• 한국환경농학회지
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• 제24권3호
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• pp.238-244
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• 2005

Fertilization effects on changes in soil $CO_2$ flux and organic C in switchgrass (Panicum virgatum L.) land managed for biomass production were investigated. The mean daily soil $CO_2$ flux in the manure treatment was 5.63 g $CO_2-C\;m^{-2}\;d^{-1}$, and this was significantly higher than the mean value of 3.36 g $CO_2-C\;m^{-2}\;d^{-1}$ in the control. The mean daily $CO_2$ fluxes in N and P fertilizer treatments plots were not different when compared to the value in the control plots. Potentially mineralizable C (PMC), soil microbial biomass C (SMBC), and particulate organic C (POC) were highest at the 0 to 10 cm depth of the manure treatment. Potentially mineralizable C had the strongest correlation with SMBC (r = 0.91) and POC (r = 0.84). There was also a strong correlation between SMBC and POC (r = 0.90). Our results indicated that for the N and P levels studied, fertilization had no impact on temporal changes in soil organic C, but manure application had a significant impact on temporal changes in soil $CO_2$ evolution and active C constituents such as PMC, SMBC, and POC.

• Asian-Australasian Journal of Animal Sciences
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• 제29권3호
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• pp.390-395
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• 2016

This study was conducted to investigate the effect of nocturnal light pulses (NLPs) on the feed intake and metabolic rate in geese. Fourteen adult Chinese geese were penned individually, and randomly assigned to either the C (control) or NLP group. The C group was exposed to a 12L:12D photoperiod (12 h light and 12 h darkness per day), whereas the NLP group was exposed to a 12L:12D photoperiod inserted by 15-min lighting at 2-h intervals in the scotophase. The weight of the feed was automatically recorded at 1-min intervals for 1 wk. The fasting carbon dioxide production rate ($CO_2$ PR) was recorded at 1-min intervals for 1 d. The results revealed that neither the daily feed intake nor the feed intakes during both the daytime and nighttime were affected by photoperiodic regimen, and the feed intake during the daytime did not differ from that during the nighttime. The photoperiodic treatment did not affect the time distribution of feed intake. However, NLPs lowered (p<0.05) the mean and minimal $CO_2$ PR during both the daytime and nighttime. Both the mean and minimal $CO_2$ PR during the daytime were significantly higher (p<0.05) than those during the nighttime. We concluded that NLPs lowered metabolic rate of the geese, but did not affect the feed intake; both the mean and minimal $CO_2$ PR were higher during the daytime than during the nighttime.

• 한국토양비료학회지
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• 제44권6호
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• pp.1279-1285
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• 2011

본 연구를 통하여 우리나라 대표적인 농작물 47개의 탄소배출량을 산정하였다. 또한 농작물 생산 시 주요 요소로 투입되는 무기화학비료의 기여도 분석을 통하여 무기화학비료가 차지하는 탄소배출량을 정확하게 파악하였다. 농작물 중 시설감귤의 탄소배출량이 $5.78E+00kg\;CO_2\;eq.\;kg^{-1}$으로 47개 작물 중 가장 높았으며 시설포도 $4.61E+00kg\;CO_2\;eq.\;kg^{-1}$, 착색단고추 $4.34E+00kg\;CO_2\;eq.\;kg^{-1}$, 인삼 $4.23E+00kg\;CO_2\;eq.\;kg^{-1}$, 시설고추 $4.04E+00kg\;CO_2\;eq.\;kg^{-1}$ 순으로 나타났다. 다음으로 농작물 1 kg 생산 시 발생하는 탄소배출량 중 무기화학비료의 기여도는 생산단계, 사용단계를 모두 포함하여 평균 25.19%를 차지하는 것으로 분석되었다. 정부의 정책, 정부 및 기업의 연구 개발을 통한 고품질 저탄소 비료 생산 보급과 같은 노력이 함께 이루어진다면 농업분야의 온실가스 감축에 큰 역할을 할 것으로 기대된다.

