• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 하계학술대회 논문집
• /
• pp.240-243
• /
• 2002

Carbon nitride films have been deposited on Si(100) substrate by a high voltage discharge plasma combined with laser ablation in a nitrogen atmosphere. The films were grown both with and without the Presence of an assisting focused Nd:YAG laser ablation. The laser ablation of the graphite target leads to vapor Plume plasma expending into the ambient nitrogen arc discharge area. X-ray photoelectron spectroscopy and Auger electron spectroscopy were used to identify the binding structure and the content of the nitrogen species in the deposited films. The surface morphology of the films was studied using a scanning electron microscopy Data of infrared spectroscopy and x-ray photoelectron spectroscopy indicate the existence of carbon-nitrogen bonds in the films. The x-ray diffraction measurements have also been taken to characterize the crystal properties of the obtain films.

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
• /
• pp.65-70
• /
• 2005

A growing body of evidence shows that nitric oxide $({\cdot}NO)$ and ${\cdot}NO-derived$ reactive nitrogen species (RNS) act as both plant physiological regulators and stressors. However, very little is known concerning metabolism of RNS in plant cells. In this paper, we explore a plant metabolic basis for RNS, with special emphasis on the possible relationship to nitrogen assimilation, and discuss the potential of the metabolic engineering for plant-biotechnological application.

• 한국대기환경학회:학술대회논문집
• /
• 한국대기환경학회 1994년도 제19회 추계 대기보전학술대회 요지집
• /
• pp.17-20
• /
• 1994

• 한국환경복원기술학회지
• /
• 제4권3호
• /
• pp.19-29
• /
• 2001

This study was carried out to examine the recovery of forest ecosystem at the burned areas of coniferous (Mt. Chosdae) and broad leaved forest (Samsinbong in Mt. Chiri) by investigating the changes of forest vegetation. The results obtained are summarized as follows; 1. In the Samsinbong, the total number of species appeared at the burned area were 5 species at tree layer, 11 species at sub-tree layer and 24 species at herb layer, and at the unburned area were 5 species at tree layer, 14 species at sub-tree layer, 18 species at shrub layer and 23 species at herb layer, respectively. In the Mt. Chosdae, the total number of species appeared at the burned area only showed to 83 species at herb layer, and at the unburned area were 7 species at tree layer, 13 species at sub-tree layer, 21 species at shrub layer and 46 species at herb layer, respectively. 2. In the soil chemical properties of the burned area of Samsinbong, pH was 5.8, and contents of Organic matter, Total nitrogen, Available $P_2O_5$, Exchangeable $K^+$, Exchange $Ca^{{+}{+}}$ and Exchange $Mg^{{+}{+}}$ were 7.42%, 0.73%, 28.5mg/kg, 1.3me/100g, 13.3me/100g and 2.2me/100g, respectively. But they showed a tendency to decrease by passing the time. In the soil chemical properties of the burned area of Mt. Chosdae, pH was 5.3, and contents of Organic matter, Total nitrogen, Available $P_2O_5$, Exchangeable $K^+$, Exchange $Ca^{{+}{+}}$ and Exchange $Mg^{{+}{+}}$ were 6.42%, 0.25%, 24.4mg/kg, 0.7me/100g, 3.7me/100g and 2.1me/100g, respectively, and they also showed a tendency to decrease by passing the time. 3. An the burned and unburned areas of Samsinbong, the total evolved amounts of soil respiration were $4,049.1mg/m^2/h$ and $9,950.0mg/m^2/h$, respectively. An the burned and unburned areas of Mt. Chosdae, the total evolved amounts of soil respiration were $4,392.4mg/m^2/h$ and $8,286.5mg/m^2/h$, respectively.

• 한국균학회지
• /
• 제21권3호
• /
• pp.235-245
• /
• 1993

The symbiotic properties of arbuscular mycorrhizal fungi(AMF) such as the absence and/or presence of symbiosis, spore density, and six factors of phycochemical properties of soil were investigated in the rhizosphere of seven sand dune plants and three control plants around Kum river. The infection of AMF was confirmed in all plants. Three genera, nine species of the AMF spores were identified in the sand dune; Ac. scrobiculata, G. aggregatum, G. convolutum, G. diaphanum, G. dimophicum, G. geosporum, G. vesiculiferum, G. tortuosum, S. pachycaulis. All of them were also found in the control, but S. pachycaulis were only separated in the sand dune. In the control, three genera, four species were identified; G. flavisporum, Gi. margarita, Sc. gregaria. Sc. persica. The species specificity was not found between the sand dune plant and AMF. However, the AMF was thought to be correlated with the soil factors. The spore density was stimulated with increase of the organic matter and the nitrogen content, but inhibited with the water content and the phosphorus content. In respect of the seasonal factor, the spore density was increased in the late growth period of plants.

