• 한국표면공학회지
• /
• 제51권1호
• /
• pp.62-70
• /
• 2018

Sulfamate plating solution containing a small amount of chloride bath was fabricated to study the properties of the electrodeposited Ni thin films. Effects of the changes of current density and additive concentration on current efficiency, residual stress, surface morphology and microstructure of Ni thin films electrodeposited from Ni sulfamate-chloride baths were investigated. The current efficiency was measured to be more than about 95%, independent of the changes of current density and saccharin concentration in the baths. Residual stress of Ni thin film was appeared to be the compressive stress modes in the range of $5{\sim}30mA/cm^2$ current density. Maximum compressive stress was observed at the current density of $10mA/cm^2$. Compressive stress values of Ni thin/thick films were increased to be about -85~-100 MPa with increasing saccharin concentration from 0 to 0.0195 M(4 g/L). Surface morphology was changed from smooth to nodule surface appearance with increasing the current density. Smooth surface morphology of Ni thin films electrodeposited from the baths containing saccharin was observed, independent of the saccharin concentration. Ni thin/thick films consist of FCC(111), FCC(200), FCC(220), FCC(311) and FCC(222) peaks. It was revealed that the FCC(200) peak of Ni thin films is the preferred orientation in the range of $5{\sim}30mA/cm^2$ current density. The intensity of FCC(200) peak was gradually decreased and the intensity of FCC(111) peak was increased with increasing saccharin concentration in the baths.

• KSBB Journal
• /
• 제22권4호
• /
• pp.213-217
• /
• 2007

첨가제가 단백질 약물 방출 속도 및 약물 제제 제조 및 구조에 미치는 영향을 고찰하였다. 친수성 첨가제인 D-sorbitol의 경우 친유성 첨가제보다 단백질 약물 방출 속도를 감소시킬 수 있었으며 최적의 농도는 3% (w/v)로 나타났다. 또한 제제 제조시 점도를 낮게 유지할 뿐 아니라 상분리 없는 균일한 pluronic 용액상태를 유지하여 약물이 첨가될 경우에 균일한 약물제제를 만들 수 있었다. 한편 D-sorbitol은 pluronic 수용액의 CMC를 낮추고 마이셀 표면에 작용하여 구조를 강화하는 역할을 수행하는 것으로 보인다. 따라서 pluronic 제제에 D-sorbitol을 첨가하여 단백질 약물의 안정성을 향상시키고 효과적인 약물전달 시스템을 설계할 수 있었다.

• 한국수소및신에너지학회논문집
• /
• 제24권1호
• /
• pp.1-11
• /
• 2013

Additives such as glycerol, methanol, acetone, and ethanol were used to prevent $NaBO_2$ from precipitation, and their effects on hydrogen generation properties of $NaBH_4$ hydrolysis were investigated. When the concentration of additives was 5 wt%, the additives such as methanol, acetone, and ethanol could not prevent $NaBO_2$ precipitation. Although glycerol prevented $NaBO_2$ precipitation, conversion efficiency decreased to 78.0% due to its viscosity. Based on test results, hydrogen generation tests were also performed at various concentration of glycerol and methanol to investigate the concentration effects on hydrogen generation properties. As the concentration of glycerol increased from 1 wt% to 3 wt%, conversion efficiency increased owing to additive effect. When its concentration increased to 5 wt%, conversion efficiency decreased due to its viscosity. As the concentration of methanol increased from 5 wt% to 10 wt%, conversion efficiency increased owing to additive effect. When its concentration increased to 15 wt%, conversion efficiency decreased due to $NaB(OCH_3)_4$ precipitate. Although conversion efficiency decreased about 1% when 3 wt% glycerol was added, $NaBO_2$ precipitation was prevented. Consequently, addition of 3 wt% glycerol to $NaBH_4$ solution improves stability of hydrogen generation system.

