• Title/Summary/Keyword: $^{13}C$

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/$^{13}C 및 ^{15}N$ 추적에 의한 탄소 및 질소 동화기전의 상관성에 관한 연구

  • ;T. Yoneyama
    • Proceedings of the Korean Society of Grassland Science Conference
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    • 1999.06a
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    • pp.82-83
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    • 1999
  • 탄소 및 질소동화의 상관성을 규명하기 위해 $^{13}$C(pulse chase)와 $^{15}$ N(continuous)을 labeling 한 후 6시간 동안 탄소 및 질소대사물로 동화된 동위원소를 분석하여 엽신, 엽병 및 뿌리조직 사이의 대사적 교감에 있어 탄소 및 질소 동화산물의 역할을 살펴보았다 $^{13}$$CO_2$로 75분간 labeling 한 후(0h), 광합성에 의해 고정된 $^{13}$C는 엽신에서 당의 형태로 주로 동화되었다.(중략)

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Algal Contribution to the Occurrence of Refractory Organic Matter in Lake Paldang, South Korea: Inferred from Dual Stable Isotope (13C and 15N) Tracer Experiment (팔당호 난분해성 유기물에 대한 조류기원 유기물의 기여)

  • Lee, Yeonjung;Ha, Sun-Yong;Hur, Jin;Shin, Kyung-Hoon
    • Korean Journal of Ecology and Environment
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    • v.52 no.3
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    • pp.192-201
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    • 2019
  • While a fairly large amount of organic matter is produced daily via phytoplankton photosynthesis in Lake Paldang, South Korea, knowledge of the role of algal-derived organic matter (OM) as a refractory OM source is not adequate. To understand the contribution of algal-derived OM to the refractory pool, biodegradation experiment and $KMnO_4$ oxidation experiment were conducted for 60 days using $^{13}C$ and $^{15}N$ labeled natural phytoplankton assemblage. The assemblage was collected from Lake Paldang on May 20, 2010. The photosynthetically produced total organic carbon ($TO^{13}C$), particulate organic carbon ($PO^{13}C$), and particulate nitrogen ($P^{15}N$) remained at 26%, 20%, and 17% of the initial concentrations, respectively, in the form of non-biodegradable organic matter. In addition, 12% and 38% of $PO^{13}C$ remained after $KMnO_4$ treatment on Day 0 and 60, respectively. These results indicate that photosynthetic products could be an important source of refractory organic matter after microbial degradation. Moreover, the microbially transformed algal-derived OM could contribute to the oxidation rate of the chemical oxygen demand.

Initiation and growth of fruitbody of oyster mushroom as affected by cultivation temperature (느타리버섯 생육온도와 자실체의 발생과 생장)

  • Jhune, Chang-Sung;Kong, Won-Sik;Yoo, Young-Bok;Jang, Kab-Yeul;Paik, Su-Bong;Chun, Se-Chul
    • Journal of Mushroom
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    • v.4 no.1
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    • pp.33-38
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    • 2006
  • Bottle cultivation was conducted to clarify varietal differences and physiological characteristics of oyster mushroom under different temperatures. Mushroom pinheading and yield in each temperature showed different results according to the strains. Specially, Weonhyeong3-ho could not sprout over $16.5^{\circ}C$, but after pinheading at $13^{\circ}C$, its fruitbody was able to grow normally at all tested temperatures. Sambok, a high temperature strain, sprouted at $10^{\circ}C$ and then withered up. Fruitbody of this strain obtained at $13^{\circ}C$ could not grow normally at $10^{\circ}C$ and $25^{\circ}C$ conditions. Colour of fruitbodies turned close to white at high temperature. On the other hand, at low temperature, strains with gray fruitbody changed close to black and those with brown fruitbody turned to dark brown. With regards to fruiting trait, pinheading aspects were good even at low temperature. Those were, however, uneven and sprouted in patches and resulted in low quality and productivity as the temperature increased. When black fruitbody at $13^{\circ}C$ were moved to $23^{\circ}C$ and then to $13^{\circ}C$ again, colour of fruitbody turned to white and then recovered to blackish gray. These results confirmed that the colour of fruitbody responds to cultivation temperature.

