• Title/Summary/Keyword: Cold Season

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Abundance and expression of denitrifying genes (narG, nirS, norB, and nosZ) in sediments of wastewater stabilizing constructed wetlands

  • Chon, Kyongmi;Cho, Jaeweon
    • Environmental Engineering Research
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    • v.20 no.1
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    • pp.51-57
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    • 2015
  • As expected, the expression of denitrifying genes in a Typha wetland (relatively stagnant compared to other ponds), showing higher nitrogen removal efficiency in summer, was affected by temperature. The abundance and gene transcripts of nitrate reductase (narG), nitrite reductase (nirS), nitric oxide reductase (norB), and nitrous oxide reductase (nosZ) genes in seasonal sediment samples taken from the Acorus and Typha ponds of free surface flow constructed wetlands were investigated using quantitative polymerase chain reaction (Q-PCR) and quantitative reverse transcription PCR (Q-RT-PCR). Denitrifying gene copy numbers ($10^5-10^8$ genes $g^{-1}$ sediment) were found to be higher than transcript numbers-($10^3-10^7$ transcripts $g^{-1}$ sediment) of the Acorus and Typha ponds, in both seasons. Transcript numbers of the four functional genes were significantly higher for Typha sediments, in the warm than in the cold season, potentially indicating greater bacterial activity, during the relatively warm season than the cold season. In contrast, copy numbers and expression of denitrifying genes of Acorus did not provide a strong correlation between the different seasons.

Experimental Study on Developing of Double Facade System dealing with the various climatic Conditions (다양한 기후조건에 대응하는 이중외피시스템 개발에 관한 실험적 연구)

  • Lee, Keon-ho;Kim, Hyeon-soo;Jang, Dae-hee;Moon, Soo-young
    • KIEAE Journal
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    • v.5 no.2
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    • pp.19-26
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    • 2005
  • Every site has a different given geometrical and climatic condition, which influenced not only the lifestyle of the humanbeings but also the regional architecture. For example, on a cold region, the reduction of the energy loss is necessary, like an igloo, which has a littlest energy loss at hemisphere. Or on a warm region, the house must be protected thermally from the overheating at the sunshining. like a huge shading. An architectural interpretation in the (extreme) moderate climate, like Korea, has always tried to satisfy the both opposite demands simultaneously. A facade, which divides out- and inside, has an ideal position to lead the regulated regional climatic conditions into the room. The Double Facade System(DFS) is well known as an innovative solution in the european countries, like Germany. It provides an reasonable alternative, which can achieve these goals at the same time. A Double Facade System provides an effective sunshade, which means a cooling energy reduction at the warm season. In addition, it enables a natural ventilation at the cold season with the preheating at the system as well as spring and autumn. An ordinary Single Facade System with a inside or outside sun blind provides a solution just for a specified season, like a summer or winter. But the Double Facade System can deal with the various climatic conditions in the moderate climate.

Seasonal variation of assimilable organic carbon and its impact to the biostability of drinking water

  • Choi, Yonkyu;Park, Hyeon;Lee, Manho;Lee, Gun-Soo;Choi, Young-june
    • Environmental Engineering Research
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    • v.24 no.3
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    • pp.501-512
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    • 2019
  • The seasonal effects on the biostability of drinking water were investigated by comparing the seasonal variation of assimilable organic carbon (AOC) in full-scale water treatment process and adsorption of AOC by three filling materials in lab-scale column test. In full-scale, pre-chlorination and ozonation significantly increase $AOC_{P17\;(Pseudomonas\;fluorescens\;P17)}$ and $AOC_{NOX\;(Aquaspirillum\;sp.\;NOX)}$, respectively. AOC formation by oxidation could increase with temperature, but the increased AOC could affect the biostability of the following processes more significantly in winter than in warm seasons due to the low biodegradation in the pipes and the processes at low temperature. $AOC_{P17}$ was mainly removed by coagulation-sedimentation process, especially in cold season. Rapid filtration could effectively remove AOC only during warm seasons by primarily biodegradation, but biological activated carbon filtration could remove AOC in all seasons by biodegradation during warm season and by adsorption and bio-regeneration during cold season. The adsorption by granular activated carbon and anthracite showed inverse relationship with water temperature. The advanced treatment can contribute to enhance the biostability in the distribution system by reducing AOC formation potential and helping to maintain stable residual chlorine after post-chlorination.

The Effects of Long-term Administration of Panax Ginseng and Acanthopanax on Egg Production of Hens (인삼 또는 오가피 장기투여가 닭의 산란에 미치는 영향)

  • Hong, Sa-Ack
    • The Korean Journal of Pharmacology
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    • v.17 no.2
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    • pp.75-78
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    • 1981
  • The effects of Panax ginseng and Acanthopanax on egg production of hens are studied. The hens are fed with three dose levels of ethnaol extract of Panax ginseng and Acanthopanax for 24 months. The weight of each egg and number of egg production per month were compared between control group and treated group. The average weight of egg was not influenced by treatment of Panax ginseng and Acanthopanax. The number of egg production in control group was markedly decreased during cold season (from November to March). Panax ginseng and Acanthopanax markedly improve the egg production during cold season compared with control group.

