• The Korean Journal of Zoology
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• v.36 no.2
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• pp.159-174
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• 1993

까치 살모사(AEkistrodon snatilis)의 활동기와 동면기에서 일반적인 혈액성상과 혈액내 가스함량의 변화 또한 위장관 점액세포에 대한 형태적 및 조직화학적 변화 양상을 규명 비교하고자 한다 활동기와 동면기에 까치 살모사의 혈액내 총이산화탄소량(TCO2). 이산화탄소부분압(PCO2), 산소압(PO2)과 pH는 활동기보다 동면기에 증가하였으며, 적혈구수, 혈색소, 적혈구 용적 백분율은 활동기보다 동면기에 약간 증가하는 경향이었다. 또한 백혈구수는 활동기보다 동면기에 뚜렷한 감소를 보였다 활동기와 동면기의 위점막에서는 현저한 차이는 없으나, 소장 점막은 동면기에 그 주름수가 감소하고 높이가 낮아지며 점액세포가 위축되었으며, 위 표면 점액세포는 활동기에 중성 점액질과 약간의 Sialomucin을 포함한 산성 점액질로 구성되었으나 동면기에는 중성 점액질과 Sialomucin이 약간 감소하였다 위점액경세포는 활동기에 중성 점액질만을 포함하고 있었으나. 동면기에는Sialomucin을 포함한 산성 점액질이 소량 검출되었다 소장 점액세포는 활동기에 산성점액질과 중성 점액질로 구성되었으며. 산성 점액질에는 Sulfomucin과 Sialomucirr이 포함되어 있었으나 동면기에는 Sulfomucin과 Sialomucin이 다소 감소하는 경향이었다 주사전자현미경 관찰을 통한 까치 살모사의 위장관 표면 상피세포의 미세구조적 변화는 각동면기 별로 차이를 인정할 수가 있었다. 위장관점 막 상피세포는 활동기에 비해 동면기에 상당한 구조적 위축현상을 보이는 경향을 알 수 있다.

• Fire Science and Engineering
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• v.16 no.3
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• pp.77-83
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• 2002

We measured flame extinguishing concentration and flue gas composition in the n-heptane fuel cup-burner system using inert gas agents such as nitrogen, argon, carbon dioxide and their mixtures. The flame extinguishing concentration of binary gaseous mixture was well predicted by model which contains the flame extinguishing concentration and composition of pure components. The higher average specific gravity of the mixed inert gas agents, the more excellent flame extinguishing performance. And the structure of enclosed space also affects the fire extinguishing. The composition of carbon dioxide in the flue gas was decreased with increasing extinguishing agent used. Nitrogen monoxide production is not related with increasing nitrogen, but increased at rapid mass flow rate of air in the cup-burner.

• Journal of Mushroom
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• v.10 no.1
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• pp.3-8
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• 2012

In this study, to produce Flammulina velutipes mushroom liquid spawn efficiently and effectively the effects of explosive aeration (supplying air with tiny bubbles) of the liquid culture medium on carbon dioxide concentration and residual sugar content in the medium on carbon dioxide concentration and residual sugar contentin the medium were measured. Carbon dioxide concentrations were measured at the outlet of the incubator. On the third day the explosive aeration greatly increased mycelial growth of the liquid spawn, and carbon dioxide concentration also greatly increased but decreased after 5 days. Free sugar contents in the liquid culture consistantly decreased up to 7 days and thereafter was not detected. The weight of the mycelia were maintained similar levels after 3 days. Total nitrogen content in the liquid medium constantly decreased during the 11days of explosive aeration. The content of free sugars in 7 days of culture was the lowest level, thus the inoculum incubated for 6~7 days was thought to be the most effective. Carbon dioxide concentration measurement at the outlet of the container during the liquid spawn incubation required low cost but was efficient to estimate the degree of mycelial growth to be used as a simple indicator.

