• 한국정보통신설비학회:학술대회논문집
• /
• 한국정보통신설비학회 2008년도 정보통신설비 학술대회
• /
• pp.205-208
• /
• 2008

This article presents a methodology for the monitoring of air pollution. All over the world, the interest in the environment has been continuously increasing. Unfortunately, much of this interest is due to emerging problems, such as the greenhouse effect and climate change. For this reason, research into carbon dioxide, which causes the greenhouse effect, is progressing rapidly. This article presents a method of measuring the level of carbon dioxide and other substances in the air through the utilization of mobile-networking base stations and measured data. First of all, sensors are attached at the appropriate position of the mobile-networking base stations. These sensors will measure the air quality in their respective positions, and send sensor data to an urban management center via network gateways and data-collecting systems. The measured data can be used for various purposes. In general, it can be used to measure the air quality, which can then be used as a basis for urban planning. The method described herein utilizes airpollution sensors that are attached to the base stations in different locations and at varying heights. The data obtained hereby will be applicable in many fields. At this time this is simply a methodology, however we hope that it will lead to a practical application.

• 한국구조물진단유지관리공학회 논문집
• /
• 제2권2호
• /
• pp.202-208
• /
• 1998

To investigae the effect of anchorage type of carbon fiber sheet (CFS) on flexural behavior of RC beams, the loading test of RC beams reinforced with CFS was conducted in variable of anchorage Type such as bolting anchorage and U type anchorage using CFS. This study can be summarized as follows ; It is confirmed experimentally that the bolting anchorage and U type anchorage with CFS is very effective to delay the bond failure and prevent the peeling of CFS. Also, the anchorage type applied with this study is very effective to improve the ductility compared with the improving of maximum flexural strength of RC beams. It is believed that the anchorage type used this study must secure the ductile capacity of above 3 for the flexural strengthening of RC beams. In the future, it is required to obtain the data about anchorage type of CFS for utilization of field work as well as investigate the ductile capacity of conventional study of anchorage type

• 자원리싸이클링
• /
• 제21권2호
• /
• pp.9-16
• /
• 2012

본 총설은 수 처리용으로 이용되는 여러 가지 종류의 농업부산물과 염료를 종합평가한 것이다. 염료로 인한 수질오염은 심각한 환경문제를 유발하고 있으나 적절한 기술과 장치는 물론, 수 처리제가 고가로 공급되어 수질관리에 어려움을 겪고 있다. 그에 따른 대체제로 최근에 농업부산물을 이용한 저가흡착제 개발에 높은 관심을 보이고 있는 가운데, 각종 농업부산물의 흡착기능을 조사하였다. 또한 활성탄을 대체할 만한 저가이면서 환경친화적인 염료폐수처리제 개발과 그 효용성을 연구하여 활성탄과 같은 흡착제의 대체가능성을 평가하였다.

• Plant Resources
• /
• 제2권1호
• /
• pp.42-48
• /
• 1999

This study was undertaken to examine the feasibility of black locust (Robinia pseudoacacia) as substrates for several edible mushrooms. For the cultivation of several edible and/or medicinal fungi on black locust, optimum bulk densities, synthetic or semisynthetic additives, natural additives and pretreatment methods were investigated. Fruit body yields of the fungi on various sawdust media composed of different wood species were also analyzed for testing the capability of black locust as a substrate for mushroom production. Mycelial growths decreased proportional when the bulk density increased. The most suitable carbon and nitrogen sources as additives to promote the mycelial growth were sucrose (2%, w/w) and ammonium phosphate (0.2%, w/w) respectively. When corn-powder and beer-waste as natural additives were added to sawdust of black locust showed the significant growth of mycelia. And the optimum mixing ratio was 10:2:1 (sawdust: corn-powder: beer-waste, w/w). Black locust after cold water treatment showed the outstanding mycelial growths. Any significant changes of pH, moisture content (%) and dry-weight losses (%) could not be found among culture substrates (sawdust of black locust, oak and poplar wood) examined before and after harvesting of fruit bodies. Yield of fruit bodies on black locust culture media were comparable with those culture media composed with oak and poplar wood. The present work indicated strongly the potentiality of black locust as raw materials for edible and medicinal mushrooms.

