• Title/Summary/Keyword: $\delta^{13}C$

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Nutrient Requirements of Exercising Swamp Buffalo, Bubalus bubalis, from Materials Balance and In Vivo Body Composition by the Body Density Method. I. Aspects of Energy and Protein Metabolism in Working Cows

  • Mahardika, IG.;Sastradipradja, D.;Sutardi, T.;Sumadi, IK.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.5
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    • pp.605-612
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    • 2000
  • Four young swamp buffalo cows of similar age ranging in weight between 280 to 380 kg and trained to do physical work were used in a study to determine energy and protein requirements for draught using a $4{\times}4$ Latin square designed experiment. The experiment consisted of field trials employing 4 levels of work load, e.g. no work as control, and loads amounting 450 to 500 Newton (N) pulled continuously for 1, 2 and 3 h daily for 14 consecutive days. Cows were fed king grass (Penisetum purpuroides) ad libitum and were subjected to materials balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus retained energy (RE). The results show that EE while not working ($EE_{resting}$) was $0.42kgW^{0.75}MJ/d$ and maintenance ME ($ME_m$) was $0.37kgW^{0.75}MJ/d$. ME requirement increased to 1.65 times maintenance for the work of 3 hours. The energy expended for doing exercise ($E_{exercise}$) was 9.56, 20.0 and 25.86 MJ/cow for treatments 1, 2 and 3 II, respectively. Fat retention was absent in all groups of working cows, but protein retention was only negative for cows undertaking 3 h work. The relationship between $E_{exercise}$ (MJ), work load (F, kN), work duration (t, h) and body mass (W, kg) was found to be: $E_{exercise}=(0.003F^{1.43}t^{0.93})/W^{0.09}MJ$. The maintenance requirement for digestible protein was $2.51kgW^{0.75}g/d$, whereas digestible protein for growth ($DP_{growth}$) and for work ($DP_{work}$) followed the equations: $DP_{growth}=[(258+1.25W^{0.75}){\Delta}Wkg/d]g$ and $DP_{work}=[12.59e^{0.95t}]g$, respectively The coefficients a, b and c for the calculation of $E_{exercise}$ components according to the Lawrence equation were found to be 2.56 J/kgW.m, 5.2 J/kg load carried.m and 0.29, respectively, thus efficiencies to convert ME into work were 0, 16.09, 27.3 and 32.44% for control, 1, 2 and 3 h/d work, respectively. ME and DP requirements for a 250 to 400 kg working buffalo cow allowing to growth up to 0.5 kg/d are presented.

Holocene Environments of the Buyeo Area Choongnam Province: Reconstructed from Carbon Isotopic and Magnetic Evidences from Alluvial Sequences (충남 부여지역의 홀로세 기후변화 -탄소동위원소분석과 대자율분석을 이용하여-)

  • Park, Kyeong;Park, Ji-Hoon
    • Journal of the Korean Geographical Society
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    • v.46 no.4
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    • pp.396-412
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    • 2011
  • Multi-proxy analysis was used to produce a high-resolution paleoclimatic record from a thick section of the Holocene alluvial fan deposit in Gatap-ri, Buyeo. According to ${\delta}^{13}C$ analyses, five minor climate fluctuations can be determined. From the stage I to stage VI, climate changes are as follows: cool-dry, warm-humid, cool-dry, warm humid, drier than stage IV, and finally more humid environment than stage V. According to magnetic susceptibility records, four different stages can be identified, among which stage ii shows the highest susceptibility. Stage-i deposit is derived from sediments of back marsh-type wetland. Stage-ii and stage-iii deposits, however, show higher magnetic susceptibility because magnetite-enriched soil from weathered upland was transported to the area to form an alluvial fan deposits. Stage-iv deposit is comparable to the modern plow horizon.