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The Non-Enzymatic Browning and Shelf-Life of Dried Shrimp during Storage under Fluctuating Temperature Conditions (건조 새우의 변온저장중 갈변 및 Shelf-life)

  • KIM Yong-Ju;KIM Mu-Nam;KANG Moon-Sun;CHO Young-Je;KIM Yuck-Yong;CHUN Soon Sil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.1
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    • pp.7-12
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    • 1994
  • The kinetics of browning reaction of dried shrimp powder samples were investigated during storage. The temperature conditions of the ding process were $25^{\circ}C\;and\;45^{\circ}C$, and the samples were stored at water activity ($a_w$) of 0.33, 0.44, 0.52, 0.65 and temperatures of $35^{\circ}C,\;45^{\circ}C,\;55^{\circ}C$ and temperature fluctuations between $33^{\circ}C\;and\;55^{\circ}C$. When the shrimp was dried at $25^{\circ}C$ the activation energies obtained from the Arrhenius plot ranged from 13.57 to 14.33 kcal/mol. From these energies of activation, the $Q_{10}$ values at $25^{\circ}C$ showed 1.93 to 2.00. In the case of drying at $45^{\circ}C$ the activation energies were $13.12{\sim}13.61\;kcal/mol$ and $Q_{10}$ values were $1.89{\sim}1.93$, respectively. In addition, a storage study under square-wave fluctuating temperature conditions was carried out by varying the shrimp sample temperature between $35^{\circ}C\;and\;55^{\circ}C$ within 7 days regular fluctuation cycle. The data obtained from the fluctuating temperature storage study will be used in the prediction of shelf-lives. The shelf-lives assessed at $25^{\circ}C$ from the accelerated shelf-life tests ranged from 4 days at aw 0.65 to 139 days at aw 0.33.

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Effect of Temperature on Development and Reproduction of the Persimmon Fruit Moth, Stathmopoda masinissa (Lepidoptera: Stathmopodidae) (감꼭지나방(나비목: 감꼭지나방과)의 발육과 생식에 미치는 온도의 영향)

  • 박은철;최경환;김정화;조수원;김길하
    • Korean journal of applied entomology
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    • v.40 no.4
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    • pp.297-300
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    • 2001
  • Development and reproduction of the persimmon fruit moth, Stathmopoda masinissa, were investigated under different temperatures (15, 20, 25, and 3$0^{\circ}C$). It took 96.1 days to grow from egg to adult at 2$0^{\circ}C$, 43.2 days at $25^{\circ}C$, and 34.6 days at 3$0^{\circ}C$. At 15$^{\circ}C$, all tested individuals died before pupation. The developmental threshold temperatures for egg, larva, pupa, and adult were 12.2, 13.5, 13.8, and 13.4$^{\circ}C$, respectively. The total effective temperatures for egg, larva, pupa, and egg to adult were 74.0, 331.3, 160.5, and 569.9 degree days, respectively. The hatching, pupation, and emergence rates were highest at $25^{\circ}C$. The average life span of adult prior to laying eggs and the total life span of adult were 12.6 and 29.3 days at 2$0^{\circ}C$, 3.8 and 8.6 days at $25^{\circ}C$, and 2.5 and 7.0 days at 3$0^{\circ}C$, respectively. Mean generation time in days (T) was shorter at higher temperature. Net reproductive rate per generation (R$_{o}$) was lowest at 2$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) was highest at $25^{\circ}C$ as 0.066.

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Effective Screening Condition for Low-Temperature Germinability of Rice (벼 저온발아성의 효율적 검정 조건)

  • Kang, Jong-Re;Lim, Sang-Jong;Kim, Soon-Chul;Ko, Mi-Suk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.6
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    • pp.711-715
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    • 1995
  • This study was carried out to determine the desirable screeing condition for low-temperature germinability of rice seeds. The germination test was performed with fifty rice varieties from three countries, mainly including the recent Korean rice cultivars. The analyzed result of germination test under three temperature conditions(13$^{\circ}C$, 16$^{\circ}C$, $25^{\circ}C$) pointed out that 11 days after seeding at 13$^{\circ}C$ was the most efficient testing condition for low-temperature germinability in terms of mean and variation in germination rate. Highly significant correlations were observed between germination rates of 11 days after seeding at 13$^{\circ}C$ and germination coefficients, average days of germination at 13 for 20 days. Low-temperature germinability were highly positively associated with days to heading or amylose content, but negatively correlated with grain width.

