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Jang Junhyuk Kim Tack-Jin Eun Hee-Chul Kim Gha-Young Lee Sungjai 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):649-654
Journal of Radioanalytical and Nuclear Chemistry - U recovery test was performed on a Zn-U alloy to confirm the feasibility of Zn as an alternative cathode material. An evaporation test of pure Zn... 相似文献
73.
Dr. Wonhee Lee Young Eun Kim Dr. Min Hye Youn Dr. Soon Kwan Jeong Dr. Ki Tae Park 《Angewandte Chemie (International ed. in English)》2018,57(23):6883-6887
Electrochemical reduction of carbon dioxide (CO2) into value‐added chemicals is a promising strategy to reduce CO2 emission and mitigate climate change. One of the most serious problems in electrocatalytic CO2 reduction (CO2R) is the low solubility of CO2 in an aqueous electrolyte, which significantly limits the cathodic reaction rate. This paper proposes a facile method of catholyte‐free electrocatalytic CO2 reduction to avoid the solubility limitation using commercial tin nanoparticles as a cathode catalyst. Interestingly, as the reaction temperature rises from 303 K to 363 K, the partial current density (PCD) of formate improves more than two times with 52.9 mA cm?2, despite the decrease in CO2 solubility. Furthermore, a significantly high formate concentration of 41.5 g L?1 is obtained as a one‐path product at 343 K with high PCD (51.7 mA cm?2) and high Faradaic efficiency (93.3 %) via continuous operation in a full flow cell at a low cell voltage of 2.2 V. 相似文献
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A simple, rapid and accurate method for the spectrophotometric determination of chloride in non-polar media is described. The method is based on the well-known reaction of mercury(II) thiocyanate with chloride to release thiocyanate, which then reacts with iron(III). The optimum concentrations of reagents for the determination of chloride in 2,2,4-trimethylpentane (iso-octane) and cyclohexane are reported. The molar absorptivity of the complex at 505 nm is 5120 ± 200 dm3 mol?1 cm?1 for iso-octane and 5340 ± 340 dm3 mol?1 cm?1 for cyclohexane. Beer's Law is obeyed in the range 2 × 10?7–2 × 10?5 mol dm?3 (0.01–1 mg l?1) chloride. 相似文献
76.
Jeong Young Eun Kumar Pullur Anil Ha Heon Phil Lee Kwan-young 《Research on Chemical Intermediates》2018,44(11):6803-6829
Research on Chemical Intermediates - Herein, we investigated the NOx reduction performance of Sb–V–CeO2/TiO2 (SbVCT) catalyst subjected to hydrothermal aging, where 6 vol% of H2O was... 相似文献
77.
Se Hoon Ki Somin Sin Jae-Ho Shin Young Wan Kwon Myoung Won Chae Han Sup Uhm Ku Youn Baik Eun Ha Choi 《Plasma Chemistry and Plasma Processing》2018,38(5):937-952
The studies with proteins are necessary to understand the biological effects of atmospheric pressure plasma (APP). Among proteins, those with transient metal ions play key roles in many biological events and they are very sensitive to environmental redox states. Iron-containing hemoglobin (Hb) is investigated in this study, after APP treatments under two environmental gas conditions of pure N2 and N2?+?O2 mixture. Monitoring the intensity change for absorption spectra could lead to a quantitative assessment of the effect of discharge plasma on Hb. Redox states of Hb are classified into five states including O2-bound Hb (oxy-Hb), deoxy-Hb, met-Hb, NO-bound Hb (NO-Hb), and hemichrome. Chemically generated reactive species and some scavengers are applied to understand the chemical reactions. Our experimental results confirm the complex chemical reactions of APP and suggest the possible use of Hb as a model protein for the visualization of APP biological effects. 相似文献
78.
Yoo NY Youn YS Oh NM Oh KT Lee DK Cha KH Oh YT Lee ES 《Colloids and surfaces. B, Biointerfaces》2011,88(1):419-424
The purpose of this study was to fabricate porous poly(lactide-co-glycolide) (PLGA) microparticles for efficient pulmonary deposition and increased therapeutic duration of the antioxidant anthocyanin (ATH). These microparticles were prepared by a water-in-oil-in-water (W(1)/O/W(2)) multi-emulsion method with vaporizing ammonium bicarbonate (AB) as a porogen and starch as a viscous additive. High porosity achieved by the decomposition reaction of AB to the base of ammonia, carbon dioxide, and water vapor at 50°C enabled efficient deposition of ATH throughout the entire lung in BALB/c mice. In addition, the porous microparticles incorporating starch showed sustained ATH release characteristics (up to 5 days) and protracted antioxidant activity (up to 5 days) for 2,2-diphenyl-1-pikryl-hydrazyl (DPPH) radicals, which was comparable to that of the porous microparticles without starch which completely released ATH in 2h. Furthermore, these porous microparticles incorporating starch led to longer ATH residence (up to 20 days) in in vivo lung epithelium. We believe that this system has great pharmaceutical potential as a long-acting antioxidant for continuously relieving oxidative stress in pulmonary diseases like chronic obstructive pulmonary disease (COPD). 相似文献
79.
When used as solvent, chloroform was found to act as a hydrogen atom donor in Barton reductive decarboxylation reactions. Chloroform offers a substantial practical advantage over pre-existing hydrogen atom donors. 相似文献
80.