• 한국방사선학회논문지
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• 제2권1호
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• pp.31-34
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• 2008

The neutron capture spectrum for the light nuclide was very useful to study the nuclear structure. In the present study, the capture gamma-ray from the 27-keV resonance of $^{19}F(n,g)^{20}F$ reaction were measured with an anti-Compton NaI(Tl) spectrometer and the 3-MV Pelletron accelerator of the Research Laboratory for Nuclear Reactors at the Tokyo institute of technology. A neutron Time-of-Flight method was adopted with a 1.5 ns pulsed neutron source by the $^7Li(p,n)^7Be$ reaction. In the present experiment, a Teflon(($CF_2$)n) sample was used The sample was disk with a diameter of 90mm. The thickness of sample was determined so that reasonable counting rates could be obtained and the correction was not so large for the self-shielding and multiple scattering of neutrons in the sample, and was 5mm. The primary gamma-ray transitions were compared with previous measurement of Kenny.

• 환경위생공학
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• 제11권3호
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• pp.29-35
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• 1996

Numerical solutions were obtained to the model equations for various parameters characterizing the pore structure, effective internal diffusion and the chemical reaction constant. The conversion was decreased with the cause of pore closure at the surface of reacting particles, reduction of porosity, surface area of reaction and effective diffusion coefficient in the solid with the progress of reaction. Total conversion was strongly depend on the local conversion at surface. According to the decreasing of impregnated concentration of the copper oxide and the increase of the flue gases concentration, total conversion was increased. And the conversion were affected by gas flow rate and pore size distribution of the reacting solid.

• Bulletin of the Korean Chemical Society
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• 제7권3호
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• pp.235-237
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• 1986

Reaction of $(E)-{\beta}-chloro-{\gamma}$-hydroxyvinylmercurials, prepared by mercuration of propargyl alcohol and 2-methyl-3-butyne-2-ol, with olefins in the presence of a catalytic amount of $Li_2PdCl_4$ and 2 equiv of cupric chloride in methanol at $50^{\circ}C$ gave the corresponding (E,E)-2,4-dienols in moderate yields. However, addition of 1 equiv of inorganic bases such as magnesium oxide to the reaction mixture brings a rapid and clean vinylation and gave high yields of the dienols at room temperature. In the case of hindered (E)-2-chloro-3-chloromercuri-2-buten-1,4-diol prepared from 2-butyne-1,4-diol, reaction with olefins gave the dienols only in low yields even in the presence of 2 equiv of magnesium oxide.

• Archives of Pharmacal Research
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• 제27권11호
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• pp.1099-1105
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• 2004

The peroxisome proliferator-activated receptors (PPARs) are a primary regulator of lipid metabolism. Potency for activation of PPAR$\gamma$, one of a subfamily of PPARs, particularly mirrors glucose lowering activity. We prepared thiazolidinediones featuring benzoxazole moiety for subtype selective PPAR$\gamma$ activators. 5-[4-[2-(Benzoxazol-2-yl-alkylamino)ethoxy]benzyl]thiazolidine-2,4-diones have been prepared by Mitsunobu reaction of benzoxazolylalkylaminoethanol 8 and hydroxybenzylthiazolidinedione 6 and their activities were evaluated. Most compounds tested were identified as potent PPAR$\gamma$ agonists.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.424-425
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• 2006

The effects of reaction temperature and precursor concentration on the microstructure and magnetic properties of ${\gamma}-Fe_2O_3$ nanoparticles synthesized as final products of iron acetylacetonate in chemical vapor condensation (CVC) were investigated. Pure ${\gamma}-Fe_2O_3$ phase was obtained at temperature above $900^{\circ}C$ and crystallite size of ${\gamma}-Fe_2O_3$ nanoparticles decreased with lowering precursor concentration. Also, the coercivity decreases with decreasing crystallite size of nanopowder. The lowest coercivity was 7.8 Oe, which was obtained from the ${\gamma}-Fe_2O_3$ nanopowder sample synthesized at precursor concentration of 0.3M. Then, the crystallite size of ${\gamma}-Fe_2O_3$ nanoparticles was 8.8 nm.

• 대한화학회지
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• 제8권2호
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• pp.85-87
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• 1964

Alloxan에 의한 Amino acids의 spot test에 있어서, alloxan수용액에 lactose를 가해주면, alloxan 자신의 착색을 막을 수 있다. lactose를 포함하는 alloxan수용액은 매우 안정하여서, 실온에서 수 개월 동안 두어도 착색되지 않으며, lactose의 존재로 말미암아, alloxan과 amino acids와의 색반응은 조금도 영향을 받지 않았다. 이시약에 의한 amino acids의 spot test법은 ninhydrin에 의한 spot test보다 예민하고, 또 alloxan 또는 dimethylalloxan을 발색약으로 사용하는 paper chromatography법에 비해, proline (1 ${\gamma}$), hydroxyprolin (5 ${\gamma}$)를 확인할 수 있다는 장점을 가지고 있다.