• 한국재료학회지
• /
• 제33권2호
• /
• pp.29-46
• /
• 2023

The electrochemical reduction of carbon dioxide (CO₂) to value-added products is a remarkable approach for mitigating CO₂ emissions caused by the excessive consumption of fossil fuels. However, achieving the electrocatalytic reduction of CO₂ still faces some bottlenecks, including the large overpotential, undesirable selectivity, and slow electron transfer kinetics. Various electrocatalysts including metals, metals oxides, alloys, and single-atom catalysts have been widely researched to suppress HER performance, reduce overpotential and enhance the selectivity of CO₂RR over the last few decades. Among them, single-atom catalysts (SACs) have attracted a great deal of interest because of their advantages over traditional electrocatalysts such as maximized atomic utilization, tunable coordination environments and unique electronic structures. Herein, we discuss the mechanisms involved in the electroreduction of CO₂ to carbon monoxide (CO) and the fundamental concepts related to electrocatalysis. Then, we present an overview of recent advances in the design of high-performance noble and non-noble singleatom catalysts for the CO₂ reduction reaction.

• 한국포장학회지
• /
• 제30권1호
• /
• pp.43-51
• /
• 2024

The addition of oxygen scavengers to food products helps to reduce oxygen exposure, thereby mitigating deterioration, including changes in taste, odor, and color, as well as inhibiting microbial growth. Despite the advantages of the existing non-metallic oxygen removal materials in terms of safety for the human body and suitability for use in microwave ovens, their utilization has been limited due to their slow reaction initiation speed. Therefore, in the current study, sodium metabisulfite was impregnated into various porous media, including halloysite nanoclay, activated carbon, montmorillonite, and silica gel. The oxygen scavenger, produced by impregnating silica gel with sodium metabisulfite, demonstrated a 425% improvement in the initial oxygen removal rate compared to pure sodium metabisulfite. Additionally, sachets containing an oxygen-removing composition with an enhanced oxygen removal rate effectively decreased the oxygen concentration to less than 0.5% on the third day of storage in apple packaging, without elevating carbon dioxide levels. Moreover, it proved effective in preventing the browning of the apple surface. Therefore, the SM/SG oxygen-removal composition can be effectively applied to active food packaging by controlling the oxygen concentration within the packaging.

• 한국습지학회지
• /
• 제20권2호
• /
• pp.173-180
• /
• 2018

상수용, 농업용 등으로 사용되고 있는 낙동강수계의 30개소 호소를 대상으로 새로운 환경기준인 TOC(총유기탄소, Total organic carbon)의 활용성을 평가하였다. 적극적인 수자원의 이용은 양호한 수질을 확보하는 것으로 시작된다. 이는 사람과 자연에게 질적 안정성을 유지할 수 있게 하므로 양호한 수질 확보를 위해 수질기준은 보다 엄격하게 강화되고 있다. 생활환경 중 호소의 유기물질 오염수준을 개선하는 데에는 적절한 유기물질 지표의 활용성이 중요하다. 대상호소에서는 새로 도입된 TOC와 기존에 사용하던 COD(화학적산소요구량, Chemical oxygen demand)간의 상호성이 양의 관계로 나타났는데 이는 TOC의 COD 대체가능성을 의미한다. 그러나 TOC를 활용한 환경기준의 등급이 COD를 활용한 환경기준의 등급보다 더 양호한 것으로 나타나 TOC를 유기물질인자로 이용한 수질등급 수준이 완화된 것과 동일한 효과를 지니게 된다. 이것은 호소의 유기물질 지표를 활용하여 질적 수준을 판단하거나 개선하고자 할 때에 기존의 COD에 직접적으로 대체하기에 TOC의 한계를 나타내는 것이다. 따라서 호소의 질적 안전성을 확보하기 위해서는 수질등급 면에서 TOC의 환경기준 강화가 요구된다. 또 호소의 이용특성에 따라 TOC와 COD간의 상관성에도 큰 차이를 나타내고 있다. 이에 대한 명확한 과학적 규명이 필요하며, 이를 위해 호소의 유기물질 지표의 축적에 기존에 사용하던 COD의 지속적인 모니터링이 요구된다.

