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Central European Journal of Operations Research - Multicriteria decision-making methods are widely spread and used to assist the decision-makers to resolve problems. Many of the methods are simple... 相似文献
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Alexandru Vlasceanu Dr. Søren L. Broman Anne S. Hansen Anders B. Skov Prof. Dr. Martina Cacciarini Prof. Dr. Anders Kadziola Prof. Dr. Henrik G. Kjaergaard Prof. Dr. Kurt V. Mikkelsen Prof. Dr. Mogens Brøndsted Nielsen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10796-10800
The conversion and efficient storage of solar energy is recognized to hold significant potential with regard to future energy solutions. Molecular solar thermal batteries based on photochromic systems exemplify one possible technology able to harness and apply this potential. Herein is described the synthesis of a macrocycle based on a dimer of the dihydroazulene/vinylheptafulvene (DHA/VHF) photo/thermal couple. By taking advantage of conformational strain, this DHA–DHA macrocycle presents an improved ability to absorb and store incident light energy in chemical bonds (VHF–VHF). A stepwise energy release over two sequential ring‐closing reactions (VHF→DHA) combines the advantages of an initially fast discharge, hypothetically addressing immediate energy consumption needs, followed by a slow process for consistent, long‐term use. This exemplifies another step forward in the molecular engineering and design of functional organic materials towards solar thermal energy storage and release. 相似文献
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Samuel Clark Ligon Konstanze Seidler Christian Gorsche Markus Griesser Norbert Moszner Robert Liska 《Journal of polymer science. Part A, Polymer chemistry》2016,54(3):394-406
The rapid and uncontrolled nature of network formation from di(meth)acrylate monomers produces high shrinkage stress and results in polymers with oftentimes brittle mechanical properties. Methods for regulating polymerization and network formation are sought. One option is the use of addition–fragmentation chain transfer (AFCT) agents, which are well known to control molecular weight and molecular weight distribution of monofunctional (meth)acrylates. A series of novel and previously described AFCT reagents were synthesized and screened with laser flash photolysis to determine reactivity. Well‐performing AFCT reagents were then tested in polymerizations with monofunctional and difunctional methacrylates. With monofunctional monomers, the molecular weight and polydispersity of the resultant linear polymers tend to decrease with the addition of AFCT agent. In copolymerization with dimethacrylate monomers, the AFCT agents were found to substantially lower and sharpen the glass transition. Sharpness of the glass transition is here indicative of a more regular and homogenous network. After coupling of the instruments, photorheology was performed simultaneously with real‐time IR to show an increase in monomer conversion at the time of gelation, which appears to have a positive effect on reducing shrinkage stress. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 394–406 相似文献
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Klmov Martina Krausov Ivana Orsk Maty Chvtil David 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(7):3195-3201
Journal of Radioanalytical and Nuclear Chemistry - The mass fractions of V, Cr, Co, Ni, Cu, Zn, As, Br, Mo, Cd, W, Hg, and Pb in soil of the Czech dump-side were measured by instrumental neutron... 相似文献
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Emilie Boulard Vivien Zibulski Luisa Oertel Dr. Philip Lienau Dr. Martina Schäfer Dr. Ursula Ganzer Dr. Ulrich Lücking 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4378-4388
A short synthetic approach with broad scope to access five- to seven-membered cyclic sulfoximines in only two to three steps from readily available thiophenols is reported. Thus, simple building blocks were converted to complex molecular structures by a sequence of S-alkylation and one-pot sulfoximine formation, followed by intramolecular cyclization. Seventeen structurally diverse cyclic sulfoximines were prepared in high overall yields. In vitro evaluation of these underrepresented, three-dimensional, cyclic sulfoximines with respect to properties relevant to medicinal chemistry did not reveal any intrinsic flaw for application in drug discovery. 相似文献