• Title/Summary/Keyword: Disappearance Rate

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Kinetic Investigation of CO2 Reforming of CH4 over Ni Catalyst Deposited on Silicon Wafer Using Photoacoustic Spectroscopy

  • Yang, Jin-Hyuck;Kim, Ji-Woong;Cho, Young-Gil;Ju, Hong-Lyoul;Lee, Sung-Han;Choi, Joong-Gill
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1295-1300
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    • 2010
  • The $CO_2-CH_4$ reaction catalyzed by Ni/silicon wafers was kinetically studied by using a photoacoustic technique. The catalytic reaction was performed at various partial pressures of $CO_2$ and $CH_4$ (50 Torr total pressure of $CO_2/CH_4/N_2$) in the temperature range of 500 - $650^{\circ}C$ in a static reactor system. The photoacoustic signal that varied with the $CO_2$ concentration during the catalytic reaction was recorded as a function of time. Under the reaction conditions, the $CO_2$ photoacoustic measurements showed the as-prepared Ni thin film sample to be inactive for the reaction, while the $CO_2/CH_4$ reactions carried out in the presence of the sample pre-treated in $H_2$ at $600^{\circ}C$ were associated with significant time-dependent changes in the $CO_2$ photoacoustic signal. The rate of $CO_2$ disappearance was measured from the $CO_2$ photoacoustic signal data in the early reaction period of 50 - 150 sec to obtain precise kinetic data. The apparent activation energy for $CO_2$ consumption was determined to be 6.9 kcal/mol from the $CO_2$ disappearance rates. The partial reaction orders, determined from the $CO_2$ disappearance rates measured at various $PCO{_2}'S$ and $PCH{_4}'S$ at $600^{\circ}C$, were determined to be 0.33 for $CH_4$ and 0.63 for $CO_2$, respectively. Kinetic data obtained in these measurements were compared with previous works and were discussed to construct a catalytic reaction mechanism for the $CO_2-CH_4$ reaction over Ni/silicon wafer at low pressures.

THE INFLUENCE OF SELECTED CHEMICAL TREATMENTS ON THE RUMINAL DEGRADATION AND SUBSEQUENT INTESTINAL DIGESTION OF CEREAL STRAW

  • Wanapat, M.;Varvikko, T.;Vanhatalo, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.3 no.2
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    • pp.75-83
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    • 1990
  • An experiment was conducted with three ruminally and intestinally cannulated non-lactating cows of Finnish Ayrshire breed, to assess the ruminal degradation characteristics of oat (Avena sativa), rye (Secale cereale) and rice (Oryza sativa) straw by the nylon bag technique, and the subsequent post-ruminal degradation of their rumen-undegraded residues by using the mobile bag technique, respectively. The straw samples were untreated or treated with aqueous $NH_3$ or with urea solution in cold or hot water. The untreated straw samples were milled or chopped, and the treated straw samples were chopped. The constant values a, b, and c were computed according to the exponential equation, where a = intercept of degradation curve at time 0, b = potentially degradable material, c = rate of degradation of band (a+b) = maximum potential degradability (asymptote). It was found that nitrogen contents of chemically treated straw were markedly increased by both $NH_3$ and urea treatments. Milling the samples attributed to a remarkable loss at 0 h incubation time as compared to chopping of the respective samples. However, chemical treatment markedly improved the b value and the subsequent (a+b) values for dry matter, organic matter, neutral-detergent fiber, and acid-detergent fiber of the samples. Furthermore, temperature of the water used in the urea solutions was considered essential, since urea in hot water rather than in cold water seemed to enhance the overall degradability. The disappearance of rumen-incubated straw residues from the mobile bags ranged from 4.5 to 9.6% for the parameters measured. On average, the OM disappearance from bags was clearly higher for the residues of urea treated straw compared to those of ammonia treated straw, but the disappearance of NDF tended, however, to be higher on the ammonia treatment.

The Effect of Addition of Apple Pomace on Quality and In Situ Degradability of Orchardgrass Silage (사과박 첨가가 오차드그라스 사일리지의 품질과 In Situ 소실율에 미치는 영향)

