• Title/Summary/Keyword: buffering effect

Search Result 184, Processing Time 0.028 seconds

A study on Etch Characteristics of {Y-2}{O_3}$ Thin Films in Inductively Coupled Plasma (유도 결합 플라즈마를 이용한 {Y-2}{O_3}$ 박막의 식각 특성 연구)

  • Kim, Yeong-Chan;Kim, Chang-Il
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.38 no.9
    • /
    • pp.611-615
    • /
    • 2001
  • Y$_2$O$_3$ thin films have been proposed as a buffering insulator of metal/ferroelectric/insulator/semiconductor field effect transistor(MFISFET)-type ferroelectric random access memory (FRAM). In this study, $Y_2$O$_3$ thin films were etched with inductively coupled plasma(ICP). The etch rates of $Y_2$O$_3$ and YMnO$_3$, and the selectivity of $Y_2$O$_3$ to YMnO$_3$ were investigated by varying Cl$_2$/(Cl$_2$+Ar) gas mixing ratio. The maximum etch rate of $Y_2$O$_3$, and the selectivity of $Y_2$O$_3$ to YMnO$_3$ were 302$\AA$/min, and 2.4 at Cl$_2$/(Cl$_2$+Ar) gas mixing ratio of 0.2 respectively. Optical emission spectroscopy(OES) was used to understand the effects of gas combination on the etch rate of $Y_2$O$_3$ thin film. The surface reaction of the etched $Y_2$O$_3$ thin films was investigated by x-ray photoelectron spectroscopy (XPS). XPS analysis confirmed that there was chemical reaction between Y and Cl. This result was confirmed by secondary ion mass spectroscopy(SIMS) analysis.

  • PDF

Selection of Aquatic Plants Having High Uptake Ability of Pollutants in Raw Sewage Treatment (생활오폐수에 대한 정화력이 높은 수생식물 선발)

  • Kim, Choon-Song;Ko, Jee-Yeon;Lee, Jae-Saeng;Park, Sung-Tae;Ku, Yeon-Chung;Kang, Hang-Won
    • Korean Journal of Environmental Agriculture
    • /
    • v.26 no.1
    • /
    • pp.25-35
    • /
    • 2007
  • Excess runoff contaminated with N and P can impact the quality of downstream water. It has been known that aquatic plants improve the water quality through their intake of organic or inorganic nutrients. This study was conducted to select aquatic plants having high purification ability for nutrient N and P, and mineral nutrients related to EC such as K, Ca, Na, Cl, and $SO_4$ in raw sewage water in greenhouse. We assessed nutrient phytoremediation potential of alien hydrophyte and hydro-crop as well as native landscape hydrophyte to select suitable aquatic plant applied to artificial wetland and buffering site of stream-side. The amount of irrigation water during whole growing period of aquatic plane ranged from 225 L $m^{-2}$ to 444 L $m^{-2}$. Oryza sativa, Typha orientalis, Zizania latifolia, Aster subulatus, Coix lachryma-jobi var. mayuen, Paspalum disdichum var. indutum which had high biomass consumed the large amount of irrigation water over 350 L $m^{-2}$. As a result of analysis of water purification effect N and P content of shoot biomass, and media soil after experiment, Oryza sativa, Zizania latifolia, Aster subulatus, Coix lachryma-jobi var. mayuen, Paspalum distichum var. indutum showed high purification ability about eutrophication elements such as T-N and T-P. It is presented that Pistia stratiotes, Eichhornia crassipes, and Paspalum distichum var. indutum had excellent purification ability about K, Ca, Na, and Cl. Moreover, Paspalum distichum var. indutum greatly removed $SO_4$ in row sewage water.

