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排序方式: 共有88条查询结果,搜索用时 15 毫秒
1.
Aldoximes are readily dehydrated to nitriles with Raney nickel in refluxing 2-propanol. 相似文献
2.
A mechanistic study was carried out for the asymmetric Michael addition reaction of malonates to enones catalyzed by a primary amino acid lithium salt to elucidate the origin of the asymmetric induction. A primary β-amino acid salt catalyst, O-TBDPS β-homoserine lithium salt, exhibited much higher enantioselectivity than that achieved with the corresponding catalysts derived from α- and γ-amino acids for this reaction. Detailed studies of the transition states with DFT calculations revealed that the lithium cation and carboxylate group of the β-amino acid salt catalyst have important roles in achieving high enantioselectivity in the Michael addition reaction of malonates to enones. 相似文献
3.
A new high: Cannabis as a budding source of carbon-based materials for electrochemical power sources
Zahra I. Rana Ami R. Shah Alice V. Llewellyn Katrina Mazloomian Patricia McAlernon Thomas S. Miller Patrick L. Cullen Paul R. Shearing Dan J.L. Brett 《Current Opinion in Electrochemistry》2022
Cannabis sativa L., a low-cost, fast-growing herbaceous plant, is seeing a resurgence in widespread cultivation as a result of new policies and product drive. Its biodegradable and environmentally benign nature coupled with its high specific surface area and three-dimensional hierarchal structure makes it an excellent candidate for use as a biomass-derived carbon material for electrochemical power sources. It is proposed that this ‘wonder crop’ could have an important role in the energy transition by providing high-functioning carbon-based materials for electrochemistry. In this article, all instances of C. sativa usage in batteries, fuel cells and supercapacitors are discussed with a focus on highlighting the high capacity, rate capability, capacitance, current density and half-wave potential that can be achieved with its utilisation in the field. 相似文献
4.
Ami Viselter 《Journal of Functional Analysis》2009,256(2):594-602
We provide a necessary and sufficient condition for the representability of a function as the classical multidimensional Laplace transform, when the support of the representing measure is contained in some generalized semi-algebraic set. This is done by employing a method of Putinar and Vasilescu [M. Putinar, F.-H. Vasilescu, Solving moment problems by dimensional extension, Ann. of Math. (2) 149 (3) (1999) 1087-1107] for the corresponding multidimensional moment problem. 相似文献
5.
Ana Amić Zoran Marković Jasmina M. Dimitrić Marković Dejan Milenković Bono Lučić 《Molecular physics》2013,111(2):207-217
ABSTRACTParticipation of guaiacyl moiety of 3,5-dihydroxy-4-methoxybenzyl alcohol (DHMBA) in inactivation of free radicals was investigated using the DFT method. The thermodynamics of triple (3H+/3e?) free radical scavenging mechanisms was investigated. The Gibbs free energies of reactions of inactivation of selected 10 free radicals indicate DHMBA as a potent scavenger. Obtained results allow us to suggest that the contribution of guaiacyl moiety to antioxidant activity of phenolic compounds should be taken into account, what has been scarcely considered until now. 相似文献
6.
Using mean field theory and high temperature expansions the transition temperature, entropy jump and heat capacity are calculated in the recent microscopic model of defect melting proposed by Kleinert. The results are compared with the experimental data for almost isotropic substances. 相似文献
7.
Ami Mamolo Tristram Bogart 《International Journal of Mathematical Education in Science & Technology》2013,44(5):615-623
This article presents a novel re-conceptualisation to a well-known problem – The Ping-Pong Ball Conundrum. We introduce a variant of this super-task by considering it through the lens of ‘measuring infinity’ – a conceptualisation of infinity that extrapolates measuring properties of numbers, rather than cardinal properties. This approach is consistent with a nonstandard analysis approach to infinite numbers, and gives credence to the intuitive (but otherwise normatively incorrect) resolution. We explore the mathematical motivation and consequences of this variant, as well as offer further ‘riffs’ on the infinite ball problem for consideration. 相似文献
8.
Ami Saito Dr. Tomohisa Sawada Prof. Dr. Makoto Fujita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20547-20550
Porous metal complexes enable single-crystal X-ray crystallographic observation of included guests or reaction intermediates through simple soaking with the guests/substrates. Previous studies on this technique have often encountered difficulties in the observation of chiral structures because the host frameworks had no chirality. We synthesized a new metal–peptide porous complex through a folding-and-assembly strategy and utilized the chiral pore for trapping chiral guests. Chiral alcohols and ketones were successfully included within the pore. Crystallographic analyses clearly revealed not only their chemical structures but also chiral transformation events within the pore such as fixed conformations or an unstable hemiacetal formation. 相似文献
9.
Segmented conjugated macromolecules containing silicon and boron: ADMET synthesis and luminescent properties 下载免费PDF全文
Arijit Sengupta Ami Doshi Frieder Jäkle Ralf M. Peetz 《Journal of polymer science. Part A, Polymer chemistry》2015,53(14):1707-1718
Boron‐ and silicon‐containing conjugated homo‐ and copolymers could be synthesized using acyclic diene metathesis (ADMET) condensation of bis‐styryl monomers. Both, tri‐and tetra‐coordinated boron monomers were successfully polymerized forming homopolymers, or random copolymers (if polymerized together with a silicon containing co‐monomer). Polymer molecular weights Mn were measured at ~6000 to 15,000 g/mol (NMR end group analysis) with molecular weight distributions Mw/Mn ~1.8 to 2.2. The polymers absorbed at λmax ~317 to 406 nm and emitted at λmax ~370 to 494 nm with fluorescent quantum efficiencies ~24 to 48%. The copolymer with tri‐coordinate boron showed highly efficient fluorescence quenching in the presence of fluoride ions at ratios boron/fluoride ~5/1, demonstrating its potential as anion sensor. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1707–1718 相似文献
10.