  • 조익환;황보순;안종호;김현진;이주삼
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.21 no.3
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    • pp.137-144
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    • 2001
  • The quality including in situ degradability in the rumen of Holstein of the orchardgrass silage added with apple pomace was investigated in this study. The amount of apple pomace added in different treatments were 0, 20, 40 and 60% respectively. With higher amount of addition of apple pomace to orchardgrass, ADF, NDF and crude ash contents decreased significantly (p<0.05). Crude protein contents in the silages (11.8- 12.9%) were similar to that of 100% orchardgrass silage. Moisture contents increased according to the higher proportion of apple pomace in the silages. On the contrary to moisture content, pH was lower in 40-60% addition of apple pomace (3.7-3.9) than that of 100% orchardgrass silage (4.7). However the contents of lactic acid (1.7-2.5%), acetic acid (1.3- 1.7%) and total organic acid (2.9-4.2%) significantly increased according to higher levels of addition of apple pomace compared to the respective values of 100% orchardgrass silage (1.1%, 0.6% 1.7%). In siru disappearance rates of dry matter and NDF in the rumen were significantly higher at the stages of incubation after 24h in 40-60% addition of apple pomace than in 100% orchardgrass silage. No statistical differences were observed with quickly degradable fraction (a) and slowly degradable fraction (b) in the disappearance rates of dry matter and NDF. However, fractional rate of disappearance (c) and effective degradability (ED, k=0.08) for dry matter and NDF were significantly higher in 20-60% addition of apple pomace as 0.0076-0.0079 and 0.0099-0.0130. and 39.3-41.7% and 18.4- 20.6% respectively than the respective values of 0.0054 and 0.0064, and 36.8 and 16.5% of 100% orchardgrass silage. (Key words : Orchardgrass silage. Apple pomace. Lactic acid, In Situ Degradability. Effective degradability)

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IN SITU RUMINAL DEGRADATION KINETICS OF FORAGES AND FEED BYPRODUCTS IN MALE NILI-RAVI BUFFALO CALVES

  • Sarwar, M.;Mahmood, S.;Abbas, W.;Ali, C.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.5
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    • pp.533-538
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    • 1996
  • The rate and extent of digestion of dietary carbohydrates has a tremendous impact on ruminal fermentation and the productivity of the animals. The objective of the study was to determine the dry matter (DM) and neutral detergent fiber (NDF) degradabilities and rate and extent of feed byproducts (cotton seed cake, wheat bran), legumes [berseem (Egyptian clover), lucern (Medicago sativa), cowpeas (Vigna sinensis)], grasses [maize (Zea mays), millet (Panicum miliaceum), sorghum (Sorghum vulgare)] and wheat straw in ruminally fistulated male buffalo calves. By using nylon bags, 10 grams sample was exposed to the ruminal fermentation for 0, 1, 2, 4, 6, 10, 16, 24, 36, 48 and 96 hours. Dry matter and NDF degradability was measured at 48 hours. Extent of DM and NDF disappearance was determined at each time point. Rates of disappearance of DM and NDF were determined by regressing the natural logarithm of the percentage of original DM and NDF remaining in the bags between 1 and 96 hours. The dry matter digestibility (DMD) of the feed byproducts (FBP) and legume forages when incubated in the rumen of male buffalo calves were greater (p < 0.05) than grasses. Extent of digestion followed similar pattern as DMD. Rate of DMD was higher in FBP than in legumes and was the lowest in the wheat straw. The NDF degradability (NDFD) of FBP, legumes and grasses did not differ, however, wheat straw had the lowest NDFD from all the feeds tested. The lowest NDFD of wheat straw may have been due to the depressing effect of lignin on fiber digestion. The FBP and legumes had higher (p < 0.05) rates and lower extents of NDF digestion than grasses.

Effects of Protein and Carbohydrate Supplementations on Fibre Digestion and Microbial Population of Sheep

  • Jetana, T.;Abdullah, N.;Halim, R.A.;Jalaludin, S.;Ho, Y.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.5
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    • pp.510-521
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    • 1998
  • The effects of two types of protein, soybean meal (SBM) and fish meal (FM); and two types of energy supplements, corn flour (CF) and paper pulp (PP), on intake of guinea grass (Panicum maximum), fibre digestion and microbial activities in four Merino rams with an average weight of $54.4{\pm}4.5kg$ were studied. Each animal was fitted with a ruminal cannula and a duodenal cannula at the proximal position. The animals were fed twice daily with chopped guinea grass (5 cm) ad libitum and one of the four dietary supplements: 170 g FM+268 g PP; 170 g FM+268 g CF; 200 g SBM+200 g PP or 200 g SBM+200 g CF. All the supplements were mixed with 100 g molasses. In sacco and in vivo digestibilities, digesta flow rates, fermentation and microbial population were studied in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of dietary treatments. The effects of energy or protein sources were not significant on grass intake of sheep. The potential degradabilities of NDF and ADF were not significantly affected by any of the supplements. However, the energy and protein sources had significant efects on disappearance rate of NDF and ADF. The disappearance rate of both NDF and ADF were significantly (p < 0.05) higher in animals fed PP when compared to animals fed CF. Animals fed FM also showed significantly (p < 0.03) higher disappearance rate of ADF than those fed SBM. Animals fed PP showed better digestion in the rumen and total tract. Total flow of NDF and ADF through the duodenum was not significantly affected by the various supplements. The mean rumen pH values (5.8-6.1) were not significantly different among the four different diets. The concentration of rumen ammonia was significantly (p < 0.0001) higher in animals fed SBM (235-266.4 mg N/L) supplement than in animals fed FM (174.9-179.7 mg N/L), while total VFA concentration was not significantly affected by both energy and protein supplements. Mean values of total VFA ranged from 72.5-82.3 mM. Molar proportions of acetate, propionate and butyrate were typical of a roughage type fermentation. Molar proportion of acetate was significantly (p < 0.0001) higher in sheep fed PP when compared to sheep fed CF. Animals fed FM had higher total viable bacterial counts, while animals fed CF showed higher protozoal numbers. Proportions of cellulolytic bacteria were only slightly higher in animals fed SBM or PP.

