• 한국분말재료학회지
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• 제13권5호
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• pp.327-335
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• 2006

In the development of new hydrogen absorbing materials for a next generation of metal hydride electrodes for rechargeable batteries, metastable Mg-Ni-based compounds find currently special attention. Amor phous-nanocrystalline $Mg_{63}Ni_{30}Y_7$ and $Mg_{50}Ni_{30}Y_{20}$ alloys were produced by mechanical alloying and melt-spinning and characterized by means of XRD, TEM and DSC. On basis of mechanically alloyed Mg-Ni-Y powders, complex hydride electrodes were fabricated and their electrochemical behaviour in 6M KOH (pH=14,8) was investigated. The electrodes made from $Mg_{63}Ni_{30}Y_7$ powders, which were prepared under use of a SPEX shaker mill, with a major fraction of nanocrystalline phase reveal a higher electrochemical activity far hydrogen reduction and a higher maximum discharge capacity (247 mAh/g) than the electrodes from alloy powder with predominantly amorphous microstructure (216 mAh/g) obtained when using a Retsch planetary ball mill at low temperatures. Those discharge capacities are higher that those fur nanocrystalline $Mg_2Ni$ electrodes. However, the cyclic stability of those alloy powder electrodes was low. Therefore, fundamental stability studies were performed on $Mg_{63}Ni_{30}Y_7$ and $Mg_{50}Ni_{30}Y_{20}$ ribbon samples in the as-quenched state and after cathodic hydrogen charging by means of anodic and cathodic polarisation measurements. Gradual oxidation and dissolution of nickel governs the anodic behaviour before a passive state is attained. A stabilizing effect of higher fractions of yttrium in the alloy on the passivation was detected. During the cathodic hydrogen charging process the alloys exhibit a change in the surface state chemistry, i.e. an enrichment of nickel-species, causing preferential oxidation and dissolution during subsequent anodization. The effect of chemical pre-treatments in 1% HF and in $10\;mg/l\;YCl_3/1%\;H_2O_2$ solution on the surface degradation processes was investigated. A HF treatment can improve their anodic passivation behavior by inhibiting a preferential nickel oxidation-dissolution at low polarisation, whereas a $YCl_3/H_2O_2$ treatment has the opposite effect. Both pre-treatment methods lead to an enhancement of cathodically induced surface degradation processes.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1321-1321
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• 2006

• 산업식품공학
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• 제13권3호
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• pp.203-210
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• 2009

본 연구는 마요네즈 제조 시 유화제로 사용되고 있는 난황이 콜레스테롤을 다량 함유하고 있는 점을 개선하기 위하여 난황 대신 두유를 사용하였고, 된장의 항산화 효과로 인해 마요네즈의 저장성을 증진시켜줄 수 있을 것이라는 점에 착안하여, 유화제 종류와 된장분말 첨가가 마요네즈의 품질특성을 증진시킬 수 있는지 조사하고자 시행하였으며 그 결과는 다음과 같다. 1) 총 페놀함량은 E1이 97.92 mg%, E2는 131.15 mg%, E3는 172.81 mg%로 증가되었고, S1은 56.87 mg%, S2는 111.39 mg%, S3는 152.75 mg%로 된장분말의 첨가량이 증가할수록 증가하였다(p<0.001). 2) 전자공여능은 E1이 20.49%에서 E2는 34.32%, E3는 50.95%로 증가되었고, S1은 9.59%, S2는 16.02%, S3는 38.77%로 된장분말의 첨가량이 증가할수록 증가하였다 (p<0.001). 총 페놀함량과 전자공여능 측정 결과 된장분말을 6% 함유한 E3, S3에서 높게 나타났다. 3) 색도 측정 결과 L값(명도)은 E군이 S군보다 높게 나타났다. a값(적색도)는 S군이 높았고, b값(황색도)는 E군이 높게 나타났다. 된장분말이 증가할수록 L값(명도)은 감소하였고, a값(적색도)과 b값(황색도)는 증가하였다(p<0.001). 4) 콜레스테롤 함량은 E군이 152.87-156.62 mg/100 g, S군은 2.87-8.29 mg/100 g으로 나타나 두유로 만든 마요네즈의 콜레스테롤 함량이 매우 낮았다(p<0.001). 5) 관능검사 결과는 된장분말의 첨가량이 증가할수록 색의 점수는 낮았고 신맛, 짠맛, 발림성은 증가하였다. E군은 S군보다 기름 냄새와 느끼한 맛이 강한 것으로 나타났다. 관능검사의 전반적인 결과로 볼 때 향, 전체적인 맛, 전체적인 기호도에서 된장분말 3%를 함유한 두유마요네즈 S2가 가장 적당한 마요네즈라고 사료된다. 연구 결과를 종합해 보면 난황 대신 두유를 사용하고 된장을 3% 첨가한 마요네즈에서 관능검사 시 높은 점수를 나타냈고, 콜레스테롤은 150 mg/100 g에서 10 mg/100 g로 낮출 수 있었다. 비록 두유보다 난황을 사용한 마요네즈가 더 높은 항산화성을 나타내었지만 저장성 실험을 한 결과 두유마요네즈가 더 높은 저장성을 보였다. 이와 같은 마요네즈가 개발된다면 계란의 난황 대신 두유를 사용하여 콜레스테롤 함유량을 낮출 수 있으며 계란 알레르기를 가지고 있는 환자들에게 도움을 줄 것이다. 그리고 된장 분말이 항산화작용을 하는 점을 이용하여 식품의 보존제로 첨가하여 식용유지의 산화를 방지하고 우리의 전통 발효식품인 된장을 서양요리에 접목 시킬 수 있어 우리나라 전통 발효식품인 된장을 세계화시키는데 기여할 수 있을 것으로 기대된다.

