• Corrosion Science and Technology
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• 제6권4호
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• pp.164-169
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• 2007

Hydrogen induced cracking (HIC) was studied phenomenologically and the effect of microstructure on HIC was discussed for the steels having two different levels of nonmetallic inclusions. Steels having different microstructures were produced by thermomechanically controlled processes (TMCP) from two different heats which had the different level of nonmetallic inclusions. Ferrite/pearlite (F/P), ferrite/acicular ferrite (F/AF), ferrite/bainite (F/B) were three representative microstructures for all tested steels. For the steels with higher level of inclusions, permissible inclusion level for HIC not to develop was different according to steelmicrostructure. On the contrary, HIC occurred also at the martensite/austenite (M/A) constituents regardless of steel microstructure when they accumulated to a certain degree. It was proved that M/A constituents were easily embrittled by hydrogen atoms. Steels having F/AF is resistant to HIC at a given actual service condition since they covers a wide range of diffusible hydrogen content without developing HIC.

• 한국식품조리과학회지
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• 제11권4호
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• pp.386-395
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• 1995

미나리(Oenanthe javanica D.C)의 향기성분의 추출방법, 부위별 및 열처리 방법에 따라 미나리의 향기 성분을 분석한 결과는 다음과 같다. 수증기 증류법에 의해 추출된 성분은 23종의 성분, Head space법에서는 8종의 성분, Ether 추출법에서는 16종의 성분, Tenax-GC법에서는 9종의 성분이 확인되어 향기성분 조성은 추출방법에 따라 상당한 차이를 나타냈고, 수증기 증류법에 의해 추출하였을때 가장 많은 종류의 성분이 검색되었다. 부위별 미나리 향기성분을 분석한 결과, 향기성분의 함량은 줄기와 잎에서 각각 41.71 mg%, 85.37 mg%로 잎에서의 함량이 줄기보다 더 높았다. 줄기 부위에서는 hydrocarbon류 14종, aldehyde류 5종, alcohol류 4종으로 23종의 성분을 잎 부위에서는 hydrocarbon류 21종, aldehyde 5종, alcohol류 4종, ester 1종으로 31종의 성분을 확인하였으며, 잎 부위가 줄기에 비하여 비교적 다양한 종류의 향기 성분이 검출되었다. 줄기에서는 octanal 함량이 가장 높았고, limonene, sabinene, -terpinene, -myrcene 함량이 높았으며, 잎에서는 octanal 함량이 가장 높았고, isobicyclogermacrene, limonene, -farnesene, undecaethiol, -terpinene, sabinene, elemene, -myrcen 함량이 높았으며, 이들이 미나리의 중요한 향기성분이라 할 수 있다. 또한 열처리 방법에 따라 미나리의 향기성분 조성이 변화되었으며, 1000 $m\ell$에서 열처리한 미나리가 생시료 미나리의 향기성분과 가장 유사하였고 향기 성분 함량이 가장 높았다.

• Journal of Welding and Joining
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• 제26권3호
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• pp.51-60
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• 2008

This paper is to evaluate fracture characteristics of API 2W Gr.50 TMCP steel weldment typically applied for offshore structures, with the focus on the influence of heat input arising from flux cored arc welding. Based on the results and insights developed from this study, it is found that the toughness for both CTOD and impact exhibits a tendency to decrease as the weld heat input increases. The reheated zone of weldmetal exhibit lower hardness than solidified zone and microstructure that are liable to affect the toughness are acicular ferrite and martensite-austenite constituents (M-A). In particular, M-A is a more effective micro-phase for CTOD toughness than impact toughness.

• Natural Product Sciences
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• 제8권3호
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• pp.94-96
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• 2002

Four hundred varieties of plant extracts were screened for inhibitory activity against the NFAT transcription factor which plays an important role in inducing immune response. Among them, the MeOH extract of Cnidium officinale showed potent activity, and the activity-guided separation yielded butylidenephthalide, senkyunolide A and falcarindiol as the active constituents. The $IC_{50}$ value of butylidenephthalide was $1.3{\times}10^{-4}\;M$ and was similar to that of senkyunolide A $(2.1{\times}10^{-4}\;M)$. Interestingly, falcarindiol showed higher activity $(IC_{50},\;2.6{\times}10^{-5}\;M)$ than the two phthalides.

