• Journal of Ginseng Research
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• 제41권2호
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• pp.195-200
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• 2017

Background: The natural ratios of carbon (C), nitrogen (N), and sulfur (S) stable isotopes can be varied in some specific living organisms owing to various isotopic fractionation processes in nature. Therefore, the analysis of C, N, and S stable isotope ratios in ginseng can provide a feasible method for determining ginseng authenticity depending on the cultivation land and type of fertilizer. Methods: C, N, and S stable isotope composition in 6-yr-old ginseng roots (Jagyeongjong variety) was measured by isotope ratio mass spectrometry. Results: The type of cultivation land and organic fertilizers affected the C, N, and S stable isotope ratio in ginseng (p < 0.05). The ${\delta}^{15}N_{AIR}$ and ${\delta}^{34}S_{VCDT}$ values in ginseng roots more significantly discriminated the cultivation land and type of organic fertilizers in ginseng cultivation than the ${\delta}^{13}C_{VPDB}$ value. The combination of ${\delta}^{13}C_{VPDB}$, ${\delta}^{15}N_{AIR}$, or ${\delta}^{34}S_{VCDT}$ in ginseng, except the combination ${\delta}^{13}C_{VPDB}-^{34}S_{VCDT}$, showed a better discrimination depending on soil type or fertilizer type. Conclusion: This case study provides preliminary results about the variation of C, N, and S isotope composition in ginseng according to the cultivation soil type and organic fertilizer type. Hence, our findings are potentially applicable to evaluate ginseng authenticity depending on cultivation conditions.

• 한국농공학회지
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• 제43권4호
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• pp.120-128
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• 2001

Pollution sources and their environmental contributions were investigated to select the best management practices for the effective control of water quality. The nitrogen isotope mass ratio was determined to estimate the nitrate sources and their contribution. Sampling sites were chosen by calculating effluent loads at each watershed. Two liters each of the surface water samples were collected from four sites at Bokha river and two sites and Gwanri river. They were sequentially prepared through distillation method and analyzed using an isotope ratio mass spectrometer(IsoPrime EA). As revealed by the experimental values obtained the mass ratio values ($\delta$$^{5}$ N) of watersheds with a large amount of nonpoint sources were less than +5 an indication that the samples were influenced by chemical fertilizers. However watersheds with large amount of point sources were influenced not only by chemical fertilizers but also by animal and municipal wastes. The mass ratio values of samples generally decreased during rainy days. But during dry days the mass ratio values well-reflected the nitrate sources and the condition of watersheds. Through this study the nitrogen isotope mass ratio has been found to be useful for estimating nitrate sources and their contribution to the rural watersheds.

• 약학회지
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• 제53권5호
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• pp.293-297
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• 2009

The abuse of methamphetamine (MA) is one of the most serious drug abuses in Asia. And, the prevention of precursor production for abuse drug is one of the most effective drug control system. Isotope ratio analysis at natural abundance levels have been used to establish the environmental source or the geographic origin of various biological and nonbiological materials. Ephedrine, the precursor of MA, is produced by one of three methods; extraction from Ephedra plants, full chemical synthesis or via a semi-synthetic process involving the fermentation of sugar, followed by amination. We investigated the origin of ephedrine and pseudoephedrine based on the carbon and nitrogen values for nineteen pharmaceutical powder materials (PPMs) obtained from pharmaceutical company in Korea by stable isotope ratio mass spectrometry coupled to an elemental analyser (EA-IRMS). The carbon delta values for the ephedrine and pseudoephedrine were -24.21~-22.72 (mean=-23.72) $^{\cir}/_{\circ\circ}$ and -23.79~-22.71 (mean=-23.48) $^{\cir}/_{\circ\circ}$. The nitrogen delta values were 3.51~5.55 (4.43) $^{\cir}/_{\circ\circ}$ and 2.24~8.22 (5.42) $^{\cir}/_{\circ\circ}$. These results indicate that PPMs are semi-synthetic products. Therefore the origins of ephedrine(natural, semi-synthetic or synthetic) could be discriminated by using carbon and nitrogen stable isotope ratios. we are sure tat this stable isotope ratio analysis can discriminate the origins of precursors of methamphetamine.

