• Title/Summary/Keyword: Dew

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Airborne Nicotine Concentrations in Harvesting and the Processing of Tobacco Leaves (담뱃잎 수확 및 가공 과정에서 공기 중 니코틴농도)

  • Park, Sung-Jun;Kim, Jong-Seuk;Kim, Jik-Su;Lee, Kwan;Lim, Hyun-Sul
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.1
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    • pp.47-52
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    • 2010
  • Green tobacco sickness (GTS) is known as an occupational disease among tobacco harvesters, and a form of acute nicotine intoxication by the absorption of nicotine through the skin from the wet green tobacco plant. On the assumption that GTS may occur by inhalation as well as absorption of nicotine, we measured the airborne nicotine concentration in tobacco field and the processing room of tobacco leaves. We measured the airborne nicotine concentrations in the tobacco field and processing room between 13 and 30 July 2008. All sampling and analyses of airborne nicotine were conducted according to the manual of analytic methods of NIOSH 2551, and we sampled 2 times at 11 points in the tobacco field by area sampling. The sampling in the processing room of tobacco leaves was conducted at 3 points, and earlymorning dew was collected from the tobacco by wringing the moisture into specimen bottles. The airborne nicotine concentration [geometric mean (geometric standard deviation)] in the tobacco field in the P.M. was higher [49.2 mg/$m^3$ (1.3)] than the A.M. concentration [43.4 mg/$m^3$ (1.4)]. Similarly, the nicotine concentration in the processing room of tobacco leaves was 224.4 mg/$m^3$ (1.2), and the concentration of nicotine in the dew was 64.7 mg/${\ell}$ (1.7). Based on our results, the airborne nicotine concentration in the tobacco field and the processing room of tobacco leaves were 100 and 400 times higher than the occupational recommended values (TLV-TWA of 0.5 mg/$m^3$), respectively. In the future, it is hoped that epidemiologic studies and environmental measurements will be conducted for GTS which occurs by inhalation of nicotine. If GTS is confirmed to occur by inhalation of nicotine, respiratory and dermal protective equipment must be distributed.

The study on corrosion of the inner area of closed box-girder for unpainted weathering steel bridges (무도장 내후성 강 교량의 밀폐형 박스거더 내부의 부식에 대한 고찰)

  • Ma, Seung-Hwan;Noh, Young-Tai;Jang, Gun-Ik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2391-2400
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    • 2015
  • Weather proof steels are used for steel bridges due to its high corrosion resistance under atmospheric conditions. However, instead of forming stabilized rust layers, general rust occurs on weather proof steels under high humidity condition close to seawater or shady places. In Japan, therefore, they perform rust stabilization treatment instead of unpainted treatment due to severe atmospheric conditions. However, most of domestic weather proof steels were constructed unpainted in the form of closed box-girder, which makes the periodical repetition of dry and wet hard to occur. For the steel bridges constructed on the Han river, the evaporation of water, dew condensation due to temperature change, and stagnant water due to rain affect harmfully on the formation of passive film on weather proof steels. Thus, in this research, in order to analyze corrosion properties inside the closed box-girder for the unpainted weather proof steel bridge in the waterworks safety zone, multiple ways of analysis such as observation with eyes, cellophane-tape test, steel thickness measurement, surface corrosion potential measurement, electron microscope analysis, and X-ray diffraction analysis of the rust were performed. As a result, unstable rust layer was observed inside the closed box-girder, and severe corrosion was observed on the top and bottom of the flanges due to the effects of stagnant water caused by rain, dew condensation, and de-icing materials.

An Experimental Study on the Effect of Air Temperature and Humidity on Humidification Performance of the Humidifying Element Used for Air Conditioning (공기 온습도가 공조용 가습 소자의 가습 성능에 미치는 영향에 대한 실험 연구)

  • Kim, Nae-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.2
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    • pp.732-740
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    • 2019
  • Evaporative humidification using a humidifying element is widely used for humidification of a building or a data center. The performance of a humidifying element is commonly expressed as humidification efficiency, which is used independent of air temperature, humidity and water temperature. In this study, a series of tests were conducted at two air conditions (data center and commercial building) using two different humidifying elements (cellulose/PET and Glasdek) changing the frontal air velocity and water temperature. Results showed that the measured humidification efficiency was dependent on the air condition and water temperature. In fact, even dehumidification occurred at the inlet of the humidifying element at the air condition of commercial building. The reason was due to the inlet water temperature, which was lower than the dew point air temperature. As the difference between the inlet water and the dew point air temperature increased, the humidification efficiency decreased. This suggest that proper thermal model should account for the inlet region, where the amount of moisture transfer may be different from the other part of the humidification element. A simple analysis on the thermal performance of the cellulose/PET humidification element showed that the Sherwood number was adequately predicted, whereas the friction factor was ovepredicted, probably due to the simplification of the channel geometry and the neglection of the water film on the element surface.

