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Monitoring of the Content of Imidazoline-Containing Corrosion Inhibitor

  • Zadorozhny, P.A.;Sukhoverkhov, S.V.;Markin, A.N.;Savin, K.I.;Prokuda, N.A.
    • Corrosion Science and Technology
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    • v.16 no.4
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    • pp.161-166
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    • 2017
  • The qualitative composition of active components of the corrosion inhibitor CGW-85567 was studied. It was found that С18:2 and С18:1 imidazolines and the corresponding imidazolin-amides are the major components. The HPLC/MS technique was developed for their determination in the water solutions of monoethylene glycol (MEG). Industrial application of the inhibitor showed that MEG solution retained high concentration of the inhibitor for a long time after ceasing its addition into pipelines. Low values of the partition coefficients (0.010-0.014) of imidazolines in the system "water solution of MEG (concentration of MEG 62-85% v/v) - gas condensate" have allowed to pass on from the technology of continuous pumping of the inhibitor into protected pipelines to the periodic dosing technology. Taking into account a long time of circulation in the system and high temperatures during MEG regeneration process possible degradation products of the inhibitor were studied. N, N-dimethyl-dodecanamine-1, and N, N-dimethyl-tetradecanamine-1 were identified as major degradation products of the corrosion inhibitor CGW-85567.

The Improvement in Signal Integrity of FT-ICR MS (FT-ICR 질량분석기의 신호 충실성 향상)

  • Kim, Seung-Yong;Kim, Seok-Yoon;Kim, Hyun Sik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.1
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    • pp.201-204
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    • 2011
  • For efficient noise reduction in a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrum, a new algorithm was proposed. The suggested algorithm reduces white and electrical noise, and it improves signal-to-noise ratio. This algorithm has been optimized to reduce the noise more efficiently using the traces of signal level. The algorithm has been efficiently combined with derivative window to improve the resolution as well S/N. Time domain data was corrected for DC voltage interference. $t^n$ window was applied in time domain data to improved the resolution. However, $t^n$ window can improve the signal resolution, it will also increase the noise level in frequency domain. Therefore, newly developed noise reduction algorithm will be applied to make a balance between resolving power and S/N ratio for magnitude mode. The trace algorithm can determine the current data point with several data points (mean, past data, calculated past data). In the current calculations, we assumed data points with S/N ratio more than 3 were considered as signal data points. After the windowing and noise reduction, both resolution and signal-to-noise ratio were improved. This algorithm is applicable more efficiently to frequency dependent noise and large size data.

Synthesis of Methylated Anthranilate Derivatives Using Engineered Strains of Escherichia coli

  • Lee, Hye Lim;Kim, Song-Yi;Kim, Eun Ji;Han, Da Ye;Kim, Bong-Gyu;Ahn, Joong-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.29 no.6
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    • pp.839-844
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    • 2019
  • Anthranilate derivatives have been used as flavoring and fragrant agents for a long time. Recently, these compounds are gaining attention due to new biological functions including antinociceptive and analgesic activities. Three anthranilate derivatives, N-methylanthranilate, methyl anthranilate, and methyl N-methylanthranilate were synthesized using metabolically engineered stains of Escherichia coli. NMT encoding N-methyltransferase from Ruta graveolens, AMAT encoding anthraniloyl-coenzyme A (CoA):methanol acyltransferase from Vitis labrusca, and pqsA encoding anthranilate coenzyme A ligase from Pseudomonas aeruginosa were cloned and E. coli strains harboring these genes were used to synthesize the three desired compounds. E. coli mutants (metJ, trpD, tyrR mutants), which provide more anthranilate and/or S-adenosyl methionine, were used to increase the production of the synthesized compounds. MS/MS analysis was used to determine the structure of the products. Approximately, $185.3{\mu}M$ N-methylanthranilate and $95.2{\mu}M$ methyl N-methylanthranilate were synthesized. This is the first report about the synthesis of anthranilate derivatives in E. coli.

Optimal Culture Conditions for in vitro Propagation of Orostachys japonicus and Enhancement of Polysaccharide Production

  • Kim, Won-Jung;Kang, Young-Min;Park, Dong-Jin;Huh, Gyung-Hye;Lee, Byung-Hyun;Choi, Myung-Suk
    • Korean Journal of Medicinal Crop Science
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    • v.12 no.2
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    • pp.129-134
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    • 2004
  • Optimal culture conditions for efficient in vitro propagation and polysaccharide production of Orostachys japonicus were established. The highest growth yield was achieved in 1/2 MS medium, while the lowest growth yield was obtained in 4 MS medium. The patterns of polysaccharide formation were a little similar in all cases, but on MB5 medium, the po]ysaccharide contents of plant were higher than others. Among the modified nitrate levels, effective growth level were obtained in 1/4 N and 1/2 N. High contents of polysaccharide were obtained in 4 N. Different concentration of potassium and calcium did not improve the growth and polysaccharide production. The micropropagated shoots were successfully acclimatized artificial soils.

