• Title/Summary/Keyword: additive effects

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Effects of the Changes of Current Density and Additive Concentration on Ni Thin Films in Ni Sulfamate-chloride Electrodeposition Baths (Ni Sulfamate-chloride 전기도금 용액에서 전류밀도와 첨가제의 농도 변화가 Ni 박막에 미치는 영향)

  • Yoon, Pilgeun;Park, Deok-Yong
    • Journal of the Korean institute of surface engineering
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    • v.51 no.1
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    • pp.62-70
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    • 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.

Effects of Hydrophilic Additives on the Release Rate of Protein Drugs (단백질 약물 방출속도에 미치는 친수성 첨가제의 영향)

  • Kwon, Young-Kwan;Kim, Ji-Hyeon;Yoo, Young-Je
    • KSBB Journal
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    • v.22 no.4
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    • pp.213-217
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    • 2007
  • It has been reported that hydrophobic additives generally decrease the release rate of protein drugs from drug delivery systems (DDS) and hydrophilic additives increase the release rate. In many cases, however, the addition of hydrophilic molecule is necessary for improving the stability of protein drugs. In the present work, the effects of hydrophilic additives on the release profiles, and micelle formation of protein drug formulations were investigated to develop a novel method for protein drug delivery. For model protein drug, bovine serum albumin (BSA) was employed and several hydrophilic additives were used in the release experiments. Hydrophilic additive D-sorbitol showed the lower release rates of BSA than other hydrophobic additives due to the gel strengthening ability of the additive and the optimum concentration of D-sorbitol was 3 w/v % for the retarded release rate. In addition, it was found that the addition of D-sorbitol was very effective for obtaining homogeneous and stable DDS. The results were discussed in terms of the micelle formation and the micelle structure, i.e., the differences in gel structure and the distribution of drugs in micelles.

Effect of Additives for Prevention of NaBO2 Precipitation on Hydrogen Generation Properties of NaBH4 Hydrolysis (NaBO2의 석출 방지를 위한 첨가제가 NaBH4 가수분해의 수소발생특성에 미치는 영향)

  • Oh, Taekyun;Kwon, Sejin
    • Transactions of the Korean hydrogen and new energy society
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    • v.24 no.1
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    • pp.1-11
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    • 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.

Effect of Minor Additives on Casting Properties of AC4A Aluminum Casting Alloys (AC4A 알루미늄 합금의 주조특성에 미치는 미량 첨가원소의 영향)

  • Oh, Seung-Hwan;Kim, Heon-Joo
    • Journal of Korea Foundry Society
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    • v.37 no.5
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    • pp.148-156
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    • 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.

Estimation of Genetic Components of Variance in Biparental Progenies of Bivoltine Silkworm (Bombyx mori L.)

  • Malik, Gulam Nabi;Sofi, Abdul Majeed;Haque Rufaie, Syed Zia;Singh, Tejender Paul;Aijaz, Mohammad;Malik, Manzoor Ahmad;Dar, Habib Ullah
    • International Journal of Industrial Entomology and Biomaterials
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    • v.9 no.2
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    • pp.279-281
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    • 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.

Histopathologic Changes to Additive Effect of Endocrine Disruptors in Mice (마우스에서의 환경호르몬물질의 상가작용에 대한 조직학적인 변화)

  • Jung, Ji-Youn
    • Journal of Food Hygiene and Safety
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    • v.21 no.4
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    • pp.258-262
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    • 2006
  • To investigate additive effects of endocrine disruptors, we have histopathologically studied the exchanges of the reproductive organ to ovariectomized ICR mice. Female ICR mice were ovariectomized and then treated with endocrine disruptors after two weeks. Macroscopic exchanges, which were body weight, feed and water intake, of all groups were not seen during experiment period. Histopathological changes of uterine epithelial cells, vaginal epithelial cells, mammary glands and the diameter in uterine tubles were observed. In the results, the histopathological sensitivity to endocrine disruptors effect was more seen to the vaginal epithelial cell height than others. The additive estrogenic effects of endocrine disruptors, which were combinations of DEHP, DBP and BPA, were seen with E2 and BPA treatments. These results offers a sysmatic and mechanistically informative approach to assessing estrogenicity. It provides a useful profile of activity using a reasonable amount of resources and is compatible with the study of individual chemicals as well as the investigation of interactions among combinations of chemicals.

Interaction between Brassinolide and Auxins on Bioassays (Brassinolide와 Auxin과의 상호작용의 생물검정에 의한 평가)

  • Choi, Chung-Don;Kim, Soon-Chul;Lee, Soo-Kwan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.1
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    • pp.58-64
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    • 1990
  • This study was conducted to investigate the interaction effect of a new plant growth regulator brassinolide and auxins using several bioassay methods such as rice lamina inclination test, oat coleoptile segment growth test and radish hypocotyl elongation test. For rice lamina inclination test, the antagonistic response showed at low concentration combinations of homobrassinolide and auxins (IAA and 2,4-D), while the combinations of high concentration responsed mostly synergistic or additive effects, IAA was generally higher than 2,4-D for combination effect with homobrassinolide. For oat coleoptile segment growth test, the synergistic effect showed at IAA concentrations less than 0.1ppm while additive response exhibited above 0.3ppm regardless of homobrassinolide concentrations. In radish hypocotyl elongation test, the interaction response varied with cotyledon. The sections removed cotyledon showed mostly antagonistic effects, except for combination of homobrassinolide with IAA 3ppm. Interaction responses were Quite different from bioassay methods, particularly using experimental materials: antagonistic responses were usually shown at the section that attached growing point while these for sections that removed growing point were responded synergistic or additive effect due to unstable endogenous hormones.

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Estimation of heritabilities and additive genetic correlations for reproduction traits in swine: insights for tropical commercial production systems using multiple trait animal models

  • Udomsak Noppibool;Thanathip Suwanasopee;Mauricio A. Elzo;Skorn Koonawootrittriron
    • Animal Bioscience
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    • v.36 no.12
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    • pp.1785-1795
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    • 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.