• 한국화재소방학회논문지
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• 제24권3호
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• pp.86-92
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• 2010

건자재로서 나무 결함중의 하나는 화재에 대한 취약성이다. 본 연구의 목적은 한국에서 자란 리기다 소나무와 밤나무의 연소성질을 시험하는 것과 건자재로서의 사용에 대한 바람직한 특성을 알아내는 것이다. 콘칼로리미터(ISO 5660-1)는 열방출율과 CO, $CO_2$ 발생과 연기차폐와 같은 연기지수를 측정하는 데 이용되었다. $50kW/m^2$의 외부 열유속하에서 밤나무의 평균열방출율($HRR_{mean}$)은 소나무의 평균열방출율 $68.5kW/m^2$과 비교하여 $70.4kW/m^2$을 나타내었다. 게다가 총열방출율(THR)은 밤나무($120.8MJ/m^2$)가 소나무($81.9MJ/m^2$)보다 높게 나타났다. 이들 결과는 시험된 나무종의 체적밀도에 의존된다. 밤나무는 소나무에 비하여 높은 $CO_{mean}$ 수율과 높은 CO/$CO_2$ 수율을 나타내었다.

• 한국기후변화학회지
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• 제8권4호
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• pp.357-367
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• 2017

Electricity generation in Korea mainly depends on thermal power and nuclear power. Especially the coal power has led to the increase in $CO_2$ emissions. This paper intends to analyze the current status of $CO_2$ emissions from electricity generation in Korea during the period 1990~2016, and apply the logarithmic mean Divisia index (LMDI) technique to find the nature of the factors influencing the changes in $CO_2$ emissions. The main results as follows: first, $CO_2$ emission from electricity generation has increased by $165.9MtCO_2$ during the period of analysis. Coal products is the main fuel type for thermal power generation, which accounts about 73% $CO_2$ emissions from electricity generation. Secondly, the increase of real GDP is the most important contributor to increase $CO_2$ emissions from electricity generation. The carbon intensity and the electricity intensity also affected the increase in $CO_2$ emission, but the energy intensity effect and the dependency of thermal power effect play the dominant role in decreasing $CO_2$ emissions.

• The Korean Journal of Physiology
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• 제3권1호
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• pp.11-18
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• 1969

Tissue homogenates of 10 kinds of human cancer tissues were incubated in medium containing either one of $C^{14}-1,\; C^{14}-2,\;or\; C^{14}-3-lactate $ as a substrate in order to observe the oxidative pathway of lactate in cancer tissues. Lactate concentration in incubation medium was maintained at 50 mg%. At the end of incubation period, gas samples and incubation media were analyzed for total $CO_2$ production rates, radioactivities of respiratory $CO_2$, lactate uptake rates and pyruvate appearance rates. The following results were obtained. 1. Lactate uptake rates in all of cancer tissues examined were less than $2.5\;{\mu}M/hr/gm$ and much lower than those in normal tissues. 2. In the 10 kind of human cancer tissues, total $CO_2$ production rates were less than $10\;{\mu}M/hr/gm$, in all cases. These lower values impressed that oxidative metabolism in tumor tissues generally inhibited as compared with that in normal tissue. On the other hand, fractions of $CO_2$ derived from lactate to total $CO_2$ production rates were less than 15% except one case These facts showed that oxidation of lactate into $CO_2$ was greatly inhibited in tumor tissues. 3. Respiratory $CO_2$ yields from C-1 carbon of lactate in various cancer tissues were mean of 77.7% of total $CO_2$ yield from lactate and $CO_2$ yields from C-2 and C-3 carbon of lactate were mean of 9.1% and 12.6% respectively. These facts showed that carboxyl carbon of lactate oxidized more easily than ${\alpha}\;and\;{\beta}$ carbon of lactate. 4. In 10 kinds of cancer tissues, fractions of disappeared lacteate from media into $CO_2$ and pyruvate, which expressed as RLD $co_2$ and RLDpy respectively, were about 5% in except 3 cases and less than 3% except one case. These fact showed that almost of disappeared lactate from media were degraded into compounds other than $CO_2$ and pyruvate. From the above date, it was suggested that in the oxidative pathway of lactate in cancer tissues $CO_2$ was easily Produced from carboxyl carbon of lactate by oxidative decarboxylation as in the normal tissue, and further oxidation of 2 carbon unit via TCA cycle was inhibited.