Copolymerization of Ethylene and Norbornene via Polymethylene Bridged Dinuclear Constrained Geometry Catalysts

  • Zhu, Yin-Bang;Jeong, Eung-Yeong;Lee, Bae-Wook;Kim, Bong-Shik;Noh, Seok-Kyun;Lyoo, Won-Seok;Lee, Dong-Ho;Kim, Yong-Man
    • Macromolecular Research
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    • v.15 no.5
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    • pp.430-436
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    • 2007
  • The dinuclear half-sandwich CGCs (constrained geometry catalyst) with a polymethylene bridge, $[Ti({\eta}^5 : {\eta}^1-indenyl)SiMe_2NCMe_3]_2(CH_2)_n]$[n = 6 (1) and 12 (2)], have been employed in the copolymerization of ethylene and norbornene (NBE). To compare the mononuclear metallocene catalysts; $Ti({\eta}^5 : {\eta}^1-2-hexylindenyl)SiMe_2NCMe_3$ (3), $(Cp^* SiMe_2NCMe_3)$Ti (Dow CGC) (4) and ansa-$Et(Ind)_2ZrCI_2$ (5), were also studied for the copolymerization of ethylene and NBE. It was found that the activity increased in the order: 1 < 2 < 3 < 5 < 4, indicating that the presence of the bridge between two the CGC units contributed to depressing the polymerization activity of the CGCs. This result strongly suggests that the implication of steric disturbance due to the presence of the bridge may playa significant role in slowing the activity. Dinuclear CGCs have been found to be very efficient for the incorporation of NBE onto the polyethylene backbone. The NBE contents in the copolymers formed ranged from 10 to 42%, depending on the polymerization conditions. Strong chemical shifts were observed at ${\delta}$42.0 and 47.8 of the isotactic alternating NBE sequences, NENEN, in the copolymers with high NBE contents. In addition, a resonance at 47.1 ppm for the sequences of the isolated NBE, EENEE, was observed in the $^{13}C-NMR$ spectra of the copolymers with low NBE contents. The absence of signals for isotactic dyad at 48.1 and 49.1 ppm illustrated there were no isotactic or microblock (NBE-NBE) sequences in the copolymers. This result indicated that the dinuclear CGCs were effective for making randomly distributed ethylene-NBE copolymers.

Recent Technological Advances in Optical Instruments and Future Applications for in Situ Stable Isotope Analysis of CH4 in the Surface Ocean and Marine Atmosphere (표층해수 내 용존 메탄 탄소동위원소 실시간 측정을 위한 광학기기의 개발 및 활용 전망)

  • PARK, MI-KYUNG;PARK, SUNYOUNG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.1
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    • pp.32-48
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    • 2018
  • The mechanisms of $CH_4$ uptake into and release from the ocean are not well understood due mainly to complexity of the biogeochemical cycle and to lack of regional-scale and/or process-scale observations in the marine boundary layers. Without complete understanding of oceanic mechanisms to control the carbon balance and cycles on a various spatial and temporal scales, however, it is difficult to predict future perturbation of oceanic carbon levels and its influence on the global and regional climates. High frequency, high precision continuous measurements for carbon isotopic compositions from dissolved $CH_4$ in the surface ocean and marine atmosphere can provide additional information about the flux pathways and production/consumption processes occurring in the boundary of two large reservoirs. This paper introduces recent advances on optical instruments for real time $CH_4$ isotope analysis to diagnose potential applications for in situ, continuous measurements of carbon isotopic composition of dissolved $CH_4$. Commercially available, three laser absorption spectrometers - quantum cascade laser spectroscopy (QCLAS), off-axis integrated cavity output spectrometer (OA-ICOS), and cavity ring-down spectrometer (CRDS) are discussed in comparison with the conventional isotope ratio mass spectrometry (IRMS). Details of functioning and performance of a CRDS isotope instrument for atmospheric ${\delta}^{13}C-CH_4$ are also given, showing its capability to detect localized methane emission sources.

