• Title/Summary/Keyword: air respiration

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Setting time properties of cement matrix according to photosynthetic bacterial dilution ratio (광합성 세균 희석 비율에 따른 시멘트 경화체의 응결 특성)

  • Pyeon, Su-Jeong;Kim, Dae-Yeon;Lim, Jeong-Jun;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.11a
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    • pp.89-90
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    • 2018
  • In recent years, harmful substances and fine dust in the air are caused by respiratory and cardiovascular diseases through various mechanisms when they are introduced into the human body through respiration, thereby exacerbating human health and causing cancer by prolonged exposure do. In order to prevent such fine dust from being introduced into the room and to improve indoor air quality, improvement of air quality has attracted attention. Among indoor air pollutants, fine dust and CO2 are pollutants that are directly affected by indoor number and activity. The purpose of this study is to evaluate the basic performance of cement matrix using photosynthetic bacteria as a basic study of fine dust and CO2 adsorption type matrix to suppress indoor air pollution and improve air quality.

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Automatic Control Of Dissolved Oxygen In Activated Sludge Aeration Tank

  • Park, Kwang-Soo;Heo, Nam-Hyo;Lee, Hae-Goon;Han, Gee-Baek;Kim, Chang-Won
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.2
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    • pp.113-119
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    • 1999
  • The quality of the effluent from an activated sludge aeration tank can deteriorate when the substrate removal rate decreases due to an abrupt reduction in the DO concentration, which is affected by such operating conditions as the loading rate, temperature, wastewater composition, and so on. In this research, a DO control system that includes a PI (proportional-integral) controller/Hiraoka controller was developed and applied to a pilot-scale activated sludge process, then its acceptability was estimated. The applicability of the respiration rate to DO control was also estimated. The respiration rate indicated a variety of input organic loading rates, which is the main disturbance to the DO concentration in an aeration tank. When the influent concentration incrementally decreased and increased between CODcr 1,000 mg/l and 100 mg/l, the control system with a PI controller exhibited a good llperformance-the average DO concentrations were 2.00$\pm$0.14 mg/l and 1.88$\pm$0.15 mg/l (set value was 2.0 mg/l), respectively, and the settling time was just 10 minites. When the control system was operated for 4 days, the DO concentration was 1.99$\pm$0.18 mg/l and 32.6% of the air flowrate was saved. However, the fluctuations in the respiration rates and air flowrates were severe, which could be harmful to the stability of the biomass and mechanical stability of the blower. A possible approach to solve this problem may be the simultaneous control of the loading rate and DO concentration.

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Physiological Response of Panax ginseng to Temperature I. Old experience, distribution, germination, photosynthesis and respiration (인삼의 온도에 대한 생리반응 . 옛경험, 분석, 발아, 광합성, 흡수)

  • Park, Hoon
    • Journal of Ginseng Research
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    • v.3 no.2
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    • pp.156-167
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    • 1979
  • Physiological characteristics of Panax ginseng were reviewed in relation to temperature. According to the old literatures and records of cultivator's experiences it was elucidated that ginseng plants require light but hate high temperature and that the cultural methods were developed to content two characteristics in contradiction. Low temperature (cool climate) during growing season seems (or ginseng to be essential and to escape from the extreme coldness according to air and soil temperature of natural habitat and cultivated area. Optimum temperature of dehiscence (15∼below 20$^{\circ}C$) is a little higher than that of germination (10∼15$^{\circ}C$). Optimum temperature for growing of new buds (18∼20$^{\circ}C$) is similar to that for growing after emergence (17∼21$^{\circ}C$). Dormancy of both matured embryo and new buds is broken at the same temperature (2∼3$^{\circ}C$). It seems reasonable that optimum temperature of photosynthesis (22$^{\circ}C$) is similar to that of growth. Respiration quotients of various organs or of whole plant ranged from 1.7 to 3 incrased with high temperature. Respiratory consumption and oxygen limitation seem to be potential factors to induce decay during dehiscence and germination of seeds and root rot in fields. Research on organ differentiation. photosynthesis, respiration and growth with age is needed for the development of cultivation methods.