Effects of Aspergillus oryzae Inclusion on Corn Silage Fermentation

  • Chiou, Peter Wen-Shyg;Ku, Hsiao-Che;Chen, Chao-Ren;Yu, Bi
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.11
    • /
    • pp.1568-1579
    • /
    • 2001
  • This study is aimed at evaluating the effect of Aspergillus oryzae fermentation extract (AFE) on corn silage fermentation characteristics. Trial included two groups of treatments, with or without AFE inclusion in corn ensilage. Sixty corn silage containers, including two treatments with thirty replicates each, were processed in a laboratory scale mini-silo of 21 cm radius by 45 cm height. Three replicate containers were opened and sampled for analysis at 0, 0.5, 1, 2, 3, 4, 6, 10, 18 and 34 days after being ensiled. One silage container from each treatment was installed with a remote controlled electronic thermometer to record the temperature changes. Analysis included silage temperature, pH, fermentation acids, the water-soluble carbohydrates and chemical compositions and the silage protein fractions. Results showed that on the first day, the temperature of the ensiled corn was slightly higher than room temperature, but returned to room temperature on the second day. The pH and concentrations of WSC, ADF, lignin and acetic acid in the AFE treated silage were significantly lower than the control groups (p<0.05). The lactic acid and crude protein on the other hand were significantly higher in the AFE treated silage as compared to the control (p<0.05) at the end of the ensilage period. The DM content was significantly higher (p<0.05) whereas the butyric acid content of the AFE treated silage was significantly lower (p<0.05) than the control at the end of the 34 day ensilage period. Titratable acid and buffering capacity in the corn silage were not significantly different between treatment groups (p>0.05). Ammonia N concentration in the AFE treated silage showed a trend of decrease (p>0.05). NPN and the protein fraction A in both groups increased during the conservation period, but fraction A in the AFE treated corn silage was significantly higher than the control silage (p<0.05). During the conservation period, the AFE treated corn silage showed a trend toward a decrease in fractions $B_1$, $B_3$ and C (p<0.05). The protein fraction B2 showed a trend toward increase in the control group and an inconsistent trend in the AFE treated silage during the ensiling period. The AFE treated silage showed a better Flieg score over the control silage (97 vs. 75) as calculated from the concentrations of lactic acid, acetic acid and butyric acid.

A Study on the Forming Technology of Multi-stage Aircell Filling Valves (다단 에어셀 충진 밸브성형기술에 관한 연구)

  • Kim, Mi-Suk;Park, Dong-Sam
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.12
    • /
    • pp.57-64
    • /
    • 2017
  • Today, due to the environmental regulations regarding air pollution in the EU, the use of EPS (Styrofoam) as the cushioning material in the packaging industry is decreasing. In effect, air cushioning based cushioning materials are rapidly expanding into the market and replacing EPS, due to their excellent buffering ability and environmental friendliness. This is a new selective filling type air filling material manufacturing technology that affords improvements in the amount of raw materials required, its processing and its aesthetic appearance compared to the conventional air filling cushioning materials. In this study, a multi-stage air cell filling valve molding technology is developed based on selective filling technology, which allows packages to be selectively filled in various forms by applying valve forming structure technology. This multi-stage air cell filling valve molding technology is a technique in which a plurality of injection ports are formed by laminating three layers of films, viz. a first injection film, a valve film, and a second injection film having valve ends. In the conventional technology, a separate external air injection path for injecting air into a plurality of connected air bags is needed. However, in the proposed system, an external air injection path is formed inside the air bag, Due to the lack of need for an injection furnace, the raw material and process are reduced and air is injected and then discharged, while the air bag is reduced in length to 63 ~ 66% of its normal value. The outer surface of the outer air injection path is integrated inside by maintaining the original length of the cross section, while the unnecessary folded air is injected into the interior of the air bag, This smart air filling type cushioning material manufacturing technology constitutes a big improvement over the existing technologies.

Calretinin-Containing Neurons in the Deeper Layers of the Hamster Superior Colliculus (햄스터 상구의 deeper layers에서 calretinin이 함유 신경세포)

  • Kim, Ye-Eun;Choi, Jae-Sik;Kim, Hye-Hyun;Yeo, Jin-Yeon;Jeon, Chang-Jin
    • Journal of Life Science
    • /
    • v.16 no.5
    • /
    • pp.750-758
    • /
    • 2006
  • Calcium-binding protein calretinin is thought to play important roles in calcium buffering. Recently, we reported on the distribution, morphology of calretinin-immunoreactive (IR) neurons and the effects of eye enucleation on the immunoreactivity of calretinin in the superficial layers of the hamster superior colliculus (SC). In the present study, we describe the distributions and types of labeled cells and effects of enucleation in the deeper layers by immunocytochemistry. We also compare this labeling to that of GABA, the major inhibitory neurotransmitter in the central nervous system. In contrast to the superficial layers, the deeper layers contained many calretinin-IR neurons which formed two tiers. The first tier, which was very distinctive, was found within the intermediate gray layer. The second tier was found in the deep gray layer. Labeled neurons varied dramatically in morphology and included vertical fusiform, stellate, round/oval, and horizontal neurons. In contrast to the superficial layers, enucleation appeared to have no effect on the distribution of calretinin immunoreactivity in the deeper layers. Two-color immunofluorescence revealed that none of calretinin-IR neurons were labeled with an antibody to GABA. The present results demonstrate that calretinin identifies unique neuronal sublaminar organizations in the hamster SC. The present results also demonstrate that none of the calretinin-IR neurons in the hamster SC is GABAergic interneurons. As many calretinin-IR cells are GABAergic interneurons in most other brain areas, this phenomenon in hamster SC is exceptional.