A Study on Resisitance Performance of the Straight-Framed V-Bottom Hull Forms with High Displacement-Length Ratio (고(高) 배수량일장(排水量一長) 비(比) V-형(型) 직선늑골선형(直線肋骨船型)의 추진저항성능(推進抵抗性能)에 관(關)하여)

  • Kyu-Jong,Cho
    • Bulletin of the Society of Naval Architects of Korea
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    • v.6 no.1
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    • pp.25-34
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    • 1969
  • From viewpoints of over-all ship economy the straight framed V-bottom hull forms with chines are considered to be attractive even for usual commercial vessels, because increments of resistance over that of round hull forms, if any, can be well compensated with reduction in construction cost.[1] To investigate the influences of both prismatic coefficient and chine elevation on resistance performance, three models of straight-framed V-bottom hull forms which are similar to Prof. C. Ridgely-Nevitt's W-18, W-8, and W-20[2],[3] in size and hull form coefficients were tested at the SNU Ship Model Towing Tank for resistance measurements. They are of Cp=0.60, 0.65 and 0.70 and of ${\Delta}/(0.01L)^3=300$. Influence of variation of chine elevation on resistance performance were observed with the test results obtained at normal condition, and at the trimed by the stern by 2% and 4% of $L_{bp}$ at normal condition under same displacement. The hull form characteristics are shown in Table 1, and in Fig. 1, 2, 3, 4 and 5. The test results are shown in Fig 8, 9 and 10 in the form of Cr vs. $V/\sqrt{L}$ curves taking Cp as a parameter for normal condition, trim by the stern in 2% and 4% $L_{bp}$ at normal condition , respectively. Cr vs. $V/\sqrt{L}$ curves taking trim condition as a parameter are also shown in Fig 11, 12 and 13 for Cp=0.60 and 0.70, respectively. The best and the worst trim condition at given $V/\sqrt{L}$ in viewpoint of Cr are plotted for each Cp-value as shown in Fig 14, 15 and 16. From the above results the following conclusions are derived: (1) In general, the resistance performance of the straight-framed V-bottom hull forms are not inferior to those of round hull forms. At a certain range of $V/\sqrt{L}$ the former gives less resistance than the latter. (2) Regarding influences of Cp on Cr, it is observed that, at $V/\sqrt{L}$ less than about 0.925, the greater Cp-value gives the more increment of Cr, and that, at $V/\sqrt{L}$ greater than about 0.925 the smaller Cp-value gives the more increment of Cr. It is also noteworthy that the model of Cp=0.70 has remarkable hump on Cr vs. $V/\sqrt{L}$ curve between $V/\sqrt{L}=0.80$ and 0.90. (3) For higher speed within the test range, the chine elevation having the steeper slope around bow and the easier slope around amidship and stern, refered to watering, give the better results in resistance performance. (4) Assuming the chine elevations adopted for the tested models were not of the best, we would expect further improvement of resistance performance for such form. Hence, a systematic study on chine elevation is very disirable to prepare design data of general purpose for the such hull forms.

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Estimation of Pollutant Sources in Dangjin Coal-Fired Power Plant Using Carbon Isotopes (탄소 안정동위원소를 이용한 석탄화력발전소 인근 오염원 기원 추정 : 당진시를 중심으로)

  • Yoon, Soohyang;Cho, Bong-Yeon
    • The Journal of the Korea Contents Association
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    • v.21 no.3
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    • pp.567-575
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    • 2021
  • Residents in Dangjin, South Chungcheong Province, in which large-scale emissions facilities such as coal-fired power plants and steel mills are concentrated, are very much concerned about their health despite the local government's aggressive efforts to improve air quality and reduce greenhouse gases. To understand the impact of coal-fired power plants and external factors on local air pollution, the origins of local pollutants were investigated using stable carbon isotopes that are generally used as tracers of the provenance of fine or ultrafine dust. The origins of the pollutants were analyzed with the data library, built using the seasonally measured data for the two separate locations selected considering the distance from the coal-fired power plant and the analysis of previous studies, and with the back trajectory analysis. As a result of analyzing stable isotope ratios, the tendency of high concentration was found in the order of winter > spring > fall > summer. According to the data matching with the library, the mobile pollutants and open-air incineration had a relatively higher impact on the local air pollution. It is believed that this study, as a pilot study, should focus on securing the reliability of the study results through continuous monitoring and data accumulation.