• Clean Technology
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• v.17 no.4
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• pp.389-394
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• 2011

A compact adsorption-based process for removal of carbon dioxide and nitrogen from natural gas has been discussed. Among the adsorption-based processes, especially, the pressure swing adsorption (PSA) process has been a suitable unit operation for the purification and separation of gas because of low operation energy and cost. A step cycle is made up of pressurization, feed, equalization, blowdown and rinse. In this work, the PSA process is composed of zeolite 13X and carbon molecular sieve (CMS) for removal of carbon dioxide and nitrogen from mixed gas containing $CH_4/CO_2/N_2$ (75:21:4 vol%). A CMS selectively removes carbon dioxide and a zeolite 13X separates nitrogen from methane. CMS is investigated experimentally due to the high throughput of the faster diffusing component ($CO_2$). The gas composition of top, bottom and feed tank was measured with the gas chromatography (GC) using TCD detector, helium as carrier gas and packed column for analysis of methane, carbon dioxide, and nitrogen.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.195-195
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• 2011

본 연구는 방염성능시험에 의한 필름 및 도료처리 시료를 대상으로 화재 시 발생하는 연소가스 중의 독성에 대하여 NES 713 방법에 의해 분석하고, 독성지수를 확인함으로써 연소 시 인체에 미치는 영향을 간접적으로 확인해 보고자 하였다. 기존 방염제품 중 필름과 도료처리 그리고 도료처리 후 기간이 경과한 시료의 3가지로 실험군을 구분하였으며, NES 713 방법으로 연소가스를 분석하고 독성지수를 평가하였으며, 추가로 기존의 국내 노출기준과의 비교를 수행하였으며, 국내 NES 713 방법을 활용한 선행연구들을 참조하였다. 발암가능 추정물질인 아크릴로니트릴은 총 18개의 시료에서 검출되었으며, 포름알데히드는 9개의 시료에서 검출되었다. 염화수소와 브롬화수소는 각각 5개의 시료들에서 검출된 반면에 도료처리된 시료에서는 각각 1개만이 검출되었다. 그 외 일산화탄소와 이산화탄소 그리고 질소산화물은 모든 시료에서 공통적으로 검출되었다. 독성지수는 최소 3.5에서 최고 9.4의 값을 갖는 것으로 나타났다. 본 연구에서 수행한 NES 713 분석결과와 독성지수 산출 및 기존 국내 노출기준과의 비교를 수행해 본 결과는 다음과 같았다. 첫째, 현행 국내 기준 상 방염제품의 독성시험 등에 관한 기준이 없고, 둘째, 방염제품에 대한 연소가스 독성 등을 평가한 선행연구가 제한적이라는 점에서 의미가 있을 것으로 사료된다. 하지만 독성지수의 적용이 국내에서 이루어지고 있지 않은 현실에서 산출도나 독성지수의 위해정도를 평가하기 어렵고, 시료의 수량이 총 18개로서 많지 않았다는 점에서 전체 방염제품의 연소가스 독성의 잠재적인 위험성을 추정할 수는 있지만 대표성을 갖기에는 문제점이 있다는 한계성을 벗어날 수 없었다. 따라서 향후 후속 연구에서는 보다 많은 방염제품들을 대상으로 무작위 선정을 통한 연구 설계 및 실험 연구가 수행된다면 보다 객관적이고 대표성을 지닌 연구결과를 도출할 수 있을 것으로 기대한다.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.130-134
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• 2008

Modern automated culture systems have increased the isolation rate of microorganisms and shortened the time to detection, reducing experimental errors in diagnosis of infecting agents. BacT/ALERT 3D system is based on the colorimetric detection of $CO_2$ produced by the growing microorganisms. In order to evaluate the efficiency of the detection system, sterility test were performed using 6 bacteria. With standard aerobic and anaerobic bottles containing the liquid media, both three aerobic bacteria (P. aeruginosa, M. luteus, B. subtilis) and a facultative bacterium S. aureus were detected up to 1 CFU in 31.44 hr. In addition, growth of anaerobic C. sporogenes was recognized up to 1 CFU in 15.96 hr. The slowly growing bacteria P. acnes was detected up to 10,000 CFU in 129.36 hr. In comparison with conventional culture method, BacT/ALERT 3D automated culture system was more sensitive and saved detection time up to$2\sim10$ hr. Therefore, this automated culture system enables to efficiently detect bacteria in clinical samples and biological medicines.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.6
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• pp.123-132
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• 2012

