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71.
Polyaniline nanocomposites encapsulating gold nanoparticles on camphor sulfonic acid (CSA) surface were prepared via the polymerization of aniline hydrochloride with different concentrations of CSA using HAuCl4 as oxidant. The synthesized composites were characterized by Fourier transform infrared spectroscopy and UV–visible spectroscopy. Surface morphology was studied by scanning electron microscopy and transmission electron microscopy. The embedded crystallinity of the composites was investigated by X‐ray diffraction analysis. The solubility of the nanocomposites was studied using water, N‐methyl‐2‐pyrrolidinone, chloroform, and dimethylformamide solvents. The room temperature direct current conductivity of the composites was also observed in solution state. Electrical property of the composites was examined using cyclic voltammetric measurements at room temperature. The fabricated polymer nanocomposites with better solubility in water and some organic solvents will have various applications in electrical devices and biosensors. POLYM. COMPOS., 36:245–252, 2015. © 2014 Society of Plastics Engineers 相似文献
72.
Sung Ho Oh Jae Gun Han Young Kim Ji Hye Ha Seung Seop Kim Myoung Hoon Jeong Hyang Suk Jeong Na Young Kim Jeong Sub Cho Won Byong Yoon Shin Young Lee Do Hyung Kang Hyeon Yong Lee 《Journal of Bioscience and Bioengineering》2009,108(5):429-434
Autotrophic growth of Porphyridium cruentum under 18:12 h and 12:12 h light:dark cycles showed the maximum cell concentration of 2.1 g-dry wt./L, whereas the specific growth rate, 0.042 (1/h), at 18:6 h is faster than that of 12:12 h, 0.031 (1/h), respectively. The highest lipid accumulation level, 19.3 (%, w/w), was achieved at 12:12 h cycle. Under dark cultivation condition with 10 g/L of glucose, the lipid accumulation in the cell was 10.9 (%, w/w), whereas the heterotrophic growth with glycerol as the carbon resource showed low level of cell concentration and lipid production, compared to that of glucose. The glucose was decided to be a suitable carbon resource for the heterotrophic growth of P. cruentum. The lipids from P. cruentum seemed be feasible for biodiesel production, because over 30% of the lipid was C16–C18:1. The cultivation time and temperature were important factors to increase the maximum cell concentration. Extending the cultivation time helps maintain the maximum cell concentration, and higher lipid accumulation was achieved at 25 °C, compared to 35 °C. The fed-batch cultures showed that, under the light condition, the specific production rate was slightly decreased to 0.4% lipid/g-dry wt./day at the later stage, whereas, under the dark condition, the specific production rate was maintained to be a maximum value of 1.1% lipid/g-dry wt./day, even in the later stage of cultivation. The results indicate that the heterotrophic or 12:12 h cyclic mixotrophic growth of P. cruentum could be used for the production of biodiesel in long-term fed-batch cultivation of P. cruentum. 相似文献
73.
Next‐Generation Sequencing Analyses of Bacterial Community Structures in Soybean Pastes Produced in Northeast China 下载免费PDF全文
Mi‐Hwa Lee Fan‐Zhu Li Jiyeon Lee Jisu Kang Seong‐Il Lim Young‐Do Nam 《Journal of food science》2017,82(4):960-968
Fermented soybean foods contain nutritional components including easily digestible peptides, cholesterol‐free oils, minerals, and vitamins. Various fermented soybean foods have been developed and are consumed as flavoring condiments in Asian regions. While the quality of fermented soybean foods is largely affected by microorganisms that participate in the fermentation process, our knowledge about the microorganisms in soybean pastes manufactured in Northeast China is limited. The current study used a culture‐independent barcoded pyrosequencing method targeting hypervariable V1/V2 regions of the 16S rRNA gene to evaluate Korean doenjang and soybean pastes prepared by the Hun Chinese (SPHC) and Korean minority (SPKM) populations in Northeast China. In total, 63399 high‐quality sequences were derived from 16 soybean paste samples collected in Northeast China. Each bacterial species‐level taxon of SPHC, SPKM, and Korean doenjang was clustered separately. Each paste contained representative bacterial species that could be distinguished from each other: Bacillus subtilis in SPKM, Tetragenococcus halophilus in SPHC, and Enterococcus durans in Korean doenjang. This is the 1st massive sequencing‐based study analyzing microbial communities in soybean pastes manufactured in Northeast China, compared to Korean doenjang. Our results clearly showed that each soybean paste contained unique microbial communities that varied depending on the manufacturing process and location. 相似文献
74.
75.
A mixed culture of dye-decolorising Pseudomonas spp. was immobilised on polyurethane foam, and used in a bench-scale continuous culture bioreactor to treat textile effluent for colour removal. The provision of soluble wheat starch (0.2% w/v) to the culture medium promoted growth of biomass and enhanced decolorisation of effluent in the bioreactor. The bioprocess was further combined with membrane filtration technology to improve the quality of treated effluent. The treated effluent showed 90, 82 and 60% reduction in COD, BOD5 and toxicity levels, respectively, and had potential for re-use in dyeing processes. The colour difference of the cotton fabrics dyed using the treated effluent samples compared to those dyed using normal supply water was found to be industrially acceptable. The described process could improve treatment efficiency and allow water recycling within the textile factory. 相似文献
76.