Influence of Helicobacter pylori Infection on Gastric Motility in Children and Adolescents with Functional Dyspepsia (기능성 소화불량 소아청소년에서 위 운동에 대한 Helicobater pylori 감염의 영향)

  • Ryoo, Eell;Nam, Yoo-Nee;Kweon, Chang-Kyu;Kang, Sung-Kil;Cho, Kang-Ho;Son, Dong-Woo;Tcha, Hann
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.2
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    • pp.133-139
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    • 2009
  • Purpose: In spite of many reports about Helicobacter pylori infection in children with functional gastrointestinal disorders, there are few reports about the influence of H. pylori infection to functional dyspepsia and gastric motility. Therefore, we studied the influence of H. pylori infection on gastric myoelectrical activity in children with functional dyspepsia. Methods: Between August 2006 and December 2008 upper gastrointestinal endoscopies with biopsies, the rapid urease test and/or $^{13}C$ urea breath test, and electrogastrography (EGG) were performed on 63 patients with histologic chronic gastritis; patients with chronic disorders were excluded. Comparisons about gastric myoelectrical activities were made between H. pylori-positive children (n=25) and H. pylorinegative children (n=38). Results: The percentage of pre- and post-prandial normogastria was relatively lower in H. pylori-positive children than H. pylori-negative children (80% vs. 65%, and 80% vs. 68%, respectively). Compared to H. pylori-negative children, H. pylori-positive children had lower postprandial predominant power (8.18${\pm}$22.36 dB and 32.20${\pm}$24.18 dB, respectively; p<0.01) and a lower power ratio (${\delta}P$; -1.28${\pm}$6.18 vs. +4.62${\pm}$5.93, respectively; p<0.01). Conclusion: It was suggested that the gastric myoelectrical activity in children with chronic gastritis can be influenced by H. pylori infection. Thus, this study indicates that H. pylori infection may be predictable in children with functional dyspepsia through analyzing the EGG parameters, and treatment may be considered in H. pylori-positive children with impaired gastric activity, especially in the lower prevalence area.

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Hydrogeochemical and Environmental Isotope Study of Groundwaters in the Pungki Area (풍기 지역 지하수의 수리지구화학 및 환경동위원소 특성 연구)

