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71.
2D Materials: Rotation‐Misfit‐Free Heteroepitaxial Stacking and Stitching Growth of Hexagonal Transition‐Metal Dichalcogenide Monolayers by Nucleation Kinetics Controls (Adv. Mater. 25/2015) 下载免费PDF全文
72.
73.
Moon Jae-Sung Kim Choonghyun Youm Youngil Bae Joonbum 《Journal of Mechanical Science and Technology》2018,32(5):2289-2298
Journal of Mechanical Science and Technology - This paper presents the design and modeling of the UNI-Copter, a portable spherical unmanned aerial vehicle (UAV) that is powered by a single rotor.... 相似文献
74.
Ko Hoon Kim Hye Ran Moon Junseong Lee Jae Nyoung Kim 《Advanced Synthesis \u0026amp; Catalysis》2015,357(4):701-708
The palladium‐catalyzed, one‐pot arylative cyclization of 3‐(γ,δ‐disubstituted)allylidene‐2‐oxindoles afforded spirodihydronaphthalene‐2‐oxindole frameworks via an oxidative Heck arylation (Fujiwara–Moritani reaction), an allylic palladium migration, and an aryl C H bond functionalization/arylation cascade of reactions. This is a first example of the palladium‐catalyzed oxidative arylation and an aryl C H bond functionalization/arylation cascade reaction which involves an electrophilic arylative quenching of a π‐allylpalladium intermediate and a regio‐controlled aryl C H bond activation assisted by a weak palladium‐arene interaction.
75.
We compared novel size‐selective separators, namely the textile fabrics of polyphenylene sulfide (PPS) and sulfonated polyphenylene sulfide (S‐PPS), and the nonwoven fabrics of polypropylene80 (PP 80) and PP 100, with commonly used ion exchange separators (Nafion 117 and cation exchange membane‐7000; CMI‐7000) in terms of power generation, oxygen diffusion, and biofilm formation in a single chamber microbial fuel cell. Size‐selective separators exhibited more power generation than ion selective separators. MFC operation with size‐selective separators generated power output ranging 0.407 to 0.591 V (1000 Ω), whereas with Nafion it was 0.272 V. In polarization analysis, S‐PPS resulted in the highest power density of 190 mW/m2, whereas it was 24 mW/m2 with Nafion‐117. Size selective separators showed similar or higher proton conductivity than Nafion 117. Oxygen mass transfer coefficients of size‐selective separators (KO = 3.7 ∼ 7.5 × 10−5) were lower or similar to Nafion (KO = 7.5 × 10−5). Fourier‐transform infrared spectroscopy and scanning electron microscopy analysis revealed that all separators (PP80, S‐PPS, and Nafion) contained proteins or carbon chain compounds after 300‐day operation, and however, Nafion 117 seems to be more susceptible to biofouling than the other separators. 相似文献
76.
A thermotropic liquid crystalline polyester (LCP) based on 4-hydroxyacetophenone azine and sebacoyl dichloride was synthesized via a low-temperature solution route. The liquid crystalline polymer was characterized by 1H-NMR, DSC, GPC, and polarizing microscopy experiments. The LCP was melt-blended with poly(butylene terephthalate) (PBT), followed by the melt-spinning process at take-up speeds ranging from 14 to 50 m/min. We analyzed the molecular orientational order of LCP and PBT in as-spun fibers of the LCP/PBT blends by the attenuated total reflection (ATR) FTIR dichroism technique and WAXS. The order parameter (S), representing the molecular orientational order, of LCP in the polyblend fibers increased as the employed LCP amounts and the draw ratio increased. Moreover, the order parameter of PBT in the blends increased dramatically when sufficiently large amounts of LCP (over 50 wt %) were employed, especially for highly drawn fibers, which suggested a considerable miscibility between LCP and PBT. The thermal behavior of the blends investigated by DSC also indicated that the synthesized LCP was miscible, at least partially, with PBT. All these results correlated with the enhancement of mechanical properties observed for higher concentrations of LCP in the blends and for highly drawn samples. © 1996 John Wiley & Sons, Inc. 相似文献
77.
Wenbin Zhang Chengsheng JiaYinjiao Wang Jin Moon KimPingping Jiang Xiaoming Zhang 《Food chemistry》2009
Lauryl mannoses were synthesized by lipase-catalyzed condensation using d-mannose and lauric acid in acetone in the presence of molecular sieves at 50 °C. 6-O-Lauryl mannose, 1,6-di-O-lauryl mannose, 3,6-di-O-lauryl mannose, and 4,6-di-O-lauryl mannose were isolated and identified by FT-IR, MS, and NMR. 相似文献
78.
You JY Moon BM Oh IG Baek BK Li LG Kim BS Stein BD Lee JH 《International journal of food microbiology》2006,106(1):74-78
Of 45 Escherichia coli O157 isolates from cattle feces, which were collected between May 2000 and September 2003 in Korea, 32 were resistant to at least 1 antibiotic and 28 were resistant to 4 or more antibiotics, with 32, 30 and 30 of the isolates being resistant to streptomycin, tetracycline and sulfisoxazole, respectively. Two isolates were resistant to fluoroquinolones and to 10 or more of the 22 other antimicrobial agents that were tested. Thirteen antimicrobial resistant patterns were observed. The most frequent resistance type, which was found for 11 isolates, was streptomycin-tetracycline-kanamycin-ampicillin-piperacillin-cephalothin-sulfisoxazole-ticarcillin. Polymerase chain reaction (PCR) analysis of the isolates for E. coli O157 virulence markers revealed that 25 of the resistant E. coli O157 isolates tested positive for stx2 or both stx1 and stx2 genes. These findings suggest that many of the resistant E. coli O157 isolates might cause disease in humans. 相似文献
79.
Jo Wol Soon Kim Sung Dae Jeong Soo Kyung Oh Su Jung ParK Moon Taek Lee Chang Geun Kang Young- Rok Jeong Min Ho 《Food science and biotechnology》2022,31(4):433-441
Food Science and Biotechnology - Resveratrol is known to have anti-inflammatory properties. However, high-dose resveratrol is required for optimal anti-inflammatory effects. HS-1793 is a derivative... 相似文献
80.
The effects of sample size, liquid loading, particle size, column length, and column temperature on retention volumes were
studied and separation factor, column efficiency, partition coefficient, and heat of solution were also obtained by gas-liquid
chromatography. The feed materials were chosen by similar boiling points as diethylether, dimethoxymethane and dichloromethane.
The relations between retention volume and above mentioned various variables were obtained. Separation factor was more affected
by column temperature than other variables, and decreased with the temperature. HETP increased almost linearly with sample
size. From the exponential relationship between partition coefficient and column temperature heat of solution of each material
was calculated. 相似文献