• Title/Summary/Keyword: Low C/N Ratio

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INVESTIGATIONS OF OXIDATIONS OF SnOx AND ITS CHANGES OF THE PROPERTIES PREPARED BDEPOSITIONY REACTIVE ION-ASSISTED

  • Cho, J.S.;Choi, W.K.;Kim, Y.T.;Jung, H.J.;Koh, S.K.
    • Journal of Surface Science and Engineering
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    • v.29 no.6
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    • pp.766-772
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    • 1996
  • Undoped $SnO_x$ thin films were deposited on Si(100) substrate by using reactive ioassisted deposition technique (R-IAD). In order to investigate the effect of initial oxygen content and heat treatment on the oxidation state and crystalline structure of tin oxide films, $SnO_x$ thin films were post-annealed at 400~$600^{\circ}C$ for 1 hr. in a vacuum ~$5 \times 10^{-3}$ -3/ Torr or were directly deposited on the substrate of $400^{\circ}C$ and the relative arrival ration ($Gamma$) of oxygen ion to Sn metal varied from 0.025 to 0.1, i.e., average impinging energy ($E_a$) form 25 to 100 eV/atom. As $E_a$ increased, the composition ratio of $N_ON{sn}$ changed from 1.25 to 1.93 in post-annealing, treatment and 1.21 to 1.87 in in-situ substrate heating. In case of post-annealing, the oxidation from SnO to $SnO_2$ was closely related to initial oxygen contents and post-annealing temperature, and the perfect oxidation of $SnO_2$ in the film was obtained at higher than $E_a$=75 eV/atom and $600^{\circ}C$. The temperature for perfect oxidation of $SnO_2$ was reduced as low as $400^{\circ}C$ through in-situ substrate heating. The variation of the chemical state of $SnO_x$ thin films with changing $E_a$'s and heating method were also observed by Auger electron spectroscopy.

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Piezoelectric Properties of $Pb(Ni_{1/3}Nb_{2/3})O_{3}-PbZrO_{3}-PbTiO_{3}$ Ceramics doped with$Y_{2}O_{3}$ and Their Application to Multilayer Piezoelectric Actuators ($Y_{2}O_{3}$가 첨가된 $Pb(Ni_{1/3}Nb_{2/3})O_{3}-PbZrO_{3}-PbTiO_{3}$ 세라믹의 압전특성 및 적층형 압전 Actuator에 관한 연구)

  • Choi, Hae-Yun;Kwon, Jeong-Ho;Lee, Dae-Su;Kim, Il-Won;Song, Jae-Sung;Jeong, Soon-Jong;Lee, Jae-Shin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.317-321
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    • 2002
  • Piezoelectric properties of $(Pb_{1-x}Y_x)[(Ni_{1/3}Nb_{2/3})_{0.15}(Zr_{1/2}Ti_{1/2)})_{0.85}]O_{3}$ (x=0~0.05) ceramics were investigated, The stoichiometric PNN-PZT ceramics required the sintering temperature above $1100^{\circ}C$, but the addition of $Y_{2}O_{3}$ in the PNN-PZT ceramic lowered the sintering temperature down to $1000^{\circ}C$. In case of x=0.005, the electro-mechanical coupling $factor(K_p)$, the piezoelectric $constant(d_{33})$, and the maximum strain ratio of PNN-PZT ceramics sintered at $1000^{\circ}C$ were 53.1%, 395pC/N, and $2200{\times}10^{-6}$ respectively, A 30-layer piezoelectric actuator$(10{\times}10{\times}1.7mm)$ fabricated with the above material showed the maximum strain of $2.09{\mu}m$ under 100V DC bias.

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Determination of Adrenosterone and its Metabolites in Human Urine by LC/APCI/MS and GC/MS

