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991.
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
992.
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
993.
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
994.
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
995.
996.
Iseul Jeong Chae Bin Kim Dong‐Gue Kang Kwang‐Un Jeong Se Gyu Jang Nam‐Ho You Seokhoon Ahn Dai‐Soo Lee Munju Goh 《Journal of polymer science. Part A, Polymer chemistry》2019,57(6):708-715
To address tremendous needs for developing efficiently heat dissipating materials with lightweights, a series of liquid crystalline epoxy resins (LCEs) are designed and synthesized as thermally conductive matrix. All prepared LCEs possess epoxies at the molecular side positions and cyanobiphenyl mesogenic end groups. Based on several experimental results such as differential scanning calorimetry, polarized optical microscopy, and X‐ray diffraction, it is found that the LCEs exhibited liquid crystalline mesophases. When LCE is cured with a diamine crosslinker, the cured LCE maintains the oriented LC domain formed in the uncured state, ascribing to a presence of dipole–diploe and π–π interactions between cyanobiphenyl mesogenic end groups. Due to the anisotropic molecular orientation, the cured LCE exhibits a high thermal conductivity of 0.46 W m?1 K?1, which is higher than those of commercially available crystalline or amorphous epoxy resins. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 708–715 相似文献
997.
Lee Chang Hwa Kim Tack-Jin Yoon Dalsung Jang Junhyuk Kim Gha-Young Lee Sung-Jai 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):331-336
Journal of Radioanalytical and Nuclear Chemistry - U chlorination is demonstrated using electrochemical and chemical reactions with ZnCl2 in LiCl–KCl molten salts. Voltammetric studies... 相似文献
998.
Dr. Steffen Bähring Dr. Luis Martín‐Gomis Gunnar Olsen Prof. Dr. Kent A. Nielsen Dr. Dong Sub Kim Dr. Troels Duedal Prof. Dr. Ángela Sastre‐Santos Prof. Dr. Jan O. Jeppesen Prof. Dr. Jonathan L. Sessler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):1958-1967
Supramolecular polymers are a class of macromolecules stabilized by weak non‐covalent interactions. These self‐assembled aggregates typically undergo stimuli‐induced reversible assembly and disassembly. They thus hold great promise as so‐called functional materials. In this work, we present the design, synthesis, and responsive behavior of a short supramolecular oligomeric system based on two hetero‐complementary subunits. These “monomers” consist of a tetrathiafulvalene‐functionalized calix[4]pyrrole (TTF‐C[4]P) and a glycol diester‐linked bis‐2,5,7‐trinitrodicyanomethylenefluorene‐4‐carboxylate (TNDCF), respectively. We show that when mixed in organic solvents, such as CHCl3, CH2ClCH2Cl, and methylcyclohexane, supramolecular aggregation takes place to produce short oligomers stabilized by hydrogen bonding and donor–acceptor charge‐transfer (CT) interactions. The self‐associated materials were characterized by 1H NMR and UV/Vis/NIR absorption spectroscopy, as well as by concentration‐ and temperature‐dependent absorption spectroscopy and dynamic light scattering (DLS) analyses of both the monomeric and oligomerized species. The self‐associated system produced from TTF‐C[4]P and TNDCF exhibits a concentration‐dependent aggregation behavior typical of supramolecular polymers. Further support for the proposed self‐assembly came from theoretical calculations. The fluorescence emitting properties of TNDCF are quenched under conditions that promote the formation of supramolecular aggregates containing TTF‐C[4]P and TNDCF. This quenching effect has been utilized as a probe for the detection of substrates in the form of anions (i.e., chloride) and nitroaromatic explosives (i.e., 1,3,5‐trinitrobenzene). Specifically, the addition of these substrates to mixtures of TTF‐C[4]P and TNDCF produced a fluorescence “turn‐on” response. 相似文献
999.
1000.