Gas sensors has been used very differently that depending on following purposes; Automotive (exhaust gas, fuel mixture gas, oxygen, particulates), agriculture / food industry (fresh, stored, CO2, humidity, NH3, nitrogen oxide gas, organic gas, toxic gas emitted from pesticides and insecticides), industrial / medical (chemical gas, hydrogen, oxygen and toxic gases), military (chemical weapon), environmental measurements (CO and other air pollution consisting of sulfur and nitrogen gas), residential (LNG, LPG, butane, indoor air, humidity). The types of industrial toxic substances are known about 700 species and many of these exist in gaseous form under normal conditions. he multi-gas detection sensors will be developed for casualties that detect the most important and find easy three kinds of gases in marine plant; carbon dioxide(CO2), carbon(CO), ammonia(NH3). Package block consists of gas sensing device minor ingredient, rf front end, zigbee chip. Develope interworking technology between the sensor and zigbee chip inside a package. Conduct a performance test through test jig about prototype zigbee sensor module with rf output power and unwanted emission test. This research task available early address when poisonous gas leaked from large industrial site and contribution for workers' safety at the enclosed space.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.513-517
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• 2013

We investigated the properties of impregnated activated carbons, a commercial adsorbent for the individual protection equipment, and examined CO adsorption and oxidation to $CO_2$. The surface area, pore volume and pore size were measured for four commercial samples using Brunauer-Emmett-Teller/Barrett-Joyner-Halenda (BET/BJH), and atomic compositions of the sample surface were analyzed based on SEM/EDS and XPS. Impregnated activated carbons containing Mn and Cu for fire showed the catalytic CO oxidation to $CO_2$ with a high catalytic activity (up to 99% $CO_2$ yield), followed by the CO adsorption at an initial reaction time. On the other hand, C: for chemical biologial and radiological (CBR) samples, not including Mn, showed a lower CO conversion to $CO_2$ (up to 60% yield) compared to that of fire samples. It was also found that a heat-treated activated carbon has a higher removal capacity both for CO and $CO_2$ at room temperature than that of untreated carbon, which was probably due to the impurity removal in pores resulted in a detection-delay about 30 min.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.475-480
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• 2011

This study was conducted to investigate the effects of different feeding level of TDN (Total Digestible Nutrients) on the generation of main greenhouse gases such as carbon dioxide and methane in Hanwoo cows. The diet TDN (kg) adjusted to achieve ADG of 0 g/day (Control), 200 g/day (T1), and 400 g/day (T2) of the maintenance level TMR (Total Mixed Ration) delivered twice a day at 08:30 and 17:30. Cow are housed in a respiration chamber and the environmental temperature was maintained at $20^{\circ}C$. The gases were measured for 24 hours using the multi-detector instrument Mamos-300. The analyzed methane emissions of T1 and T2 were 33.5% and 69.6% higher than control, respectively, and the carbon dioxide emissions were 21.1% and 40.6% higher than control. Also, the hourly pattern of carbon dioxide and methane production were showed very similar emission. Gas production showed peak after 1 hour of feeding and this gap was wider in the afternoon than in the morning hours. It is clearly conducted that $CO_2$ and $CH_4$ emissions were different by limited intake levels of feed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1847-1855
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• 2015

Supercritical carbon dioxide ($SC-CO_2$) treatment has been becoming an important method for substituting the use of organic solvents for samples extraction prior to analysis due to its low toxicity, ease of handling, low cost of disposal etc. Freeze-dried bovine liver was treated with $SC-CO_2$ under different pressures (200, 300, and 450 bar) in order to investigate effects on physicochemical properties and reduction of microbial load. The yield of lipid extraction from bovine liver by $SC-CO_2$ treatment increased with increasing pressure, with values of 84, 86, and 90% in response to 200, 300, and 450 bar, respectively. Results of high performance liquid chromatography analysis showed that vitamin A and coenzyme $Q_{10}$ ($CoQ_{10}$), which is soluble in lipid, were almost removed from bovine liver by $SC-CO_2$ treatment. Saturated fatty acids ratio of bovine liver decreased with increasing pressure, whereas polyunsaturated fatty acids increased with increasing pressure. Total content of amino acids in bovine liver treated by $SC-CO_2$ was less than that of the control sample without treatment. The number of aerobic bacteria in bovine liver, which was stored at $5^{\circ}C$ for 5 days and freeze-dried, decreased from 6.2 to 4.2 log CFU/g by $SC-CO_2$ treatment at 100 bar for 3 h. Interestingly, coliform bacteria were not found in the bovine liver sample by $SC-CO_2$ at 100 bar for 3 h under all storage conditions. This indicates that $SC-CO_2$ treatment can effectively reduce coliform bacteria in the food matrix even at low moisture. In conclusion, freeze-dried bovine liver by proper $SC-CO_2$ treatment may be used as a potential high protein source, with increasing microbial safety and stability of lipid oxidation.