• Applied Science and Convergence Technology
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• 제25권3호
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• pp.47-50
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• 2016

Low temperature test for half-wave resonator (HWR) cryomodule is performed at the superfluid helium temperature of 2 K. The effective temperature is defined for non-uniform temperature distribution. Helium leak detection techniques are introduced for cryogenic system. Experimental set up is shown to make the low temperature test for the HWR cryomodule. The cooldown procedure of the HWR cryomodule is shown from room temperature to 2 K. The cryomodules is precooled with liquid nitrogen and then liquid helium is supplied to the helium reservoirs and cavities. The pressure of cavity and chamber are monitored as a function of time. The vacuum pressure of the cryomodule is not increased at 2 K, which shows leak-tight in the superfluid helium environment. Static heat load is also measured for the cryomodule at 2.5 K.

• 분석과학
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• 제25권5호
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• pp.300-306
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• 2012

미라는 뼈, 머리카락, 피부, 손톱 등 서로 다른 시기를 반영하는 생체 조직분석이 가능하며, 이를 바탕으로 식생활, 환경 등 당시 생활상을 복원할 수 있는 매우 중요한 자료이다. 본 연구에서는 문경 흥덕동 회곽묘에서 출토된 조선시대 미라에서 추출한 뼈 콜라겐과 머리카락 케라틴의 탄소와 질소 안정동위원소 분석을 수행하였으며, 국내 출토 미라에 안정동위원소 분석을 적용한 첫 사례이다. 우리가 섭취하는 식료의 종류에 따라 뼈와 머리카락 등 인체 조직에는 그 특유의 탄소와 질소 안정동위원소 정보가 기록되며, 그 비율은 시간이 경과하여도 변하지 않는 것으로 알려져 있다. 특히 뼈에서 추출된 콜라겐이라는 단백질은 생애 전주기의 평균 식생활을 추적할 수 있으며, 머리카락의 케라틴의 경우 길이에 따라 죽기 전 몇 달에서 몇 년의 식생활 정보를 담고 있다. 미라 조직의 안정동위원소 분석 결과 그 평균값은 다음과 같다(뼈 콜라겐(${\delta}^{13}C$=-19.0‰, ${\delta}^{15}N$=11.4‰), 머리카락 케라틴(${\delta}^{13}C$=-21.3‰, ${\delta}^{15}N$=14.3‰). 탄소 안정동위원소 값으로부터 생애 주기 동안 주로 $C_3$ 작물 위주의 식생활을 하였다는 것을 예측할 수 있었으며, 특히 질소 안정동위원소 값의 경우 머리카락의 값이 뼈 콜라겐의 값보다 2.9‰ 높게 나타난 것으로 미루어 볼 때 생애 전반에 걸친 영양 상태보다 죽기 전 몇 달 동안 육류 섭취 등으로 인한 단백질 섭취량이 높았다는 것을 추정할 수 있었다.

• Animal cells and systems
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• 제14권4호
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• pp.297-303
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• 2010

To document the basic ecological aspects of Chaoborus species, which has never been reported in Korea, we attempted to identify the species, to monitor seasonal and vertical dynamics, and to elucidate trophic relations of the species in Sang-Chun reservoir. Using morphological characteristics, we identified the collected samples as C. flavicans. Also, we compared the distribution of C. flavicans, Daphnia rosea and chlorophyll a to observed seasonal dynamics. The increase of C. flavicans was observed 1-2 weeks after the increase of D. rosea. Survey of diel vertica migration patterns in the summer season showed that C. flavicans were in hypolimnion at daytime, but moved to the epilimnion at night. Finally, to determine trophic relationships in Sang-Chun reservoir, additional studies on the food web were undertaken by stable isotope analysis. Chaoborus flavicans I-II instars appear to be filter feeders based on carbon isotope values. Trophic levels of C. flavicans III-IV instars were shown to be higher than other zooplankto based on nitrogen isotope values.

