• 한국물환경학회지
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• 제23권1호
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• pp.33-37
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• 2007

Microelectrodes for measuring nitrogenous compounds (${NH_4}^+$, ${NO_3}^-$) that were applied into the microfluidics chips was investigated, and the effect of temperature was especially examined. In this specific research, microelectrodes were first calibrated to check the function, and then microsensor that was combined microelectrode with microfluidic chip was re-calibrated. Experimental results showed that there are no change in the function between microelectrode and microfluidic chip. The electro motive force (EMF) for the ${NH_4}^+$ microsensor was similar to the one theoretically calculated from Nernst equation, but the EMF for ${NO_3}^-$ showed minor change.

• 천문학회보
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• 제36권2호
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• pp.82.1-82.1
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• 2011

Korea Astronomy and Space Science Institute (KASI) operates 2 solar radio observing facilities, e-CALLISTO (Earthwide network of Compound Astronomical Low-cost Low-frequency Instrument for Transportable Observatory) station and Korean Solar Radio Burst Locator (KSRBL). Although e-CALLISTO tracking system improvement.is underway, at least 6 new events were observed in this year. Software development for KSRBL is in progress. The antenna calibration software was updated and flux calibration software was developed. Also the automatic daily overview spectrum monitoring system is now operational. We found solutions to several problems including spurious data and FPGA board communication. However, a few minor unsolved hardware problems still persist. Meanwhile, at least 6 new events were observed by KSRBL in this year, and a comparative study with HXR is currently underway.

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.547-552
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• 2007

This study examined the thermal reactions of 2,4-dibromophenol (diBP), 2,6-diBP and 2,4,6-triBP. The products obtained under pyrolytic conditions were analyzed by gas chromatography/mass spectrometry (GC/MS). 2,7-dibromodibenzo-p-dioxin (diBDD) was the major compound produced from the thermal reaction of 2,4-diBP. In addition, monoBDD and triBDDs were obtained through a process of debromination and bromination, respectively. The pyrolysis of 2,6-diBP and 2,4,6-triBP produced two major brominated dioxin isomers through direct condensation and a Smiles rearrangement. The two ortho-Brs in 2,6-diBP and 2,4,6-triBP mainly led to the production of dioxins, whereas in addition to 2,7-diBDD, 2,4-diBP produced two furans as minor products, 2,8-dibromodibenzofuran (diBDF) and 2,4,8-triBDF, through the intermediate dihydroxybiphenyl (DOHB). The maximum yield of the major dioxins was obtained at 400 oC, and decomposition by debromination at 500 oC resulted in less substituted bromodioxins.

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.97-102
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• 1999

Antimicrobial activity and chemical composition of volatile flavor extracts from Agastache rugosa were investigated. The volatile flavor extracts were obtained from leaves and stems of Agastache rugosa by simultaneous distillation extraction (SDE) method. Antimicrobial activity was investigated by disc diffusion and broth dilution methods against several microorganisms of Bacillus cereus, bacillus megaterium, Bacillus subtilis, Corynebacterium xerosis, Staphylo coccus aureus, Staphylococcus epidermidis, Agrobacterium rhizogenes , Agrobacterium tumefaciences, Enterobacter cloacae, Escherichia coli, Salmonella typhi, Vibrio parahaemolyticus, Candida utilis and Saccharomyces cerevisiae. Volatile flavor extractsfrom leaves have strong antimicrobial activity against C.utilis and S.cerevisiae. When 0.12% volatile flavor extracts from fresh leaves were included in the medium, lag phase of C. utilis was extended 6 hr and that of S.utilis and S.cerevisiae was extended 2hr. Further analyses were performed to elucidatethe effective component of the extracts. The major component of volatile flavor was estragole, a phenolic compound. Minor components were determined to be terpenes , alcohols, acids , esters, ketones and aldethydes.