  • Han, Eun-Jung;Yim, Ok-Kyoung;Beak, Sun-Young;Chung, Jae-Yeon;Lee, Ji-Hye;Kim, Jun-Gahn;Kim, Yun-Je
    • Bulletin of the Korean Chemical Society
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    • v.30 no.7
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    • pp.1489-1496
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    • 2009
  • This study was done for the determination and excretion profile of adrenosterone and its metabolites in human urine using both liquid chromatography with atmospheric pressure chemical ionization mass spectrometry and gas chromatography with mass spectrometry. Adrenosterone and its two metabolites were detected in human urine after administration a healthy volunteer with 75 mg of adrenosterone. We found that adrenosterone-M1 ($C_{19}H_{26}O_3$) was a reduction and adrenosterone-M2 ($C_{19}H_{26}O_4$) was a hydroxylation at C-ring, which did not know the exact position of the C-ring. The adrenosterone parent was detected by GC/TOF-MS, but not detected by LC/APCI/MS because of low intensity. Adrenosterone and its two metabolites were excreted as their glucuronided fractions. The recovery of this method ranged from 100.7 to 118.4% and the reproducibility and accuracy test were 85.5 to 112.0% and 1.1 to 8.4%, respectively. The excretion studies showed that adrenosterone and its metabolites were detectable in human urine during a 48 h period after oral administration, with maximum level of excretion at 4.1 h. The glucuro-/sulfaconjugated ratio of adrenosterone, M1 and M2 was 0.73 ${\pm}$ 0.03, 0.96 ${\pm}$ 0.06 and 0.89 ${\pm}$ 0.03 (n = 6), respectively. The amounts of adrenosterone excreted in urine were 14.75 ng for 48 h. Also, the maximum level of androsterone and 11$\beta$-hydroxy androsterone, which were endogenous steroids, were reached 4.1 h after the oral administration of adrenosterone.

Effect of Root-Zone Temperature in Hydroponics on Plant Growth and Nutrient Uptake in Vegetable Crops (수경재배(水耕栽培)에서 양액온도(養液溫度)가 채소작물(菜蔬作物)의 생장(生長) 및 무기양분흡수(無機養分吸收)에 미치는 영향(影響))

  • Jang, Byoung-Choon;Hong, Young-Pyo;Chun, Jae-Chul
    • Korean Journal of Soil Science and Fertilizer
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    • v.25 no.3
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    • pp.242-248
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    • 1992
  • This study was carried out to investigate the effects of root-zone temperature in hydroponics on the plant growth and nutrient uptake of lettuce(Lactuca sativa L), tomato (Lycopersicon esculentum Mill), and cucumber (Cucumis sativus L). Respiration rate in roots increased with increase in root-zone temperature. At $10^{\circ}C$ of root-zone temperature, respiration rate in lettuce root was higher than those in tomato and cucumber. Increasing rate of root respiration in tomato with increase in root-zone temperature was greater than those in lettuce and cucumber. The lowest dry weight and leaf area of the crops studied were obtained at $10^{\circ}C$ of root-zone temperature, but they were not different between 20 and $30^{\circ}C$. Increase in root-zone temperature generally resulted in increase in T/R ratio and net assimilation rate. At the low root-zone temperature, root growth and leaf area of tomato and cucumber were severely affected. Relative growth rates of lettuce and cucumber were also greatly reduced by the low root-zone temperature. Contents of N, P, K, Ca, and Mg in the crops increased as root-zone temperature increased from 10 to $20^{\circ}C$, whereas only Ca content in tomato and cucumber increased with increase in root-zone temperature to $30^{\circ}C$. Remarkably low contents of P and Mg in the crops were found at the low root-zone temperature. Inhibition of plant growth and nutrient uptake due to low root-zone temperature was much greater in cucumber than in lettuce and tomato.

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Evaluation of Chloride Behavior and Service Life in Long-Term Aged FA Concrete through Probabilistic Analysis (장기재령 FA 콘크리트에 대한 염화물 거동 및 확률론적 염해 내구수명 평가)

  • Yoon, Yong-Sik;Kwon, Seung-Jun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.8 no.3
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    • pp.276-285
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    • 2020
  • In this study, accelerated chloride diffusion tests were performed on OPC(Ordinary Portland Cement) and FA(Fly Ash) concrete considering three levels o f W/B(Water to Binder) ratio o n 1,095 curing days. The accelerated chloride diffusion coefficient and the passed charge were evaluated in accordance with Tang's method and ASTM C 1202, and the resistance performance to chloride attack improved over time. FA concrete showed excellent resistance performance against chloride penetration with help of pozzolanic reaction. As the result of the passed charge, FA concrete showed durability improvement, "low" grade to "very low" grade, but OPC concrete changed "moderate" grade to "low" grade at 1,095 curing days. After assuming the design variables used for durability design as normal distribution functions, the service life of each case was evaluated by the probabilistic analysis method based on MCS(Monte Carlo Simulation). In FA concrete, the increase of probability of durability failure was lower than that of OPC concrete with increasing time, because the time-dependent coefficient of FA concrete was up to 3.2 times higher than OPC concrete. In addition, the service life by probabilistic analysis was evaluated lower than the service life by deterministic analysis, since the target probability of durability failure was set to 10%. It is considered that more economical durability design will be possible if the mo re suitable target probability of durability failure is set for various structures through researches on actual conditions and indoor tests under various circumstances.

