• Animal Bioscience
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• 제36권3호
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• pp.492-497
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• 2023

Objective: The objectives were to demonstrate that the nitrogen and energy in pig urine supplemented with hydrochloric acid (HCl) are not volatilized and to determine the minimum amount of HCl required for nitrogen preservation from pig urine. Methods: In Exp. 1, urine samples of 3.0 L each with 5 different nitrogen concentrations were divided into 2 groups: 1.5 L of urine added with i) 100 mL of distilled water or ii) 100 mL of 6 N HCl. The urine in open plastic containers was placed on a laboratory table at room temperature for 10 d. The weight, nitrogen concentration, and gross energy concentration of the urine samples were determined every 2 d. In Exp. 2, three urine samples with different nitrogen concentrations were added with different amounts of 6 N HCl to obtain varying pH values. All urine samples were placed on a laboratory table for 5 d followed by nitrogen analysis. Results: Nitrogen amounts in urine supplemented with distilled water decreased linearly with time, whereas those supplemented with 6 N HCl remained constant. Based on the linear broken-line analysis, nitrogen was not volatilized at a pH below 5.12 (standard error = 0.71 and p<0.01). In Exp. 3, an equation for determining the amount of 6 N HCl to preserve nitrogen in pig urine was developed: additional 6 N HCl (mL) to 100 mL of urine = 3.83×nitrogen in urine (g/100 mL)+0.71 with R² = 0.96 and p<0.01. If 62.7 g/d of nitrogen is excreted, at least 240 mL of 6 N HCl should be added to the urine collection container. Conclusion: Nitrogen in pig urine is not volatilized at a pH below 5.12 at room temperature and the amount of 6 N HCl required for nitrogen preservation may be up to 240 mL per day for a 110-kg pig depending on urinary nitrogen excretion.

• 한국세라믹학회지
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• 제39권6호
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• pp.594-597
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• 2002

플라즈마 화학기상증착(PECVD)법을 이용하여 p-type Si(100) 웨이퍼에 Silicon Oxynitride(SiON) 후막을 SiH$_4$ , $N_2$O, $N_2$ 가스를 혼합하여 증착하였다. Prism coupler측정을 통해 SiON 후막의 굴절률 1.4620~1.5312을 얻었으며, rf power가 180 W에서 5.92$\mu$m/h의 증착률을 나타내었다. 증착변수에 따른 화학적 조성의 영향은 X-ray Photoelectron Spectroscopy(XPS) 을 통하여 관찰하였다. 또한, SiON 후막 증착후에 $1.5\mu$m 부근의 흡수띠를 제거하기 위해 105$0^{\circ}C$의 $N_2$ 분위기에서 2시간 동안 열처리를 행하였다.

• Bulletin of the Korean Chemical Society
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• 제29권3호
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• pp.585-589
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• 2008

Second-order rate constants (kN) have been measured for reactions of Y-substituted phenyl 2-thiophenecarboxylates (6a-h) with morpholine and piperidine in 80 mol % H2O/20 mol % DMSO at 25.0 0.1 oC. The Brnsted-type plot for the reactions of 6a-h with morpholine is linear with b lg = 1.29, indicating that the reactions proceed through a tetrahedral zwitterionic intermediate (T?). On the other hand, the Brnsted-type plot for the reactions of 6a-h with piperidine exhibits a downward curvature, implying that a change in the rate-determining step occurs on changing the substituent Y in the leaving group. Dissection of kN into microscopic rate constants (i.e., k1 and k2/k1 ratio) has revealed that k1 is smaller for the reactions of 6a-h than for those of Y-substituted phenyl 2-furoates (5a-h), while the k2/k1 ratio is almost the same for the reactions of 5a-h and 6a-h. It is also reported that modification of the nonleaving group from the furoyl (5a-h) to the thiophenecarbonyl (6a-h) does not influence pKao (defined as the pKa at the center of the Brnsted curvature) as well as the k2/k1 ratio.

