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51.
Hyun-Shik Yun Hongkyun Lee Young-Tae Park Min-Kyu Ji Akhil N. Kabra Chung Jeon Byong-Hun Jeon Jaeyoung Choi 《Applied biochemistry and biotechnology》2014,173(8):2054-2064
Microalgae were selected and isolated from acid mine drainage in order to find microalgae species which could be cultivated in low pH condition. In the present investigation, 30 microalgae were isolated from ten locations of acid mine drainage in South Korea. Four microalgae were selected based on their growth rate, morphology, and identified as strains of KGE1, KGE3, KGE4, and KGE7. The dry biomass of microalgae species ranged between 1 and 2 g L?1 after 21 days of cultivation. The growth kinetics of microalgae was well described by logistic growth model. Among these, KGE7 has the highest biomass production (2.05?±?0.35 g L?1), lipid productivity (0.82?±?0.14 g L?1), and C16–C18 fatty acid contents (97.6 %). These results suggest that Scenedesmus sp. KGE 7 can be utilized for biodiesel production based on its high biomass and lipid productivity. 相似文献
52.
Jinwon Jeon Dr. Yu-Tao He Sanghoon Shin Prof. Dr. Sungwoo Hong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(1):287-291
The photocatalyzed ortho-selective migration on a pyridyl ring has been achieved for the site-selective trifluoromethylative pyridylation of unactivated alkenes. The overall process is initiated by the selective addition of a CF3 radical to the alkene to provide a nucleophilic alkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho-position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well-suited for addition to the C2-position of pyridinium salts to ultimately provide synthetically valuable C2-fluoroalkyl functionalized pyridines. Moreover, the method was successfully applied to the reaction with P-centered radicals. The utility of this transformation was further demonstrated by the late-stage functionalization of complex bioactive molecules. 相似文献
53.
Jinny Claire Lee Hye Yun Kim Sejin Lee Jisu Shin Hyunjin Vincent Kim Kyeonghwan Kim Seungyeop Baek Donghee Lee Hanna Jeon DaWon Kim Seung‐Hoon Yang Gyoonhee Han Keunwan Park Jaeho Choi Jinwoo Park Jason A. Moss Kim D. Janda YoungSoo Kim 《Angewandte Chemie (International ed. in English)》2020,59(28):11491-11500
Amyloid‐β (Aβ) oligomers are implicated in Alzheimer disease (AD). However, their unstable nature and heterogeneous state disrupts elucidation of their explicit role in AD progression, impeding the development of tools targeting soluble Aβ oligomers. Herein parallel and anti‐parallel variants of Aβ(1–40) dimers were designed and synthesized, and their pathogenic properties in AD models characterized. Anti‐parallel dimers induced cognitive impairments with increased amyloidogenesis and cytotoxicity, and this dimer was then used in a screening platform. Through screening, two FDA‐approved drugs, Oxytetracycline and Sunitinib, were identified to dissociate Aβ oligomers and plaques to monomers in 5XFAD transgenic mice. In addition, fluorescent Astrophloxine was shown to detect aggregated Aβ in brain tissue and cerebrospinal fluid samples of AD mice. This screening platform provides a stable and homogeneous environment for observing Aβ interactions with dimer‐specific molecules. 相似文献
54.
Alkaline stable anion exchange membranes based on the cross-linked poly(arylene ether sulfone) grafted with dual quaternary piperidine (XPAES-DP) units were synthesized. The chemical structure of the synthesized PAES-DP was validated using 1H-NMR and FT-IR spectroscopy. The physicochemical, thermal, and mechanical properties of XPAES-DP membranes were compared with those of two linear PAES based membranes grafted with single piperidine (PAES-P) unit and conventional trimethyl amine (PAES-TM). XPAES-DP membrane showed the ionic conductivity of 0.021 S cm−1 at 40 °C which was much higher than that of PAES-P and PAES-TM because of the possession of more quaternary ammonium groups in the cross-linked structure. This cross-linked structure of the XPAES-DP membrane resulted in a higher tensile strength of 18.11 MPa than that of PAES-P, 17.09 MPa. In addition, as the XPAES-DP membrane shows consistency in the ionic conductivity even after 96 h in 3 M KOH solution with a minor change, its chemical stability was assured for the application of anion exchange membrane fuel cell. The single-cell assembled with XPAES-DP membrane displayed a power density of 109 mWcm−2 at 80 °C under 100% relative humidity. 相似文献
55.
