• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.574-579
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• 2005

Optimal management of indoor air quality in a confined pig house, especially in winter, is indispensable for preventing infectious respiratory disease to workers and animals. This study was performed to elucidate the correlation of aerial contaminants and climate factors in a confinement. It was observed that indoor air contaminants ion in the confinement was the highest at 2:00-5:00 pm in a day, followed by 8:00-11:00 pm and 8:00-11:00 am. This was attributed to the increase of pig activities in the afternoon. The concentration of total dust and total airborne bacteria was found to have a significant correlation with temperature and relative humidity (p<0.05). Correlation of total dust and total airborne bacteria, total dust and ammonia, and total dust and odor were shown statistically significant at 95% confidence level. In conclusion, temperature and total dust concentration correlated significantly with all the parameters except for hydrogen sulfide ($H_2S$). This could be explained by the fact the dryness of pig feces by increase of interior temperature and resuspension of feed deposited on the floor by the pig activity, resulted in high generation of dust which adsorbed and carried the airborne bacteria and odor compounds in a confined pig house. It was proved that the adsorptive capacity of dust with ammonia ($NH_3$) was higher than that with hydrogen sulfide ($H_2S$).

• 미생물학회지
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• 제7권3호
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• pp.115-124
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• 1969

The mash of Takjoo, Korean flour wine, is fermented through two brewing processes ; the primary brewing process to saccharify and the main one to produce ethyl alcohol. The activities of acid proteinase (pH3), weak acid proteinase (pH 6), and alkaline proteinase (Ph 80 on the processes are determined with time by the Folin phenol method as a strength of casein digestion. Hydrogen ion concentration, the content of total organic acids, protein, free amino acids and oligopeptides, which effect the activities of proteinase, are also measured. The results are briefly summarized as follows : 1. In general, the activities of acid proteinase and weak acid proteinase in the mesh of primary brewing process are stronger than those in main brewing process. 2. The activities of acid proteinase are remarkably stronger than those of weak acid proteinase in both processes. It reveals that they decrease slowly through the fermentation. Activities of alkaline proteinase are weaker than others. 3. As the raw materials are mixtured, the total amount of organic acids is equivalent to 0.150 mg/ml acetic acid in the mesh of primary brewing process and 0.02 mg/ml acetic acid in the main one. They increase gradually with time. 4. Hydrogen ion concnetration shows 3.9 in the mesh of main brewing process and 3.28 in the primary one. They increase to the maximum in 60-72 hrs., and decrease since 108 hrs. 5. The content of crude protein shows 66.90mg/ml in the mesh of main brewing process, while shows 64.29mg/ml in the mesh of primary one. they decrease slowly with time. it seems that a small content of crude protein, as a substrate, converts into amino acids and soluble nitrogen compounds by proteinase. 6. The content of free amino acids and oligopeptides shows 0.36 mg/ml in the mesh of primary brewing process and 0.24mg/ml in the main brewing process. It is evident that the reason they increase continuously through the fermentation is the effect of proteinase. 7. According to the results, the strong activities of proteinase in primary brewing process has been derived from the decrease of hydrogen ion concentration due to the production of organic acids.

• Journal of Chest Surgery
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• 제12권4호
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• pp.395-402
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• 1979

Intracellular pH was determined by distribution of 5.5-dimethyl-2,4-oxazolidlnedione [DMO]in the skeletal muscle of dogs before and after lactic acidosis induced by intravenous infusion of lactic acid solution. After infusion of lactic acid solution arterial pH decreased from 7.40 to around 7.12 [P<0.001]and metabolic acidosis was induced. However, dose-pH change response was not proportional as in the case of hydrochloric acid infusion. During lactic acidosis, intracellular pH changed very little except when venous blood $pCO_2$ increased significantly. The decrease of intracellular pH in lactic acidosis might be due primarily to the increase of intracellular $pCO_2$. And during lactic acidosis, change of extracellular pH was larger than that of intracellular pH, and this was also the case of change In hydrogen Ion concentration in extracellular and intracellular fluid. The fact was estimated that exogenous lactic acid transported into the cell does not contribute to pH change by the participation in the metabolism. Change in plasma potassium Ion concentration was not eminent as metabolic acid-base disturbances by other origin, and changing pattern of Hi/He ratio was not same as Ki/Ke ratio. In spite of no changes in extracellular potassium ion concentration after exogenous lactic acidosis total amount of potassium ion in extracellular fluid increased from 12.62mEg to 18.26mEg [P< 0.05].

