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141.
Nanostructured nickel hydroxide thin films are synthesized via a simple chemical bath deposition (CBD) method using nickel nitrate Ni(NO3)2 as the starting material. The deposition process is based on the thermal decomposition of ammonia-complexed nickel ions at 333 K. The structural, surface morphological, optical, electrical and electrochemical properties of the films are examined. The nanocrystalline “β” phase of Ni(OH)2 is confirmed by the X-ray diffraction analysis. Scanning electron microscopy reveals a macroporous and interconnected honeycomb-like morphology. Optical absorption studies show that “β-Ni(OH)2” has a wide optical band-gap of 3.95 eV. The negative temperature coefficient of the electrical resistance of “β-Ni(OH)2”, is attributed to the semiconducting nature of the material. The electrochemical properties of “β-Ni(OH)2” in KOH electrolyte are examined by cyclic voltammetric (CV) measurements. The scan-rate dependent voltammograms demonstrate pseudocapacitive behaviour when “β-Ni(OH)2” is employed as a working electrode in a three-electrode electrochemical cell containing 2 M KOH electrolyte with a platinum counter electrode and a saturated calomel reference electrodes. A specific capacitance of ∼398 × 103 F kg−1 is obtained. 相似文献
142.
Ha-Nul Lee Joo-Hee Choi Ji-Yeon Park Jae-Hun Ahn Da Eun Jang Jae Gun Shim Jong-Hwan Park Young-Min Kim 《Food science and biotechnology》2021,30(4):583
Vegetable soup (VS), a plant-based functional food, has been used as a traditional folk medicine and is attracting attention for its ability to enhance the immune response. β-Glucan, a well-established and effective immunomodulator, has synergistic effects when used in combination with some bioactive compounds. In the present study, we aimed to evaluate the synergistic immunomodulatory effects of the combination of VS and β-glucan on macrophage-mediated immune responses. β-Glucan was demonstrated to synergistically enhance the VS-stimulated immune response, including the production of interleukin-6, tumor necrosis factor-α, and nitric oxide, mainly through the mitogen-activated protein kinase pathway in macrophages. In addition, this combination has the potential for further development in functional foods with immune-enhancing activity.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10068-021-00888-x. 相似文献
143.
144.
Pramodkumar D. Jadhav Yang Zuo Youn Young Shim Jianheng Shen Martin J. T. Reaney Ning Zhang Yong Wang 《International Journal of Food Science & Technology》2018,53(8):1972-1982
Linusorbs (LOs; a.k.a. cyclolinopeptides) are naturally occurring orbitides derived from flaxseed. These compounds consist of 8–10 amino acid residues, which are linked via an N ‐ to C‐terminal peptide bond with molecular masses of approximately 1 kDa. The LO circular structure makes them candidates for metal binding studies. Flaxseed extracts are known to suppress Pb and Cd toxicity. Hence, four metal salts surveyed include Zn(CH3COO)2, ZnSO4, Pb(CH3COO)2 and Cd(NO3)2 with pure LOs 1–5 . Proton NMR spectra indicated interaction of LOs with metal salts in solution and were used to determine impacts of methionine oxidation on interactions with metal ions. The methyl group of methionine S,S ‐ dioxide of related LOs did not show the same shift in the presence of Zn(CH3COO)2 and Pb(CH3COO)2 observed in their methionine S ‐ oxide analogues. Metal complexes were observed forming at 10?2 m to 10?4 m but not at lower concentrations (10?5 m to 10?8 m ). Mass spectrometry data confirmed that metal binding strength varied by metal in the order Zn(CH3COO)2<Pb(CH3COO)2<ZnSO4<Cd(NO3)2. 相似文献
145.
Lee Kang Wook Shim Jae Min Kim Dong Wook Yao Zhuang Kim Jeong A. Kim Hyun-Jin Kim Jeong Hwan 《Food science and biotechnology》2018,27(2):489-498
Food Science and Biotechnology - Kimchi was prepared with different types of salts: purified salt (PS), solar salt aged for 1 year (SS1), aged for 3 years (SS3), and bamboo salt... 相似文献
146.
Dae-Woon Jeong Hyun-Suk Na Jae-Oh Shim Won-Jun Jang Hyun-Seog Roh Un Ho Jung Wang Lai Yoon 《International Journal of Hydrogen Energy》2014
Low temperature water–gas shift (WGS) reaction has been carried out at the gas hourly space velocity of 72,152 h−1 over Cu–CeO2 catalyst prepared by a co-precipitation method. Cu loading was optimized to obtain highly active co-precipitated Cu–CeO2 catalysts for low temperature WGS. 80 wt% Cu–CeO2 exhibited the highest CO conversion as well as the most stable activity (XCO > 46% at 240 °C for 100 h). The excellent catalytic performance is mainly due to a strong metal to support interaction, resulting in the prevention of Cu sintering. 相似文献
147.
