• Journal of Applied Biological Chemistry
• /
• 제61권4호
• /
• pp.383-389
• /
• 2018

Degradation of the insecticide O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate (chlorpyrifos) in aqueous solution was investigated using iron salts and potassium persulfate during ZVI treatment through a series of batch experiments. The degradation rate of chlorpyrifos increased with increases in the concentrations of iron salts and potassium persulfate in the aqueous system. Ferric chloride was found to be the most effective iron salt for the ZVI-mediated degradation of chlorpyrifos in aqueous solution. Further, the iron salts tested could be arranged in the following order in terms of their effectiveness: $FeCl_3$> $Fe_2(SO_4)_3$> $Fe(NO_3)_3$. The persulfate-ZVI system could significantly degrade chlorpyrifos present in the aqueous medium. This revealed that chlorpyrifos degradation by treatment with $Fe^0$ was promoted on adding ferric chloride and potassium persulfate. The kinetics of the degradation of chlorpyrifos by persulfate-amended $Fe^0$ was higher than that for iron-salt-amended $Fe^0$. This suggests that using a sequential $Fe^0$ reduction-ferric chloride or $Fe^0$ reduction-persulfate process may be an effective strategy to enhance the removal of chlorpyrifos in contaminated water.

• Journal of Ecology and Environment
• /
• 제39권1호
• /
• pp.81-90
• /
• 2016

This study was to investigate the effect of salt stress on physiological characteristics such as plant growth, photosynthesis, solutes related to osmoregulation of Beta vulgaris. A significant increase of dry weight was observed in 50 mM and 100 mM NaCl. The contents of Chl a, b and carotenoid were lower in NaCl treatments than the control. On 14 day after NaCl treatment, photosynthetic rate (P_N), the transpiration rate (E) and stomatal conductance of CO₂ (g_s) were reduced by NaCl treatment. On 28 day after NaCl treatment, the significant reduction in g_s and E was shown in NaCl 200 mM. However, P_N and water use efficiency (WUE) in all NaCl treatments showed higher value than that of control. Total ion contents (TIC) and osmolality were higher than the control. On 14 day after treatment, the contents of proline (Pro) increased significantly in 200 mM and 300 mM NaCl concentration compared with control, whereas on 28 day in all treatments it was lower than that of the control. The contents of glycine betaine (GB) increased with the increase of NaCl concentration. The contents of Na⁺, Cl^-, GB, osmolality and TIC increased with the increase of NaCl concentrations. These results suggested that under severe NaCl stress conditions, NaCl treatment did not induce photochemical inhibition on fluorescence in the leaves of B. vulgaris, but the reduction of chlorophyll contents was related in a decrease in leaf production. Furthermore, increased GB as well as Na⁺ and Cl^- contents resulted in a increase of osmolality, which can help to overcome NaCl stress.

• Journal of Microbiology and Biotechnology
• /
• 제30권5호
• /
• pp.726-732
• /
• 2020

Indonesian kefir grains are potential sources of lactic acid bacteria (LAB) that may act as probiotics with specific functional properties. In this study we explored the potential of the probiotic and cholesterol-lowering effect of LAB isolated from Indonesian kefir grains obtained from Bogor, Bandung, Jakarta, and Yogyakarta. The results revealed that 10 isolates showed considerable survivability at low pH and bile salt with total cell reduction of ~3 log colony-forming units per milliliter after exposure to pH 2.5 and 0.5% (w/v) bile salt for 1 and 3 h, respectively. All strains exhibited strong antimicrobial activities against pathogenic bacteria and were sensitive to a wide spectrum of antibiotics but exhibited weak bile salt hydrolase activity. Identification based on 16S RNA suggested that nine isolates were Lactobacillus kefiri and one was Lactobacillus rhamnosus. The ability of the isolates to reduce cholesterol from the media varied, ranging from 22.08% to 68.75% with the highest reduction shown by L. kefiri JK17. The ability to remove cholesterol from the media decreased greatly in resting and dead cells, ranging from 14.58% to 22.08% in resting cells and from 7.89% to 18.17% in dead cells. It can be concluded that Indonesian kefir grains contain LAB potentially acting as probiotics capable of reducing cholesterol. The cholesterol-lowering effect especially occurs when the cells are metabolically active.