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.408-412
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• 2004

A total of 23 springs distributed in the southern and northern sides of Mt. Hala in Jeju Island were seasonally sampled and analyzed for their major ion chemistry and oxygen and hydrogen isotope compositions to investigate their hydrogeochemical and isotopic characteristics. Dissolved ion concentrations of the south-side springs slightly increase with decreasing altitude. This indicates that dissolved ion concentrations of groundwater recharged at higher altitudes increase by water-rock interaction during the downgradient migration of groundwater through highly permeable volcanic aquifer. Dissolved ion concentrations of the north-side springs also slightly increase with decreasing altitude, but dramatically increase at ～300 m.a.s.l. This may indicate a sudden input of contaminants to the north-side groundwater system around ～300 m.a.s.l. Springs located in areas above ～300 m.a.s.l. have very low concentrations of dissolved ions, showing little seasonal variations. Whereas springs located in areas below ～300 m.a.s.l. show a big seasonal variation in the concentration of dissolved ions. Seasonal variation of oxygen isotope compositions of springs is ～3$\textperthousand$ for high-altitude springs (～1700 m.a.s.l.) and is ～2$\textperthousand$ near shore, indicating an attenuation of the variation through mixing with other groundwater bodies during migration.

• 한국산학기술학회논문지
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• 제9권6호
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• pp.1768-1774
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• 2008

PWR 정지화학 조건에서 모사실험하여 니켈페라이트 입자의 거동을 조사하였다. 농도가 Li 0.1 ppm, B 2000 ppm인 모사실험 용액의 온도는 $300^{\circ}C$에서 $0.625^{\circ}C/min$의 비율로 $150^{\circ}C$까지 감소시킨 후 일정 시간 동안 $150^{\circ}C$를 유지하였고 이때의 압력은 2500psi 이하로 유지하였다. 수소 농도 5, 15, 25 cc/kg $H_2O$ 일 때 온라인으로 입자 분포를 측정하였고 용해된 니켈 농도도 분석하였다. 실험결과 온도 감소 시 세 가지 수소 농도일 때 모두 총입자 수는 큰 변화가 없었다. 그러나 온도가 감소하고 일정하게 유지될 때 입자는 작아졌다. 입자 크기 분포 변화의 정도는 $H_2$ 15cc/kg $H_2O$ 일 때가 가장 크게 나타났다. 니켈 이온의 농도는 온도가 감소하고 수소 15 cc/kg $H_2O$ 일 때 증가하였다. 이 결과 니켈 페라이트는 온도 변화 시, 수소 15 cc/kg $H_2O$ 일 때 불안정 한 것으로 보여 진다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권4호
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• pp.387-394
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• 2013

As the feature size of integrated circuits continues to decrease, the challenge of achieving an oxidation-free exposed layer after photoresist (PR) stripping is becoming a critical issue for semiconductor device fabrication. In this article, the hydrogen plasma characteristics in direct plasma and the PR stripping rate in remote plasma were studied using a $120{\Phi}$ cylindrical inductively coupled plasma source. E mode, H mode and E-H mode transitions were observed, which were defined by matching the $V_{rms}$ and total impedance. In addition, the dependence of the E-H mode transition on pressure was examined and the corresponding plasma instability regions were identified. The plasma density and electron temperature increased gradually under the same process conditions. In contrast, the PR stripping rate decreased with increasing proportion of $H_2$ gas in mixed $H_2/N_2$ plasma. The decrease in concentration of reactive radicals for the removal of PR with increasing $H_2$ gas flow rate suggests that NH radicals have a dominant effect as the main volatile product.

• Journal of Ginseng Research
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• 제5권1호
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• pp.73-84
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• 1981

Effect of environmental factors and host on the growth and outbreak of various ginseng diseases was reviewed Environmental lectors included hydrogen ion concentration, moisture content, temperature, nutrition, and microbiol populations. Age of the ginseng plants in relation to several ginseng disease occurrence was also included in order to formulate the effective control measure for ginseng diseases. Damping-off caused by Rhizoctonia, Pythium, and Phytophthora, greymold by Botrytis, sclerotinia by Scleretinia, and phytophthora blight caused by Phytophthora were usually prevalent during the early growing season of ginseng when temperature is below 20$^{\circ}C$, while anthrac se caused by Colletotrichum, alternaria blight by Alternaria, and bacterial soft rot by Erwinia were so during the latter growing season when temperature is above 25$^{\circ}C$. However, the root rot incited by Fnarium and Cylindrocarpon caused severe damages throughout the growing season. Growth range of the temperature for a pathogen was highly related to the corresponding disease outbreak. Hydrogen ion concentration was highly related to the outbreak of sclerotinia, root rot, and red rot. Most severe outbreak of those diseases where the soil acidity was pH 4.7, pH 6.5- 7.5, and pH6.0-6.5, respectively. Nitrogen content in the soil was also related to outbreak of root rot and red rot. More red rot occurred where NH,-nitrogen is above 30 ppm and more root rot obtained when excessive nitrogen fertilizer applied. Yellow necrosis apparently was related to magnesium especially its ratio with potassium or calcium content in a soil. Fusarium Population showed significant .relations to missing rate of ginseng Plants in a Implanting ginseng field, while that of total bacteria showed similar relations in all ginseng field, However, in six year old ginseng fields, the more the Streptomyces population was, the less the Fusarium obtained. Consequently, less missing rate observed in a field where Streptomyces population was high. Damping-off, root rot, Rhytophthor a blight were mose severe on the nursery and on 2-3 years old ginseng plants, whereas sclerotinia, and grey cod, alteraria blight, anthracnose were severe on 4-6 years old ginseng plants. Root rot caused by Fusarium and Erwinia, however, was also severe regardless of the age of the plants when the roots were injured. Therefore, for the effective control of ginseng root rot most careful control of the disease during the early year should be rendered.