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Oceanography in the Waters Adjacent to Kamchatka and Kurile islands in the Northwestern Pacific - II (북서태평양 명태 어장의 해황 - 2 . 기후의 특성 -)

  • Han, Young-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.13 no.1
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    • pp.17-25
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    • 1977
  • For four calender years (1971-1974), daily observations of weather conditions (air temperature, humidity, wind speed, wind direction, cloud amount, fog, precipitation etc.) at six stations in the north western Pacific Ocean are used to calculate mean monthly values and to check extra-conditions. At Petropavlosk and Miko'skoe, where indicate the characteristics of modified continental climate, the temperature and humidity are high in summer, and Iow in winter. At A Dak and She Mya, where indicate the characteristics of warm current type maritime climate, humidity is high in all season and annual range of air temperature is nearly negligible. At Simusir and Vasi!' eva, where indicate the characteristics of cold current type maritime climate, humidity is high in all season and annual range of air temperature is $15^{\circ}C.$ As dry cooling power is relatively high in winter, working condition on deck is bad. Most of fogs are advection fog in the area of cold current type climate in summer.

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Measurement of Irrigation Water Temperature and Preventive Measure against Cold Watter Damage to Paddy Rice (벼의 냉수피해 감소를 위한 관개수온 조사와 대책수립)

  • 정상옥
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.41 no.1
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    • pp.52-59
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    • 1999
  • Paddy rice is semi-tropical crop and requires warmirrigation water. If mean water temperature at the water source during the growing period is below 18$^{\circ}C$, sime kinds of water warming mechanism should be taken. In this study irrigation water temperature is measured and preventive measures to cold water damage on paddy rice are suggested. Field observations were performed at 100ha field area downtream of the Unmoon reservoir during the growing season of 1997. Land use, canal system, water temperature at irrigation canals. reservoir, and paddy fields were observed. In addition, growth and yield of the rice at selected plots were observed. Accordingly to the record, cold water damage occurred in this area due to the cold irrigation water supply in 1996. It did not occur because of the effective irrigation water management practice in 1997. However, several preventive measures such as pontoon intake system, using existing weir and construting a new warming pond, are suggested to prevent cold water damage in the future. If a new warming pond is construted to raise irrigation water temperature by 2 $^{\circ}C$, a pond area of 2.94 ha is required.

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A Study on the Cold Weather Concrete using High Early Strength Concrete (조강시멘트를 이용한 한중콘크리트의 특성평가 연구)

  • 임채용;엄태선;유재상;이종열;이순기;이동호
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.261-264
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    • 2003
  • Cold weather can lead to many problems in mixing, placing, setting time, and curing of concrete that can have harmful effects on its properties and service life. Korean Concrete Institute (KCI) defines cold weather as a period when the average daily air temperature is less $4^{\circ}C$ and recommends to cast concrete with special care such as shielding, heating and so on. The use of high early strength cements may improve the rate of hardening characteristics of concrete in cold weather by making it possible to achieve faster setting time and evolving more hydration heat than ordinary Portland cement. Higher early strength can be achieved using Type III cement especially during the first 7 days. The strength increase property of Type III cement at low temperature was studied. As a conclusion the heat or heat insulation curing period can be reduced to 50~75%. So, it can be used for cold weather concreting to reduce construction cost and extend the construction season.

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Periods of Cold Weather Concrete Determined by Korean and Japanese Codes with Climate Data Obtained from Korea (우리나라 한중콘크리트 적용 기간의 KCI와 AIJ 규정에 따른 비교)

  • Lee, Myung-Ho;Zhao, Yang;Park, Jun-Hee;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.326-328
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    • 2013
  • This study compares the periods of cold weather concrete determined by the codes regulated by KCI (Korean Concrete Institute) and AIJ (Architectural Institute of Japan). For the calculation of the periods of cold weather concrete, the climate data for last 5 years obtained from Korean weather forecast station is used. Calculated data indicated that the period of cold weather concrete by AIJ code is longer than that by KCI code. Although global warming causes the decrease of the period of winter season, the temperature differences are large in Korea. Therefore, it is required that the current KCI code should be accordingly upgraded to reflect the weather variation in Korea over time.

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Change of Various Characteristics between Spawning and Non-spawning Season in Diploid and Induced Triploid Far Eastern Catfish, Silurus asotus

  • Lim, Sun Young;Gil, Hyun Woo;Park, In-Seok
    • Development and Reproduction
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    • v.21 no.3
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    • pp.275-286
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    • 2017
  • The purpose of this study is to investigate the differences fatty acids and hormonal parameters in the spawning and non-spawning season between the diploid and induced triploid Far Eastern catfish, Silurus asotus. The measured triploids were produced by cold shock for 50 min at $4^{\circ}C$ in May 2014, the spawning season of diploid was in May, and the non-spawning season was designated in January. Estradiol and testosterone and gonadosomatic index of diploid were higher than those of induced triploid in spawning season (P<0.05), and those of diploid in spawning season were higher than non-spawning season. On the other hand, thyroid stimulating hormone and thyroxine of induced triploid were higher than those of diploid in spawning season (P<0.05). Erythrocyte count of diploid was higher than that of induced triploid in spawning season and non-spawning seasons. Mean corpuscular volume and mean corpuscular hemoglobin of induced triploid were higher than those of diploid in both seasons (P<0.05). Percentages of total saturated fatty acids and n-3 polyunsaturated fatty acids of induced triploid were higher than those of diploid in spawning season, but those of diploid were higher in non-spawning season (P<0.05). Percentages of total mono unsaturated fatty acids and total n-6 polyunsaturated fatty acids of diploid were higher than those of induced triploids in spawning season, while those of induced triploid in non-spawning season were higher (P<0.05). Therefore, induced triploids in the spawning season tend to concentrate on growth and lipid-synthesization, whereas, diploids concentrate on reproduction and gonadal maturation rather than on growth. In non-spawning season, growth and lipid-synthesization were not significantly different between diploid and induced triploid.