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1. Recent Advances in Dual Triplet Ketone/Transition-Metal Catalysis

   https://doi.org/10.1055/s-0042-1751444  

   Iziumchenko, Valeriia; Gevorgyan, Vladimir (July 2023, Synlett)

   Abstract Dual light-excited ketone/transition-metal catalysis is a rapidly developing field of photochemistry. It allows for versatile functionalizations of C–H or C–X bonds enabled by triplet ketone acting as a hydrogen-atom-abstracting agent, a single-electron acceptor, or a photosensitizer. This review summarizes recent developments of synthetically useful transformations promoted by the synergy between triplet ketone and transition-metal catalysis. 1 Introduction 2 Triplet Ketone Catalysis via Hydrogen Atom Transfer 2.1 Triplet Ketones with Nickel Catalysis 2.2 Triplet Ketones with Copper Catalysis 2.3 Triplet Ketones with Other Transition-Metal Catalysis 3 Triplet Ketone Catalysis via Single-Electron Transfer 4 Triplet Ketone Catalysis via Energy Transfer 5 Conclusions 

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2. Averages Along the Primes: Improving and Sparse Bounds

   https://doi.org/10.1515/conop-2020-0003  

   Han, Rui; Krause, Ben; Lacey, Michael T.; Yang, Fan (February 2020, Concrete Operators)

   Abstract Consider averages along the prime integers ℙ given by {\mathcal{A}_N}f(x) = {N^{ - 1}}\sum\limits_{p \in \mathbb{P}:p \le N} {(\log p)f(x - p).} These averages satisfy a uniform scale-free ℓ p -improving estimate. For all 1 < p < 2, there is a constant C p so that for all integer N and functions f supported on [0, N ], there holds {N^{ - 1/p'}}{\left\| {{\mathcal{A}_N}f} \right\|_{\ell p'}} \le {C_p}{N^{ - 1/p}}{\left\| f \right\|_{\ell p}}. The maximal function 𝒜 * f = sup N |𝒜 N f | satisfies ( p , p ) sparse bounds for all 1 < p < 2. The latter are the natural variants of the scale-free bounds. As a corollary, 𝒜 * is bounded on ℓ p ( w ), for all weights w in the Muckenhoupt 𝒜 p class. No prior weighted inequalities for 𝒜 * were known. 

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3. A carbene-stabilized diphosphorus: a triple-bonded diphosphorus (PP) and a bis(phosphinidene) (P–P) transfer agent

   https://doi.org/10.1039/D4SC05091F  

   Yoon, Joseph S; Abdellaoui, Mehdi; Gembicky, Milan; Bertrand, Guy (October 2024, Chemical Science)

   The bis-monosubstituted aminocarbene-P₂adduct is a generator of P₂, under the classical triple-bonded form (PP), but it also acts as a bis(phosphinidene) (P–P) synthetic equivalent. 

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4. Bacterial Community Structure Modulates Soil Phosphorus Turnover at Early Stages of Primary Succession

   https://doi.org/10.1029/2024GB008174  

   Wang, Yuhan; Bing, Haijian; Moorhead, Daryl L; Hou, Enqing; Wu, Yanhong; Wang, Jipeng; Duan, Chengjiao; Cui, Qingliang; Zhang, Zhiqin; Zhu, He; et al (October 2024, Global Biogeochemical Cycles)

   Abstract Microbes are the drivers of soil phosphorus (P) cycling in terrestrial ecosystems; however, the role of soil microbes in mediating P cycling in P‐rich soils during primary succession remains uncertain. This study examined the impacts of bacterial community structure (diversity and composition) and its functional potential (absolute abundances of P‐cycling functional genes) on soil P cycling along a 130‐year glacial chronosequence on the eastern Tibetan Plateau. Bacterial community structure was a better predictor of soil P fractions than P‐cycling genes along the chronosequence. After glacier retreat, the solubilization of inorganic P and the mineralization of organic P were significantly enhanced by increased bacterial diversity, changed interspecific interactions, and abundant species involved in soil P mineralization, thereby increasing P availability. Although 84% of P‐cycling genes were associated with organic P mineralization, these genes were more closely associated with soil organic carbon than with organic P. Bacterial carbon demand probably determined soil P turnover, indicating the dominant role of organic matter decomposition processes in P‐rich alpine soils. Moreover, the significant decrease in the complexity of the bacterial co‐occurrence network and the taxa‐gene‐P network at the later stage indicates a declining dominance of the bacterial community in driving soil P cycling with succession. Our results reveal that bacteria with a complex community structure have a prominent potential for biogeochemical P cycling in P‐rich soils during the early stages of primary succession. 

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5. The Liouville theorem for $$p$$-harmonic functions and quasiminimizers with finite energy

   https://doi.org/10.1007/s00209-020-02536-2  

   Björn, Anders; Björn, Jana; Shanmugalingam, Nageswari (February 2021, Mathematische Zeitschrift)

   null (Ed.)

   Abstract We show that, under certain geometric conditions, there are no nonconstant quasiminimizers with finite p th power energy in a (not necessarily complete) metric measure space equipped with a globally doubling measure supporting a global $$p$$ p -Poincaré inequality. The geometric conditions are that either (a) the measure has a sufficiently strong volume growth at infinity, or (b) the metric space is annularly quasiconvex (or its discrete version, annularly chainable) around some point in the space. Moreover, on the weighted real line $$\mathbf {R}$$ R , we characterize all locally doubling measures, supporting a local $$p$$ p -Poincaré inequality, for which there exist nonconstant quasiminimizers of finite $$p$$ p -energy, and show that a quasiminimizer is of finite $$p$$ p -energy if and only if it is bounded. As $$p$$ p -harmonic functions are quasiminimizers they are covered by these results. 

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