• 한국주조공학회지
• /
• 제37권5호
• /
• pp.148-156
• /
• 2017

The effects of minor additives on the casting properties of AC4A aluminum alloys were investigated. Measurements of the cooling curve and microstructure observations were conducted to analyze the effects of Ti-B and Sr minor elements during the solidification process. A fine grain size and an increase in the crystallization temperature for the ${\alpha}-Al$ solution were evident after the addition of 0.1wt% Al-5%Ti-1%B additive. The modification effect of the eutectic $Mg_2Si$ phase with the addition of 0.05% Al-10%Sr additive was prominent. A fine eutectic $Mg_2Si$ phase and a decrease in the growth temperature of the eutectic $Mg_2Si$ phase were evident. Fluidity, shrinkage and solidification-cracking tests were conducted to evaluate the castability of the alloy. The combined addition of Al-5%Ti-1%B and Al-10%Sr additives showed the maximum filling length owing to the effect of the fine ${\alpha}-Al$ grains. The macro-shrinkage ratio increased, while the micro-shrinkage ratio decreased with the combined addition of Al-5%Ti-1%B and Al-10%Sr additives. The macro-shrinkage ratio was nearly identical, while the micro-shrinkage ratio increased with the addition of the Al-10%Sr additive. The tendency of the occurrence of solidification cracking decreased owing to the effect of the fine ${\alpha}-Al$ grains and the modification of the $Mg_2Si$ phase with the combined addition of Al-5%Ti-1%B and Al-10%Sr additives.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제9권2호
• /
• pp.279-281
• /
• 2004

Components of genetic variation were estimated for five metric traits using 24 biparental progenies (N. C. Design III) generated from F$_2$ generation of a commercial bivoltine silkworm hybrid, SH$_{6}$${\times}$NB$_4$D$_2$. Variance due to additive ($\sigma$$^2$A) and dominance ($\sigma$$^2$D) gene effects was significant for single cocoon weight and shell weight. However, magnitude of former was greater than latter indicating preponderance of additive gene action in the inheritance of these two traits. Average degree of dominance was in the range of partial dominance for all the traits. High estimates of heritability (ns) indicated operation of genes with large additive effects, hence, scope exists for improvement of present populations through a few cycles of selection.n.

• 한국식품위생안전성학회지
• /
• 제21권4호
• /
• pp.258-262
• /
• 2006

환경호르몬 물질의 생체내에서의 상호작용에 의한 상자 또는 상승 작용을 알아보기 위하여 환경호르몬 물질들을 조합하여 마우스에 처치한 후 생체내에서 생식기의 변화 정도를 조직병리학적으로 관찰하였다. 암컷 ICR마우스에 난소적출술을 실시하고 2주 후에 DEHP, DBP, BPA의 환경호르몬 물질을 단독 또는 두개씩 조합하여 마우스에 피하로 주입하였다. 육안적인 변화에서는 모든 군에서 이상이 관찰 되지 않았으며, 부검 후 자궁의 무게를 측정한 결과에 있어서도 유의적인 변화를 관찰할 수 없었으나, 자궁 내 fluid존재에 있어서는 E2 단독 투여 군과 E2와 함께 투여한 모든 그룹(E2+DEHP, E2+DBP, E2+BPA)에서 관찰되었다. 조직병리학적인 관찰에 있어서는.자궁상피세포, 질 상피세포, 유선의 변화 그리고 난관 직경의 변화를 관찰하였다. 그 결과 민감도에 있어서 가장 유의적인 변화를 보인 항목은 질 상피세포의 변화였으며, 환경호르몬 물질을 두개씩 혼합하여 처치한 그룹에 있어 단독으로 처치한 그룹과 비교 시 변화의 정도가 심한 것이 일부 관찰 되었으나 통계학적으로 유의성을 가지고 있다고 결론을 내리기 는 힘들었다. 결론적으로 환경호르몬물질간의 생체내에서 상가 혹은 상승작용에 대한 명확한 결과는 도출할 수 없었으나, 환경호르몬물질이 생체내 작용하는 데에 있어서 서로 간에 상승작용을 할 수 있다는 가능성은 충분한 것으로 판단되어진다.