• 자원리싸이클링
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• 제1권1호
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• pp.51-57
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• 1992

동전해 과정중 비소를 제거하는 과정에서 생성된 함비소 동슬라임으로부터 비소의 희수와 고순도 비소의 제조를 위한 기초적인 자료를 얻기 위하여 함비소 슬라임의 염산침출실험을 행하였다. 함비소 슬라임은 Cu와 As의 금속간화합물인 $\beta-Cu_3As$가 주이며, 그밖에 미량의 $CU_2O$dhkCusAs가 혼재되어 있었다. 함비소 슬라임의 최적 염산침출조건은 슬라임입도 -140 mesh, 반응온도 $60^{\circ}C$ 염산과 슬라임의 비 3:1, 산소유량 1.25l/min, 침출반응시간 150분이었으며, 위의 침출실험조건에서 비소의 최대 침출들은 98%이었다.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2001년도 정기총회 및 봄 학술발표회 초록집
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• pp.238-239
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• 2001

The egg-yolk precursor vitellogenin(VTG) is secreted by the liver of female and male fish, in response to estrogenic compound. Carp(Cryprinus carpio) vitellogenin of one major protein is 160kDa, two minor proteins is 110kDa and 170kDa. We were induced vitellogenin by inject of 17-estradiol and purified in a two step procedure by separating it from plasma protein precipitated by 35% saturated ${(NH_4)}_2SO_4$ and then from the remainder by Mono-Q chromatography. We found major carp(Cyprinus carpio) vitellogenin band at 160kDa. Effect of different concentration of oestrogen on vitellogenin synthesis in carp(Cyprinus carpio) exposed for 4 weeks. Show differential effects on vitellogenin synthesis 7 days after treatment. Plasma vitellogenin was measured 3 times for each by an enzyme linked immunosorbent assay(ELISA). ELISA was developed for the detection of the egg yolk precursor vitellogenin in plasma of carp(Cyprinus carpio). The ELISAS performance was optimized and characterized.

• 식품과학과 산업
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• 제51권2호
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• pp.127-135
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• 2018

지방산화는 기본적으로 불포화지방과 산소의 결합이나 이 현상을 제대로 알고 실제 식품에 적용하기 위해서는 지방산화에 미치는 모든 인자들의 화학적 관점(one-electron reduction potential, bond dissociation enthalpy) 뿐만 아니라 물리적 현상(interface, antioxidant polar paradox)을 포괄적으로 이해해야 한다. Invitro실험법에 의해 도출된 산화방지제는 가능성을 보여주는 것이나 실제 식품과 bulk oil, 유화형태, 오르가노젤과 같은고체 상태의 다양한 매트릭스에서는 다른 활성을 나타낸다. 또한 산화방지제의 농도와 다른 물질의 존재에 따라 예상과 다른 활성을 나타내기도 한다. 산화방지제를 활용하여 최종제품의 유통기한을 증가시키기 위해서는 실제 활용될 제품의 매질로 사용해야 한다.

• Journal of Ginseng Research
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• 제43권3호
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• pp.460-474
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• 2019

Background: Ginsenoside compound K (CK) is a promising drug candidate for rheumatoid arthritis. This study examined the impact of polymorphisms in NR1I2, adenosine triphosphate-binding cassette (ABC) transporter genes on the pharmacokinetics of CK in healthy Chinese individuals. Methods: Forty-two targeted variants in seven genes were genotyped in 54 participants using Sequenom MassARRAY system to investigate their association with major pharmacokinetic parameters of CK and its metabolite 20(S)-protopanaxadiol (PPD). Subsequently, molecular docking was simulated using the AutoDock Vina program. Results: ABCC4 rs1751034 TT and rs1189437 TT were associated with increased exposure of CK and decreased exposure of 20(S)-PPD, whereas CFTR rs4148688 heterozygous carriers had the lowest maximum concentration ($C_{max}$) of CK. The area under the curve from zero to the time of the last quantifiable concentration ($AUC_{last}$) of CK was decreased in NR1I2 rs1464602 and rs2472682 homozygous carriers, while $C_{max}$ was significantly reduced only in rs2472682. ABCC4 rs1151471 and CFTR rs2283054 influenced the pharmacokinetics of 20(S)-PPD. In addition, several variations in ABCC2, ABCC4, CFTR, and NR1I2 had minor effects on the pharmacokinetics of CK. Quality of the best homology model of multidrug resistance protein 4 (MRP4) was assessed, and the ligand interaction plot showed the mode of interaction of CK with different MRP4 residues. Conlusion: ABCC4 rs1751034 and rs1189437 affected the pharmacokinetics of both CK and 20(S)-PPD. NR1I2 rs1464602 and rs2472682 were only associated with the pharmacokinetics of CK. Thus, these hereditary variances could partly explain the interindividual differences in the pharmacokinetics of CK.

