• Title/Summary/Keyword: Volatile Organic compounds

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Environmental monitoring system research based on low-power sensor network (저전력 센서네트워크 기반 환경모니터링 시스템 연구)

  • Kim, Ki-Tae;Kim, Dong-Il
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.807-810
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    • 2011
  • The sensor network technology for core technology of ubiquitous computing is in the spotlight recently, the research on sensor network is proceeding actively which is composed many different sensor node. USN(Ubiquitous Sensor Network) is the network that widely applies for life of human being. It works out to sense, storage, process, deliver every kind of appliances and environmental information from the stucktags and sensors. And it is possible to utilize to measure and monitor about the place of environmental pollution which is difficult for human to install. It's studied constantly since it be able to compose easily more subminiature, low-power, low-cost than previous one. And also it spotlights an important field of study, graft the green IT and IT of which the environment and IT unite stragically onto the Network. The problem for the air pollution in the office or the indoor except a specific working area is the continuously issue since the human beings have lived in the dwelling facilities. Measures for that problem are urgently needed. It's possible to solve for the freshair of outside with enough ventilation but that is the awkward situation to be managed by person. This study is the system engineering to management for indoor air condition under the sensor network. And research for efficiently manage an option.

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Characterization on Air Pollution of Gunpo City by Measurement of VOCs in Air (대기중 휘발성 유기화합물 측정을 통한 군포시 대기 오염 특성 규명)

  • Park, Hyun-Mee;Kim, Jee-Hyuon;Park, Il-Yong;Kim, Young-Man;Lee, Kang-Bong
    • Analytical Science and Technology
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    • v.15 no.6
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    • pp.556-566
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    • 2002
  • Gunpo city, a medium sized city formed with a basin is populated with a little more than 270,000 peoples and includes the industrial area with about 600 factories. It has been recognized for a long time that peoples living nearby industrial area have complained on serious air contamination due to the geographical and environmental factors. This study was performed on measurement of volatile organic compounds (VOCs) and malodor for the air sampled in various places of Gunpo city, and made comparison with VOCs levels in specific area of Seoul. This work would play important role for the efficient management of air contamination of Gunpo city. Samplings were done in the rooftop of eleven village office buildings including Gunpo station in June 12th, 2001. Analytical results indicate that VOCs levels of Gunpo-1-dong, Gunpo station and Kumjungdong regions neighboring industrial area were much higher than the rest of areas, and this fact shows that the origin for air contamination of Gunpo would be industrial area than car exhaustion gases.

Feasibility test for Solidified Fuel with Cow Manure (고체연료화 방법을 적용한 우분 처리 가능성 평가)

  • Jeong, Kwang-Hwa;Kim, Jung-Kon;Lee, Dong-Jun
    • Journal of Soil and Groundwater Environment
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    • v.22 no.6
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    • pp.112-119
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    • 2017
  • In this study, the availability of cow manure as raw material for solid fuel production was investigated. Since the water content of the cow manure was too high, it was dewatered using a laboratory hydraulic compressure ($11.3kg/cm^2$). The moisture content of the cow manure decreased from 82.01% to 73.36 wt.%. The dewatered cow manure was homogenized by the experimental apparatus and then put into the rotating cylindrical apparatus. From the consecutive processes, the cow ball-shaped pellet which size ranged from 3.0 to 25.0 mm was produced. The major factor for making palletized fuel from cow manure was the moisture content. Based on the experimental data, the moisture content of cow manure for pelletizing cow manure was identified as 65~75 wt.%. When the moisture content of the cow manure was lower than 30 wt.%, the diameter of the pellets maded from cow manure was smaller than 3 mm. On the other hand, when the water content of the cow manure was higher than 75 wt/%, the diameter of the processed pellets tended to be larger than 25 mm. The characteristics of the processed cow manure pellets was analyzed to be in accordance with the livestock solid fuel quality standard. The pyrolysis characteristic of the pellet was analyzed by raising the heating temperature of the experimental equipment from 200 to $900^{\circ}C$. The mass change between of 20 and $130^{\circ}C$ corresponds to the amount of moisture contained in the cow manure. The amount of moisture was about 15% of the total weight of cow manure samples. The cow manure pellet was thermally stable up to $280^{\circ}C$. It can be interpreted that combustion of cow manure pellet does not occur until the surface temperature reaches $280^{\circ}C$. The mass change of pellet between of 280 and $450^{\circ}C$ was considered to be due to the vaporization of volatile organic compounds (VOCs) present in the cow manure pellet. The maximum production of VOCs was showed near $330^{\circ}C$.