Won-Seok Ko Ju-Young Oh Jae-Hyeok Shim Jin-Yoo Suh Woo Young Yoon Byeong-Joo Lee 《International Journal of Hydrogen Energy》2014
Inter-diffusion between vanadium and palladium coating layers in vanadium-based hydrogen separation membranes is investigated by using a computational approach based on first-principles calculations and semi-empirical atomistic simulations, paying attention to the surface stability and the prevention of the degradation of hydrogen permeability. It is found that the governing mechanism of the inter-diffusion is the grain boundary diffusion, and therefore a diffusion barrier based on the grain boundary segregation of impurities can be an efficient way to inhibit the inter-diffusion that causes the degradation. An interesting aspect in previous experimental works that showed a good resistance to the inter-diffusion by an addition of a trace amount of yttrium is discussed from the view point of the grain boundary segregation. An experiment that proves the validity of the present alloy design scheme (inhibition of inter-diffusion using grain boundary segregation) is carried out, and a process to maximize the sustainability of the membrane is also proposed. 相似文献
148.
Epigenetic alteration of the donor cells does not recapitulate the reprogramming of DNA methylation in cloned embryos 总被引:3,自引:0,他引:3
Epigenetic reprogramming is a prerequisite process during mammalian development that is aberrant in cloned embryos. However, mechanisms that evolve abnormal epigenetic reprogramming during preimplantation development are unclear. To trace the molecular event of an epigenetic mark such as DNA methylation, bovine fibroblasts were epigeneticallyaltered by treatment with trichostatin A (TSA) and then individually transferred into enucleated bovine oocytes. In the TSA-treated cells, expression levels of histone deacetylases and DNA methyltransferases were reduced, but the expression level of histone acetyltransferases such as Tip60 and histone acetyltransferase 1 (HAT1) did not change compared with normal cells. DNA methylation levels of non-treated (normal) and TSA-treated cells were 64.0 and 48.9% in the satellite I sequence (P < 0.05) respectively, and 71.6 and 61.9% in the alpha-satellite sequence respectively. DNA methylation levels of nuclear transfer (NT) and TSA-NT blastocysts in the satellite I sequence were 67.2 and 42.2% (P < 0.05) respectively, which was approximately similar to those of normal and TSA-treated cells. In the alpha-satellite sequence, NT and TSA-NT embryos were substantially demethylated at the blastocyst stage as IVF-derived embryos were demethylated. The in vitro developmental rate (46.6%) of TSA-NT embryos that were individually transferred with TSA-treated cells was higher than that (31.7%) of NT embryos with non-treated cells (P < 0.05). Our findings suggest that the chromatin of a donor cell is unyielding to the reprogramming of DNA methylation during preimplantation development, and that alteration of the epigenetic state of donor cells may improve in vitro developmental competence of cloned embryos. 相似文献
149.
Se-Ri Kim Yohan Yoon Min-Kyoung Seo Won-Il Kim Won-Bo Shim Duck Hwa Chung Jong Chul Yun Kyoung Yul Ryu Byung-Seok Kim 《Food science and biotechnology》2014,23(4):1349-1356
To establish the best detection method for Escherichia coli O157:H7 on produce, the sensitivity, specificity, and recovery values of 3 selective media [sorbitol MacConkey agar containing cefixime and tellurite (CTSMAC), sorbitol MacConkey agar containing cefixime, tellurite, and 5-bromo-4-chloro-3-indoxyl-β-glucuronide (CTB-SMAC), and CHROMagar O157 were compared. Sample preparation methods (pummeling, sonication, and hand-shaking) were compared to determine the optimum procedure for qualitative analysis from cherry tomato. The selectivity and recovery rates of stressed cell of the 3 tested media were in the order of CHROMagar O157>CTBSMAC>CT-SMAC. The recovery rates of hand-shaken tomatoes (10/10) were higher than rates of sonicated (8/10) and pummeled tomatoes (6/10) for inoculated cherry tomatoes in modified E. coli (mEC) broth enriched with novobicin. CHROMagar O157 was the optimum agar medium for detection of E. coli O157:H7. Cherry tomatoes should be treated with hand-shaking to enhance recovery for qualitative analysis. 相似文献
150.
Effects of Different Salt Treatments on the Fermentation Metabolites and Bacterial Profiles of Kimchi 下载免费PDF全文
Dong Wook Kim Bo‐Min Kim Hyeon‐Jeong Lee Gwang‐Ju Jang Seong Hwa Song Jae‐In Lee Sang Bong Lee Jae Min Shim Kang Wook Lee Jeong Hwan Kim Kyung‐Sik Ham Feng Chen Hyun‐Jin Kim 《Journal of food science》2017,82(5):1124-1131
The effects of purified salt (PS) and mineral‐rich sea salt (MRS), both with different mineral profiles, on kimchi fermentation were studied using a culture‐dependent 16S rRNA sequencing technique and mass‐based metabolomic analysis. The different mineral profiles in the fermentation medium caused changes in the bacterial profiles of the 2 kimchi products. An increase of Leuconostoc species in MRS‐kimchi decreased the Lactobacillus/Leuconostoc ratio, which led to changes in metabolites (including sugars, amino acids, organic acids, lipids, sulfur compounds, and terpenoids) associated with kimchi quality. Although further studies on the relationship between these salt types and kimchi fermentation are needed, these results suggested that the MRS treatment had positively affected the changes of the kimchi mineral contents, bacterial growth, and metabolite profiles, which are linked to kimchi quality. 相似文献