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991.
Photocatalytic overall water splitting with dual-bed system under visible light irradiation 总被引:1,自引:0,他引:1
Sang Won Bae Sang Min JiSuk Joon Hong Ji Wook JangJae Sung Lee 《International Journal of Hydrogen Energy》2009
Photocatalytic overall water splitting has been demonstrated with WO3 for oxygen producing photocatalyst (OPC), and Rh-doped SrTiO3 for hydrogen producing photocatalyst (HPC) in a simulated dual-bed system under visible light irradiation (λ ≥ 400 nm). The Fe3+/Fe2+ redox couple was chosen as the most effective electron mediator between OPC and HPC. The overall performance of the dual-bed system was limited by the low activity of HPC, and thus the activity of HPC should be increased to improve the overall performance. For overall water splitting reaction in a dual-bed system, the conduction band of OPC must be more negative than the redox potential of the electron acceptors and the valence band of HPC must be more positive than the redox potential of the electron donors. 相似文献
992.
993.
This letter proposes a complexity reduction method to speed up the noiseless decoding of a bit-sliced arithmetic coding (BSAC) decoder. This scheme fully utilizes the group of consecutive arithmetic-coded symbols known as the decoding band and the significance tree structure sorted in order of significance at every decoding band. With the same audio quality, the proposed method reduces the number of calculations that are performed during the noiseless decoding in BSAC to about 22% of the amount of calculations with the conventional full-search method. 相似文献
994.
995.
996.
Yong Hui Lee Sang Hyuk Im Jeong Ah Chang Jong-Heun Lee Sang Il Seok 《Organic Electronics》2012,13(6):975-979
CdSe-sensitized heterojunction solar cells composed of mesoscopic TiO2/CdSe/P3HT (poly-3-hexylthiophene) were constructed, and the negative molecular dipole of 4-methoxybenzenethiol (MBT) and the ZnS passivation layer were used as interface modifiers to improve device performance. Through the interface modification between TiO2/CdSe and P3HT using MBT and by ZnS surface passivation, the power conversion efficiency of the modified solar cell was greatly enhanced from 1.02% to 1.62% under 1 sun illumination. 相似文献
997.
Md. Dulal Hossain Junghoon Moon Hyoung Goo Kang Sung Chul Lee Young Chan Choe 《Scientometrics》2012,90(1):57-83
Triple helix (TH) collaborations involving university, industry and government provide a networked infrastructure for shaping
the dynamic fluxes of knowledge base of innovations locally and these fluxes remain emergent within the domains. This study
maps these emergence dynamics of the knowledge base of innovations of Research & Development (R&D) by exploring the longitudinal
trend of systemness within the networked research relations in Bangladesh on the TH model. The bibliometric data of publications
collected from the Science Citation Index (SCI), the social sciences and the arts and humanities for analysis of science indicators
and the patent data collected from the US Patent Office to analyze the patent success ratio as a measure of innovation within
TH domains. The findings show that the network dynamics have varied considerably according to the R&D policies of the government.
The collaboration patterns of co-authorship relations in the SCI publications prominently increased, with some variation,
from 1996 to 2006. Nevertheless, inter-institutional collaboration negatively influenced by the national science and technology
(S&T) research policies in the last 5 years due to their evaluation criteria. Finally, the findings reveal that the R&D system
of Bangladesh is still undergoing a process of institutionalizing S&T and has failed to boost its research capacity for building
the knowledge base of innovations by neglecting the network effects of TH dynamics. 相似文献
998.
Development of a green two‐dimensional HPLC‐DAD/ESI‐MS method for the determination of anthocyanins from Prunus cerasifera var. atropurpurea leaf and improvement of their stability in energy drinks 下载免费PDF全文
Fang‐Fang Chen Jie Sang Yao Zhang Jun Sang 《International Journal of Food Science & Technology》2018,53(6):1494-1502
This study aimed to develop a green two‐dimensional HPLC‐DAD/ESI‐MS method for analysing anthocyanins from Prunus cerasifera var. atropurpurea leaf and improve their stability in energy drinks by the addition of phenolic acids. Ethanol and tartaric acid solutions were used as mobile phases for one‐dimensional HPLC‐DAD for quantitative analysis of anthocyanins, and the primary anthocyanins were identified as cyanidin‐3‐O‐galactoside, cyanidin‐3‐O‐glucoside and cyanidin‐3‐O‐rutinoside using two‐dimensional HPLC‐MS. Method validation showed that the developed method was accurate, stable and reliable for the analysis of P. cerasifera anthocyanins. The effects of gallic, ferulic and caffeic acid on the stability of cyanidin‐3‐O‐galactoside, cyanidin‐3‐O‐glucoside, cyanidin‐3‐O‐rutinoside and total anthocyanins from P. cerasifera leaf in energy drinks were evaluated, and the degradation of P. cerasifera anthocyanins ideally followed a first‐order model (R2 > 0.98). Gallic acid showed stronger protective effects on P. cerasifera anthocyanins in energy drinks, and adding/increasing ferulic and caffeic acids accelerated the degradation reactions. 相似文献
999.
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
1000.
Effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of a sailfin sandfish (Arctoscopus japonicus) fish sauce 下载免费PDF全文
Byoung‐Mok Kim Jae‐Ho Park Dong‐Soo Kim Young‐Myung Kim Joon‐Young Jun In‐Hak Jeong Si‐Youl Nam Young‐Min Chi 《International Journal of Food Science & Technology》2016,51(8):1888-1899
The effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of fish sauce produced from sailfin sandfish (Arctoscopus japonicus) with different salt concentrations (10% and 20%) were investigated over 10 months. Fish sauces prepared from sailfin sandfish with rice koji and a low salt concentration had higher total nitrogen, amino nitrogen and total free amino acid than did those without rice koji or with a high salt concentration. Sensory evaluation of fish sauces prepared with rice koji and a low salt concentration found better taste, flavour and overall acceptance than those prepared without rice koji during fermentation (P < 0.05). The use of rice koji increased the total nitrogen, amino nitrogen and free amino acid and also enhanced the sensory qualities during fermentation. These results suggest that the use of rice koji can result in a low‐salt fish sauce with better flavour. 相似文献