  • 윤성택;채기탁;고용권;김상렬;최병영;이병호;김성용
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.4
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    • pp.177-191
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    • 1998
  • For various kinds of waters including surface water, shallow groundwater (<70 m deep) and deep groundwater (500∼810 m deep) from the Pungki area, an integrated study based on hydrochemical, multivariate statistical, thermodynamic, environmental isotopic (tritium, oxygen-hydrogen, carbon and sulfur), and mass-balance approaches was attempted to elucidate the hydrogeochemical and hydrologic characteristics of the groundwater system in the gneiss area. Shallow groundwaters are typified as the 'Ca-HCO$_3$'type with higher concentrations of Ca, Mg, SO$_4$and NO$_3$, whereas deep groundwaters are the 'Na-HCO$_3$'type with elevated concentrations of Na, Ba, Li, H$_2$S, F and Cl and are supersaturated with respect to calcite. The waters in the area are largely classified into two groups: 1) surface waters and most of shallow groundwaters, and 2) deep groundwaters and one sample of shallow groundwater. Seasonal compositional variations are recognized for the former. Multivariate statistical analysis indicates that three factors may explain about 86% of the compositional variations observed in deep groundwaters. These are: 1) plagioclase dissolution and calcite precipitation, 2) sulfate reduction, and 3) acid hydrolysis of hydroxyl-bearing minerals(mainly mica). By combining with results of thermodynamic calculation, four appropriate models of water/ rock interaction, each showing the dissolution of plagioclase, kaolinite and micas and the precipitation of calcite, illite, laumontite, chlorite and smectite, are proposed by mass balance modelling in order to explain the water quality of deep groundwaters. Oxygen-hydrogen isotope data indicate that deep groundwaters were originated from a local meteoric water recharged from distant, topograpically high mountainous region and underwent larger degrees of water/rock interaction during the regional deep circulation, whereas the shallow groundwaters were recharged from nearby, topograpically low region. Tritium data show that the recharge time was the pre-thermonuclear age for deep groundwaters (<0.2 TU) but the post-thermonuclear age for shallow groundwaters (5.66∼7.79 TU). The $\delta$$\^$34/S values of dissolved sulfate indicate that high amounts of dissolved H$_2$S (up to 3.9 mg/1), a characteristic of deep groundwaters in this area, might be derived from the reduction of sulfate. The $\delta$$\^$13/C values of dissolved carbonates are controlled by not only the dissolution of carbonate minerals by dissolved soil CO$_2$(for shallow groundwaters) but also the reprecipitation of calcite (for deep groundwaters). An integrated model of the origin, flow and chemical evolution for the groundwaters in this area is proposed in this study.

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Comparison of Rice Growth under Subtropical and Temperate Environments (아열대와 온대 기후 하에서 벼 생육 비교)

  • Park H.K.;Xu Migging;Lee K.B.;Choil W.Y.;Choil M.G.;Kim S.S.;Kim C.K.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.2
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    • pp.45-53
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    • 2006
  • The objectives of this study are to determine the primary yield components responsible for yield differences in a subtropical environment of the Hunan province China and in a temperature environment of Honam province Korea. Field experiments were conducted in a subtropical environment in Hunan province China during 2002 and in a temperate environment in Honam province Korea during 2003. Seven rice cultivars were grown under optimum crop management in each experiment field. Yield, yield components and plant dry matter were determined at maturation. The highest yield (567 kg/10a) was produced at Honam province by Jinyou 207, a Chinese cultivar, The maximum yield at Hunan province was 453 kg/10a by Sanyou 63. On the average across cultivars, Honam produced 23% greater yields than Hunan. Sink size (spikelets per $m^2$) was responsible far these yield differences. Panicle number per $m^2$ was much greater at Honam.

Effect of Defatted Soy flour on the Bread Making Properties of Wheat flour (탈지 대두분 첨가가 제빵 특성에 미치는 영향)

  • Yoo Yang-Ja;Chang Hak-Gil;Choi Young-Sim
    • Korean journal of food and cookery science
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    • v.21 no.3 s.87
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    • pp.301-310
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    • 2005
  • The effects of defatted soy flour on the physicochemical characteristics of dough and bread making properties were studied. Defatted soy flour is added to wheat flour for bread-making in order to maximize the use of isoflavones in the soybean. Different particle sizes of both defatted soy flour and wheat flour were prepared by grinding and sievingwith meshes. In the mixograph test, the addition of defatted soy flour to wheat flour increased the requirement for water and decreased the dough development time. Water absorption rates were also investigated to determine the optimum quantity of water for good dough. As the level of defatted soy flour mixed with wheat flour increased, the sedimentation and P.K. values decreased. In comparison with control, the bread made with defatted soy flour especially had a lower specific loaf volume. Specific loaf volume of wheat flour-defatted soy flour bread prepared (Ed- this is an incomplete sentence, it's only a subject clause, and I don't how what you intend to state). In terms of the staling rate and hardness of the wheat flour-defatted soy flour bread, the increased defatted soy flour had a faster staling rate during storage at 5? than at 25? for 5days. From the result of sensory evaluation, wheat flour-defatted soy flour breads containing up to $4\%$ defatted soy flour were rated as being of high quality.