Effect of Forage Feeding Level on the Milk Production Characteristics of Holstein Lactating Cows (조사료 급여 수준이 Holstein 착유우의 산유 특성에 미치는 영향)

  • Lee, Bae Hoon;Nejad, Jalil Ghassemi;Kim, Hyeon Shup;Sung, Kyung Il
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.33 no.1
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    • pp.45-51
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    • 2013
  • This study was performed on two groups (10 cows) for primiparous Holstein lactating cows (av. 98 days in milk : DIM) which were divided into low forage diet (LF) and high forage diet (HF) groups based on forage : concentrate ratio (F : C ratio). The F : C ratios of LF and HF groups were 37:63 and 62:38, respectively. Concentrate intake was significantly higher in the LF group than the HF group whereas the HF group showed higher forage intake (12.9 kg) compared to the LF group (7.4 kg) (p<0.05). No significant difference was observed in total feed intake between the HF (20.9 kg) and LF (19.4 kg) group (p>0.05), but the HF group tended to be higher. CP, TDN and NEL intake showed no significant difference between the two groups (p>0.05). Though, there was no significant difference on actual milk between the two groups (26 vs. 23.9 kg/d, p>0.05), the LF group tended to be higher. 4% FCMs of LF and HF groups were 22.8 and 22.3 kg/d, respectively, and showed no significant difference (p>0.05). The HF group was higher in fat content and lower in MUN. C14:0, C16:0 and C16:1n7 of milk fatty acid were significantly higher in the HF group (p<0.05), but there were no differences in other milk fatty acids between the two groups. As a result, increasing high quality forage such as BIRG silage and hay in the diet will not only fulfill nutrient requirements but also reduce milk production.

Evolution of a Productive Bivoltine Hybrid of Silkworm Bombyx mori L.(SD7${\times}$SD12) with Shorter Larval Duration

  • Rao, P.Sudhakara;Basavaraja, H.K.;Kalpana, G.V.;Naik, V.Nishitha;Mahalingappa, K.C.;Pallavi, S.N.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.8 no.1
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    • pp.27-32
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    • 2004
  • With an objective of evolving quantitatively and qualitatively superior bivolitine silkworm hybrid of Bombyxmori L. for tropics with shorter larval duration without compromising on productivity traits, a breeding programme was initiated at this institute during 1997 by utilizing breeding resource material from the institutes Germplasm collection. The breed SD7 is characterized with plain larvae spinning white oval cocoons and SD12 is characterized by sex-limited larval markings spinning white dumb-bell cocoons. After fixation, these breeds along with other newly evolved breeds were subjected for hybrid evaluation in the laboratory. Based on the hybrid studies, the hybrid SD7${\times}$SD12 was selected and evaluated for one year comprising three major sea- sons (6 trials) of tropics viz., Pre-monsoon (characterized by high temperature, low humidity and without any rain fall), Monsoon (characterized by moderate temperature, heavy rain fall with high humidity) and post-monsoon season (characterized by low temperature and low humidity with frequent rain fall) to know the fluctuations in the larval duration. The evaluation studies indicated that the hybrid is having shorter larval duration with productive merits. The hybrid SD7${\times}$SD12 recorded survival percent of 92.74, shell weight of 46.7 cg, shell ratio % of 24.0 and filament length of 1,200 meters with a shorter larval duration of 24 hrs; when compared to productive hybrid CSR2${\times}$CSR5(control). The breeding methodologies and hybrids usefulness for tropics were discussed.

Sows fed with synergistic blend of short- and medium chain organic acid has a carryover effect on post-weaning growth rate