• 한국재료학회지
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• 제24권5호
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• pp.255-258
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• 2014

Zirconium boride is an artificial or which is rarely found in the nature. $ZrB_2$ is popular in the hard material industry because it has a high melting point, excellent mechanical properties and chemical stability. There are two known methods to synthesize $ZrB_2$. The first involves direct reaction between Zr and B, and the second is by reduction of the metal halogen. However, these two methods are known to be unsuitable for mass production. SHS(Self-propagating High-temperature Synthesis) is an efficient and economic method for synthesizing hard materials because it uses exothermic reactions. In this study, $ZrB_2$ was successfully synthesized by subjecting $ZrO_2$, Mg and $B_2O_3$ to SHS. Because of the high combustion temperature and rapid combustion, in conjunction with the stoichiometric ratio of $ZrO_2$, Mg and $B_2O_3$; single phase $ZrB_2$ was not synthesized. In order to solve the temperature problem, Mg and NaCl additives were investigated as diluents. From the experiments it was found that both diluents effectively stabilized the reaction and combustion regime. The final product, made under optimum conditions, was single-phase $ZrB_2$ of $0.1-0.9{\mu}m$ particle size.

• 한국식품조리과학회지
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• 제31권6호
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• pp.733-740
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• 2015

This study was performed to examine the functional and quality characteristics of rice cookies with added Ligularia fischeri (Ledeb.) Turcz. powder. Rice cookies were prepared with different amounts (0%, 0.5%, 1%, 1.5% and 2% to the flour quantity) of Ligularia fischeri powder. The antioxidant activities of Ligularia fischeri powder, specifically the total phenolic content, DPPH free radical scavenging activity and reducing power were found to be 212.19 mg GAE/g, $11.78{\mu}g/mL$11.78 ($IC_{50}$), and 2.33 (O.D.), respectively. The antioxidant activities of the rice cookies with added Ligularia fischeri powder increased with increasing concentrations of Ligularia fischeri powder. Regarding the hunter's color value of rice cookies with added Ligularia fischeri powder, L (lightness) and a (redness) values decreased (p<0.001) with increasing concentrations of Ligularia fischeri powder, whereas b (yellowness) values increased (p<0.01). The consumer acceptability score for the 3% Ligularia fischeri rice cookie groups ranked significantly (p<0.001) higher than the other groups in color, flavor, taste, texture and overall preference. These results suggest that Ligularia fischeri powder will be useful as a functional food resource with antioxidant activities.

