• Journal of Life Science
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• v.10 no.4
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• pp.368-373
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• 2000

Enteroviruses in the environment pose a public health risk because they can be transmitted via the fecal-oral route through contaminated water, and low numbers are able to initiate an infection in humans. Because the levels of viruses typically found in environmental water and drinking water are low, they must be concentrated from hundreds to thousands of liters of water. Therefore, the main goal of this study was the development of a rapid, simple and efficient procedure to concentrate, isolate and detect enteroviruses from environmental water samples. Viruses were first concentrated by adsorption to 1 MDS cartridge filter and then eluted with approximately 0.5 liter of 1.5% beef extract/0.05M glycin(pH 9.4). In this study, several procedures to concentrate and purify intact viruses from beef extract obtained from the adsorbent filters were tested. Among them, organic floccuration was the best reliable method for reconcentration. sample volume could be reduced to 200∼400 folds and the efficiency of virus recovery through the procedure was over 72%. Finally, the samples were filtered through a membrane disk filter and then analyzed by either the plaque assay or combined cell culture-polymerase chain reaction.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.1
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• pp.37-53
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• 1993

The polynuclear hydrocarbons (PAHs) emitted from coke oven standpipe were sampled using three sampling systems, including glass fiber filter+silver membrane filter, glass fiber filter+silver membrane filter+XAD-2 adsorbent tube, PTFE membrane filter+XAD-2 adsorbent tube, extracted by methylene chloride and analysed by gas chromathography using flame ionization detector. The results of this study were as follows. 1. Because the amounts of coke oven emissions(COE) were large, the analyses of PAHs were simple and possible without evaporation and concentration. Although the generation of COE was high during early stage of coking, the airborne concentration of PAHs was low and increased during late coking. 2. The contents of PAHs in COE were 1.35-2.81%. 3. The index components of PAHs were fluoranthene and pyrene. Their correlation coefficient to total PAHs were 0.96, 0.95, respectively. 4. The particulate PAHs were sampled by filter and gaseous PAHs by adsorbent tube. The collection efficiency of glass fiber filter+silver membrane filter was 20% of total amount sampled by filters+adsorbent and PTFE membrane filter 50%. Adsorbent tube must be attached to the filter to collect light and small PAH components. 5. The generation of acenaphthene and indeno (1,2,3-cd) pyrene were low and concentrations of fluorene and anthracene were $20-40ug/m^3$ throughout coking time. Other PAH eoncentrations were sometimes high. The generation of PAHs was low at 4-6 hours of coking time. The gaseous PAHs were generated earlier than particulate PAHs.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.1
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• pp.43-62
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• 1998

This study was carried out to investigate the influence of different sampling methods on the measured concentrations of polycyclic aromatic hydrocarbons (PAH) both in the vapor and particulate phases, and to evaluate the effects of ambient temperature and sampling duration on the losses of PAH associated with particle samples due to volatilization. The experimental protocol of this study is consisted of two parts. The first part is related to the comparison of PAH concentrations measured by 4 different sampling systems, each of which involves different sampling principles for comparison purposes, including a medium-volume sampler with XAD-2 adsorbent, a high-volume sampler with polyurethane foam (PUF), two identical low-volume samplers: one with XAD-2 and the other with PUF, respectively. The second part of this study is to quantitatively estimate the losses of particulate PAH samples by volatilization during sampling, using two identical low-volume samplers: one was used for changing the filters every 3 hrs, 6 hrs, 12 hrs, and 24 hrs sampling, while the other was maintained for continuous 48 hours sampling without changing the filter. The concentrations of volatile PAH including 2-3 rings appeared to be significantly affected by the type of adsorbent. Measured levels of these lower-molecular weight PAH by XAD-2 adsorbent were much higher than those by PUF for both high-volume and low-volume sampling. PUF was found to give rise to unknown components that interfered with the PAH analysis, even after extensive clean-up. In addition, the retention efficiency of PUF for lower molecular weight PAH was subject to a large variation, being significantly influenced by sampling conditions such as ambient temperature. However, the effect of sampling methods with different adsorbents on the measured levels of semi-volatile compounds including 4 rings PAH such as fluoranthene, pyrene, BaA and chrysene, was not so much significant as more volatile PAH compounds. It was also clear from this study that volatilization losses of the semi-volatile PAH collected on the filters were inevitably occurred during prolonged sampling, and hence the results obtained from conventional sampling methods may not be expected to yield an accurate distribution of PAH between the vapor and particulate phases.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.41-46
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• 1992