• 한국산림과학회지
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• 제99권1호
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• pp.96-101
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• 2010

건자재로서 나무 결함중의 하나는 그의 가연성이다. 본 연구의 목적은 자연 건조된 굴참나무와 느티나무의 연소성질을 시험하는 것과 건자재로서의 사용에 대한 바람직한 특성을 알아내는 것이다. 열방출율과 CO 발생과 연기차폐와 같은 연기지수를 콘칼로리미터(ISO 5660-1)를 이용하여 측정하였다. 50 kW/$m^2$의 열속하에서 굴참나무의 평균 열방출율, $HRR_{mean}$(77.94 kW/$m^2$)은 느티나무의 $HRR_{mean}$(13.06 kW/$m^2$)과 비교하여 높게 나타내었다. 그리고 굴참나무의 평균 비소화면적, $SEA_{mean}$ 41.11 $m^2$/kg은 느티나무의 평균 비소화면적 $SEA_{mean}$ 9.23 $m^2$/kg에 비하여 높게 나타났다. 이들 결과는 시험목의 밀도에 의존함을 보여준다. 그리고 굴참나무는 느티나무에 비하여 높은 CO 발생속도를 나타내었다. 또한 느티나무가 굴참나무에 비해 숯생성으로 인해 난연성이 증대되었음을 보여주었다.

• Journal of the Korean Wood Science and Technology
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• 제43권2호
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• pp.258-264
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• 2015

To evaluate the influence of 3A zeolite on the flame retardant properties of poplar plywood. Ammonium polyphosphate (APP) and 3A zeolite were used as flame retardants to prepare plywood samples. The combustion properties, such as heat release rate (HRR), total heat release (THR), mean CO and $CO_2$ yield, smoke production rate (SPR), and total smoke production (TSP), were characterized by a cone calorimeter. A synergistic effect was observed between 3A zeolite and APP on reducing the HRR and mean CO yield. The probable flame retardation mechanism was proposed.

• Journal of Ecology and Environment
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• 제41권12호
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• pp.328-335
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• 2017

Background: Some researchers have attempted to evaluate the ecological function of various additional services, away from the main point of view on the timber production of Korean forests. However, basic data, evaluation models, or studies on the absorption of air pollutants related to major plant communities in Korea are very rare. Therefore, we evaluated the functional value of the forest ecosystem in Gongju-city. Plantation manual for air purification, supplied from the Ministry of Environment in Japan, was referred to process and method for assessment of air pollutant absorption. Results: Gross primary production was calculated about average 18.2 t/ha/year. It was a relatively low value in forests mixed with deciduous broad and evergreen coniferous compared to pure coniferous forest. Net primary production was the highest value in deciduous coniferous and was the lowest value in mixed forest with deciduous broad and evergreen broad. And the mean sequestration amount of each air pollutant per unit area per year assessed from gross primary production and concentration of gas was the highest with 75.81 kg/ha/year in $O_3$ and was 16.87 and 6.04 kg/ha/year in $NO_2$ and $SO_2$, respectively. In addition, total amounts of $CO_2$ absorption and $O_2$ production were 716,045 t $CO_2$/year and 520,760 t $O_2$/year in all forest vegetation in Gongju-city. Conclusions: In this study, we evaluated the absorption ability of air pollutant in 2014 on forest in Gongju-city area. Gongju-city has the broad mountain area about 70.3%, and area of deciduous broad leaves forest was established the broadest with 47.4% of genus Quercus. Pg was calculated about average 18.2 t/ha/year. The mean sequestration amount of each air pollutant per unit area per year assessed from Pg and $C_{gas}$ was the highest with 75.81 kg/ha/year in $O_3$ and were 16.87 and 6.04 kg/ha/year in $NO_2$ and $SO_2$, respectively. Absorption rates of $O_3$, $NO_2$, and $SO_2$ were the highest in evergreen coniferous forest about $14.87kgO_3/ha/year$, $3.30kgNO_2/ha/year$, $1.18kgSO_2/ha/year$, and the lowest were $5.95kgO_3/ha/year$, $1.32kgNO_2/ha/year$, and $0.47kgSO_2/ha/year$ in deciduous broad forest. In conclusion, it was evaluated that Japanese model is suitable for estimating air pollutants in Japan to Korean vegetation. However, in Korea, there is a very limited basic data needed to assess the ability of forests to absorption of air pollutants. In this study, the accuracy of a calculated value is not high because the basic data of trees with similar life form are used in evaluation.