Cytotoxic Chemical Constituents from the Mushroom of Pholiota adiposa

  • Chung, Ill-Min;Kong, Won-Sik;Lee, Oh-Kyu;Park, Jeong-Sik;Ahmad, Ateeque
    • Food Science and Biotechnology
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    • v.14 no.2
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    • pp.255-258
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    • 2005
  • The compounds, 1-Linoleic-2-olein (1), stigmasterol (2), 1,4-glucopyranosyl-1',4'-glucopyranosyl-1",4"-glucopyranoside (3), 2',3'-diphosphoryl-1'-propanoxy-${\beta}$-D-glucopyranoside (4), 1-Linoleic-3-olein (5), l-(N,N,N-trimethyl ethyl amino phosphoryl)-2,3-dilinolein ion (6) and glyceryl phosphate (7) were isolated and identified from the Mushroom of Pholiota adiposa for the first time by column chromatography, TLC, UV, IR, $^1H$ and $^{13}C$ NMR, EI-MS, and FAB-MS. The compounds 1 and 2 were found to have weak cytotoxicity against P388 murine leukemia cells. However, the compounds 6 and 7 did not show any cytotoxicity.

재래흑돼지육의 진공포장 숙성중 지방산 조성과 SPME-GC/MS에 의한 향기성분 분석

  • Gang, Seon-Mun;Kim, Yong-Seon;Lee, Seong-Gi
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2005.10a
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    • pp.234-239
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    • 2005
  • 본 연구는 재래흑돼지육의 진공포장 숙성중 지방산 조성과 SPME-GC/MS에 의한 향기성분을 구명하고자 실시하였다. 지방산 조성으로 C14:0, C16:1n7은 재래흑돼지육이 개량종 돼지육보다 낮았으며(p<0.05), C18:1n7, C22:4n6는 재래흑돼지육이 높았다(p<0.05). 숙성기간 동안 향기성분은 숙성 0일에 2-decanone, 2-ethyl hexanol, hexa -noic acid가 재래흑돼지육에서만 검출되었으며, 숙성 6, 12일에는 butanoic acid, 2.3-butanediol, benzen -acetaldehyde, benzeneethanol, 2-hexadecal, hexanoic acid가 재래흑돼지육에서만 검출되었다.

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Methane Emission, Nutrient Digestibility, Energy Metabolism and Blood Metabolites in Dairy Cows Fed Silages with and without Galacto-oligosaccharides Supplementation

  • Santoso, B.;Kume, S.;Nonaka, K.;Kimura, K.;Mizukoshi, H.;Gamo, Y.;Takahashi, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.4
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    • pp.534-540
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    • 2003
  • This study was conducted to investigate the effect of supplementation of galacto-oligosaccharides (GOS) on methane emission, nutrient digestibility, energy utilization and blood metabolites by Holstein cows fed silages. In two sequential digestion and respiratory trials, two non-lactating Holstein cows were arranged to a balanced incomplete block design. Experimental diets consisted of two silage types; orchardgrass (Dactylis glomerata L.) based silage (OS), mixed silage (orchardgrass based silage and alfalfa (Medicago sativa L.) silage) (MS), while two GOS levels were without supplementation (0) and 2% of dry matter intake supplementation (2). Four combination diets were OS-0, OS-2, MS-0 and MS-2. Significant effects of silage types and GOS supplementation levels were not observed for DM and OM intake. Whereas the digestibility of OM, NDF and ADF was significantly (p<0.05) higher in cows fed OS with and without GOS compared cows fed MS diets. As percentage of GE intake, fecal energy loss for OS diets was significantly (p<0.05) declined than for MS diets. In contrast, cows fed MS diets had lower (p<0.05) urine energy loss as a proportion of GE intake compared to OS diets. Energy loss as CH4 and heat production was numerically increased when cows fed both OS and MS with GOS supplementation. Compared to OS, CH4 emission in cows fed MS was numerically decreased by 10.8 %. Methane conversion ratio (energy loss as CH4 per unit of GE intake) for OS-0, OS-2, MS-0 and MS-2 were 7.1, 7.2, 6.8 and 7.0, respectively. Plasma of glucose and urea-N concentration were significantly (p<0.05) elevated from 1 h to 6 h after feeding, otherwise total protein in plasma was declined (p<0.01) at 6 after feeding.