• 한국동물위생학회지
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• 제42권3호
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• pp.135-144
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• 2019

Low pathogenic avian influenza (LPAI; H9N2) and Newcastle disease (ND) are economically important poultry diseases in Korea. In this study, we investigated pathological features and virus distribution in the lymphoid tissues of chicks experimentally infected with H9N2 and/or ND virus. Six-weeks-old SPF chickens were divided into 4 groups, Control (C), H9N2 (E1), NDV (E2), and H9N2+NDV (E3). E1 group was challenged with 0.1 ml A/Kr/Ck/01310/01 (H9N2) $10^{5.6}$ $EID_{50}$ intranasally, E2 group was challenged with 0.5 ml KJW (NDV) $10^{5.0}{\sim}10^{6.0}$ $ELD_{50}$ intramuscularly, and E3 group was challenged with H9N2, followed 7 days later by NDV. In histopathological examination, E1 group showed depletion and necrosis in bursa of Fabricius, thymus, cecal tonsil, and spleen, whereas E2 and E3 groups were noted severe lymphocyte depletion and necrosis with destruction of lymphoid organs structures. In TUNEL assay, apoptotic bodies were detected in lymphoid organs of all experimental groups, which was most severe in E3 group. H9N2 and ND viruses were predominantly detected in cecal tonsil of E1, E2, and E3 groups by PCR and immunohistochemistry (ICH). In conclusion, co-infection of H9N2 with NDV caused severe pathologic lesions and apoptosis in lymphoid tissues compared to single infections.

• Bulletin of the Korean Chemical Society
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• 제16권1호
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• pp.26-29
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• 1995

Six-coordinate molybdenum(Ⅴ)-oxo complexes (PyH)[MoOCl2L] and (R4N)-[MoOCl2L] (R=CH3 and C2H5) with N-salicylidene-2-aminophenol(L1) and its derivatives(L2=5-CH3, L3=3-CH3O, L4=5,6-C4H4 and L5=5-NO2) as ONO-donor ligands have been synthesized and the spectral and electrochemical properties of the complexes by elemental analysis, molar conductivity, UV-vis, IR, 1H NMR and CV have been studied.

• Nuclear Engineering and Technology
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• 제16권2호
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• pp.58-63
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• 1984

특별히 제작한 영동장치를 써서 8면체 구조의 (Ruc $l_{6}$)$^{3-}$ 를 여과지 전기영동 분리하였다. 자지전해질 용액은 다음과 같다. 0.1M-HCl $O_4$, 0.05M-HCl+0.09M-KCI, 0.1M-HCl, 5$\times$$10^{-3}$M-NTA, 0.01M-HCl, 0.01M-HCl $O_4$, 0.01M-시트르산, 0.01M-K $H_2$P $O_4$+0.01M-$Na_2$HP $O_4$, 0.05M-붕사, 0.025M-$Na_2$C $O_3$+0.025M-NaHC $O_3$, 0.01M-$Na_3$P $O_4$, 0.01M-NaOH, 0.1M-NaOH. (Ruc $l_{6}$)$^{3-}$ 은 2-4피크로 나타내며 다음 화학종으로 확인된다. (RuCl($H_2O$)$_{5}$ )$^{2+}$, cis- 및 trans-(RuC $l_2$($H_2O$)$_4$)$^{1+}$ , (RuC $l_3$($H_2O$)$_3$)$^{0}$ , (RuC $l_4$($H_2O$)$_2$)$^{1-}$, (RuC $l_{5}$ ($H_2O$))$^{2-}$ , (RuC $l_{6}$)$^{3-}$ . 리텐숀 값은 0.025M-$Na_2$C $O_3$+0.025M-NaHC $O_3$ 전해질 용액에서 가장 높다.

• Journal of Advanced Marine Engineering and Technology
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• 제36권5호
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• pp.574-579
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• 2012

본 논문에서는 $CO_2-C_2H_6-N_2$와 $CO_2-N_2$를 각각 적용한 캐스케이드 액화사이클을 새롭게 제안하고, HYSYS를 이용하여 이에 대한 성능 및 엑서지를 분석한 후, 이 사이클이 LNG-FPSO선에 적용가능여부를 확인하였다. 그 분석 결과로부터, 효율적인 측면에서는 $CO_2-C_2H_6-N_2$ 액화사이클이 우수하였고, 엑서지 손실측면에서는 장치 수가 적은 $CO_2-N_2$ 액화사이클이 오히려 높게 나왔다. 그리고 $CO_2-N_2$ 냉매용액화사이클은 기존의 $C_3H_8-C_2H_4-C_1H_4$ 보다 낮은 효율과 높은 압축일량을 보였다. 하지만, $N_2$ 사이클의 효율이 더 개선된다면 액화사이클의 구조가 간단하기 때문에 LNG-FPSO용 액화사이클로서 적합할 것으로 생각된다.