• The Korean Journal of Physiology
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• 제1권1호
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• pp.33-41
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• 1967

The metabolic patterns of C-1 and C-6-carbon atoms of glucose were observed in the tissue homogenates of the Ehrlich ascites tumor tissue which was incubated for 3 hours in the Dubnuff metabolic shaking incubator. $C^{14}-1-and\;C^{14}-6-glucose$ were used as tracers. The glucose media in which tissue homogenate was incubated was kept at a concentration of 200mg% glucose of carrier and appropriate amount of $C^{14}-1-or\;C^{14}-6-tracer$. At the end of 3 hour incubation, respiratory $CO_2$ samples trapped by alkaline which is placed in the tenter well of incubation flask were analyzed for the total $CO_2$ production rates and their radioactivities. The tissue homogenate samples after incubation were analyzed for their concentrations of glucose, lactate, pyruvate and glycogen and calculations were made on the glucose consumption rate, pyruvate and lactate accumulation rates. The following results were obtained. Data obtained in each group are as follows: 1. In the tissue homogenate, which was incubated with $C^{14}-1-glucose as a substrate, total $CO_2$ production rate averaged $19.0{\pm}5.0{\mu}M/hr/gm$ and the mean specific activity of respiratory $CO_2$ was $840{\pm}296\;cpm/mgC.$ Relative specific activity (RSA) which means the fraction of $CO_2$ derived from medium $C^{14}-1-glucose$ to total $CO_2$ production rate was calculated by ratio of SA of respiratory $CO_2$ and medium $C^{14}-1-glucose.$ RSA was $14.3{\pm}5.0%,$ Accordingly actual $CO_2$ production rate from medium $C^{14}-1-glucose$ showed a mean value of $2.79{\pm}1.35\;{\mu}m$ of which amount was equivalent to the mean value of total glucose consumption rate $(RGDco_2)$, namely, $5.1{\pm}1.3%.$ Lactate and pyruvate appearance rates averaged $7.13{\pm}1.26\;and\;0.21{\pm}0.02{\mu}M/hr/gm,$ respectively. Assuming that these 3 carbon compounds appeared in the medium were derived from glucose, calculations were made that relative glucose disappearance rate into lactate $(RGD_L)$ was $38.0{\pm}5.4%\;and\;RGD_P$ was $1.23{\pm}0.03%.$ Therefore, about 43.3% of the total glucose consumed were accounted for by conversion into the respiratory $CO_2$, lactate and pyruvate. 2. In the second group, which was incubated with $C^{14}-1-glucose$ as a substrate, glucose consumption rate, lactate and pyruvate appearance rates showed almost the same order as the values of the $C^{14}-1-glucose$ substrate group. However, RSA was remarkably decreased showing a mean value of $1.02{\pm}0.13%.$ This fact means that the C-6 carbon of glucose take the minor part in the oxidative metabolism of glucose. The glycogen level in both substrate tissue homogenate showed less than 0.3% of tissue weight. These low value suggested that there was an inhibition of carbohydrate synthesis in the Ehrlich ascites tumor tissue. 3. The catabolic pathway of glucose in the tumor tissue were analyzed on the basis of Bloom's principle from the values of RSA. It was found that in the tumor tissue more than 90% of $CO_2$ derived from glucose were oxidized via the alternate pathway other than principal EMP-TCA cycle such as hexose monophosphate pathway (HMP). From the data described above, it was assumed that in the Ehrlich tumor tissue anaerobic glycolysis proceeds normally although, the oxidation of products of anaerobic glycolysis via the TCA cycle is inhibited resulting in the accumulation of lactate and almost all of oxidative energy from glucose is released by oxidative pathway such as HMP.