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991.
Tae-Wook Kim Seul-Kee Kim Sungkyun Park Kang Hyun Park Jae-Myung Lee 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):145-159
The present study investigated thermal and mechanical characteristics of irradiated polyurethane foams (PUFs) according to the irradiation does under various temperature conditions, including low/cryogenic temperatures. Fourier transform infrared analysis was performed to obtain information on the PUF molecular structure. In addition, Macro- and microstructural investigations were carried out to determine the relationship between thermal and mechanical characteristics and irradiation dose. The test results were quantitatively presented, and it was found that the irradiated PUF has potential for application in industrial structures. 相似文献
992.
993.
Daniel P. Sweat Xiang Yu Myungwoong Kim Padma Gopalan 《Journal of polymer science. Part A, Polymer chemistry》2014,52(10):1458-1468
Living anionic polymerization of an acetal protected 4‐hydroxystyrene monomer, (4‐(2‐tetrahydropyranyloxy)styrene) (OTHPSt), and the chain extension of the poly(OTHPSt) anion with a variety of monomers including styrene, 4‐tert‐butylstyrene, methacryloyl polyhedral oligomeric silsesquioxane (MAPOSS) and hexamethylcyclotrisiloxane is demonstrated. The P(OTHPSt) homopolymer has a glass transition temperature well above room temperature, which facilitates handling and purification of the protected poly(4‐hydroxystyrene) (PHS). The resulting diblock copolymers have narrow dispersities <1.05. Chemoselective mild deprotection conditions for the P(OTHPSt) block were identified to prevent simultaneous degradation of the MAPOSS or dimethylsiloxane (DMS) block, thus allowing for the first reported synthesis of P(HS‐b‐DMS) and P(HS‐b‐MAPOSS). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1458–1468 相似文献
994.
T. Kim 《Russian Journal of Mathematical Physics》2012,19(2):193-196
In the paper, we derive an analog of the Lebesgue-Radon-Nikodym theorem with respect to fermionic p-adic invariant measure on ? p . 相似文献
995.
996.
Journal of the Korean Physical Society - In intensity-modulated radiosurgery (IMRS) treatment, radiation delivery techniques require the ability to accurately verify complex three-dimensional (3D)... 相似文献
997.
Dr. Oleksii Zozulia Dr. Liam R. Marshall Dr. Inhye Kim Eric M. Kohn Prof. Dr. Ivan V. Korendovych 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(17):5388-5392
The self-assembly of short peptides gives rise to versatile nanomaterials capable of promoting efficient catalysis. We have shown that short, seven-residue peptides bind hemin to produce functional catalytic materials which display highly efficient peroxidation activity, reaching a catalytic efficiency of 3×105 m −1 s−1. Self-assembly is essential for catalysis as non-assembling controls show no activity. We have also observed peroxidase activity even in the absence of hemin, suggesting the potential to alter redox properties of substrates upon association with the assemblies. These results demonstrate the practical utility of self-assembled peptides in various catalytic applications and further support the evolutionary link between amyloids and modern-day enzymes. 相似文献
998.
N-substituted anilines react with triethanolamine in the presence of a catalytic amount of a homogeneous ruthenium catalyst to give the corresponding 1-substituted indoles in good yields. 相似文献
999.
Bert C. Lynn Jesus V. Mallén Servando Muñoz Minsook Kim George W. Gokel 《Supramolecular chemistry》2013,25(3-4):195-197
Abstract Bola-amphiphiles having two aza-18-crown-6 ether rings attached by a covalent spacer (O—O) and an analogous tris (macrocycle) (O—O—O) have been prepared and their cation complexation behavior has been assessed by fast atom bombardment and collisionally activated dissociation tandem mass spectrometry; the key finding is that two cations may simultaneously be complexed by a two- or three-crown system and that this complexation may also involve an anion. 相似文献
1000.
Dr. Sumith A. Kularatne Vishal Deshmukh Dr. Marco Gymnopoulos Dr. Sandra L. Biroc Dr. Jinming Xia Shailaja Srinagesh Dr. Ying Sun Dr. Ning Zou Dr. Mark Shimazu Dr. Jason Pinkstaff Dr. Semsi Ensari Nick Knudsen Anthony Manibusan Dr. Jun Y. Axup Dr. Chan Hyuk Kim Prof. Vaughn V. Smider Dr. Tsotne Javahishvili Prof.Dr. Peter G. Schultz 《Angewandte Chemie (International ed. in English)》2013,52(46):12101-12104