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Backbone 1H, 15N, and 13C Resonance Assignment and Secondary Structure Prediction of HP0495 from Helicobacter pylori

  • Seo, Min-Duk;Park, Sung-Jean;Kim, Hyun-Jung;Seok, Seung-Hyeon;Lee, Bong-Jin
    • BMB Reports
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    • v.40 no.5
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    • pp.839-843
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    • 2007
  • HP0495 (Swiss-Prot ID; Y495_HELPY) is an 86-residue hypothetical protein from Helicobacter pylori strain 26695. The function of HP0495 cannot be identified based on sequence homology, and HP0495 is included in a fairly unique sequence family. Here, we report the sequencespecific backbone resonance assignments of HP0495. About 97% of all the $^1HN$, $^{15}N$, $^{13}C{\alpha}$, $^{13}C{\beta}$, and $^{13}CO$ resonances were assigned unambiguously. We could predict the secondary structure of HP0495, by analyzing the deviation of the $^{13}C{\alpha}$ and $^{13}C{\beta}$ shemical shifts from their respective random coil values. Secondary structure prediction shows that HP0495 consists of two $\alpha$-helices and four $\beta$-strands. This study is a prerequisite for determining the solution structure of HP0495 and investigating the protein-protein interaction between HP0495 and other Helicobacter pylori proteins.

Backbone 1H, 15N, and 13C Resonance Assignment and Secondary Structure Prediction of HP1298 from Helicobacter pylori

  • Kim, Won-Je;Lim, Jong-Soo;Son, Woo-Sung;Ahn, Hee-Chul;Lee, Bong-Jin
    • Journal of the Korean Magnetic Resonance Society
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    • v.12 no.2
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    • pp.65-73
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    • 2008
  • HP1298 (Swiss-Prot ID ; P65108) is an 72-residue protein from Helicobacter pylori strain 26695. The function of HP1298 was identified as Translation initiation factor IF-l based on sequence homology, and HP1298 is included in IF-l family. Here, we report the sequence-specific backbone resonance assignments of HP1298. About 97% of all the $^{1}HN$, $^{15}N$, $^{13}C{\alpha}$, $^{13}C{\beta}$, and $^{13}CO$ resonances could be assigned unambiguously. We could predict the secondary structure of HP1298, by analyzing the deviation of the $^{13}C{\alpha}$ and $^{13}C{\beta}$ shemical shifts from their respective random coil values. Secondary structure prediction shows that HP1298 consists of six $\beta$-strands. This study is a prerequisite for determining the solution structure of HP1298 and investigating the structure-function relationship of HP1298. Assigned chemical shift can be used for the study on interaction between HP1298 and other Helicobacter pylori proteins.

Effects of $Cr_2O_3$ Addition in PSS-PZT Piezoelectric Ceramics for Surface Acoustic Wave Filter ($Cr_2O_3$가 탄성 표면파 필터용 PSS-PZT계 압전 세라믹스에 미치는 영향)

  • 홍재일;손은영;박창엽
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.5
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    • pp.502-507
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    • 1992
  • To improve temperature stability, 0.05Pb(SnS11/2TSbS11/2T)OS13T-0.35PbTiOS13T-0.60PbZrOS13T+0.4[wt%]MnO S12T piezoelectic ceramics were manufactured with the addition of CrS12TOS13T by Hot Press method. And the SAW delay line was fabricated and effects of CrS12TOS13T to the propagation characteristics of SAW was investigated, and the SAW filter was fabricated on C4 specimen added by 0.2[wt%] CrS12TOS13T whose propagation characteriatics of surface acoustic wave were the bast and its frequency characteristics was investigated. Electromechancal coupling factor(kS1sTS02T) was 3.11[%] and its temperature coefficient of the center frequency(CS1foT)was -21.27[ppm/$^{\circ}C$] in C4. The 31[MHz]]SAW IF filter of C4 scarcely had diffraction phenomena and therefore it was proper.

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Comparison of Volatile Aroma Components from Saussurea lappa C.B. Clarke Root Oils

  • Chang, Kyung-Mi;Kim, Gun-Hee
    • Preventive Nutrition and Food Science
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    • v.13 no.2
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    • pp.128-133
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    • 2008
  • The volatile flavor components were isolated from the roots of Saussurea lappa C.B. Clarke produced in Korea and China by the hydro distillation, and were analyzed by gas chromatography-mass spectrometry (GC/MS). 63 aroma compounds representing 87.47% of the total peak area were tentatively identified, including 13 alcohols (22.56%), 26 hydrocarbons (21.78%), 4 aldehydes (21.24%), 11 ketones (18.04%), 1 oxide (0.52%), 3 esters (0.16%), 1 carboxylic acid (0.02%) and 4 miscellaneous components (3.15%). 46 volatile flavor components of imported S. lappa C.B. Clarke constituted 65.69% of the total volatile composition were tentatively characterized, consisting of 1 aldehyde (23.32%), 24 hydrocarbons (16.69%), 10 ketones (15.84%), 7 alcohols (8.92%), 1 oxide (0.83%), 2 esters (0.07%) and 1 acid (0.02%). The predominant components of both essential oils were (7Z,10Z,13Z)-7,10,13-hexadecatrienal and dehydrocostuslactone.