• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.85-95
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• 2018

In this research, a biofilter system equipped with a biofilter process and a humidifier composed of a fluidized aerobic and an anoxic reactor, was constructed to treat odorous waste air containing hydrogen sulfide, ammonia and VOC, frequently generated from pig and poultry housing facilities, compost manufacturing factories and publicly owned facilities. Its optimum operating condition was revealed and discussed. In the experiment of complex feed, the ammonia of fed-waste air was removed by ca. 75% and more than 20% at the stage of the humidifier and the biofilter, respectively. The toluene of the fed-waste air was removed by ca. 20% and more than 70% at the stage of the humidifier and the biofilter, respectively. Therefore the water-soluble ammonia and the water-insoluble toluene were treated mainly at the stage of the humidifier and the biofilter, respectively. In addition, hydrogen sulfide was almost absorbed at the stage of the humidifier so that it was not detected at the biofilter process. In the experiment of ammonia-containing feed, the ammonia of fed-waste air was removed by ca. 65% and 35% at the stage of the humidifier and the biofilter, respectively. Its removal efficiency of ammonia at the stage of the humidifier was 10% less than that in the experiment of complex feed, due to no supply of such carbon source as toluene required in the process of denitrification. In the experiments of complex feed, ammonia-containing feed with and without (instead, glucose) the addition of yeast extract, the absorption rates of ammonia-nitrogen were ca. 0.28 mg/min, 0.23 mg/min and 0.27 mg/min, respectively. The corresponding denitrification rates in the anoxic reactor were 0.42 mg/min, 0.55 mg/min and 0.27 mg/min, respectively. In addition, in the modeling of bubble column(the fluidized aerobic reactor of the humidifier) process, the value of specific surface area(a) of bubbles multiplied by enhanced mass transfer coefficient (E $K_y$) was evaluated to be 0.12/hr.

• Journal of Korean Academy of Nursing
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• v.3 no.3
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• pp.78-96
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• 1973

This study of 855 clinical nurses was conducted using a questionnaire that include tour different scales; the motives of determining their profession, the attitudes toward their profession, the general items, and desire and expectation to their profession and society. The data were analyzed by Chi-Square Test and Percentage. The results of this study included Hypothesis are as follows; The respondents were 855 (78.6%) among 1088 clinical nurses who were employed by General of Educational hospitals through the city of Seoul, Pusan, Taegu, Daejun, Kwangju, and Wonju. 1) a. In the Age Distribution, the majority of respondents were under the age of 30yrs(88.2%) and the minority were above 31yrs(11.2%), and the preponderance of the majority to minority(9:1) was noted. In compared with area, a group above 31yrs old in Seoul (6.9%) was lower than other area (16.3%). b. The types of Educational background were 16.3% in Voc.Tr. School, 66.5% in Diploma and 17.1% in Degree.146 clinical nurses were from the Degree course, and 142 (97.3%) CN among those of them were occupied around Seoul and 4(2.7%) around other area. c. In the Marital Status,71,5% were the unmarried and 28.5% were the married. And compared with the area was 20.4% in Seoul and 41.4% in other area. d. Most common Length of Clinical Experience after graduation was under tile 2yrs (55.4%), 3yrs(14.2%, and 4yrs (6.2%). In compared with area, Seoul (15.3%) was lower than other area (38.1%) above 5yrs of clinical experience, and the preponderance of tile other area to Seoul as 2.5: I was noted. 2) a. Hypothesis 1 was significant relation between the types of Educational Background of the CN and their motives for selection of Nursing, P-value was below 0.01. b. There was a significance on hypothesis 2 (P＜0.01): that was relation between their motives for selection of clinical nursing field after their graduation and the area which they were employed. c. Hypothesis 4 was accepted as significant relation between the level of satisfaction of their clinical experience after their graduation and the types of educational back ground, P-value was below 0.01. d. There was a significance on hypothesis 5(P＜0.01) that was relation between the CN's response about the orientation program and the area which they were employed. e. Hypothesis 6 was retained as significant relation between the area and inservice educational programme of their employed hospital was practising or not. P-value was 0.01. f. Hypothesis 7 was retained as significant relation between the area and the CN's response about the inservice educational programme of their employed. P-value was below 0.01. g. There was a significance on hypothesis 8 (P<0.0l) that was relation between the CN's experience on attending the professional meeting and the area. h. Hypothesis 10 was accepted as significant relation between the response about the present licence system and their educational background. p-value was below 0.01. i. There was a significance on hypothesis 11 (P fO.01) that was relation between the carrying out the regular and delivery vacation and the area. J. Hypothesis 12 was accepted as significant relation between the CN's consideration of the lack of leisure and their marital status. p-value was below 0.01' k. There was a significance on hypothesis 13 (P <0.01) that was relation between the CN's response about their salary and their marital status. l. Hypothesis 14 was significant relation between the most difficulties of CN during their working and the hospital which they were employed. p-value was below 0.01.