• Fisheries and Aquatic Sciences
• /
• 제21권8호
• /
• pp.28.1-28.12
• /
• 2018

Intertidal macroalgae are exposed to many abiotic stress factors, and they must regularly react to changes in their environment. We used RNA-seq to describe how Porphyra umbilicalis (Rhodophyta) changes gene expression patterns to interact with different habitats. Tissue samples were taken from a typical habitat along the open-coast of the Northwest Atlantic, as well as from a rare, atypical habitat in an estuarine tidal rapid environment. Differential gene expression analyses suggest that pathogic bacteria and viruses may be a significant factor influencing the transcriptome in the human-impacted estuarine environment, but the atypical habitat does not necessarily induce more stress in Porphyra umbilicalis growing there. We found genes related to nitrogen transport are over-expressed in tissue from the open-coastal site compared to those from the estuarine site, where environmental N levels approach hypertrophic levels. Low N levels impede growth, but high levels are toxic to cells, and we use qPCR to show this species regulates expression of a putative high-affinity $NH_4{^+}$ transporter under low and high N conditions. Differences in expression of this transporter in these habitats appear to be inherited from parent to offspring and have general implications for adaptation to habitat in other species that are capable of asexual reproduction, as well as more specific implications for this species' use in aquaculture.

• 한국물환경학회지
• /
• 제28권1호
• /
• pp.94-101
• /
• 2012

The performance data for eight years from a free-surface-flow constructed wetland system receiving agricultural tailwater were used to analyze denitrification rate and nitrogen treatment characteristics according to season and wetland design. Seasonal difference between growing season (March~November) and winter season (December~February) was shown in the concentration of all nitrogen species. Seasonal nitrogen treatment has similar trend with temperature and measured denitrification rate. The highest denitrification rate was measured in July, but treatment efficiency was most higher in May and June. Nitrogen absorption of vegetation could affect to these wetland performances, therefore dense population of wetland vegetation might be helpful. According to design of wetland, at least 25~50 m of wetland length was needed to decrease effluent T-N concentration to background concentration in growing season. In winter season, wetland needed much longer distance to reduce T-N concentration. Mass removal rate was continuously high through whole year because runoff coefficient was low in winter season. Applicability of constructed wetland was observed for the total maximum daily load that control T-N load.

• 한국표면공학회지
• /
• 제54권6호
• /
• pp.348-356
• /
• 2021

In this study, optical diagnosis of plasma was performed for nitrogen doping in graphene using a horizontal inductively coupled plasma (ICP) system. Graphene was prepared by mechanical exfoliation and the ICP system using nitrogen gas was ignited for plasma-induced and defect-suppressed nitrogen doping. In order to derive the optimum condition for the doping, plasma power, working pressure, and treatment time were changed. Optical emission spectroscopy (OES) was used as plasma diagnosis method. The Boltzmann plot method was adopted to estimate the electron excitation temperature using obtained OES spectra. Ar ion peaks were interpreted as a reference peak. As a result, the change in the concentration of nitrogen active species and electron excitation temperature depending on process parameters were confirmed. Doping characteristics of graphene were quantitatively evaluated by comparison of intensity ratio of graphite (G)-band to 2-D band, peak position, and shape of G-band in Raman profiles. X-ray photoelectron spectroscopy also revealed the nitrogen doping in graphene.

• 한국수산과학회지
• /
• 제44권1호
• /
• pp.64-70
• /
• 2011

Nitrate reductase (NR) is activated by nitrogen sources (${NO_3}^-$ and ${NH_4}^+$) and irradiance. This study investigated the effects of these factors on the NR activity of Ulva pertusa (Chlorophyta) and Ecklonia cava (Phaeophyta). In addition, the ammonium (${NH_4}^+$) and nitrate (${NO_3}^-$) uptake rates of the two species were examined. U. pertusa took up most of the ${NO_3}^-$ and ${NH_4}^+$ in the medium during a 3hour incubation, while E. cava had a relatively high uptake rate after 3 hours. The NR activities of the two species were affected by the nitrogen source and irradiance and were highest when they were exposed to ${NO_3}^-$-rich medium and high irradiance. However, the patterns of NR activity differed between the two species. In ${NO_3}^-$-rich medium and high irradiance, U. pertusa achieved the highest NR activity ($2.01{\pm}0.07\;{\mu}mol$ ${NO_2}^-$ $g^{-1}$ DW $h^{-1}$) within the first 3 hours and then this activity decreased drastically. By contrast, the NR activity of E. cava ($0.36{\pm}0.04\;{\mu}mol$ ${NO_2}^-$ $g^{-1}$ DW $h^{-1}$) was constant for 12 hours. When exposed to darkness, the NR activity of U. pertusa decreased dramatically, while that of E. cava increased gradually for 12 hours. Therefore, E. cava is able to maintain NR activity during the dark because of its adequate carbohydrate reserves and substrate.

• Journal of Plant Biology
• /
• 제6권4호
• /
• pp.5-10
• /
• 1963

농촌에서 식용으로 사용하는 두종의 죽순에 대하여 함유하는 아미노산을 생장부위에 따라 정성분석하였다. 대체로 한 종류가 함유하는 아미노산은 5종 내지 15종이었으며 축순의 생장과정에 따라 함유된 아미노산의 종류는 명명 상위하였다. 식용 죽순에 함유된 필수 아미노산의 종류는 4종에서 9종임을 정성분석 할 수 있었다. 식용죽순에 잇어서도 다른 식물성 식품과 같이 영양가치가 있음을 알아 내었다. 선단부 보다 기부에 아미노산의 종류가 많이 분석된 것은 기부에서 부터 질소대사가 촉진되어 간다는 것을 추측케 하였다.