Study on the Change of Relative Humidity in Subsea Pipeline According to Drying Method (건조 공법에 따른 해저 파이프라인 내부 상대습도 변화 특성 연구)

  • Yang, Seung Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.2
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    • pp.406-413
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    • 2022
  • The subsea pipeline pre-commissioning stage consists of the following processes: Flooding, Venting, Hydrotesting, Dewatering, Drying, and N2 Purging. Among these processes, drying and nitrogen purging processes are stipulated to reduce and maintain the relative humidity below dew point to prevent the generation of hydrate and the risk of gas explosion in the pipeline during operation. The purpose of this study is to develop an analysis method for the air drying and nitrogen purging process during pre-commissioning of the subsea pipeline, and to evaluate the applicability of the analysis method through comparison with on-site measurement results. An analysis method using Computational Fluid Dynamics (CFD) was introduced and applied as a method for evaluating the relative humidity inside a subsea pipeline, and it was confirmed that analysis results were in good agreement with the on-site measurement results for the air drying and nitrogen purging process of the offshore pipeline. If the developed air drying and nitrogen purging analysis method are used as pre-engineering tools for pre-commissioning of subsea pipelines in the future, it is expected to have a significant impact on the improvement of work productivity.

Development of a Drain-Type Electronic Dehumidifier Using Thermoelectric Element (열전소자를 이용한 배수형 전자제습기 개발)

  • Kang, Deok-Hong;Kim, Seong-Hwan;Kim, Ki-Hong
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.3524-3528
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    • 2007
  • In this study, the Peltier effect was applied to eliminate moistures in the air enclosed by a cabinet. We have developed the new electronic dehumidifier which has a new function of automatically evaporating the condensed water inner cabinet into the outside air. To obtain this function, the processes of dehumidification is that it condensed the moistures on the cold side heat sink and drained it into the hot side heat sink by the both gravitational and capillary forces and the droplets on the hot side heat sink surface was evaporated into the air outside the cabinet by the heat conducted through the hot side heat sink surface and the forced heat convection through the fan for cooling hot side heat sink. Compared to existing electronic dehumidifiers, this manufactured one showed a good performance that the electric power consumption for the same dehumidifying quantity was reduced by 50% compared with that of existing ones.

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A Development of the Color Story and Color Scheme for Domestic Makeup Product Based on the Personal Color Images (개인의 색채이미지 유영에 의한 국내 색조화장품의 스토리 개발과 색채 계획)

  • Kim Youngin;Joo Miyoung;Lee Hyunjoo;Kim Heeyeon
    • Journal of the Korean Society of Costume
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    • v.55 no.6 s.96
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    • pp.1-14
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    • 2005
  • The purpose of this study is to examine the makeup color range for developing the new makeup product line of domestic cosmetic brand, and suggest the special color stories and color palettes appropriate to characteristics of brand image For this study, personal color images are analyzed and classified through the literature survey of Korean womens' skin rotor like korean PCDS and japanese PCS. Also, a total of 3879 colors were selected from the 18 cosmetic brands and were analyzed by hue/tone color system. Based on the color analysis, the color range for makeup products are determined, and the typical colors of 4 personal color images are suggested. As a results, personal color images are classified into 4 types: DEW of p, lt, b tone; FLASH of s, v tone; MIST of ltg, g, sf, d tone; TERRA of dk, dkg, dp tone. we developed the color stories through five senses and lifestyles based on the consumers' emotion, and the rotor palettes suitable to each type of personal color images are developed.

DRYING CHARACTERISTINCS OF THIN-LAYERS OF WHEAT AND BARLEY AT NEAR-AMBIENT TEMPERATURE

  • Sun, Da-Wen;J.J.Woods
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.896-905
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    • 1993
  • Thin-layers of wheat and barley are dried at near-ambient temperatures(3.5$^{\circ}C$ -5$0^{\circ}C$) in order to obtain the intrinsic drying data. The well established apparatus was modified to enable it to record all the sample weight data in still air by using a purpose -built automatically controlled sliding valve. The air could be diverted in less than 0.5seconds and a 7 second period was required to attain a steady weight reading. With this apparatus, very smooth drying curves were obtained. The data of sample weight , drying temperature and dew point temperature wee recorded continuously . The drying process was terminated when the moisture content change in 24 hours was less than 0.004 d.b. This was achieved by drying a sample for about a week . The final points were recorded as the dynamic equilibrium moisture content(EMC). The drying data were than fitted to the exponential Newton model and the dynamic EMC data were fitted to the Modified-Chung-Pfost Model . All the fitted parameters are given and comparison is made with previous published data. The comparisons who that the current drying constants are lower than the previous data, the dynamic EMC data obtained for wheat and barely agree with the previous data. The results show that to obtain the drying constant in the exponential Newton model, adequate drying time is necessary.