• 한국건설순환자원학회논문집
• /
• 제11권3호
• /
• pp.226-233
• /
• 2023

본 연구에서는 국내 레미콘 산업의 산업부산 CO₂ 활용기술 확보를 통한 CCUS 기술의 부상을 목적으로 기체 CO₂를 시멘트 모르타르, 콘크리트 등 시멘트계 재료에 직접 주입하여 사용하기 위해 총 2단계로 나누어 연구를 수행하였다. 1단계에서는 기체 CO₂ 사용에 따라 시멘트 모르타르의 물성에 미치는 영향인자를 도출하고, 영향인자에 대해 기준 배합과 동등한 물성발현을 위한 재료적 검토를 포함하였다. 1단계 검토결과, 물/시멘트비 조정 등이 일반적인 재료적 접근에 의한 물성확보는 한계가 있는 것을 확인하였으며, 이에 2단계에서는 CO₂ 사용방법, 시멘트 모르타르의 비빔방법 등 CO₂를 주입한 모르타르의 최적화에 대한 전반을 포함하였다. 기체 CO₂의 모르타르 주입 시 나타나는 물성변화에 대한 해결방안과 압축강도 성능증진을 위한 기체 CO₂의 최적 주입율 및 주입시간을 도출하였다. 그 결과, 일반 모르타르와 비교하여 최종 비빔 후 120초 이상의 추가비빔시간이 요구되는 것을 확인하였으며 유동성 및 압축강도 발현성능을 고려한 기체 CO₂의 적정 주입율은 시멘트량 중량 대비 0.1~0.2 %로 도출되었다. 기체 CO₂ 주입시간 증가에 따른 추가적인 강도증진효과는 나타나지 않았으며, CCUS 기술로써 활용되기 위해서는 CO₂ 고정화량 평가 등 미세분석을 통한 추가적인 검토가 필요하다.

• 한국식품저장유통학회지
• /
• 제3권2호
• /
• pp.155-170
• /
• 1996

In order to determine the physiolosical characteristics of plum fruits(Oishi wase) during maturation and guilty according to temperature after harvest, (2-chloroethyl) phosphonic acid(ethphon) 390ppm was sprayed on plum tree 11days before commercial matuarity in Suwon area. And also this study was acted to investigate fruits quility(Formosa) influenced by temperature(room, low) and polyethylene films(0.03, 0.06, 0.1mm), 1. Effect of ethphon on the fruits maturation and fruits(Oishi wase) quility according to temperature ofter harvest. Ethephon stimulated fruits ripening but the firmness was reduced rapidly. Soluble solids and titratable acidity was not very different than each treatment. Carbon dioxide and ethylene production were advanced and the production peak were shown earlier by ethephon treatment as compared with control fruit. Anthocyanin development was enhansed rapidly by ethephon treatment but it exerted a bad influence on fruits color after harvest, The soluble sugars in fluits were mainly glucose, sucrose, and fructose. Those content were higher in treated fruit than control. The organic acid was mainly malic acid. The shelf life was less than about 5days at room temperature and about 10 days at low temperature. 2. Fruits(Formosa) quility as affected by polyethylene film bagging. The polyethylene films well maintained the firmness both room and low temperature. Low temperature was more effective in maintaining titratable acidity than room temperature, especially polyethylene films. On the Other hand, soluble solids content was not shown wide differance between room and low temperature. Polyethylene film showed a high resperation rate, the rate was higher at room temperature than low temperature and thicker films revealed higher rate. Otherwise, ethylene production was low in all treatment Polyethylene film inhibited the coloration of fruits, decreased anthocyanin content. Fruits coloration delayed by low temperature in control. The shelf life of plum fruits was about 6 days at room temperature and 13 days at low temperature in control Polyethylene film had no advantage on shelf life both at room and low temperature.

• Applied Biological Chemistry
• /
• 제35권1호
• /
• pp.30-35
• /
• 1992

Polyvinyl alcohol(PVA)을 탄소원으로 이용할 수 있는 세균 J2W 균주와 J2Y균주를 토양으로 부터 분리하였다. 분리된 이들 균주는 각각 별도의 순수배양으로는 PVA를 이용할 수 없었으나 이들 균주를 혼합배양 하였을 경우는 PVA를 분해 이용할 수 있었으며, 또한 PVA의 중합도(중합도 500, 1500, 2000)에 관계없이 이용할 수 있었다. 이들 두 균주는 다른 PVA 이용 공생균주 Pseudomonas PW와 Pseudomonas G5Y와 재구성하여 혼합배양 하였을 때 J2Y균주와 Pseudomonas PW, J2W 균주와 Pseudomonas G5Y 균주와의 혼합배양에서는 PVA를 이용할 수 있었다. 이들 두 균주는 동정 결과 J2W균주는 Pseudomons pseudomallei 근연균으로, J2Y는 Xanthomonas campestris 근연균으로 동정되었다.