• 한국수산과학회지
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• 제11권3호
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• pp.129-138
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• 1978

The contents of inorganic conservative constituents in the downstream water were determined in spring tides of every month from May 1977 to April 1978 at eight stations of Nagdong River. Samples were taken at the intervals of one or two hours from 7 a. m. to 7 p. m. at each station. Annual ranges and means of the chemical constituents over all the stations except station one, Kupo, ate as follows: pH 6.4-9.3, 7.7; electrical conductivity $0.085-0.345\times10^3\;\mu\mho/cm,\;0.196\times10^3\;\mu\mho/cm;$ chloride 5.8-50.0ppm, 17.7ppm: fluoride ND-0.19 ppm, 0.06 ppm: sulfate 5.5-41.1 ppm, 20.7 ppm; calcium 6-26 ppm, 17 ppm; magnesium 2.0-12.8 ppm, 5.1 ppm; sodium 7-26 ppm, 13 ppm; potassium 1.4-3.8 pprn, 2.3 ppm respectively. The seasonal variations of contents of the chemical constituents were not large and showed nearly definite values at all the stations except station one, Kupo. At station one, seasonal variations were large and the contents were excessively high due to inflow of seawater compared with other stations. The values over 50 ppm in chloride were not determined during the determination period at Mul Geum where the intake station for Busan city water is located. Most constituents except pH and fluoride were over the criteria for drinking water at Kupo, while at other stations only pH value was exceeded the upper limit of the criterion especially in summer period. The pH values tended to increase in the afternoon when water temperature was high. The chloride concentration was shown the highest value at station one, Kupo, with about 2 hours delay after high water of Busan harbour and 3-3.5 hours at Mul Geum.

• Natural Product Sciences
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• 제23권4호
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• pp.247-252
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• 2017

The methylglyoxal (MGO) trapping constituents from onion (Allium cepa L.) peels were investigated using pre-column incubation of MGO and crude extract followed by HPLC analysis. The peak areas of MGO trapping compounds decreased, and their chemical structures were identified by HPLC-ESI/MS. Among major constituents in outer scale of onion, 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (2) was more effective MGO scavenger than quercetin (6) and its 4'-glucoside, spiraeoside (3). After 1 h incubation, compound 2 trapped over 90% MGO at a concentration of 0.5 mM under physiological conditions, but compounds 3 and 6 scavenged 45%, 16% MGO, respectively. HPLC-ESI/MS showed that compound 2 trapped two molecules of MGO to form a di-MGO adduct and compounds 3 and 6 captured one molecule of MGO to form mono-MGO adducts, and the positions 6 and 8 of the A ring of flavonoids were major active sites for trapping MGO.

• 생약학회지
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• 제9권2호
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• pp.57-72
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• 1978

The constituents of Ranunculaceae plants are summerized from more than one hundred of papers. Fifteen steroidal alkaloids, thirty two of terpenoids (diterpenes and triterpenes), fifty four isoquinoline alkaloids are recorded. Thirty three papaverines, eighteen berberines, and three hydrastines belong to isoquinoline group. Besides, of alkaloids a number of glycosides are also found. Adonis glycoside, famous cardiotonics, from Adonis and cyanogenin glycoside and calthoside D were identified from the leaves of Thalictrum aquilegifolium and Caltha silvestris. Anemonin, the irritating substance, found in Pulsatilla grandiz $W_{ENDER}$. Kaempf-erol and dihydrokaempferol were isolated and identified from the leaves of Clematis brachyura ^M_{AXIMOWICZ}$ by author in 1968.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3429-3436
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• 2013