• 한국세라믹학회지
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• 제50권3호
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• pp.195-200
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• 2013

Here, we report preparation of cyan ceramic nano-pigment for inkjet printing and the Ni substitutional effects on the cyan color. $MgAl_2O_4$ was selected as the crystalline host network for the synthesis of nickel-based cyan ceramic nano-pigments. Various compositions of $Ni_xMg_{1-x}Al_2O_4$ ($0{\leq}x{\leq}1$) powders were prepared using the polymerized complex method. The powder was then preheated at $400^{\circ}C$ for 5 h and finally calcined at $1000^{\circ}C$ for 5 h. XRD patterns of $Ni_xMg_{1-x}Al_2O_4$ showed a single phase of the spinel structure in all the compositions. The particle sizes ranged from 20 to 50 nm in TEM observations. The characteristics of the color tones of $Ni_xMg_{1-x}Al_2O_4$ were analyzed by UV-Visible spectroscopy and CIE $L^*a^*b^*$ measurement. CIE $L^*a^*b^*$ measurement results indicate that the pigment color changes from light cyan to deep cyan due to the decrease of the $a^*$ and $b^*$ values with an increase of an Ni substitutional amount. In addition, the thermal stability and the binding nature of $Ni_xMg_{1-x}Al_2O_4$ are also discussed using TG-DSC and FT-IR results respectively.

• BMB Reports
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• 제30권1호
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• pp.73-79
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• 1997

This study was designed to investigate the effects of dietary garlic powder on cytochrome P450 enzymes and membrane stability in murine hepatocarcinogenesis initiated by diethylnitrosamine (DEN). Male Sprague-Dawley rats received a single intraperitoneal injection of DEN (200 mg/kg body wt) dissolved in saline. After 2 weeks on a basal diet, animals were fed diets containing 0. 0.5. 2.0. or 5.0% garlic powder for 6 weeks, and were subjected to two-thirds partial hepatectomy. The areas of placental glutathione S-transferase (GST-P) positive foci were inhibited in rats fed with garlic diets. GST-P is the most effective marker for DEN-initiated lesions. Hepatic microsomal lipid peroxidation was significantly decreased in rats fed with 2.0 and 5.0% garlic powder diets compared with that observed in the control animals and hepatic microsomal glucose 6-phosphatase (G6Pase) activity was found to increase significantly in rats fed 0.5 and 2.0% garlic powder diets. Thus as little as 0.5% garlic powder has a positive effect on the stability of hepatic microsomal membranes. p-Nitrophenol hydroxylase (PNPH) activity and the level of cytochrome P450 2E1 protein in the hepatic microsomes from rats fed diets containing 2.0 and 5.0% garlic powder were much lower than those of control microsomes. Rats fed 5.0% garlic powder diets exhibited the lowest P450 2E1 activity and protein levels among groups. Pentoxyresorufin O-dealkylase activity and immunoblot (cytochrome P450 2B1) analyses were not different between groups. However, the levels of cytochrome P450 1A1/2 protein in rats fed 0.5 and 2.0% garlic powder were significantly induced compared to controls. These results suggest that 2.0% garlic powder is effective in inhibiting the areas of GST-P positive foci, modulating certain isoforms of cytochrome P450 enzymes and stabilizing the hepatic microsomal membrane. Thus, the selective modification of cytochrome P450 enzymes and membrane stability by dietary garlic powder may influence areas of GST-P positive foci and chemoprevention of post-initiation of rat hepatocarcinogenesis.

• 한국토양비료학회지
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• 제45권2호
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• pp.162-168
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• 2012

