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91.
Weijin Li Song Xue Sebastian Watzele Shujin Hou Johannes Fichtner A. Lisa Semrau Liujiang Zhou Alexander Welle Aliaksandr S. Bandarenka Roland A. Fischer 《Angewandte Chemie (International ed. in English)》2020,59(14):5837-5843
Metal–organic frameworks (MOFs) and their derivatives are considered as promising catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), which are important for many energy provision technologies, such as electrolyzers, fuel cells and some types of advanced batteries. In this work, a “strain modulation” approach has been applied through the use of surface‐mounted NiFe‐MOFs in order to design an advanced bifunctional ORR/OER electrocatalyst. The material exhibits an excellent OER activity in alkaline media, reaching an industrially relevant current density of 200 mA cm?2 at an overpotential of only ≈210 mV. It demonstrates operational long‐term stability even at a high current density of 500 mA cm?2 and exhibits the so far narrowest “overpotential window” ΔEORR‐OER of 0.69 V in 0.1 m KOH with a mass loading being two orders of magnitude lower than that of benchmark electrocatalysts. 相似文献
92.
Lisa Pisaniello Flynn Watson Tracey Siebert Leigh Francis Josh L. Hixson 《Molecules (Basel, Switzerland)》2022,27(7)
The winemaking by-product grape marc (syn. pomace) contains significant quantities of latent flavour in the form of flavour precursors which can be extracted and used to modulate the volatile composition of wine via chemical hydrolysis. Varietal differences in grapes are widely known with respect to their monoterpene content, and this work aimed to extend this knowledge into differences due to cultivar in volatiles derived from marc precursors following wine-like storage conditions. Marc extracts were produced from floral and non-floral grape lots on a laboratory-scale and from Muscat Gordo Blanco marc on a winery -scale, added to a base white wine for storage over five to six months, before being assessed using a newly developed membrane-assisted solvent extraction gas chromatography-mass spectrometry (GC-MS) method. The geraniol glucoside content of the marc extracts was higher than that of juices produced from each grape lot. In all wines with added marc extract from a floral variety, geraniol glucoside concentration increased by around 150–200%, with increases also observed for non-floral varieties. The relative volatile profile from extracts of the floral varieties was similar but had varied absolute concentrations. In summary, while varietally pure extracts would provide the greatest control over flavour outcomes when used in winemaking, aggregated marc parcels from floral cultivars may provide a mechanism to simplify the production logistics of latent flavour extracts for use in the wine sector. 相似文献
93.
Peter A. Jacobi Lisa M. Armacost Joseph I. Kravitz Michael J. Martinelli Harold G. Selnick 《Tetrahedron letters》1988,29(52):6865-6868
Bis-acetylenic alcohols of proper design undergo a facile oxy-Cope rearrangement to afford mixtures of E- and Z-enynones. These latter compounds afford methylenecyclopentenones upon enolization and electrocyclic ring closure. 相似文献
94.
Benjamin Byerly Kevin Kuhn Lisa Colletti Lynn Foster Russ Keller Elmer Lujan Alex Martinez Donivan Porterfield Dan Schwartz Khal Spencer Floyd Stanley Mariam Thomas Lisa Townsend Ning Xu Lav Tandon 《Journal of Radioanalytical and Nuclear Chemistry》2017,312(1):95-104
Thorough physical and chemical characterization of plutonium–beryllium (PuBe) neutron sources is an important capability with applications ranging from material accountancy to nuclear forensics. Characterization of PuBe sources is not trivial owing to range of existing source designs and the need for adequate infrastructure to deal with radiation and protect the analyst. This study demonstrates a method for characterization of three PuBe sources that includes physical inspection and imaging followed by controlled disassembly and destructive analysis. 相似文献
95.
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97.
[reaction: see text] The syntheses of 4,4a-didehydrohimbacine and 4,4a-didehydrohimandravine are presented. Key steps include an intramolecular Diels-Alder reaction of a bromopentadienyl acrylate and Suzuki-Miyaura and Stille coupling reactions. 相似文献
98.
We show that perturbative high scale unification and a solution to the hierarchy problem are possible with extra dimensions in the context of the warped geometry of 5D anti-de Sitter space ( AdS(5)). This is possible because the couplings for bulk gauge bosons run logarithmically below the AdS(5) curvature scale. The calculation is done in five dimensions, rather than in the effective theory, which is strongly coupled above the TeV scale. 相似文献
99.
Joel A Dietz Yan Li Lisa M Chung Brian S Yandell Cassandra L Schlamp Robert W Nickells 《BMC neuroscience》2008,9(1):74
Background
Intrinsic apoptosis of neuronal somas is one aspect of neurodegenerative diseases that can be influenced by genetic background. Genes that affect this process may act as susceptibility alleles that contribute to the complex genetic nature of these diseases. Retinal ganglion cell death is a defining feature of the chronic and genetically complex neurodegenerative disease glaucoma. Previous studies using an optic nerve crush procedure in inbred mice, showed that ganglion cell resistance to crush was affected by the Mendelian-dominant inheritance of 1–2 predicted loci. To assess this further, we bred and phenotyped a large population of F2 mice derived from a resistant inbred strain (DBA/2J) and a susceptible strain (BALB/cByJ). 相似文献100.