachidonic acids were identified by GC. Linoleic and linolenic acid contents were higher than those of palmitic and stearic acids. Aroma components identified by GC-MS were 1,8-cineole, ${\alpha}-phellandrene,\;{\alpha}-terpinene,\;{\beta}-pinene,\;{\beta}-thujone$, borneol, butan-1-ol, cis-sabinene hydrate, ${\delta}-carene,\;{\gamma}-terpinene$, and verbenone.

• Food Science and Preservation
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• v.9 no.4
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• pp.380-384
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• 2002

This study has been carried out to investigate the composition of fatty Acids, organic acids, minerals, vitamin C, total phenolics and saponin in 30$\^{C}$ hot air dried powder of main and lateral root of Acorus calamus L. Major saturated fatty acids were identified caprylic acid, pentadecanoic acid, stearic acid and heneicosanoic acid, etc.. Content of caprylic acid in main and lateral root were 28.35% and 31.44%. Unsaturated fatty acids such as linoleic acid, palmitoeic acid and linoleic acid was highly contented, linoleic acid was highest contented 25.55% in main root and 23.43% in lateral root. Succinic acid was the most abundant organic acid of root content of main and lateral root were 2,790 mg% and 2,630 mg%. Potassium was found to be the mon predominant mineral in root, followed by calcium, phosphorus and magnesium, in a order. Contents of potassium in main and lateral root account for 194 mg% and 454 mg%, respectively. Contents of these minerals in lateral root were higher value than that in main root. Contents of ascorbic acid and total phenolics were 113.8 $\mu\textrm{g}$/g and 463 mg％ in main root, 125.1 $\mu\textrm{g}$/g and 474 mg% in lateral root, respectively. Crude saponin content of main and lateral mot were high level amount, 2.51 ％ and 3.39 %.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.171-177
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• 2005

Nutritional compositions and antioxidative activity of Kabocha squash (Cucurvita maxima Duch) as health food were compared with those of pumpkin (Cucurvita moschata Duch). Kabocha squash had higher soluble solids and twofold harder flesh than pumpkin. Crude protein, crude lipid and total amino acid contents of Kabocha squash were higher than those of pumpkin. Major free sugar in Kabocha squash was sucrose, and its content were 2.1 times higher than that of pumpkin. Major organic acids of Kabocha squash and pumpkin were succinic and malic acid, respectively. Kabocha squash had higher amounts of vitamins $A,\;B_1,\;B_2,\;C$ and C than pumpkin, while both showed similar mineral contents except for iron. Contents of Total pectin and hydrochloric acid soluble pectin of Kabocha squash were 17.00 and 7.37 g/100 g AIS, respectively. In pumpkin, total pectin content was 25.14 g/100 g AIS, and water soluble pectin content was higher than those of other pectin fractions. Contents of carotenoid in Kabocha squash and pumpkin were 285.91 and 24,62 mg% d.b., respectively. Kabocha squash had higher electron-donating radical-scavenging activity, SOD-like activity and nitrite-scavenging effect than pumpkin.

• Economic and Environmental Geology
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• v.12 no.1
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• pp.41-49
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• 1979

A literature review is made on the physical and chemical characteristics of clay minerals in acidic solutions from the mineralogical and hydrometallurgical viewpoints. Some of the important characteristics of clays are their ability to cation exchange, swelling, and incongruent dissolution in acidic solutions. Various clay minerals can take up metallic ions from solution via cation exchange mechanism. Generally, cation exchange capacity increases in the following order : kaolinite, halloysite, illite, vermiculite, and montmorillonite. In acidic solutions, the cation uptake such as copper by clay minerals is strongly inhibited by hydrogen and aluminum ions and thus is not economically significant factor for recovery of metals such as uranium and copper. In acidic solutions, the cation uptake is substial. Swelling is minimal at lower pH, possibly due to lattice collapse. Swelling may be controllable with montmorillonite type clays by exchanging interlayer sodium with lithium and/or hydroxylated aluminum species. The effect of add on clay minerals are : 1. Division of aggregates into smaller plates with increase in surface area and porosity. 2. Clay-acid reactions occur in the following order: (i) $H^+$ replacement of interlayer cations, (ii) removal of octahedral cations, such as Al, Fe, and Mg, and (iii) removal of tetrahedral Al ions. Acid attack initiates, around the edges of the clay particles and continued inward, leaving hydrated silica gel residue around the edges. 3. Reaction rates of (ii) and (iii) are pseudo-1st order and proportional to acid concentration. Rate doubles for every temperature increment of $10^{\circ}C$. Implications in in-situ leaching of copper or uranium with acid are : 1. Over the life span of the operation for a year or more, clays attacked by acid will leave silica gel. If such gel covers the surface of valuable mineral surfaces being leached, recovery could be substantially delayed. 2. For a copper deposit containing 0.5% each of clay minerals and recoverable copper, the added cost due to clay-acid reaction is about 1.5c/lb of copper (or 0.93 lbs of $H_2SO_4/1b$ of copper). This acid consumption by clay may be a factor for economic evaluation of in-situ leaching of an oxide copper deposit.