친환경 선충 방제제 개발을 위해 경북 성주군 선남면 및 충남 공주군 우성면의 시설원예 재배지 토양으로 부터 선충 포식성이 뛰어난 곰팡이 Arthrobotrys thaumasia Nema-1과 선충 표피성분인 collagen과 알집 주성분인 gelatin 분해능이 뛰어난 Bacillus subtilis C-9를 분리 하였다. 이들 분리균을 대상으로 포트실험을 통해 선충치사 효과의 지표인 난낭수 감소를 검토한 결과, 균밀도가 $7.0{\times}10^3cfu\;g^{-1}$인 A. thaumasia Nema-1 곰팡이 제제 $5,000mg\;kg^{-1}$을 처리 시 뿌리혹 선충의 난낭수가 무처리 대비 35% 감소하였다. 포식성 곰팡이 Nema-1 제제와 균밀도가 $8.5{\times}10^5cfu\;g^{-1}$인 B. subtilis C-9 세균 제제 각각 $5,000mg\;kg^{-1}$ 혼합 처리구에서는 난낭수가 무처리 대비 67% 감소하였다. 또한 선충치사효과를 증진시키기 위하여 살선충 활성이 있다고 보고 된 계피추출물 제제 $10mg\;kg^{-1}$을 $5,000mg\;kg^-$의 Nema-1과 C-9 제제와 혼합하여 처리 하였을 때 난낭수가 무처리 대비 84%이상 감소하였으며, 대표적 살선충제인 선충탄(Fosthiazate) $24mg\;kg^{-1}$은 난낭수가 26% 감소한 결과와 비교해 볼 때 훨씬 높은 수준이었다. 이상의 결과는 생물학적 선충방제제는 미생물 또는 식물체 추출물 단제 보다는 혼합물 형태로 사용하는 것이 더 효과적이라는 결과를 제시하였다.

• Journal of Animal Science and Technology
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• 제47권2호
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• pp.233-242
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• 2005

Effects of supplemental charcoal powder and vitamin A on growth performance, serum profile and carcass characteristics with 24 Hanwoo steers were inves$\ell$ated. The Hanwoo steers were randomly assigned to one of the three dietary treatments: 1) Control(commercial feed), 2) Tl(commercial feed supplemented with 2% charcoal powder and 0.2 % vitamin A), 3) T2(commercial feed with 2 % charcoal powder). In the age 26 month, body weight of control Tl and T2 were 633.8 kg, 621.0 kg, 619.4 kg, respectively, with not significantly different(P> 0.05). The daily weight gain of control was the highest followed by Tl and T2. The contents of vitamin A(retinol) and total cholesterol in the blood of Tl was higher Tl(56.32 $\ell$ / dt, 163.83 mg/ dz) than the other treatment groups(P < 0.05). The average of WBC value in the blood was 6.86-" 9.83 k / ${\mu}\ell$, RBC value was 7.98 - 11.26 k / ${\mu}\ell$ and blood platelet was 236.7 - 287.0 k / ${\mu}\ell$. But The serum profile in blood was not significantly different between control and treatment groups. The carcass grade and characteristics of all treatments in Hanwoo steers were not significantly different except the texture.

• 생명과학회지
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• 제12권6호
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• pp.654-660
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• 2002

본 연구는 들깻잎 첨가와 도체 등급이 돈육소시지의 저장성에 미치는 영향을 검토하기 위하여, B 및 I 등급 원료육에 들깻잎을 첨가한 것과 첨가하지 않은 것 4 종류의 돈육소시지를 제조하였다. 돈육소시지의 L＊값은 제조직후가 가장 높았으며, 들깻잎을 첨가한 것이 낮게 나타났다. B 등급 돈육소시지의 a＊값은 저장 8주 째에 가장 낮았고, 들깻잎을 첨가한 B 등급 돈육소시지는 저장 4주 째에 가장 높았으며, E 등급 및 들깻잎을 첨가한 E 등급 돈육소시지는 저장 중 현저한 변화가 없었다. 그리고 들깻잎을 첨가한 것이 첨가하지 않은 것보다 a＊값이 낮았으며, b＊값은 들깻잎을 첨가한 돈육소시지가 높았다. 들깻잎을 첨가한 돈육소시지의 아질산 잔류량은 저장 2주까지 큰 폭으로 감소하였으나, 첨가하지 않은 것은 4주까지 큰 폭으로 감소하여서 들깻잎의 첨가가 아질산 잔류량의 감소에 영향을 미쳤다. B 등급 및 들깻잎을 첨가한 B 등급 돈육소시지의 pH는 4주까지 감소하다가 6주부터 증가하였다. VNN 함량은 저장초기 6.7~8.4mg%이던 것이 저장 중 증가하여 8주 째에는 16.1~19.5mg%를 나타내었다. 돈육소시지의 TBARS는 저장 중 증가하였으며, 들깻잎을 첨가한 것이 첨가하지 않은 것보다 저장 중 더 낮았다. 총균수는 모든 돈육소시지가 저장기간에 따라 증가하였으며, 증가폭은 들깻잎을 첨가한 것이 낮았다.