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The Research of Wang HaoGu's Eum Syndrom Theory (왕호고(王好古)의 음증학설(陰證學說)에 대한 연구(硏究))

  • Cho, Byung-Il;Kim, Yong-Jin
    • Journal of Korean Medical classics
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    • v.20 no.2
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    • pp.125-135
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    • 2007
  • Eum Syndrom include symptoms which is because by the cold thingsand by the infection of SamEum of TaeEum, SoEum, GualEum in Treatise On Exogenous Febrile Diseases(傷寒論). After Wang HoGo, many medical people had proceed the research of Eum Syndrom, but recently, we have almost never or no nothing research about that. So, I want to make modern base of Eum syndrom, and researched mainly for the "YinZhengLueLi". That can be summarized like below. Eum Syndrom shows firstly red face, tremor, waist-and-leg heaviness, lastly body heaviness, fatigue, narcolepsy, congestion of the pupils because of from exogenous attack of wind-cold, impairment of spleen due to Cold things, and dew and mist and rain and damp's invation by mouth and nose, greedy of sexual desire, So, in the diagnosis of Eum Syndrom, we have to look over precisely the color and pulse, especially, by pulse. We can know that, he used the prescription which are have heating kidney function, Byuklyuksan, Jungyangsan, Huahamsan, Huiyangdan, Baneumdan etc, and the prescription which are have strengthening spleen and kidney, Bujasan, Yukgyesan, Bakchulsan etc. So, we can know that he was very interested in deficiency and cold of kidney's function. While, he newly made the prescriptions of Sinchultang, Bakchultang, Huanggitang, Jujunghuan, and he used various prescriptions.

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Status of PM10 as an air pollutant and prediction using meteorological indexes in Shiraz, Iran

  • Masoudi, Masoud;Poor, Neda Rajai;Ordibeheshti, Fatemeh
    • Advances in environmental research
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    • v.7 no.2
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    • pp.109-120
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    • 2018
  • In the present study research air quality analyses for $PM_{10}$, were conducted in Shiraz, a city in the south of Iran. The measurements were taken from 2011 through 2012 in two different locations to prepare average data in the city. The averages concentrations were calculated for every 24 hours, each month and each season. Results showed that the highest concentration of $PM_{10}$ occurs generally in the night while the least concentration was found at the afternoon. Monthly concentrations of $PM_{10}$ showed highest value in August, while least value was found in January. The seasonal concentrations showed the least amounts in autumn while the highest amounts in summer. Relations between the air pollutant and some meteorological parameters were calculated statistically using the daily average data. The wind data (velocity, direction), relative humidity, temperature, sunshine periods, evaporation, dew point and rainfall were considered as independent variables. The relationships between concentration of pollutant and meteorological parameters were expressed by multiple linear regression equations for both annual and seasonal conditions SPSS software. RMSE test showed that among different prediction models, stepwise model is the best option.

An experimental study of frost forming on the horizontal cylinder under cross flow (직교유동 내에 놓인 수평 실린더에서 서리 생성에 관한 실험적 연구)

  • 이윤빈;노승탁
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.4
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    • pp.448-456
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    • 1999
  • Variations of thickness and effective thermal conductivity of frost forming on the horizontal] cylinder with respect to time were measured under cross flow. The local heat flux around the cylinder was determined by measuring the radial temperature distribution in the cylinder having small holes drilled axially in which T-type thermocouples were inserted, then by using one dimensional cylindrical heat conduction equation. The thickness and the surface temperature of the frost layer around the cylinder were measured periodically while developing the frost. Each experiment was peformed by varying the Reynolds number, the temperature, and the humidity condition. Specially the dew point temperature of the most cases was below the freezing point. Experimental data showed that the frost layers on the front and the rear surface were thicker than those on the top and the bottom one which was near the separation point. The thickness and effective thermal conductivity of the frost layer were affected by inlet air velocity, temperature, and humidity. Moreover, the effective thermal conductivity and the effective thermal resistance increase with respect to time.

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