• Journal of Animal Science and Technology
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• 제47권3호
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• pp.481-490
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• 2005

Nitrate contamination in water system is a critical environmental problem caused by excessive application of chemical fertilizer and concentration of livestock. In order to prevent further contamination, therefore, it is necessary to understand the origin of nitrate in nitrogen loading sources and manage the very source of contamination. The objective of this study was to examine the nitrate contamination sources in different agricultural system by using nitrogen isotope ratios. Groundwater and runoff water samples were collected on a monthly basis from February 2003 to November 2003 and analyzed for nitrogen isotopes. The nitrate concentrations of groundwater in livestock fanning area were higher than those in conventional and organic fanning area and exceeded the national drinking water standard of 10mg N/ l. The ${\delta}^{15}N$ranges of chemical fertilizer and animal manure were - 3.7${\sim}$+2.3$\textperthousand$ and +12.5${\sim}$26.7$\textperthousand$, respectively. The higher ${\delta}^{15}N$ of animal manure than those of chemical fertilizer reflected isotope fractionation and volatilization of '''N. The different agricultural systems and corresponding average nitrate concentrations and ${\delta}^{15}N$ values were: conventional farming, 5.47mg/e, 8.3$\textperthousand$; organic fanning, 5.88mg/e, 10.1$\textperthousand$; crop-livestock farming, 12.5mg/e, 17.7%0. These data indicated that whether conventional or organic agriculture effected groundwater and runoff water quality. In conclusions, relationship between nitrate concentrations and ${\delta}^{15}N$ value could be used to make a distinction between nitrate derived from chemical fertilizer and from animal manure. Additional investigation is required to monitor long-term impact on water quality in accordance with agricultural systems.

• 환경생물
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• 제27권3호
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• pp.279-284
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• 2009

In order to understand food sources-metabolism for the pacific oyster (Crassostrea gigas), the stable isotope ratios of carbon (${\delta}^{13}C$) and nitrogen (${\delta}^{15}N$) of its gut, gill, and muscle as well as potential food sources (particulate organic matter, sedimentary organic matter, benthic microalgae, seagrass detritus) were determined in Dongdae Bay. Average ${\delta}^{13}C$ and ${\delta}^{15}N$ values reflect that oysters primarily fed on sedimentary organic matter as opposed to suspended organic matter during summer and winter seasons. However, the relatively enriched $^{15}N$ values of particulate organic matter (>$250{\mu}m$) and sedimentary organic matter in the summer may be due to the photosynthetic incorporation of $^{15}N$-enriched nitrogen (DIN) or the spawning events of bivalves. Specific oyster tissues (gut, gill, and muscle) revealed different metabolic pathways, which were determined through analysis of ${\delta}^{13}C$ and ${\delta}^{15}N$ in each organ. The present results suggest the determination of carbon and nitrogen stable isotopes to be a useful approach in ecological research related to the food sources- metabolism of Crassostrea gigas.

• 한국유기농업학회지
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• 제19권spc호
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• pp.161-164
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• 2011

Nitrogen fixation by legumes can be valuable sources for organic farming. This study was to investigate the effect of different legume mixtures on nitrogen fixation and transfer to grasses on spring paddy field. Three different mixtures were used (rye+hairy vetch, Italian ryegrass+crimson clover, oat+pea) in a randomized complete block design with three replications and sowed in pots with different sowing rate (5:5 rye:hairy vetch,7:3=Italian:crimson, 6:4=oat:pea) on early March. $(^{15}NH_4)SO_4$ solution at. 99.8 atom%$^{15}N$ was applied to the each pot at the rate of 2kg N $ha^{-1}$ on $16^{th}$ April. Forage were harvested at ground level in heading stage and separated into legume and grass. Total N content and $^{15}N$ value were determined using a continuous flow stable isotope ratio mass spectrometry. DM yield of rye+vetch, Italian+crimson and oat+pea were 6,607, 3,213 and 4,312kg/ha, respectively. Proportion of N from fixation was 0.73(rye+vetch), 0.42(Italian+crimson) and 0.93(oat+pea). The percentages of N transfer from legume to grass were from 61% to 24% in different method by treatments and -35% to 21% in isotope dilution method.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.777-782
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• 1999

It has been acknowledged that fertilizer and animal waste have different ratio of \ulcornerN/\ulcornerN which is presented as a symbol of $\delta$\ulcornerN, and that the values of $\delta$\ulcornerN for fertilizer and animal waste are placed less than +8 $\textperthousand$ and higher than +10$\textperthousand$, respectively. By this reason, the demarcation range for the source nitrogen mass ratio is between +8$\textperthousand$ and +10$\textperthousand$. In this study, we would suggest a possible method to trace the major pollution basis using the nitrogen isotope analysis method for management of water quality.