• Analytical Science and Technology
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• v.25 no.6
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• pp.447-459
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• 2012

In this study, the emission characteristics of volatile and odorant species released from salted meat product (Spam) was investigated as a function of time. Gas samples released from Spam samples were analyzed for volatile organic compounds (VOC) and sulfur compounds (RSC) at five different times for the elapsed (E) days of 0, 1, 3, 6, and 9 (E-0 to E-9) by GC/MS and GC/PFPD system, respectively. Results indicated that reduced sulfur, aldehyde, and ketone groups were the dominant odorants. Especially, hydrogen sulfide was the predominant in concentration and odor activity value (OAV) during the fresh stage. Its concentration was 1465 ${\mu}g/m^3$ (60.0% of the total mass) in E-0 and 455 ${\mu}g/m^3$ (28.0%) in E-1, while its OAV was 19.4 (78.3%: E-0) and 6.02 (41.7%: E-1). On the other hand, the concentration of acetone showed the maximum values in the decaying stage (E-3: 451 (43.2%), E-6: 369 (64.2%), and E-9: 1150 ${\mu}g/m^3$ (70.2%)). Furthermore, the concentration of 2,3-butanedione was also detected considerably from decaying sample (E-3: 17.6 (1.68%), E-6: 16.1 (2.80%), and E-9: 179 ${\mu}g/m^3$ (10.9%)). However, OAV of acetone was insignificant (<0.01%) in the decaying stage, while that of 2,3-butanedione was relatively high in the range of 1.14-11.6 (14.5-76.2% of ${\Sigma}OAV$). It thus confirmed that the major odorant groups generated from Spam samples changed with the progress of decay such as sulfur (fresh stage), aldehyde (intermediate stage), and ketone compounds (decaying stage).

• Analytical Science and Technology
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• v.22 no.6
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• pp.488-497
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• 2009

In this study, analytical methodology for several organic fatty acids (OFA: propionic acid (PA), butyric acid (BA), isovaleric acid (IA), and valeric acid (VA)) designated as new offensive odorants in Korea (as of year 2010) was investigated along with some odorous VOCs (styrene, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate, and isobutyl alcohol). For this purpose, working standards (WS) containing all of these 13 compounds were loaded into adsorption tube filled with Tenax TA, and analyzed by gas chromatography (GC) system thermal desorber interfaced with. The analytical sensitivities of organic fatty acids expressed in terms of detection limit (both in absolute mass (ng) and concentration (ppb)) were lower by 1.5-2 times than other compounds (PA: 0.24 ng (0.16 ppb), BA: 0.19 ng (0.11 ppb), IA: 0.15 ng (0.07 ppb), and VA: 0.28 ng (0.13 ppb)). The precision of BA, IA, and VA, if assessed in terms of relative standard error (RSE), maintained above 5%, while the precison of other compounds were below 5%. The reproducibility of analysis improved with the aid of internal standard calibration (PA: $1.1{\pm}0.4%$, BA: $10{\pm}0.46$, IA; $12{\pm}0.3%$, VA: $4{\pm}0.1%$), respectively. The results of this study showed that organic fatty acid can be analyzed using adsorption tube and thermal desorber in a more reliable way to replace alkali absorption method introduced in the odor prevention law of the Korea Ministry of Environment (KMOE).