Analysis of Heterocyclic Amines in Mainstream Cigarette Smoke using by LC-MS/MS (LC-MS/MS를 이용한 담배 연기 중 Heterocyclic Amines의 분석)

  • Kim, Ick-Joong;Jang, Gi-Chul;Ji, Sang-Un;Min, Hye-Jeong;Kim, Hyo-Keun;Hwang, Geon-Jung
    • Journal of the Korean Society of Tobacco Science
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    • v.30 no.1
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    • pp.33-38
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    • 2008
  • This study was carried out to determine the analytical methods for heterocyclic amines(HAs) of the tobacco smoke by LC/MS/MS. HAs have been found in pyrolysate of protein and cooked food including protein, were known the Sugimura compound. HAs content of the smoke were known to exist very low ppb level. Especially, some of HAs are mutagenic and carcinogenic compounds. In according to IARC, the toxicity of N-heterocyclic amines classified IARC class 2A or 2B group. Precursors of these compounds are glutamic acid, protein and free amino acids including tryptophan, therefore, the precursors have been proved in cooked food continuously. This study was investigate multiple analysis methods for HAs and HAs contents of some commercial products. In this study, we used the linear type smoking machine for HAs analysis. At the ISO conditions, mainstream smoke was collected on cambridge filter pad, and then cambridge filter pad was extracted by 0.1% acetic acid. The extracted solution were passed cation exchange SPE cartridge to remove matrix, samples were analyzed using LC/MS/MS on MRM mode. From the result that optimized this methods, the correlation coefficient(R) of the individual compounds were good linearity over 0.999, recovery rate over 96% and the limit of detection were good values between 0.06 to 0.37 ng/mL, In addition, HAs content of some commercial products were in range of 0.02 to 43.8 ng/cig.

Determination of 8-iso-PGF as Oxidative Stress Marker in Human Urine by High Performance Liquid Chromatography with Tandem Mass Spectrometry (LC/MS/MS를 이용한 산화성 스트레스 지표로써 소변 중 8-iso-PGF 분석)

  • Kho, Young-Lim;Lee, Eun-Hee;Chae, Hong-Jae;Choi, Kyung-Ho;Paik, Do-Myung
    • Journal of Environmental Health Sciences
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    • v.36 no.1
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    • pp.44-51
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    • 2010
  • This study aimed to develop analytical method for 8-isoprostanes as biomarkers for oxidative stress with LC/MS/MS technique and to apply the method for human urine samples. Analyzed compounds for urinary oxidative stress markers were 7 stereo-isomers of prostaglandins and the internal standard (iso-$PGF_{2{\alpha}}-d_4$) was used to adjust the recovery rate. The method for determining urinary iso-$PGF_{2{\alpha}}$ consisted of solid phase extraction and LC/MS/MS detection. Separation of isomers of prostaglandins completed by porous graphitic carbon column and buffer solution. Detection limits for urinary markers of oxidative stress, iso-$PGF_{2{\alpha}}$ with LC/MS/MS were 0.01 ng/ml by S/N ratio 3 and 0.028 ng/ml by calculated as to FDA method. The recovery (92.8~101.9%) and precision (8.8~20.7%) of analysis were feasible for detecting iso-$PGF_{2{\alpha}}$ in real human urine samples. We detected 4 isomers of prostaglandins in human urine samples. Mean (standard deviation) of urinary iso-$PGF_{2{\alpha}}$ concentration were 0.231 (0.117) ng/mg creatinine for smoking group and 0.154 (0.082) ng/mg creatinine for non-smoking group.

Modelling of effluent and GHGs for wastewater treatment plants using by MS Excel simulator(PKES) (MS Excel 시뮬레이터(PKES)를 이용한 하수처리장 유출수 및 온실가스 모델링)

  • Bin, Jung-In;Lee, Byung-Hun
    • Journal of Korean Society of Water and Wastewater
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    • v.28 no.6
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    • pp.735-745
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    • 2014
  • This paper presents PKES(PuKyung -Excel based Simulator) for WWTPs(wastewater treatment plants) by using MS Excel and VBA(Visual Basic for Application). PKES is a user-friendly simulator for the design and optimization of the whole plant including biological and physico-chemical processes for the wastewater and sludge treatment. PKES calculates the performance under steady or dynamic state and allows changing the mathematical model by the user. Mathematical model implemented in PKES is a improved integration model based on ASM2d and ADM1 for simulation of AS(activated sludge) and AD(anaerobic digestion). Gaseous components of $N_2$, $N_2O$, $CO_2$ and $CH_4$ are added for estimation of GHGs(greenhouse gases) emission. The simulation results for comparison between PKES and Aquasim(EAWAG) showed about the same effluent concentrations. As a result of verification using by measured data of BOD, TSS, TN and TP for 2 years of operation, calculated effluent concentrations were similar to measured effluent concentrations. The values of average RMSE(root mean square error) were 1.9, 0.8, 1.6 and 0.2 mg/L for BOD, TSS, TN and TP, respectively. Total GHGs emission of WWTP calculated by PKES was 138.5 ton-$CO_2$/day and GHGs emissions of $N_2O$, $CO_2$ and $CH_4$ were calculated at 21.7, 28.9 and 87.9 ton-$CO_2$/day, respectively. GHGs emission of activated sludge was 32.5 % and that of anaerobic digestion was 67.5 %.