Studies on the Pharmacodynamic Action of Methemoglobin (Methemoglobind의 약력학적(藥力學的) 작용(作用)에 관(關)한 연구(硏究))

  • Kim, Kwang-Yun
    • The Korean Journal of Pharmacology
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    • v.2 no.1 s.2
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    • pp.49-69
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    • 1966
  • For the purpose of stydying the pharmacodynamic action of methemoglobin, the author made the following experiments: 1. Preparation of hemoglobin and methemoglobin solutions: Red cell suspension from rabbit blood was hemolysed with distilled water and then divided into two portions. One portion was dialysed through cellophane paper and made isotonic with the proper amount of sodium chloride. The second portion was treated with sodium nitrite to convert hemoglobin to methemoglobin, dialysed through cellophane paper and made isotonic. 2. The concentration of methemoglobin in solution, plasma and urine was determined by Horecker and Brackette's method, and that of hemoglobin by the cyanmethemoglobin method. 3. The concentration of methemoglobin and hemoglobin in the plasma and urine of rabbits was measured at several intervals of time after infusion of the above samples. 4. The blood pressure and respiration of rabbits were recorded on a kymograph, and the effects of the samples on them were observed. 5. The effects of the samples on the movements of the in-situ heart and the isolated intestine of rabbits were studied. 6. The kidneys of rabbits were excised 4 to 5 hours after injection of the samples, and histopathological examinations were made. These experiments revealed the following results: 1. When methemoglobin solution was allowed to stand in room air, there was no decrease in the concentration of methemoglobin. 2. When methemoglobin solution was mixed with whole blood and incubated at $37^{\circ}C$, the concentration of methemoglobin decteased gradually. 3. After the infusion of methemoglobin and hemoglobin solutions, the rate of disappearance of methemoglobin in the plasma was more rapid than that of hemoglobin in the plasma. The higher the initial concentration in the plasma, the larger was the rate of disappearance of methemoglobin. 4. The rate of disappearance of methemoglobin was exceedingly rapid for 30 minutes after the infusion. 5. The urinary excretion of methemoglobin was more rapid than that of hemoglobin. 6. It would seem that the circulating blood contains substances which are promptly mobilized in the plasma to reduce methemoglobin to hemoglobin. 7. Moderate amounts of methemoglobin solution caused some rise in the blood pressure and a transient acceleration of the respiration of the rabbits. These effects of methemoglobin were milder than those of hemoglobin. 8. The movements of the in-situ heart and the isolated intestine of rabbits were accelerated by methemoglobin. These accelerating effects were milder than those of hemoglobin. 9. In the kidneys of rabbits treated with methemoglobin solution, hyperemia of the glomeruli, cloudy swelling and hemoglobin deposit in the tubular epithelium, hemoglobin casts in the tubular lumina of the proximal tubules, and interstitial congestion were constantly observed. There was no definite difference between the histological findings in the rabbit kidneys injected with methemoglobin, and those injected with hemoglobin solutions.

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EFFECT OF DIETARY PANAX GINSENGS ON THE RATE OF THE BLOOD ETHANOL CLEARANCE (식이성(食餌性) 인삼(人蔘)이 백서혈액(白鼠血液) ethanol의 청소율(淸掃率)에 관(關)한 효과(效果))

  • Chang, Ie-Soo
    • The Journal of Internal Korean Medicine
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    • v.1 no.1
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    • pp.92-97
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    • 1976
  • Upon feeding dried Ginseng to rats of either low-protein or high protein diet ethanol was administered intraperitoneally and disappearance rate blood alcohol was enzymatically measure. In terms of residual blood alcohol after a time lapse of 3.5 hours between intraperitonial administration and blood withdrawal neither ginseng nor ginseng plus 40% casein did improve the rate, of alcohol clearance but sexual difference was clearly demonstrated in favor of female rats. In the case of blood withdrawn only 2 hours after intraperitoneal injection of alcohol, the tendency of female superiority in alcohol clearance rate is demonstrated when a comparison is made among the groups fed with ginseng and this was particularly true is groups of rats fed with basal diet plus 1 percent ginseng residual blood ethanol being 15.4 mg/ml vs. 8.8 mg/ml. Liver homogenate alcohol dehydrogenase activity measured in terms of residual ethanol content after in vitro reaction on which a known amount of alcohol was added clearly demonstrated a male superiority in alcohol clearance.