Cervical cancer is a major health problem worldwide and is the most frequent cause of cancer in women in India. Early detection and affordable drugs with clinical efficacy have to go hand-in-hand in order to comprehensibly address this serious health challenge. Plant-based drugs with potent anticancer effects should add to the efforts to find a cheap drug with limited clinical side effects. Keeping this very purpose in mind, an attempt has been made in this review to explore the potential of plant extracts or constituents known to exhibit antitumorigenic activity or exert cytotoxic effect in human cervical carcinoma cells. Alkaloids such as those isolated from C. vincetoxicum and T. Tanakae, naucleaorals A and B, isolated from the roots of N. orientalis, (6aR)-normecambroline, isolated from the bark of N. dealbata appear promising in different human cervical carcinoma cells with the $IC_{50}$ of 4.0-8 ${\mu}g/mL$. However, other compounds such as rhinacanthone and neolignans isolated from different plants are not far behind and kill cervical cancer cells at a very low concentrations. Among plant extracts or its constituents that enhance the effect of known anticancer drugs, noni, derived from the plant M. citrifolia perhaps is the best candidate. The cytotoxic potency and apoptotic index of cisplatin was found to significantly enhanced in combination with noni in different human cervical carcinoma cells and it therefore holds significance as promising herbal-based anticancer agent. However, efficacy needs to be further investigated in various cervical cell lines and more importantly, in in vivo cervical cancer models for possible use as an alternative and safe anticancer drug.

• Natural Product Sciences
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• 제6권1호
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• pp.11-15
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• 2000

Two soyasaponins were isolated from the aerial parts of Astragalus tribuloides Del. Their structures were established on the basis of spectroscopic and chemical methods. In addition, ursolic acid, ${\beta}-sitosterol\;{\beta}-D-glucoside$ and isorhamnetin 3-O-glucoside were isolated and identified by comparing their mp, spectral and chromatographic data with those of authentic samples. This is the first report of screening and isolation of the chemical constituents of this species of genus Astragalus.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.63-63
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• 2003

Opuntia ficus-indicavar. saboten Makino (Cactaceae) is a tropical or subtropical plant that has been widely used as folk medicine for the treatment of diabetes, asthma, burn, edema and gastritis. The purposes of the present study were to identify antioxidant constituents from fruits and stems of the plant cultivated in Cheju island, Korea, and examine their in vitro neuroprotective activities. Using a chromatographic fractionation method, ten chemical constituents were isolated from ethyl acetate extracts. By means of chemical and spectroscopic methods, those were identified as eight flavonoids such as kaempherol (a), quercetin (b), kaempferol 3-methyl ether (c), quercetin 3-methyl ether (d), narcissin (e), dihydrokaernpferol (f), dihydroquercetin (g) and erioclictyol (h), and two terpenoids such as 3-oxo-${\alpha}$-ionol-${\beta}$-d-glucopyranoside (i) and roseoside (j). Among the isolated compounds, comrounds c~e and h~j were those reported for the first titre from the plant. Compounds b, d and g showed DPPH free radical scavenging activities with IC$\sub$50/ values of 28, 19 and 31, ${\mu}$M respectively. Compounds d and g also inhibited iron-dependent lipid peroxidation with IC$\sub$50/ values of 2.4 and 3.5 ${\mu}$M. In a primary rat cortical neuronal cell culture system, compounds b, d and g inhibited xanthine/xanthine oxidase-induced (IC$\sub$50/ values of 18.2, 2.1 and 54.6 ${\mu}$M) and H$_2$O$_2$-induced (IC$\sub$50/ values of 13.6, 1.9 and 25.7 ${\mu}$M) cytotoxicities. In addition, compounds d and g inhibited NMDA-induced excitotoxicity by 21 and 33%, and only compound d inhibited growth factor withdrawal-induced apoptosis by 31% at a tested concentration of 3 ${\mu}$M. The results suggest that the antioxidant constituents with in vitroneuroprotective activities may serve as lead chemicals for the development of neuroprotective agent.