Herbicidal Activity of Essential Oil from Palmarosa (Cymbopogon martini) (팔마로사 정유의 살초활성)

  • Hong, Su-Young;Choi, Jung-Sup;Kim, Song-Mun
    • Korean Journal of Weed Science
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    • v.31 no.1
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    • pp.96-102
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    • 2011
  • The objective of this study was to find herbicidal compounds in the essential oil of palmarosa (Cymbopogon martini). Of essential oils from basil (Ocimum basilicum), blackpepper (Piper nigrum), clary sage (Salvia sclarea), ginger (Zingiber pfficinale), hyssop (Hyssopus officinalis), nutmag (Myristica fragrance), palmarosa (Cymbopogon martini), fennel (Foeniculum vulgare), sage (Salvia leucantha), and spearmint (Mentha spicta), the herbicidal activity of palmarosa essential oil, which was determined by a seed bioassay using rapeseed (Brassica napus L.), was highest ($GR_{50}$ value, $201{\mu}g\;mL^{-1}$). In palmarosa essential oil, 11 volatile organic chemicals were identified by gas chromatography-mass spectometry with solid-phase micro-extraction apparatus and the major constituents were geraniol (40.23%), geraniol acetate (15.57%), cis-ocimene (10.79%), and beta-caryophyllene (8.72%). The $GR_{50}$ values of geraniol, citral, nerol, and geranyl acetate were 151, 224, 452, and $1,214{\mu}g\;mL^{-1}$, respectively. In greenhouse and field experiments, foliar application of palmarosa essential oil at the level of $80kg\;ha^{-1}$ controlled weeds effectively. Overall results of this study showed that the herbicidal activity of palmarosa essential oil could be due to geraniol and citral which had lower $GR_{50}$ values.

Laboratory Evaluation of the Accuracy, Precision, and Inter-instrumental Variance of a Portable Photoionization Detector (휴대용 광이온화 검출기의 정확도, 정밀도 및 기기간 차이에 대한 실험실 평가)

  • Choi, Dongmin;Choi, Youngeun;Yoon, Chungsik;Rhie, Kwangwon;Lee, Yunkeun;Lee, Ikmo;Park, Jeongim
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.22 no.3
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    • pp.200-208
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    • 2012
  • Objectives: This study investigated the performance of three separate units of a portable photoionization detector (PID, ppb-RAE 3000) for measuring volatile organic compounds (VOCs) in a laboratory. Methods: A laboratory evaluation of the accuracy, precision, and inter-instrumental variance of three separate units of a portable PID (ppb-RAE 3000) was performed. The evaluation was based on the preparation of a test air sample of known toluene or ethylacetate concentration in a Tedlar$^{(R)}$ bag. The test air sample was monitored and data were logged consecutively by the three PIDs. A certified gas of 50 ppm toluene was also monitored during the test to ensure the reliability of the generated test air sample. Four different concentrations ranging from 0.1 to 2 TLV were used and a series of five measurements for each concentration level was performed. The accuracy was evaluated using National Institute for Occupational Safety and Health (NIOSH) criteria. Results: The results from the oldest ppb-RAE3000 unit among the three test units generally fell outside the NIOSH recommended accuracy criteria of ${\pm}25%$, whereas the other two units produced results which were acceptable at, or greater than, 25 ppm of toluene, or 0.5 TLV. These units also met the NIOSH criteria for some ethylacetate measurements but the results were not consistent. Conclusions: Considering the inconsistent performance of these ppb-RAE 3000 units, this device may not be appropriate for use as an alternative to the standard measurement methods. However, it can serve good survey instruments to identify exposure sources or concentration profiles. For all applications, the ppb-RAE 3000 should be used with frequent calibration checks, additional validation using a reference material, and careful maintenance.