• 한국방사성폐기물학회:학술대회논문집
• /
• 한국방사성폐기물학회 2003년도 가을 학술논문집
• /
• pp.363-367
• /
• 2003

우라늄 산화물의 금속전환을 위해 고온 용융염 중에서 전기화학적 환원공정에 대한 관심이 고조되고 있다. 본 공정은 우라늄 산화물뿐만 아니라 다른 악틴족 원소 산화물 및 일부 희토류원소 산화물 역시 금속으로 환원되는 장점을 가지고 있다. 이러한 금속산화물들은 독창적으로 고안된 일체형 음극 및 불활성 양극을 이용하여 금속으로 환원되며, 음극에서 발생된 산소 이온은 양극으로 전달되어 산화됨으로서 산소기체를 발생시킨다. 용융염 중에서 알칼리 및 알칼리토류 산화물에 대한 전기화학적 거동은 아직 완전히 밝혀지지 않았으며, 후행핵연료주기의 단위공정으로서 개발중에 있다. 사용후핵연료의 열 부하는 주로 세슘 및 스트론슘에 의한 것으로, LiC1 용융염 중에서 세슘, 스트론슘 및 바륨 산화물에 대한 용해 속도 및 환원전위를 고찰하였다.

• Macromolecular Research
• /
• 제15권2호
• /
• pp.167-172
• /
• 2007

The reduction behavior of silver ions to silver nanoparticles is an important topic in polymer/silver salt complex membranes to facilitate olefin transport, as this has a significant effect on the long-term performance stability of the membrane. In this study, the effects ofthe solvent type on the formation of silver nanoparticles, as well as the long-term membrane performance of a solid polymer/silver salt complex membrane were investigated. These effects were assessed for solid complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_4$, using either an ionic liquid (IL), acetonitrile (ACN) or water as the solvent for the membrane preparation. The membrane performance test showed that long-term stability was strongly dependent on the solvent type, which increased in the following order: IL > ACN >> water. The formation of silver nanoparticles was more favorable with the solvent type in the reverse order, as supported by UV-visible spectroscopy. The poor stability of the $(PVP)/AgBF_4$ membrane when water was used as the solvent might have been due to the small amount of water present in the silver-polymer complex membranes actively participating in the reduction reaction of the silver ions into silver nanoparticles. Conversely, the higher stability of the $(PVP)/AgBF_4$, membrane when an IL was used as the solvent was attributable to the cooperative coordination of silver ions with the IL, as well as with the polymer matrix, as confirmed by FTIR spectroscopy.

• 대한화학회지
• /
• 제61권5호
• /
• pp.244-250
• /
• 2017

Reduction of (${\pm}$)-3-ketoproline ethyl ester (1) by $NaBH_4$ in the presence of $CaCl_2$ and $MgCl_2$ as the chelating agents gave selective products cis-3(R/S)-alcohols, while reduction by $NaBH_4$ alone or chelated with $NiCl_2$ and $AlBr_3$ gave mixtures of cis- and trans-alcohols. The reduction of (${\pm}$)-1 by various vegetables however, gave exclusively the cis-alcohol as the major and trans-alcohol as the minor. On the contrary, reduction of (${\pm}$)-1 by carrot afforded a mixture of cis- and trans-alcohols, in which the trans-alcohol exists as the major product. In addition, we found that this biocatalyst selectively converted S-enantiomer of (${\pm}$)-1 to the cis-alcohol, and R-enantiomer to a mixture of cis- and trans-alcohols with cis-alcohol as the major product. This fact prompted us to use various fresh plant tissues for stereoselective reduction of diverse types of pyrrolidinones, as its stereoselectivity towards racemic mixtures is higher compared to that using chemical reducing agents.

• 한국응용곤충학회지
• /
• 제15권4호
• /
• pp.185-191
• /
• 1976

맥작에 있어서 문제 광엽잡초를 2,4-D에 의하여 방제하기 위하여 처리약량, 처리시기, 토성별로 실험을 실시하였던 바 그 결과를 요약하면 다음과 같다. 1) 10a 당 $40\%$유제 2,4-D amine salt 70cc를 유효분벽 종지기에 처리하였을 때 보리에 거의 약해를 주지 않고 대부분의 광엽잡초의 방제가 가능하였다. 2) 2,4-D의 최적처리시기는 유효분벽 종지기이며, 이보다도 빠르거나 늦게 될 때에는 약해를 내어 수량감소를 가져왔다. 3) 보리의 내성이 가장 강한 시기에 최적약량처리가 될 때에는 토성에 환계없이 2,4-D의 적용이 가능함을 시사하였다.