Development of the Formula for Natural Bread-making Starter (천연제빵 발효 Starter의 개발)

  • 이종열;이시경;조남지;박원종
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.32 no.8
    • /
    • pp.1245-1252
    • /
    • 2003
  • A starter formulation was developed to substitute a baker's yeast with natural starter when manufacturing bread products. To develop an active starlet, starter was formulated varying with types of wheat flours, level of water contents and various nutrients. Activities of starter were investigated in terms of viable counts of microbes and change of pH and total titratible acidity Domestic wheat flours contain 100 times more number of lactic acid bacteria than yeast regardless of types of wheat flours. The more protein contents in wheat flours, the more stable microbes in starter. This was considered to be the result of buffering effect of wheat proteins. The optimum level of protein content to ensure the activity of starter was more than 12.0%. Optimum level of water content in active starter was 110% based on strong flour. The more water or the less water had the tendency of decreasing viable counts of microbes. Addition of salt and sucrose had increased the activity of starters. However oligosaccharides did not affect the activity of starter. The optimum concentrations of salt and sucrose were 1.0% and 5.0% respectively. Bread with the starter was higher scored than breads with yeast in terms of all the quality and sensory characteristics except their volumes. In conclusion, a starter formulated with strong flour 100%, water 110%, salt 1% and sucrose 5% was considered to have high potential as a substitute of yeast in making natural bread.

Flexibility Study of Silicon Thin Film Transferred on Flexible Substrate (폴리머 기판 위에 전사된 실리콘 박막의 기계적 유연성 연구)

  • Lee, Mi-Kyoung;Lee, Eun-Kyung;Yang, Min;Chon, Min-Woo;Lee, Hyouk;Lim, Jae Sung;Choa, Sung-Hoon
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.20 no.3
    • /
    • pp.23-29
    • /
    • 2013
  • Development of flexible electronic devices has primarily focused on printing technology using organic materials. However, organic-based flexible electronics have several disadvantages, including low electrical performance and long-term reliability. Therefore, we fabricated nano- and micro-thick silicon film attached to the polymer substrate using transfer printing technology to investigate the feasibility of silicon-based flexible electronic devices with high performance and high flexibility. Flexibility of the fabricated samples was investigated using bending and stretching tests. The failure bending radius of the 200 nm-thick silicon film attached on a PI substrate was 4.5 mm, and the failure stretching strain was 1.8%. The failure bending radius of the micro-thick silicon film attached on a FPCB was 2 mm, and the failure strain was 3.5%, which showed superior flexibility compared with conventional silicon material. Improved flexibility was attributed to a buffering effect of the adhesive between the silicon film and the substrate. The superior flexibility of the thin silicon film demonstrates the possibility for flexible electronic devices with high performance.

Effects of Sulfur Dioxide on Pigments, Frotein Content and Photosystem II Activity of Barley and Corn Leaves (보리와 옥수수 잎의 색소, 단백질 함량 및 관계II 활성에 미치는 ${SO}^2$의 영향)