• 생명과학회지
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• 제25권5호
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• pp.496-506
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• 2015

본 연구는 바이오플락을 기반으로 한 무 환수 사육 시스템에서 안정된 수질을 유지하기 위한 적정 수온 범위를 조사하였다. 이를 위해 다음과 같이 수온에 대한 5개의 실험 수조를 설정하였다: 10℃, 15℃, 20℃, 25℃ 그리고 30℃. 우선 각각의 실험 수조에 바이오플락을 기반으로 한 사육시스템을 조성하고, 조성된 각 실험 수조에 금붕어를 수용하여 사육수를 교환하지 않고 60일 동안 사육하였다. 바이오플락 기반 사육시스템이 조성되고, 무기 질소화합물들($NH_4{^+}-N$, $NO_2{^-}-N$, 그리고 $NO_3{^-}-N$)의 농도가 안정되게 낮은 상태는 10℃, 15℃, 20℃, 25℃, 30℃에서 각각 17, 26, 43, 68, 그리고 78일 이후에 유지되었다. 바이오플락 기반 사육 수조에 금붕어를 사육하기 시작하면서 $NH_4{^+}-N$ 농도가 10℃와 15℃에서는 지속적으로 낮은 상태가 유지되었으나, 20℃, 25℃ 그리고 30℃에서는 점진적 으로 증가하였다. 10℃와 15℃에서 $NO_2{^-}-N$과 $NO_3{^-}-N$의 농도는 낮은 상태가 유지되지 않고 바로 증가하였다. 반면, 20℃ 이상에서 $NO_2{^-}-N$의 농도는 지속적으로 비교적 안정되게 낮은 농도를 유지하였으며, $NO_3{^-}-N$의 농도는 점진적으로 증가하였다. 바이오플락 기반 수조에서 15℃ 이하의 조건에서는 $NO_2{^-}-N$ 농도를 낮고 안정된 상태를 유지할 수 없었다. 20℃ 이상에서 pH와 NH₄⁺-N 농도 사이의 역상관관계가 pH 4.0과 6.0 사이에서 나타났다. pH 4.0과 6.0 범위에서 $NH_4{^+}-N$ 농도가 감소함에 따라 pH는 증가하였다. 그러나 pH 6.0과 8.0 사이에서는 pH와 $NH_4{^+}-N$ 농도 간 상관관계가 없었었으며, pH 6.0 이상에서는 $NH_4{^+}-N$ 농도가 지속적으로 낮은 상태를 유지하였다. 이러한 결과는 20℃ 이상에서 $NH_4{^+}-N$ 농도를 낮고 안정된 상태로 유지하기 위해서는 pH를 6.0 이상 유지해야만 한다는 것을 보여준다.

• 한국대기환경학회지
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• 제13권5호
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• pp.397-410
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• 1997

An annular denuder filter pack sampling system (ADS) was used to collect acidic air pollutants in Pusan. During the study period (from June 1995 to November 1995), forty eight samples were collected every 12 hours starting from 6:00 in the morning. These samples were devided into two sets of data for day (6:00 a.m.-6:00 p.m.) and night (6:00 p.m.-6:00 a.m.). The chemical species were analyzed for HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$ in the gas Phase, and N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$ and N $H_4$$^{+}$ in the particulate phase. The mean concentrations measured from this study were 0.24, 1.91, 30.07 and 4.24 $\mu\textrm{g}$/㎥ for HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$, respectively. The mean concentrations of N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$ and N $H_4$$^+{\ulcorner}$ were 1.95, 7.36 and 3.48 $\mu\textrm{g}$/㎥, respectively. The mean concentrations of gaseous species except for HN $O_2$ were higher in daytime than in nighttime, but the reverse was true in the particulates except for N $H_4$$^{+}$. +/..

• 약학회지
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• 제35권4호
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• pp.288-294
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• 1991

A new fluorescent derivatizing reagent was developed to be used in HPLC for the trace determination of primary and secondary amines. This new reagent, 1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride, was synthesized by the chlorination of sodium 1-(N,N-dimethylamino)pyrene-6-sulfonate which was obtained from 1-(N,N-dimethylamino)pyrene after sulfonation. Ephedrine and norephedrine were derivatized quantitatively by this reagent. The optimum conditions for the derivatization such as pH, reagent concentration, reaction time and reaction temperature ware examined. The structures of derivatives were identified by IR, $^{1}$H-NMR and MS methods. The fluorescence properties and the stability of the derivatives were examined. The derivatives were separated on silica column with an isocratic elution using the mixture of n-hexane and ethylacetate and monitored by fluorescene detector. Linear calibration curves were obtained and detection limits in a 10 $\mu$l injection volume were 5 picomole for ephedrine and norephedrine.