To perform a long-term ambient sampling study at a residential site, an air sampler was constructed to collect 24-hour integrated air samples suitable for the volatile organic compounds (VOCs) analysis. It includes an esthetically acceptance due to proximity to homes, as fell as providing the required sampling specifications. The VOCs sampler accomodates four 5/8 "stainless steel(SS) traps packed with adsorbent(Tenax) and is capable of four flow rates in the range of 5 to 50 cc/min. Sintered metal filters(10 micrometer) were directly connected to the inlet of the trap adapters. Additional specifications include: 1) constructed of organically inert materials, 2) weatherproof, 3) battery operated, 4) collecting of VOCs at a breathing zone level, and 5) quiet operation with micro diaphragm pumps wrapped by the sponge. The pump/battery system was separated from the sampling shelter. Sound levels measured for this system were below permissible sound levels (NJDEP) at a residential site. The sampler has been successfully operated at both ground level in a residential area and on the roof of a one story elementary school.hool.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.310-316
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• 2012

The chromaticity of polyethylene glycol (PEG) generated from the recyling of a silicone slurry waste was improved by using activated carbon powder and a carbon filter. The color change of the PEG waste was investigated by changing the amount of adsorbent, adsorption time and temperature. The surface area of activated carbon did not have a significant impact on improving the color of the PEG waste. According to the results for the APHA color variation of the PEG waste changing the amount of the carbon adsorbent, the optimal usage to achieve the low APHA value was 100~150 mg-C/g-PEG. From the investigatnion on the effect of the adsorption temperature range from $25^{\circ}C$ to $100^{\circ}C$, it was found that the optimal temperatures were $40{\sim}50^{\circ}C$ in terms of achieving the lowest APHA value. The variation of the APHA color was investigated by changing the operation condition of the activated carbon filters. The use of ACF was a good way to enhance the chromaticity of the PEG waste. As a result, the APHA value of the PEG waste (APHA=53 at the initial waste) was reduced to be 10 through the ACF purification. It was also confirmed that the performance of the used carbon adsorbent can be recovered by the washing with purified water.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.3
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• pp.67-72
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• 2024

This study developed a dry composite module-type deodorization facility with Twisting airflow changes and two forms (catalyst, adsorbent) within one module. Experiments were conducted to evaluate the reduction efficiency of odor substances C₈H₇N and C₉H₉N. The device combines UV oxidation using TiO₂, catalytic oxidation using MnO₂, and adsorption using A/C in five different methods. Data analysis of experimental results utilized the statistical package program Python 3.12. The program applied frequency analysis of odor removal efficiency, one-way ANOVA, and post-hoc tests, with statistical significance determined by p-value to ensure reliability and validity of the measurements. Results indicated that the highest removal efficiency of C₈H₇N and C₉H₉N was achieved by the UV+A/C method, suggesting the superior effectiveness and efficiency of the developed device. Combining multiple processes and technologies within one module enhanced odor treatment efficiency compared to using a single method. The device's modularity allows for flexibility in adapting to various sewage treatment scenarios, offering easy maintenance and cost-effective deodorization. This composite reaction module device can apply multiple technologies, such as biofilters, plasma, activated carbon filters, UV-photocatalysis, and electromagnetic-chemical systems. However, this study focused on UV-photocatalysis, catalysts, and activated carbon filters. Ultimately, the research demonstrates the practical applicability of this innovative device in real sewage treatment operations, showing excellent reduction efficiency and effectiveness by integrating UV oxidation, TiO₂ photocatalysis, MnO₂ catalytic oxidation, and A/C adsorption within a modular system.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.500-509
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• 2009

Passive samplers have been used for many years for the sampling of organic vapors in work environment atmospheres. Currently, all passive samplers used in domestic occupational monitoring are foreign products. This study was performed to evaluate variable parameters for the development of passive organic samplers, which include the geometry of the device and diffusive length for the sampler design. Four prototype diffusive lengths; A-1(4.5 mm), A-2(7.0 mm), A-3(9.5 mm), A-4(12.0 mm) were tested for adsorption performances to a chemical mixture (benzene, toluene, trichloroethylene, and n-hexane) according to the US-OSHA's evaluation protocol. A dynamic vapor exposure chamber developed and verified by related research was used for this study. The results of study are as follows. The results in terms of sampling rate and recommended sampling time test indicate that the most suitable model was A-3 (9.5 mm diffusive lengths on both sides) for passive sampler design in time weighted average (TWA) assessment. Sampling rates of this A-3 model were 45.8, 41.5, 41.4, and 40.3 ml/min for benzene, toluene, trichloroethylene, and n-hexane, respectively. The A-3 models were tested on reverse diffusion and conditions of low humidity air (35% RH) and low concentrations (0.2 times of TLV). These conditions had no affect on the diffusion capacity of samplers. In conclusion, the most suitable design parameters of passive sampler are: 1) Geometry and structure - 25 mm diameter and 490 $mm^2$ cross sectional area of diffusion face with cylindrical form of two-sided opposite diffusion direction; 2) Diffusive length - 9.5 mm in both faces; 3) Amount of adsorbent - 300 mg of coconut shell charcoal; 4) Wind screen - using nylon net filters (11 ${\mu}m$ pore size).