• Annual Conference on Human and Language Technology
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• 1999.10e
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• pp.441-446
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• 1999

본 연구는 접속사를 통한 텍스트 통합 과정이 논리적 추론 종류에 따라 다른 정보처리 과정 혹은 다른 종류의 단원적 구조(modular structure in language processing)에 의해 처리되는지를 조사하기 위해 실시되었다. 또한, 접속사를 통한 추론 과정이 실어증의 증상 종류에 따라 다른 종류의 언어정보처리 손상이 있는지를 평가하기 위해 실시되었다. 실험에 참가한 환자는 이해성 실어증환자(Wernicke aphasic), 전반성 실어증 환자(Global aphasic), 표현성 실어증 환자(Broca aphasic) 등이었다. en 종류의 과제를 이용하였다. 한 과제는 앞 뒤 문장을 논리적 관계성을 표현하는 접속사를 채워 넣는 과제였고 다른 과제는 접속사가 포함된 텍스트가 옳은지를 판단하는 정오 판단 과제였다. 실험재료 문장에 사용된 접속사는 추가적인 정보를 제공하는 '그리고'와 대등 관계를 나타내는 '그러나' 및 인과 관계를 표현하는 '그래서' 였다. 이 세 종류의 접속사는 각기 다른 논리적 관계성을 나타낸다. 실험 결과는 실어증 환자가 전반적으로 채워 넣기 과제에서 보다는 정오 판단 과제에서 더 많은 실수를 보였으며, 표현성 실어증 환자보다는 이해성 실어증 환자가 더 많은 오류를 보였다. 또한, 세 종류의 접속사 중에 '그리고'가 표함된 텍스트에서 더 많은 실수를 보였다. 이 연구에서 나타난 흥미 있는 결과는 표현성 실어증 환자는 '그러나' 접속사가 포함된 텍스트에서의 수행이 '그래서'가 포함된 경우에서보다 좋은 반면에 전반성 실어증 환자는 '그래서'를 포함하는 텍스트에서의 수행이 '그러나'를 포함하는 텍스트에서의 수행이 더 우수해서 이중해리(double dissociation)가 나타난다는 사실이다. 이 결과는 선후 문장이 어떤 종류의 논리적 관계성을 지니는가에 따라 다른 종류의 정보처리가 진행된다는 것을 암시하는 결과이다.>$\textrm{cm}^2$.。C로 비교적 양호한 초전박막의 전기적 특성을 나타내었다.(Mg+Fe)비를 갖고 전자에 비해 Al이 풍부한 환경에서 생성되었으며, 따라서 활석과 연관되지 않은 녹니석은 생성시 광체와 인접한 화강아질 편마암에 의해 주로영향을 받았을 것으로 생각된다. 녹니석의 이러한 2가지 화학조성상의 경향은 녹니석과 공존하는 운모류나 각섬석류들의 화학분석결과와도 잘 일치한다. 이러한 결과는 이 지역의 활석 광상이 초염기성암 기원의 사문암이 열수변질작용을 받아 생성되었음을 명확하게 지시하며, 따라서 활석 광석내에 존재하는 녹니석은 활석의 근원 광물로서 녹니석편암 및 녹니석 편마암 매의 녹니석이 활석화되고 남은 잔존광물이 아니라, 주변암에 의해 성분상의 영향을 받은 열수와 사문암과의 변질교대작용에 의한 활석화과정 중에 주로 생성된 것으로 추정된다. 이러한 결과는 연구지역의 활석광상이 초염기성암의 사문암화 작용과 활석화 작용의 두 가지 변질작용에 의해 형성되어졌음을 알려준다.농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술은 통증이 적고, 입원기간이 짧고, 사회로의 복귀가 빠르며, 고위험군에 적용할 수 있고, 무엇보다도 미용상의 이점이 크다는 면에서 자연기흉에 대해 유용한 치료방법임에는 틀림이 없으나 개흉술에 비해 재발율이 높고 비용이 비싸다는 문제가 제기되고 있는 만큼