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961.
962.
Jung-Ah Shin Sang-Hwa Jeong Cai-Hua Jia Ki-Teak Lee 《Food science and biotechnology》2018,27(4):1041-1046
Decarboxylation of ferulic acid would increase the solubility in oils. Rice bran extract (RBE) containing 29 mg ferulic acid/g RBE was decarboxylated to obtain decarboxylated rice bran extract (DRBE), and its antioxidant capacity in oil system was studied. After addition of DRBE (500 ppm), oxidation was monitored for 20 days at 60 °C under the dark. To compare the oxidation degree, 500 ppm of ferulic acid and well-known lipid soluble antioxidant, α-tocopherol, were used. Contents of conjugated dienes and aldehydes were measured using 1H NMR as well as peroxide value (POV). On 7 days of oxidation, DRBE (539.0 meq/kg oil) showed lower POV than the control (819.7 meq/kg oil). Also, contents of total conjugated form and aldehydes were 194.60, and 5.94 mmol/L oil, which were lower than those of control (323.63 and 15.94 mmol/L oil). However, after 10 days of oxidation, antioxidant capacity of DRBE was not observed. 相似文献
963.
Eun Joo Shin 《纺织学会志》2018,109(2):241-247
Poly(ethylene-3,4-dioxythiophene)/poly(styrene sulfonic acid)(PEDOT/PSS) water dispersions are commercially available, and various coating formulations for substrates, such as glass, plastics, and ceramics, have been suggested. Recently, it was found that the addition of a small amount of organic solvent, such as ethylene glycol (EG) and dimethylsulfoxide (DMSO), to the aqueous dispersion of PEDOT/PSS increases the conductivity significantly. This study examined how a combination of solvent addition affects the PEDOT/PSS conductivity of artificial leather (napping fabric with short fur). In addition, the sustainability of the PEDOT/PSS conductivity for the common use of artificial leather was investigated using abrasion and tension cycle tests. The electric conductivity of the leather increased in the order of EG < DMSO < EG + DMSO. The sustainability of the PEDOT/PSS conductivity in the case of EG + DMSO was superior to that of the EG or DMSO solvents. The padding process was found to be a more effective method for achieving durability against abrasion and tension cycle with a lower deposit weight than when using the coating process. The mechanical properties of the synthetic leather using the padding process also showed high performance compared to the coating process. 相似文献
964.
Choi Seung Hak Lee Ah Young Park Chan Hum Shin Yu Su Cho Eun Ju 《Food science and biotechnology》2018,27(5):1475-1484
Food Science and Biotechnology - Chronic alcohol consumption induces damage to the brain that can cause various forms of dementia. An abundance of acetaldehyde is produced by excessive alcohol... 相似文献
965.
Highly active and stable hydrogen production at high current densities is required for practical application of electrocatalytic water splitting. In this study, highly active self-supporting electrodes with excellent durability were designed and developed for high-performance overall water splitting at a high current density. First, a colloid-based dip-coating method using porous carbon cloth (PCC) was introduced to obtain uniformly coated Ni and Fe nanoparticles on a conductive substrate. Then, the desired phase transitions of Ni and Fe to Ni2P and FeP, respectively, proceeded by thermal phosphidation at optimum temperature. The uniformly interconnected Ni2P layers on the PCC substrate (Ni2P@PCC) and FeP layers on the PCC substrate (FeP@PCC) exhibited outstanding oxygen and hydrogen evolution reactions, respectively. When each electrode was adopted as an anode and a cathode for the overall water splitting cell, excellent performance was achieved, with a low operational voltage of 1.76 V and high durability for 100 hours at a high current density of 50 mA cm−2. 相似文献
966.
Food Science and Biotechnology - In this study, a headspace gas chromatography (HS-GC) method was carried out to determine the contents of acetaldehyde, methanol and fusel oils in distilled liquors... 相似文献
967.
968.
Sang Mi Lee Jieun Oh Byung‐Serk Hurh Gwi‐Hwa Jeong Young‐Keum Shin Young‐Suk Kim 《Journal of food science》2016,81(12):C2915-C2922
This study investigated the profiles of volatile compounds produced by Lactobacillus paracasei during oat fermentation using gas chromatography‐mass spectrometry coupled with headspace solid‐phase microextraction method. A total of 60 compounds, including acids, alcohols, aldehydes, esters, furan derivatives, hydrocarbons, ketones, sulfur‐containing compounds, terpenes, and other compounds, were identified in fermented oat. Lipid oxidation products such as 2‐pentylfuran, 1‐octen‐3‐ol, hexanal, and nonanal were found to be the main contributors to oat samples fermented by L. paracasei with the level of 2‐pentylfuran being the highest. In addition, the contents of ketones, alcohols, acids, and furan derivatives in the oat samples consistently increased with the fermentation time. On the other hand, the contents of degradation products of amino acids, such as 3‐methylbutanal, benzaldehyde, acetophenone, dimethyl sulfide, and dimethyl disulfide, decreased in oat samples during fermentation. Principal component analysis (PCA) was applied to discriminate the fermented oat samples according to different fermentation times. The fermented oats were clearly differentiated on PCA plots. The initial fermentation stage was mainly affected by aldehydes, whereas the later samples of fermented oats were strongly associated with acids, alcohols, furan derivatives, and ketones. The application of PCA to data of the volatile profiles revealed that the oat samples fermented by L. paracasei could be distinguished according to fermentation time. 相似文献
969.
Simultaneous determination of water‐soluble whitening ingredients and adenosine in different cosmetic formulations by high‐performance liquid chromatography coupled with photodiode array detection 下载免费PDF全文
970.
Miyoung Yoo Sanghee Lee Sunyoung Kim Su‐ji Kim Hye‐young Seo Dongbin Shin 《International Journal of Food Science & Technology》2014,49(6):1480-1489
This study was performed to establish a rapid analytical method to determine the presence of fourteen polycyclic aromatic hydrocarbons (PAHs) in seafoods by high‐performance liquid chromatography with fluorescence detection (HPLC/FLD). The samples were prepared using two methods: the Quick, Easy, Cheap, Effective, Rugged, Safe (QuEChERS) method and the alkali digestion method. The QuEChERS method involved a convenient and effective solid–liquid extraction and a simple purification. The alkali digestion method was comprised of a liquid–liquid extraction after saponification with potassium hydroxide followed by purification. The limits of detection (LODs) and limits of quantification (LOQs) of the QuEChERS method ranged from 0.05 to 1.60 μg kg?1, and those of the alkali digestion method ranged from 0.28 to 5.18 μg kg?1. The repeatability for all target analytes was similar for the two methods, that is, 0.66–4.24% and 0.26–5.75% for the QuEChERS and alkali digestion methods, respectively. At analyte concentrations of 2.5–50 μg kg?1, the recovery of the QuEChERS method ranged from 86.87% to 115.67% and that of the alkali digestion method ranged from 69.22% to 100.21%. 相似文献