Preparation and Characterization of Electrospun PAN/TiO2 Fiber Mat by Electron Beam Irradiation (전자선 조사에 의한 PAN/TiO2 전기방사 나노섬유 제조 및 특성분석)

  • Kang, Phil-Hyun;Jeun, Joon-Pyo;Seo, Dong-Kwon;Kim, Hyun-Bin;Nho, Young-Chang
    • Polymer(Korea)
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    • v.36 no.1
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    • pp.47-52
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    • 2012
  • Abstract: In this study, PAN/$TiO_2$ fiber mats were fabricated from polyacrylonitrile (PAN) and titanium(IV) butoxide ($Ti(OBu)_4$) by an electrospinning method with various solution concentrations, applied voltages and solution flow rates. The fiber mats were irradiated with an electron beam to induce structural crosslinking and enhance photocatalytic activity. As a result, uniform and bead-free fibers without pits or cracks on surface were obtained at 5 wt% of $Ti(OBu)_4$ solution with 15 kV and 0.02 mL/min flow rate. The PAN/$TiO_2$ fiber mats were irradiated with an electron beam of 1.14 MeV acceleration voltage, 4 mA of current and $1{\times}10^4kGy$. Electron beam irradiation was enhanced the photocatalytic activity of PAN/$TiO_2$ nano fiber mat. The photocatalytic activity of the PAN/$TiO_2$ fiber mat was analyzed by degradation of methylene blue and volatile organic compounds.

The Distribution of Indoor Air Pollutants by the Categories of Public-Use Facilities and Their Rate of Guideline Violation (다중이용시설별 실내공기 오염물질 농도분포 및 기준치 이상 값의 구성비 조사)

  • Joen, Jeong-In;Lee, Hye-Won;Choi, Hyun-Jin;Jeon, Hyung-Jin;Lee, Cheolmin
    • Journal of Environmental Health Sciences
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    • v.47 no.5
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    • pp.398-409
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    • 2021
  • Background: The types and effects of hazardous pollutants in indoor air may vary depending on the characteristics of the sources and pollutants caused by physical and chemical properties of buildings, the influence of outdoor air, and the exposure and use characteristics of residents. Objectives: This study was conducted to provide basic data on the establish of indoor air quality management for different classes of public-use facilities by presenting the characteristics of concentration distribution of hazardous pollutants by different public-use facilities and the status of the excess proportion of exceeding standards. Methods: This study analyzed self-measurement data from public-use facilities taken from 2017 to 2019 A total of 133,525 facilities were surveyed. A total of 10 types of pollutants that have maintenance and recommended standards stipulated in the Indoor Air Quality Control Act from the Ministry of Environment were investigated. The excess proportion and the substances exceeding the criteria for each type of public-use facilities for these pollutants were investigated. Results: As a result of the analysis of the proportion of exceeding the standard for each type of public-use facility, the facilities with the highest excess proportion of the standards for each hazardous pollutant were: PM10 in railway stations (8.93%), PM2.5 in daycare centers (7.36%), CO2 in bus terminals (2.37%), HCHO in postpartum care centers (4.11%), total airborne bacteria in daycare centers (0.69%), CO in museums (0.1%), NO2 in postpartum care centers (1.15%), Rn in museums (0.78%), total volatile organic compounds in postpartum care centers (7.20%) and mold in daycare centers (1.44%). Conclusions: Although uncertainty may arise because this study is a result of self-measurement, it is considered that this study has significance for providing basic data on the establishment in the future of indoor air quality management measures customized for each type of public-use facility.

Exposure to PAHs and VOCs in Residents near the Shinpyeong·Jangrim Industrial Complex (신평·장림 산단 인근 주민의 PAHs 및 VOCs 노출)