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Study on Renal Anemia - A Double Tracer Study on Iron Metabolism and Red Cell Life Span in Chronic Renal Diseases using Radioactive Iron ($^{59}Fe$) and Chromium($^{51}Cr$) - (신성빈혈(腎性貧血)에 관(關)한 연구(硏究) - 만성신질환(慢性腎疾患)의 철대사(鐵代謝) 및 적혈구수명(赤血球壽命)에 관(關)하여 -)

  • Jung, Kyung-Tae;Lee, Mun-Ho
    • The Korean Journal of Nuclear Medicine
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    • v.2 no.1
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    • pp.27-41
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    • 1968
  • The ferrokinetics and red cell life spans of the patients with chronic glomerulonephritis were investigated by the double tracing method using radioactive iron ($^{59}Fe$) and chromium ($^{51}Cr$). According to the serum NPN levels, the patients were subdivided into 3 groups: Group 1. 6 patients, had the levels below 40 mg/dl Group 2. 6 patients, had the levels between 41 mg/dl to 80 mg/dl Group 3. 10 patients, had the levels above 80 mg/dl The results were as follows: 1) Red blood cell-, hematocrit- and hemoglobin values were moderately reduced in patients with normal serum NPN levels, while markedly reduced in patients with elevated serum NPN levels. 2) The plasma volume was increased, while the red cell volume was decreased in patients with elevated serum NPN levels, hence, total blood volume was unchanged. 3) The serum iron level was slightly reduced h patients of groups 1 and 2, while was within the normal ranges in patients of group 3. 4) i) In patients with normal serum NPN levels, the plasma iron disappearance rate, red cell iron utilization rate, red cell iron turnover rate, daily red cell iron renewal rate, circulating red cell iron and red cell iron concentration were within the normal ranges, while the plasma iron turnover rate was slightly reduced. ii) In patients with elevated serum NPN levels, the plasma iron disappearance rate was delayed, while the plasma iron turnover rate was within the normal ranges. The red cell iron utilization rate, red cell iron turnover rate and circulating red cell iron were decreased and the period in which the red cell iron utilization rate reachd its peak was delayed in Group 3 patients. The daily red cell iron renewal rate and the red cell iron concentration were unchanged. iii) The mean red cell life span was within the normal ranges in patients with normal serum NPN levels, while was shortened in patients with elevated serum NPN levels.

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Design and Implementation of Accident Prevention System for Second-Class Citizen based on Bluetooth and NFC (블루투스 및 NFC 기반 사회약자 사고방지 시스템 설계 및 구현)

  • Lee, Ki-Young;Lee, Myeong-Gu;Lim, Myung-Jae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.6
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    • pp.131-136
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    • 2013
  • The rate of disappearance people such as children, demented elderly, and disabled is being increased every year. In this paper, we suggest accident prevention system for second class citizens which is based on Bluetooth and NFC to prevent second class citizens' disappearance. Nowadays, most of people are using a smart phone, and these smart phones usually have Bluetooth and NFC module. Therefore in this paper, we would design and implement the accident prevention system for second class citizens and their guardians by using smart phones which have Bluetooth and NFC module.

An Analysis of Fishing Village Extinction Factors to Increase the Inflow of Fishing Village Population (어촌인구 유입 증대를 위한 어촌소멸 요인 분석)

  • Kyeong-Won Woo
    • The Journal of Fisheries Business Administration
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    • v.54 no.1
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    • pp.023-036
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    • 2023
  • Global food prices have skyrocketed due to international uncertainties such as COVID-19 and the Russian-Ukrainian War. In this context, the importance of rural areas as a source of food production is also rapidly increasing. However, the issue of regional extinction is emerging as Korea faces the world's lowest fertility rate and fastest aging population. Also, rural areas are losing their population more rapidly than large cities. Therefore, this study aims to analyze the factors that can encourage the influx of fishermen to prevent the disappearance of these fishing villages. As a result of the analysis, in order to prevent the disappearance of fishing villages, among the infrastructure, natural environment, and residential environment variables, the ratio of aged housing related to quality of life, culture and amenities coefficients were found to have a greater impact than other variables. Based on these results, it is judged that it is necessary to establish a sufficient level of infrastructure in fishing villages and to prioritize policies for improving the residential environment.