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Diurnal and Seasonal Changes of Stem Respiration in Black Locust (Robinia pseudoacacia)

  • Kim, Myung Hyun;Nakane, Kaneyuki;Lee, Jeong Taek;Bang, Hae Son;Na, Young Eun
    • Journal of Korean Society of Forest Science
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    • v.95 no.2
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    • pp.168-173
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    • 2006
  • Stem respiration rate ($R_{stem}$) was examined using an open flow system on black locust (Robinia pseudoacacia L.). $R_{stem}$ exponentially increased with increasing air and stem temperature during measurement period and was most closely correlated with stem temperature. It was more closely correlated with stem temperature observed 0.5-2.0 hrs earlier than with current stem temperature, that is, there was time lag between the increase of stem temperature and the efflux of $CO_2$ from stem. $R_{stem}$ gradually increased from spring to summer, and then decreased during autumn. $R_{stem}$ ranged from 0.13 to $4.44{\mu}mol$ $CO_2m^{-2}s^{-1}$. $Q_{10}$ decreased with increasing stem temperature, and varied along position (or diameter) within trees during the same period, especially during the growing season. On the other hand, time lag was shortened with increasing temperature.

The Responses of Yukbo Strawberry (Fragaria ananassa Duch.) Fruit to Nitric Oxide

  • Eum, Hyang-Lan;Lee, Seung-Koo
    • Food Science and Biotechnology
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    • v.16 no.1
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    • pp.123-126
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    • 2007
  • The quality of Yukbo strawberry (Fragaria ananassa Duch.) fruit declines rapidly after harvest. Therefore, we examined the effects of nitric oxide (NO) on its respiration rate, quality, and shelf life. Strawberries were fumigated for 5 hr at 0, 50, 100, 200, or $500\;{\mu}L/L$ NO atmosphers, followed by a hold at $18^{\circ}C$ in air. Treatment with NO delayed the onset of ethylene production ad reduced respiration, which at $18^{\circ}C$ resulted I a maintained quality and prolonged shelf life. The NO-treated strawberries were also firmer and had a lower incidence of disease than the untreated fruit. The effect of NO on fruit quality was dose-dependent. Strawberries that were treated with low and high concentrations of 50 and $500\;{\mu}L/L$ No, respectively, had severe disease incidence and were of poor quality. Treating with NO at a concentration of $200\;{\mu}L/L$ appeared to slow down the ripening and senescence of fruit stored at $18^{\circ}C$. Calyx browning, respiration, and rot development progressed more quickly in strawberries treated with $500\;{\mu}L/L$ NO compared to those treated with $200\;{\mu}L/L$ No.

A Numerical Study of the Air Quality Inside Automobiles According to the HVAC System Operating Conditions (HVAC 작동특성에 따른 자동차 실내 공기질 평가에 관한 수치해석적 연구)

  • Yoon, Seonghyun;Seo, Jinwon;Choi, Yunho
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.3
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    • pp.299-309
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    • 2014
  • When using an automotive heating, ventilation, and air conditioning (HVAC) system, we can obtain fresh outside air while maintaining the interior vehicle temperature. In this study, a correction equation considering experimental data for automotive indoor air leakage is defined to simulate the ratio of fresh air to recirculated air in the automobile cabin. With this correction equation, numerical results are compared with experimental data and validated. The $CO_2$ concentration in the automotive cabin is evaluated by considering various boarding conditions and mass flow rates of the HVAC system. The $CO_2$ concentration model derived in this study is expected to be used to control the effective air conditioning and become a basic research tool for automotive air quality control system development.