  • Yoon, Mi-Ra;Jo, HyeJeong;Kim, GeunBae;Chang, JunYoung;Lee, Chul-Woo;Lee, Bo-Eun
    • Journal of Environmental Health Sciences
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    • v.47 no.2
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    • pp.131-143
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    • 2021
  • Objectives: This study aims to investigate the atmospheric concentration of polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) and the urinary concentration of biomarkers in residents near the Shinpyeong·Jangrim Industrial Complex to compare them with those of residents in a control area. Methods: Hazardous air pollutants (PAHs and VOCs) were measured in an exposure area (two sites) and a control area (one site). Urine samples were collected from residents near the industrial complex (184 persons) and residents in the control area (181 persons). Multiple linear regression analysis was used to identify which factors affected the concentration of PAHs and VOCs metabolites. Results: The average atmospheric concentration of PAHs in Shinpyeong-dong and Jangrim-dong was 0.45 and 0.59 ppb for pyrene, 0.15 and 0.16 ppb for benzo[a]pyrene, and 0.29 and 0.35 ppb for dibenz[a,h]anthracene. The average atmospheric concentration of VOCs was 1.10 and 0.99 ppb for benzene, 8.22 and 11.30 ppb for toluene, and 1.91 and 3.05 ppb for ethylbenzene, respectively. The concentrations of PAHs and VOCs in residents near the Shinpyeong·Jangrim Industrial Complex were higher than those of residents in the control area. Geometric means of urinary 2-hydroxyfluorene, 1-hydroxypyrene, methylhippuric acid, and mandelic acid concentrations were 0.45, 0.22, 391.51, and 201.36 ㎍/g creatinine, respectively. Those levels were all significantly higher than those in the control area (p<0.05). In addition, as a result of multiple regression analysis, even after adjusting for potential confounding factors such as gender and smoking, the concentration of metabolites in urine was high in residents near the Shinpyeong·Jangrim Industrial Complex. Conclusion: The results of this study show the possibility of human exposure to VOCs in residents near the Shinpyeong·Jangrim Industrial Complex. Therefore, continuous monitoring of the local community is required for the management of environmental pollutant emissions.

A Study on the Evaluation of Adsorption Characteristics of VOCs on TiO2 and Al2O3 and Investigation of the Thermal Durability by Molding Various Structures (TiO2와 Al2O3의 기상 VOCs 흡착 특성 평가 및 다양한 구조체로의 성형을 통한 열적 내구성 확보에 관한 연구)

  • Hwang, In-Hyuck;Lee, Sang Moon;Kim, Sung Su
    • Clean Technology
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    • v.24 no.4
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    • pp.280-286
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    • 2018
  • In this study, the adsorption performance of vapor phase VOCs under dry conditions was evaluated by using two metal oxides, $TiO_2$ powder and $Al_2O_3$ powder. BET analysis and ammonia in-situ FT-IR analysis were used to analyze specific surface area and surface acid site. As a result, $TiO_2$ powder and $Al_2O_3$ powder had a specific surface area of $317.6m^2\;g^{-1}$ and $64m^2\;g^{-1}$, respectively. In the case of $TiO_2$ powder, many acid sites were observed on the surface. As a result of evaluating the vapor phase VOCs adsorption performance using two metal oxide powders, $TiO_2$ powder having a relatively large specific surface area and a large number of acid sites exhibited relatively good adsorption performance. In particular, it is considered that the specific surface area directly affects the adsorption performance, and further study on the effect of the acid site is required. Based on the $TiO_2$ exhibited excellent adsorption performance, it manufactured into various forms of honeycomb, hollow fiber and disc. As a result, the adsorption performance was lower than that of the powder, but it is advantageous in view of applicability. In addition, it was confirmed that the disc adsorbent having excellent thermal durability due to the characteristics of the manufacturing process stably maintains adsorption performance even at a high temperature desorption process several times.

Study on Air Quality in the Case of Chemical Fires Using Proton Transfer Reaction-Time of Flight Mass Spectrometer (양자전이 비행시간 질량분석기를 이용한 화학물질 화재 발생 시 대기질 조사 연구)

  • Kim, So-Young;Cho, Dong-Ho;Park, Jungmin
    • Fire Science and Engineering
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    • v.32 no.6
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    • pp.84-90
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    • 2018
  • Chemical accidents occur in various forms, such as explosions, leaks, spills, and fires. In particular, chemical accidents caused by fires seriously affect the surrounding air environment due to soot, causing anxiety to the residents. Therefore, it is important to identify the causative substances quickly and examine the influence of air quality in the surrounding area. In this paper, proton transfer reaction-time of flight mass spectrometry(PTR-ToFMS) was used to identify the causative material in a fire and monitor the air quality in real time. This analyzer is capable of real-time analysis with a rapid response time without sample collection and pretreatment. In addition, it is suitable for quantitative and qualitative analysis of most volatile organic compounds with high hydrogen affinity, to identify the cause of fire and examine the influence of ambient air. In April 2018, when a local fire occurred, methanol, acetone, and methyl ethyl ketone were the main causative agents in PTR-ToFMS.