• 한국축산식품학회지
• /
• 제38권2호
• /
• pp.417-430
• /
• 2018

This study was conducted to determine the effects of NaCl concentration and cooking temperature on the color and pigment characteristics of presalted ground chicken breasts. Four treatments with different salt concentrations (0%, 1%, 2%, and 3%) were prepared and stored for 7 d prior to cooking. Each sample was cooked to four endpoint temperatures ($70^{\circ}C$, $75^{\circ}C$, $80^{\circ}C$, and $85^{\circ}C$). The salt concentration affected the color and pigment properties of the cooked ground chicken breasts. As the salt concentration increased, the cooking yield and residual nitrite content also increased. However, the samples with 1%, 2%, and 3% NaCl showed similar nitrosyl hemochrome and total pigment contents. Among the products containing salt, the samples with 3% NaCl showed the lowest percentage myoglobin denaturation (PMD) and the lowest CIE $a^*$ values. The cooking temperature had limited effects on the pigment properties of cooked ground chicken breasts. The oxidation-reduction potential and residual nitrite contents increased with cooking temperature, while the PMD, nitrosyl hemochrome, total pigment contents and CIE $a^*$ values were similar in the samples cooked at different temperatures. These results indicated that the addition of up to 2% salt to ground chicken breasts and storage for 7 d could cause the pink color defect of cooked products. However, the addition of 3% NaCl could reduce the redness of the cooked products.

• 한국식생활문화학회지
• /
• 제32권3호
• /
• pp.258-265
• /
• 2017

Although excessive intake of sodium is known to cause various diseases and threaten public health and policies for reducing overconsumption of sodium are being implemented, the theoretical research on sodium intake is incomplete. This study attempted to provide a policy basis by examining whether or not planned behavior theory, which is a typical health communication theory used to describe health-related behaviors, can be applied to explain sodium intake behavior. Especially, sodium ingestion behaviors were compared using the theory of actions planned for men and women as well as young people, middle-aged, and elderly persons, who are predicted to show differences in eating habits. In this study, questionnaires were prepared to measure the daily eating habits of subjects and subordinate factors of planned behavior theory: behavioral beliefs, outcome expectations, normative beliefs, compliance motivation, and control beliefs. Questionnaires were given to 93 college students and their families. As a result of the difference analysis and path analysis of the questionnaire responses, the following suggestions were obtained. First, age difference is more obvious than sex difference in terms of low salt intentions. For example, older people are healthier than younger people in terms of eating habits and health concerns. Second, the elderly are more likely to practice the low-salt formula when they are provided information on the benefits and effects of the low-salt formula compared to younger ones. Third, systematic efforts are needed to promote a culture that emphasizes the health benefits of a low salt diet rather than providing piecemeal information on the advantages and effects of a low salt diet.

• 한국재료학회지
• /
• 제14권11호
• /
• pp.813-820
• /
• 2004

The electrolytic reduction of spent oxide fuel involves the liberation of oxygen in a molten LiCl electrolyte, which is a chemically aggressive environment that is very corrosive for typical structural materials. So, it is essential to choose the optimum material for the process equipment handling molten salt. In this study, corrosion behavior of Haynes 263, 75, and Inconel X-750, 718 in molten salt of $LiCl-Li_{2}O$ under oxidation atmosphere was investigated at $650^{\circ}C\;for\;72\sim360$ hours. At $3\;wt\%\;of\;Li_{2}O$, Haynes 263 alloy showed the highest corrosion resistance among the examined alloys, and up to $8\;wt\%\;of\;Li_{2}O$, Haynes 75 exhibited the highest corrosion resistance. Corrosion products were formed $Li(Ni,Co)O_2,\;LiNiO_2\;and\;LiTiO_2\;and\;Cr_{2}O_3$ on Haynes 263, $Cr_{2}O_3,\;NiFe_{2}O_4,\;LiNiO_2,\;Li_{2}NiFe_{2}O_4,\;Li_{2}Ni_{8}O_10$ and Ni on Haynes 75, $Cr_{2}O_3,\;(Al,Nb,Ti)O_2,\;NiFe_{2}O_4,\;and\;Li_{2}NiFe_{2}O_4$ on Inconel X-750 and $Cr_{2}O_3,\;NiFe_{2}O_4\;and\;CrNbO_4$ on Inconel 718, respectively. Haynes 263 showed local corrosion behavior and Haynes 75, Inconel X-750, 718 showed uniform corrosion behavior.