A Model for Carbon Dioxide Exchanges of Pinus densiflora Population (소나무 개체군의 이산화탄소 교환 모델)

  • Suh, kyeHong
    • The Korean Journal of Ecology
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    • v.19 no.1
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    • pp.9-19
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    • 1996
  • The model PINUSCO2 hased of physiology was creted to simulate carbon dioxide budget in a population of red pine(pinus densiflora) which is one of the dominant species in Korea. Driving forces of PINUSCO2 are global radiation, maximum and minimum air temperatures. State variables fo the model are standing crops of leaf, branch, trunk and root of the red pine population. PINUSCO2 calculates net photosynthesis of canopy and respiration of each organ with 1 hour time step. PINUSCO2 estimated the annual gross productivity, respiration and net productivity of the red pine population as 43.99, 24.55, and 19.44 ton CO2·ha-1·yr-1, respectively, at the study sity(35°58′00"N, 128°25′35"E). PINUSCO2 showed that the red pine population grew mainly in spring and fall, and that in summer daily net population productivity frequently became negative.

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Habitats and Air Uptake Based on Analysis of Skin Structure of Two Korean Bullheads, Pseudobagrus brevicorpus and P. koreanus (Pisces; Bagridae}

  • Park, Jong-Young;Kim, Chi-Hong
    • Animal cells and systems
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    • v.11 no.2
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    • pp.155-160
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    • 2007
  • The skin of the Korean bullheads, Pseudobagrus brevicorpus and P. koreanus, is composed of epidermis, dermis and subcutis. The epidermis has three layers, the outermost layer, middle layer and stratum germinativum. The epidermis consists of two types of gland cells, an unicellular mucous cell of sulfomucin and a large club cell having sometimes two nuclei. The epidermis has numerous intraepithelial blood vessels in P. brevicorpus but not at all in P. koreanus. Lymphatic spaces containing lymphocytes are well developed in mainly the stratum germinativum. The dermis lacks scales and consists mostly of bundles of coarse collagen fibers. The collagen bundles are arranged in parallel to each other in the dorsum and lateral region toward the dorsum, but vertically at intervals in the abdomen and lateral region toward the abdomen. Considering this unique skin structure, the two species are likely to exercise cutaneous respiration as a dual respiratory system to overcome hypoxic conditions which frequently occurs in their habitats.

Chemosensory-Event-Related Potentials to Olfactory Stimulations

  • Min, Byung-Chan;Park, Se-Jin;Kim, Chul-Jung;Masashi Wada
    • Science of Emotion and Sensibility
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    • v.1 no.2
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    • pp.113-119
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    • 1998
  • A new device introducing brief pulses of odorozed air synchronized with subject's respiration to human subjects creating a positive response was developed. By the using superimposition technique of an evoked potential the positive responses to skatole in normal subject's were distinguishable. The odorant pulse trigger was the subject's respiration. Responses to aerosolized skatole consisted mainly of a positive wave with a peak latency of approximately 150 ms. In our cases, saturation of responses was found after 4-5 averagings with the responses becoming most clear after 7-8 averagings. And in cases of Alzheimer disease very quick adaptation was recognized.

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Determination on the Optimal Harvest Date of Apples for CA Storage (CA 저장을 위한 사과의 최적 수확시기 결정)

  • 정헌식;정신교
    • Food Science and Preservation
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    • v.1 no.1
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    • pp.29-36
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    • 1994
  • This study was carried out for the establishment of optic harvest date and storage condition of 'Fuji' apple for CA storage. Apples were picked at 10 day intervals from 17 Sept to 27 Oct.. Apples were analyzed for respiration rata, weight flesh firmness, titratable acidity, soluble solid, total sugar, reducing sugar, surface color and thiault value. In 1990, the optimal harvest season could be judged between 17 Oct. and 27 Oct. from the results of respiration rate rise and change of quality properties. Apples harvested on 27 Oct. wert stored at 2$^{\circ}C$ and 90~95% RH in 1%O2 + 3%CO2, 3%O2 + 3%CO2 and air for 9 months. After 9 months of storage, apples kept in CA storages had beater quality than apples kept in refrigeration storage. Especially, apples kept in 1%O2, + 3%CO2 were fumer and more acid than those kept in 3%O2 + 3%CO2 At the sensory evaluations, apples stored in CA were rated higher quality than apples stared refrigeration.

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