• 한국해양환경ㆍ에너지학회지
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• 제14권3호
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• pp.205-211
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• 2011

해수 중의 수소이온농도(pH)와 총알칼리도(TA) 측정 방법에 대한 선상 비교 연구가 동해 표층에서 저층에 이르는 약 550개의 실제 해수 시료에 대해 이루어졌다. 분광광도법과 전위차법에 대한 pH의 비교가 이루어졌으며, 두 방법에 의한 해수의 pH는 전반적으로 잘 일치하였으나, pH가 낮은 심층의 경우 피펫을 사용한 분광법에 의한 값이 전위차법 보다 높은 값을 보였다. 그러나 피펫을 사용하지 않은 분광법과는 두 방법의 정밀도 내에서 동일한 값을 보였다. 이는 피펫에 의해 해수 내의 이산화탄소가 제거되면서 시료 내의 pH를 증가시키는 것으로 판단된다. TA 측정법의 비교를 위해 폐쇄 용기를 이용한 전위차법과 개방 용기를 이용한 전위차법이 사용되었으며, 개방형 용기를 사용했을 때의 값이 폐쇄형 용기를 사용했을 때의 값에 비해 약 5~10 ${\mu}mol\;kg^{-1}$ 작은 값을 보인다. 이는 폐쇄형 용기를 사용했을 때, 적정 도중에 발생하는 이산화탄소가 용액 속에 남아 적정액인 염산 이외의 산을 용액 속에 추가하는 효과를 내기 때문으로 판단된다. 따라서 pH혹은 TA의 분석에 있어서 본 연구에서 비교한 어느 방법을 사용할 수도 있지만 각각의 방법에 대해 특별히 요구되는 주의를 기울일 때 만족할 만한 분석결과를 얻을 수 있다.

• 신재생에너지
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• 제18권4호
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• pp.1-11
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• 2022

Landfill gas (LFG) generation characteristics in a construction waste landfill zone (block E) and mixed landfill zone (block A) were analyzed. During the period from October 2018 to April 2022, a total of 936×10³ and 1,001×10³ tons of waste were disposed in block E and block A, respectively. Out of this, 27.1% and 55.6% were biodegradable waste in block E and block A, respectively. The landfill masses of the two blocks were converted to be comparable. Then, the biodegradable waste and organic carbon were estimated by element analysis, biodegradable carbon by biochemical methane potential experiment (DC), and sulfate ion by acid decomposition. Results showed that biodegradable waste, organic carbon, biodegradable carbon, and sulfate ions in block A were 2.1, 1.6, 5.2, and 0.4 times greater than those in block E, respectively. The amount of LFG generated by block A was 4.8 times greater than that by block E. The average concentrations of methane (CH₄) were 60.8% and 60.9% in block E and block A, respectively, which were unrelated to the nature of disposed waste. The average concentrations of hydrogen sulfide (H₂S) were significantly high in block E (4,489 ppm) and block A (8,478 ppm). As the DC/SO₄^2- of block E and block A were 0.35 and 4.56, respectively, increase in DC/SO₄^2- caused increase in not only the total amount but also the concentration of H₂S generated.

• 대한화학회지
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• 제46권6호
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• pp.509-514
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• 2002

정지흐름분석법을 이용하여 화학발광법으로 수용액 중의 Fe(II)와 Fe(III)을 분리 정량하는 방법에 대하여 연구하였다. 이 방법은 lucegenin과 $H_2O_2$ 혼합용액에 Fe(III)이온을 첨가하였을 때 화학발광의 세기가 증가하는 것을 기초로 하였다. KO H, $H_2O_2$ 및 Fe(III)의 가리움제로 이용한 citric acid의 농도와 시료의 주입속도가 화학발광의 세기에 미치는 영향을 조사하였다. 전체 철의 정량을 위하여 구한 [$H_2O_2$], [KOH] 및 흐름속도의 죄적조건은 각각 4.0M, 2.0M, 및 3.5mL/min 이었고, 이러한 최적조건 하에서 얻은 검정곡선에서 직선성이 성립하는 범위는 1.0${\times}10^{-6}$M에 서 1.0${\times}10^{-4}$M이었고, 상관계수는 0.996, 검출한계는 1.0${\times}10^{-7}$M이었다. Fe(III)이온의 정량을 위하여 구한 [$H_2O_2$], [KOH], [citric acid] 및 흐름속도의 최적조건은 각각 4.0M, 2.0M, 0.01M 및 3.5mL/min이었고 이러한 최적조건 하에서 얻은 검정곡선에서 직선성이 성립하는 범위는 1.0${\times}10^{-6}$M에서 1.0${\times}10^{-4}$M이었고, 상관관계수는 0.997, 검출한계는 5.0${\times}10^{-7}$M이었다.