  • 정화숙
    • Journal of Plant Biology
    • /
    • v.25 no.3
    • /
    • pp.135-151
    • /
    • 1982
  • This investigation was carried out to clarify the changes of pigments and soluble protein, and photosystem II activity in the leaves of barley (${SO}_2$-sensitive) and corn (${SO}_2$-resistant) seedlings induced by the ${SO}_2$ fumigation (10, 50ppm). The pH changes of the leaf extract, the content of sulfite and sulfate, the activities of catalase, peroxidase, and polyphenoloxidase were compared in the leaves of barley and corn seedlings induced by ${SO}_2$ fumigation. The results are summarized as follows: An appreciable effect of pH change of leaf extract by ${SO}_2$ fumigation was observed in barley leaves (pH 6.10 to 5.18), but only a small change occurred in corn leaves (pH 5.66 to 5.50). The same pattern of pH changes was recorded when the solution of 0.2N HCl was added to leaf extract, providing lower buffering capacity of the barley leaves than corn leaves. After 2 hours of exposure to 10 ppm ${SO}_2$, the contents of ${SO}^{2-}_3$ and ${SO}^{2-}_4$ were increased in barley leaves, while only ${SO}^{2-}_4$ increased in corn leaves. After fumigation with 10ppm ${SO}_2$ for 2 hours, barley leaves showed significant decreases in activities of catalase, to 17% peroxidase, to 58%, and polyphenoloxidase, to 88%. Corn leaves showed increases in activities of peroxidase, to 136%, and polyphenoloxidase, to 128%. Absorption spectra of pigments obtained from ${SO}_2$-fumigated leaves were gradually decreased with the fumigation time increases, but the decrease was more significant in barley leaves. Fumigation with 50ppm ${SO}_2$ for 2 hours induced the greatest decomposition in carotenoid, followed by chlorophyll a and then chlorophyll b in barley leaves. The ratio of chlorophyll a/b was decreased from 4.1 to 3.6 in barley leaves, but in corn leaves it was maintained almost a constant level(4.9-4.8). The rate of decomposition of chlorophyll and carotenoid in corn leaves was very slow than those in the barley leaves. Fumigation with 50 ppm ${SO}_2$ for 2 hous, decreased the protein content of barley leaves to 59%, and that of corn leaves to 89%, and the extent of decrease in protein content was greater than that of pigments in barley and corn leaves. The rate of DCIP9dichlorophenol indophenol) photoreduction in ${SO}_2$-fumigated leaves was decreased to 18 and 67% in barley and corn leaves, respectively. However, DCIP photoreduction was considerably recovered about 32 and 92% with the addition of DPC(diphenylcarbazide) as an exogenous electron donor in barley and corn leaves, respectively.

  • PDF

A study on the Effects of Employees' Socio-emotional Problems on Stress, Depression, and Self-esteem (근로자의 사회정서적 문제가 스트레스와 우울 및 자아존중감에 미치는 영향 연구)

  • Choi, Soo-Chan;Park, Hae-Woong
    • Korean Journal of Social Welfare
    • /
    • v.57 no.4
    • /
    • pp.177-196
    • /
    • 2005
  • Today's employees are facing various socio-emotional problems due to the lack of appropriate supports and intervention in the workplace. These problems, however, cause considerable stress and inflict fatal damage on the quality of the employees' lives. Thus, this study analyzed the negative effects of the employees' socio-emotional problems on their stress, depression, and a sense of self-esteem. As a result, the study has identified that the problems occurred widely in the work life area such as job-related problem, predicament of retirement, workplace violence, family life area such as family relationship, child education, crisis problem, and lastly culture and health related area. This study also found that the socio-emotional problems in the three areas were the main stressors after all and they once again negatively affected depression and a sense of self-esteem. However, the role of social support, which is known to have the buffering effect on depression and a sense of self-esteem, was not sufficiently proved. This strongly implies that traditional social supports necessarily have limitations to overcome employees' socio-emotional problems in hand and thus systematic intervention toward the troubled workers in the organizational level must be required.

  • PDF

A STUDY ON THE ENAMEL EROSION CAUSED BY ORANGE JUICES (오렌지쥬스의 치아 법랑질 침식효과에 대한 연구)

  • Lee, Chang-Yun;Jung, Tae-Sung;Kim, Shin
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.31 no.4
    • /
    • pp.617-623
    • /
    • 2004
  • Acidic drink has been known as a cause of tooth erosion. The purpose of this study is to verify the acid levels of orange juices in market and evaluate the erosion effects on the enamel of deciduous teeth by orange juices in relatively short period of time. With four kinds of orange juice selected from market, pH, buffering capacity and concentration of Ca and P ion were measured. And forty segments of normal enamel of deciduous incisors were divided into four groups and level of erosion was measured by surface hardness test before and after soaking at 50ml of orange juice for 10 minutes. The results of this study showed that the average pH of orange juices was 4.0 and this pH value was so acidic as to cause the tooth erosion. There were differences in small quantity for each group of teeth, however, the result was statistically so significant that orange juices can cause enamel erosion in relatively short period of time.

  • PDF