• 대한핵의학회지
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• 제29권1호
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• pp.110-117
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• 1995

Tc-99m Labeled hexamethylenepropyleneamineoxime ([$^{99m}Tc$]-HMPAO) is a famous amino-oxime compound and is widely used to construct SPECT images of cerebral blood flow. To investigate the relationship between chemical structure and radiolabeling in these kind of diamine-oxime compounds, we synthesized seven compounds by Schiff's base formation and successive reduction with sodium borohydride. They were (RR/SS )-4,8-diaza-3,6,6,9-tetramethylundecane-2,10-dione bisoxime (2), (RR/SS/meso)-4,8-diaza-3,9-dimethy-lundecane-2,10-dione bisoxime (4), (RR/SS/meso)-4,8-diaza-3,10-dimethyldodecane-2,11-dione bisoxime (5), (RR/SS/meso)-4,7-diaza-3,6,6,8-tetramethyldecane-2,9-dione bisoxime (8), (RR/SS/meso)-4,7-diaza-5,6-cyclohexyl-3,8-dimethyldecane-2,9-dione bisoxime (10), (RR/SS/meso)-3,4-bis(1-aza-2-methyl-3-oxime-1-butyl)-benzoic acid (12), and (RR/SS/ meso)-2,3-bis(1-aza-2-methyl-3-oxime-1-butyl) benzophenone (14). Chemical structures of all the synthesized compounds were identified by taking $^1H$ spectrum. Among them, 2 and 4 are propyleneamine oxime (PnAO), 6 is butyleneamine oxime (BnAO) and 8, 10, 12 and 14 are ethyleneamine oxime (EnAO). Each compound (0.5 mg) was incubated with stannous chloride (0.5 g - 8 g), carbonate-bicarbonate buffer (final concentration = 0.1 M, pH 7 - pH 10) and Tc-99m-pertechenate (1 ml). Tc-99m labeling of these compounds were checked by ITLC (acetone), ITLC (normal saline), reverse phase TLC (50 % acetonitrile) and ITLC (ethyl acetate). According to the results, EnAO's were not labeled by Tc-99m in any of above condition. About 11 % of maximum labeling efficiency was obtained with BnAO. However, 4 (PnAO) was labeled with Tc-99m to 85 % which is similar to the labeling efficiency of 2 (HMPAO). Hydrophilic impurity (9 % ) was the most significant problem with the labeling of 4, however, pertechnetate (3 % ) and colloid (3 %) were minor problem. In conclusion, we synthesized seven diamine blsoxlme compounds. Among them, four EnAO compounds were not labeled by Tc-99m. A BnAO was labeled poorly and two PnAO's were labeled well. These labeling can be explained by tertiary structure of their Tc-99m chelate.

• 한국환경농학회지
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• 제22권1호
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• pp.36-40
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• 2003

토양혼화실험을 통한 초장의 신장 억제를 조사한 결과 초장이 50% 억제되었을 때의 cyclosulfamuron의 농도를 품종별로 비교하여 보면 동진벼, 화성벼, 일품벼의 경우 각각 6.3, 9.2 146.8 mg/kg으로 동진벼가 제초제 cyclosulfamuron에 가장 민감하게 지상부의 생육이 억제되었다. 또한 cyclosulfamuron은 동일한 농도에서 지상부보다는 지하부의 생육을 더 크게 억제하였으며, 0.3mg/kg 처리 수준에서 동진벼의 경우 건물중의 억제정도는 지상부가 4.8% 정도이었으나 지하부는 38.9%이었다. 벼의 acetolactae synthase 활성을 cyclosulfamuron의 농도별로 검정한 결과 공시된 품종간에 큰 차이가 없었으며 50% 억제되는 농도는 화성벼, 동진벼 및 일품벼의 경우 각각 42.7, 32.7 및 $56.7\;{\mu}M$이었다.