Jeon Min-Kyung Kim Seunghee Hosseini Zadeh Amin Kwon Tae-Hyuk 《Transport in Porous Media》2020,133(2):207-227
Transport in Porous Media - We investigate viscous fluid flows and concurrent fluid-driven deformations in porous media. The hydro-mechanically (H-M) coupled pore-network model (PNM) is developed,... 相似文献
56.
Biotin-avidin mediated competitive enzyme-linked immunosorbent assay to detect residues of tetracyclines in milk 总被引:1,自引:0,他引:1
Tetracycline (TC) antibiotics are widely used for prevention and control of disease because they inhibit the growth of bacteria. However, the presence of TC antibiotics residues in food causes harmful effects on consumer's health such as allergic reactions, liver damage and gastrointestinal disturbance, so that many countries have set MRLs (maximum residue levels). Therefore, it is necessary to detect tetracycline residues, to develop suitable analytical techniques to be used as routine screens and field detection.A new approach to the biotin-avidin mediated competitive ELISA is developed to determine tetracycline residues in milk. After optimization, the LOD and LOQ were 1.0 × 10− 10 M (0.048 μg/L) and 1.0 × 10− 9 M, respectively, and the working range from 3.16 × 10− 10 M to 3.16 × 10− 7 M toward TC in milk. No cross-reactivity was observed with the structurally similar compounds; chlortetracycline (13.7%), oxytetracycline (10%) and doxytetracycline (< 1%). Additionally percent recoveries of TC spiked in milk were quite satisfactory (∼ 90%). Comparing our results obtained in this work with others, it shows with the capability to detect TC ranging in MRLs (100 μg/L in milk) sufficiently with highly sensitivity in milk, and with simple pre-treatment. In addition, this method can apply to developing useful ELISA test kit for determination of TCs in milk. 相似文献
57.
Min Ku Jeon Kweon Ho Kang Geun Il Park Young Soon Lee 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(2):513-517
Chlorination reaction behavior of Zircaloy-4 (Zry-4) cladding hulls was demonstrated by using a quartz reactor system. By
reacting at 380 °C for 3 h, mass of the Zry-4 hulls decreased by 65.8 wt% with Cl2 utilization of 87.1 mol%. Composition of collected product was analyzed and it was revealed that concentration of Zr was
higher than 99.97 wt%. The purity of Zr in the experimental result was higher than expectation when considering Sn (1.31 wt%)
and Fe (0.25 wt%) contents which can produce gaseous SnCl4 and FeCl3 at the experimental condition. Theoretical calculations were performed to clarify the high purity of Zr by using the HSC
code. The simulation results revealed that formation of ZrCl4 is more preferred than SnCl4, FeCl3, and CrCl3. The preference of chloride formation was confirmed by the theoretical calculation, and it was suggested that the major constituents
of Zry-4 might react with Cl2 to produce chlorides in an order of ZrCl4 > CrCl3 > SnCl4 > FeCl3. It was also suggested that continuous removal of ZrCl4 and sufficient supply of Zr source during the chlorination reaction might have contributed to the high purity of Zr. 相似文献
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60.
Kumar Sunil Jeon H. C. Kang T. W. Kalia Rajesh Sharma J. K. Panwar Sanjay Kalia Sapna Sharma Vandana Choubey R. K. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(13):2666-2670
Russian Journal of Physical Chemistry A - In the present work, the effect of temperature and moisture has been studied on nano-porous polycarbonate membranes of size 15, 50, and 80 nm, respectively... 相似文献