• 한국작물학회지
• /
• 제35권1호
• /
• pp.58-64
• /
• 1990

최근 국내에서 연구가 시작되고 있는 신규 식물생장조정제인 brassinolide류와 기존의 auxin류를 혼용하였을 경우 상호작용성을 구명하여 농업적 이용의 기초자료를 얻고자 몇가지 생물검정법을 이용하여 상호작용의 결과를 분석해 본 결과를 요약하면 다음과 간다. 1. 벼 엽신기부굴절검정에서는 두 화합물의 저농도 혼용조합에서 길항적인 반응을 보였으나, 대부분의 조합에서는 상가 또는 상승작용을 하였으며, 고농도의 혼용일수록 상승효과가 높았고, IAA가 2, 4-D에 비해 다소 혼용효과가 높았다. 2. 귀리 자엽소신장검정에서는 HBR의 농도에 관계없이 IAA 0.1ppm 이하에서는 상승작용을 하였으나 0.3ppm 이상의 혼용에서는 상가적인 반응을 나타내었다. 3. 무 하배축신장검정에서는 자엽의 유무에 의해 반응이 다르게 나타났는데, 자엽을 제거한 절편에서는 IAA 3ppm과 HBR과의 혼용조합을 제외하고는 대부분의 혼용조합이 길항적인 반응을 보였다. 4. 이상에서와 같이 검정방법간 혼용효과가 뚜렷한 차이가 있었으며, 공시재료에 따라 상호작용의 효과가 다르게 나타났는데 auxin의 함량이 비교적 높은 생장점을 가진 절편에서는 대체로 길항작용을 보인 반면, 선단부를 제거하여 내생호르몬이 불안정한 절편에서는 상가 또는 상승작용을 보였다.

• Animal Bioscience
• /
• 제36권12호
• /
• pp.1785-1795
• /
• 2023

Objective: This study was to estimate heritabilities, additive genetic correlations, and phenotypic correlations between number of piglets born alive (NBA), litter birth weight (LTBW), number of piglets weaned (NPW) and litter weaning weight (LTWW) in different parities of Landrace (L), Yorkshire (Y), Landrace×Yorkshire (LY), and Yorkshire×Landrace (YL) sows in a commercial swine operation in Northern Thailand. Methods: Two models were utilized, a single trait repeatability model (RM) and a multiple trait animal model (MTM). The RM assumed reproductive records from different parities to be repeated values of the same trait, whereas the MTM assumed these records to be different traits. The two models accounted for the fixed effects of farrowing year-season, genetic group of the sow, heterosis, and age at first farrowing, and the random effects of sow, boar, and residual. Results: Heritability estimates from RM were 0.02±0.01 for NBA, 0.10±0.01 for LTBW, 0.04±0.01 for NPW, and 0.11±0.01 for LTWW. Heritability estimates from MTM fluctuated across parities, ranging from 0.04±0.01 in parity 2 to 0.09±0.02 in parity 4 for NBA, 0.07±0.02 in parity 2 to 0.16±0.02 in parity 3 for LTBW, 0.04±0.02 in parity 4 to 0.08±0.01 in parity 1 for NPW, and 0.16±0.02 in parity 1 to 0.20±0.02 in parity 2 for LTWW. Additive genetic correlation estimates from MTM were also variable, ranging from 0.29±0.24 between NBA in parity 1 and NBA in parity 2 to 0.99±0.05 between LTWW in parity 3 and LTWW in parity 4. Conclusion: The findings of this study highlight the advantage of using MTM for the genetic improvement of reproductive traits in swine and contribute to the development of sustainable swine breeding programs in Thailand.

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 2002년도 춘계 학술발표강연 및 논문개요집
• /
• pp.41-41
• /
• 2002

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2001년도 춘계학술발표회 초록집
• /
• pp.19-20
• /
• 2001