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401.
We will show that skew polynomial rings in several variables over locally nilpotent rings cannot contain nonzero idempotent elements. We will also prove that such rings are Brown–McCoy radical. 相似文献
402.
Hurwitz numbers count genus g, degree d covers of ℙ1 with fixed branch locus. This equals the degree of a natural branch map defined on the Hurwitz space. In tropical geometry, algebraic curves are replaced by certain piece-wise linear objects called tropical curves. This paper develops a tropical counterpart of the branch map and shows that its degree recovers classical Hurwitz numbers. Further, the combinatorial techniques developed are applied to recover results of Goulden et al. (in Adv. Math. 198:43–92, 2005) and Shadrin et al. (in Adv. Math. 217(1):79–96, 2008) on the piecewise polynomial structure of double Hurwitz numbers in genus 0. 相似文献
403.
Michael O. Albertson Hannah Alpert sarah‐marie belcastro Ruth Haas 《Journal of Graph Theory》2010,63(1):68-81
We prove that if G is a triangulation of the torus and χ(G)≠5, then there is a 3‐coloring of the edges of G so that the edges bounding every face are assigned three different colors. © 2009 Wiley Periodicals, Inc. J Graph Theory 63: 68–81, 2010 相似文献
404.
Louis Hitler Isang Bartholomew B. Unimuke Tomsmith O. Gber Terkumbur E. Amodu Ismail O. Ikeuba Alexander I. Adeyinka Adedapo S. 《Journal of Solid State Electrochemistry》2023,27(1):47-59
Journal of Solid State Electrochemistry - The rising costs of lithium and other versatile metals which are of electrochemical importance have sprouted concerns in the electrochemical world. Sodium... 相似文献
405.
Dr. Bernhard von Vacano Dr. Hannah Mangold Dr. Guido W. M. Vandermeulen Dr. Glauco Battagliarin Dr. Maximilian Hofmann Dr. Jessica Bean Dr. Andreas Künkel 《Angewandte Chemie (International ed. in English)》2023,62(12):e202210823
To achieve a sustainable circular economy, polymer production must start transitioning to recycled and biobased feedstock and accomplish CO2 emission neutrality. This is not only true for structural polymers, such as in packaging or engineering applications, but also for functional polymers in liquid formulations, such as adhesives, lubricants, thickeners or dispersants. At their end of life, polymers must be either collected and recycled via a technical pathway, or be biodegradable if they are not collectable. Advances in polymer chemistry and applications, aided by computational material science, open the way to addressing these issues comprehensively by designing for recyclability and biodegradability. This Review explores how scientific progress, together with emerging regulatory frameworks, societal expectations and economic boundary conditions, paint pathways for the transformation towards a circular economy of polymers. 相似文献
406.
Hannah F. Mathews Maria I. Pieper Dr. Se-Hyeong Jung Prof. Andrij Pich 《Angewandte Chemie (International ed. in English)》2023,62(36):e202304908
In pH-responsive drug carriers, the distribution of charges has been proven to affect delivery efficiency but is difficult to control and verify. Herein, we fabricate polyampholyte nanogel-in-microgel colloids (NiM−C) and show that the arrangement of the nanogels (NG) can easily be manipulated by adapting synthesis conditions. Positively and negatively charged pH-responsive NG are synthesized by precipitation polymerization and labelled with different fluorescent dyes. The obtained NG are integrated into microgel (MG) networks by subsequent inverse emulsion polymerization in droplet-based microfluidics. By confocal laser scanning microscopy (CLSM), we verify that depending on NG concentration, pH value and ionic strength, NiM−C with different NG arrangements are obtained, including Janus-like phase-separation of NG, statistical distribution of NG, and core–shell arrangements. Our approach is a major step towards uptake and release of oppositely charged (drug) molecules. 相似文献