  • Sampath, Vetriselvi;Park, Jae Hong;Pineda, Lane;Han, Yanming;Cho, Sungbo;Kim, In Ho
    • Journal of Animal Science and Technology
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    • v.64 no.2
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    • pp.302-311
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    • 2022
  • This study investigated the effect of a synergistic blend of free and buffered organic acid (FMP) on the performance of piglets born to sows supplemented with a blend of short- and medium-chain organic acids (SGG) during the late gestation and lactation period. A total of 150 multiparous sows (n = 50/treatment, Landrace × Yorkshire) were blocked (2.4 parity) and assigned to 1 of 3 dietary treatments: CON - corn-soybean meal-based basal diet, SGG-Low - CON+ 1.5 kg/ton SGG, and SGG-High - CON + 3kg/ton SGG. During weaning, 600 piglets (6.72 ± 0.5kg) which weaned from sows supplemented with 3 levels of SGG were allocated to 2 weaner diets (Control and FMP - 3kg/ton) following 3 × 2 factorial arrangement. Supplemental effects on performance were measured at d0-d21 and d 21-42, and the entire period. Pigs fed with FMP and born to sows supplemented with SGG-High gained more weight and ate more (p < 0.05) compared with those in the CON group in both phases, and with SGG-Low in the second phase. Over the entire post-weaning period, piglets born to sows supplemented with SGG-Low and SGG-High had a higher average daily gain (ADG) and body weight (BW) (p < 0.05). Regardless of sow treatment, pigs fed with an FMP diet had higher ADG (p < 0.001), BW (p = 0.045), and a lower feed conversion ratio (p = 0.033). Also, feeding FMP diets reduced the fecal Escherichia coli and Clostridium perfringens counts at d42. The current study indicates that sows fed SGG supplement had a positive carry-over effect on the post-weaning growth rate, and FMP supplement enhances the growth performance and reduced the number of C. perfringens and E. coli. Thus, the application of 3 kg/ton of SGG in sows' diet and subsequent feeding of piglets with FMP would be an effective strategy to improve growth rate and reduce pathogenic bacteria in post-weaned piglets.

A Study on Application of SBR Process for RO Retentate Treatment (RO 농축수 처리를 위한 SBR 공정 적용에 관한 연구)

  • Kim, Il-Whee;Joo, Hyun-Jong
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.2
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    • pp.79-85
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    • 2012
  • In this study, Application of sequencing batch reactor (SBR) process for RO retentate treatment was performed. Efficiency of treatment by load and temperature variation was tested. The SBR process was operated two types as HRT per one cycle was 8 and 12 hours, respectively. Methanol was injected for an effective denitrificaion owing to low C/N ratio of the RO retentate. TN removal efficiency of the SBR process was relatively stable at the change of flow-rate and temperature. The optimum time cycle of SBR process was 2 cycle/day for TN removal, and in the case of 3 cycle/day, the effluent TN concentration was found under the effluent quality standard. In the result of assessment, the application of SBR process for RO retentate treatment was effective and could be utilized to design for the wastewater treatment plant. The specific nitrification rate (SNR) and specific denitrification rate (SDNR) were $0.043{\sim}0.066kg\;NH_3-N/kg\;MLVSS{\cdot}day$ and $0.096{\sim}0.287kg\;NH_3^--N/kg\;MLVSS{\cdot}day$, respectively. The derived kinetic could be applied for design to the aerobic and anoxic tank in the RO retentate treatment.

Comparison of the I-V Characteristic as Various Composition ratio of Iodine in a-Se of $BrO_2/a-Se$ based Radiation Conversion Sensor ($BrO_2/a-Se$ 구조의 방사선 변환센서에서 a-Se에 첨가된 조성비 변화에 따른 I-V 특성 비교)

  • Choi, Jang-Yong;Park, Ji-Koon;Gong, Hyun-Gi;Ahn, Sang-Ho;Nam, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.440-443
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    • 2002
  • Present1y the X-Ray diagnosis system is a real condition that is changing by digital ways in it's existent analog ways. This digital radiation detector is divided by the direct method and the indirect method. The indirect method of applied voltage has special qualities that the resolution is low than direct method by diffusion effect that happens. The conversion process ( radiation${\rightarrow}$visible ray${\rightarrow}$electrical signal of two times, has shortcomings that the energy conversion efficiency of electrical signal is low. The direct method has shortcomings that need strong electric fie1d to detect electrical signal efficiently. This research achieved to develop digital detector of the Hybrid method that have form that mixes two ways to supplement shortcoming of direct. indirect method. A studied electrical characteristic by Iodine's Mixture ratio change is added to selenium in the detector which has a multi-layer structure (Oxybromide + a-Se). There are 8 kinds of Manufactured compositions to amorphous selenium Iodine each 30ppm, 100ppm, 200 ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm by a doped photoconductor through a vacuum thermal evaporation method. The phosphor layer is consisted of Oxybromide ($BrO_2$) which uses optical adhesives multi-layer structure. The manufactured compositions calculates and compares Net Charge and signal to noise ratio measuring Photocurrent about Darkcurrent and X-ray. When doped Iodine Mixture ratio is 500ppm to the multi-layer structure (Oxybromide + a-Se), applied voltage of $3V/{\mu}m$, leakage current of compositions $2.61nA/cm^2$ and net charge value by 764pC/$cm^2$/mR then the best result appeared.

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