• Nuclear Engineering and Technology
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• 제32권4호
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• pp.361-371
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• 2000

The 123Te(p,n)123I, 124Te(p,n)124I and 124Te(p,2n)123I reactions, among the many reaction channels opened, are the major reactions under consideration from a diagnostic purpose because reaction residuals as the gamma emitters are used for most radiophamaceutical applications involving radioiodine. Based on the available experimental data, the absorption cross sections and elastic scattering angular distributions of the proton-induced nuclear reaction on Te isotopes below 60 MeV are calculated using the optical model code APMNK. The transmission coefficients of neutron, proton, deuteron, trition and alpha particles are calculated by CUNF code and are fed into the GNASH code. By adjusting level density parameters and the pair correction values of some reaction channels, as well as the composite nucleus state density constants of the pre-equilibrium model, the production cross sections and energy-angle correlated spectra of the secondary light particles, as well as production cross sections and energy distributions of heavy recoils and gamma rays are calculated by the statistical plus pre-equilibrium model code GNASH. The calculated results are analysed and compared with the experimental data taken from the EXFOR. The optimized global optical model parameters give overall agreement with the experimental data over both the entire energy range and all tellurium isotopes.

• 한국가스학회지
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• 제20권2호
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• pp.1-9
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• 2016

본 연구는 플라즈마/촉매 공정을 이용하여 n-헵테인과 일산화탄소의 동시제거에 대해 조사하였다. n-헵테인과 일산화탄소의 분해특성을 파악하기 위해 플라즈마/촉매 공정과 촉매공정의 분해효율을 비교하였고, 촉매의 종류, 온도, 전력 등을 변화시켜 실험을 진행하였다. n-헵테인의 분해효율은 반응기 내부의 온도보다는 에너지밀도에 더 영향을 많이 받는 것으로 확인되었으며, 일산화탄소는 에너지밀도와 반응기 내부 온도 모두의 영향을 받는 것으로 나타났다. 촉매의 종류를 달리하며 n-헵테인의 분해효율을 조사한 결과 $Pd/{\gamma}-Al_2O_3$ > $Ru/{\gamma}-Al_2O_3{\approx}Ag/{\gamma}-Al_2O_3$순으로 나타났다. 특히, $Pd/{\gamma}-Al_2O_3$를 사용한 경우 n-헵테인 분해 과정에서 일산화탄소가 거의 발생하지 않았으며, $CO_2$ 선택도가 100%에 가까웠다. 일산화탄소 분해효율은 $Pd/{\gamma}-Al_2O_3$ > $Ru/{\gamma}-Al_2O_3$ > $Ag/{\gamma}-Al_2O_3$ 순으로 나타났으며, $180^{\circ}C$이하의 온도에서는 플라즈마/촉매 공정의 효율이 높고, $180^{\circ}C$이상에서는 촉매 공정의 분해효율이 높았다.

• 한국자기학회지
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• 제2권1호
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• pp.8-14
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• 1992

${\gamma}-Fe_{2}O_{3}$ 입자의 보자력 특성을 향상시키기 위해 ${\gamma}-Fe_{2}O_{3}$ 입자표면상에 코발트 훼라이트를 결정화시켜 코발트 에피탁시얼 ${\gamma}-Fe_{2}O_{3}$ 입자를 제조하 였다. 피착층인 $Co_{x}Fe_{3-x}O_{4}$의 보자력은 x=1인 조성에서 가장 우수한 특성을 나타내었다. 반응 분위기를 초기 비산화성에서 산화성 분위기로 제어하여 제조한 시료의 자기 특성이 가장 우수하였으며 반응온도 $90^{\circ}C$에서 30분간 반응하면 ${\gamma}-Fe_{2}O_{3}$ 입자표면상에서의 코발트 훼라이트 피착 반응이 완료되었다.

• 한국식품영양과학회지
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• 제35권5호
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• pp.583-587
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• 2006

당 및 lysine 혹은 당-lysine 혼합모델 수용액에서 감마선 조사에 의한 갈변도 변화 및 화학적 특성을 연구한 결과 감마선 조사에 의한 비효소적 갈변반응은 당 및 아미노산 단독 환경에서는 일어나지 않았으며, 당-아민 환경에서 진행되는 것으로 나타났다. 당-lysine 혼합용액의 감마선 조사에 의한 갈변 반응성은 당의 종류에 따라 다르게 나타났으나, 당의 감소와 갈변도 사이의 상관관계는 없었다. 비환원당인 sucrose는 감마선 조사에 의해 환원력이 생성되었으며, 다른 당에 비해 높은 갈변 반응성을 나타냈다.