Pd/CeO2/Ta/Si model catalysts were prepared by spin coating and sputter deposition method, and characterized by means of AFM, SEM and in situ XPS, especially focusing on the redox properties of Ce and Pd elements. Compared with thin CeO2 films (about 2.2nm), the thicker ones (about 22nm) maintained Ce4+ oxidation state even after treatment with H2 up to 500°C while the presence of Pd facilitated the reduction of ceria. The reduction of ceria brought about following that of PdO, which was explained by the spillover of hydride in Pd to CeO2 originating from hydrogen adsorption on the Pd surface. Compared with the sputter deposition method, spin coating produced the smaller size of Pd particles, thus leading to formation of the stable PdO species against hydrogen. Based on these results, a schematic model of Pd/CeO2/Ta/Si was suggested and it might be assumed that spin coating method provided with an environment similar to the conventional impregnation. 相似文献
77.
Hyeong Do Kweon Eun Ju Heo Do Hwan Lee Jin Weon Kim 《Journal of Mechanical Science and Technology》2018,32(7):3137-3143
The true stress-strain curve of a material should be determined for plastic property input to numerical analysis. This study proposes a simple methodology for determining the true stress-strain curve of SA-508 Grade 3 Class 1 low alloy steel using limited information from a general tensile test with finite element analysis. Measured engineering stresses and strains can be reasonably converted to true stresses and strains under uniform deformation before necking. True stress-strains are difficult to determine after necking because of nonuniform deformation without specialized measurement techniques. Five post-necking strain hardening models are considered, namely, linear, swift, Ludwick, Hollomon-linear (HL) and Hollomon-linear-constant (HLC) models. The equations for each model can be determined using the results of the tensile test, which include the true stress-strain value at the maximum load point and the corrected true stress-strain value at the fracture point plus the Considere instability criterion. The HL and HLC models suggested that the engineering stress-strains from the finite element analysis are consistent with the experimental results. 相似文献
78.
Kyung Rae Ko Hyunil Lee Soo-Hong Han Wooyeol Ahn Do Kyung Kim Il-Su Kim Bo Sung Jung Soonchul Lee 《International journal of molecular sciences》2022,23(5)
A large number of studies have focused on the role of substance P (SP) and the neurokinin-1 receptor (NK1R) in the pathogenesis of a variety of medical conditions. This review provides an overview of the role of the SP-NK1R pathway in the pathogenesis of musculoskeletal disorders and the evidence for its role as a therapeutic target for these disorders, which are major public health problems in most countries. To summarize, the brief involvement of SP may affect tendon healing in an acute injury setting. SP combined with an adequate conjugate can be a regenerative therapeutic option in osteoarthritis. The NK1R antagonist is a promising agent for tendinopathy, rheumatoid arthritis, and osteoarthritis. Research on the SP-NK1R pathway will be helpful for developing novel drugs for osteoporosis. 相似文献
79.
Kotesh Kumar Mandari Anil Kumar Reddy Police Jeong Yeon Do Misook Kang Chan Byon 《International Journal of Hydrogen Energy》2018,43(4):2073-2082
In this experimental studies, we report the synthesis of TiO2 co-doped by both cationic and anionic sites by simple sol-gel based method. All the prepared samples exhibit the anatase crystalline morphology however, showed lattice distortion caused by the displacement of Ti4+ sites by Gd3+. The improved visible absorption is witnessed by the Gd and N co-doping with an assured redshift in the absorption edge. The N and Gd displacement inside TiO2 lattice accompanied by the creation of OTiN and GdOTi bonds are characterized by the X-ray photoelectron spectra. The strong resonance signal by Gd4f electrons in the electron paramagnetic resonance spectroscopy further substantiate the displacement of lattice cites of TiO2 by Gd3+ ions. The longevity of the photo produced charges observed in fluorescence spectra of Gd and N co-doped TiO2 is because of the effective transfer of charges to the defect sites. The aforementioned catalysts are tested for their capacity for the H2 production from water splitting. The 2 wt% gadolinium and nitrogen co-doped TiO2 has shown 10764 μmol g?1 H2 production which is 26 times higher than the commercial Degussa P-25 catalyst. The enhanced activity for hydrogen production can be attributed to factors such as increased absorptivity under visible light and effective charge carrier separation. 相似文献
80.
Vo Phuoc-Hung Nguyen Thai-Son Huynh Van-Thanh Do Thanh-Nghi 《Multimedia Tools and Applications》2018,77(21):28777-28797
Multimedia Tools and Applications - In this paper, we propose a novel reversible data hiding technique based on two-dimensional histogram shifting for quantized discrete cosine transformation... 相似文献