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551.
The evolutionary development of the hominids that culminated in the appearance of Homo sapiens included the subdivision of the species into societies on the basis of culturally, instead of biologically, constructed differentiation. It is argued that this change must have occurred after the mental ability to formulate and culturally express conceptual structures of extended relationships had been been biologically introduced, and that intergroup competition within a species provided the selective impetus for this more complex form of organization. The combination of conceptual structures for organization at a more extensive scale and the effects of intergroup competition would lead to a restructuring of the whole species into society like groups. 相似文献
552.
R. S. Hughesdon G. J. Robertson J. Read G. Tammann K. L. Dreyer M. Bodenstein H. Mainz J. Corbière W. Krings und H. Salmang 《Fresenius' Journal of Analytical Chemistry》1931,84(6-7):248-253
Ohne Zusammenfassung 相似文献
553.
554.
Julian Kund Jan-Hendrik Kruse Andreas Gruber Dr. Ivan Trentin Marcel Langer Dr. Clarissa Read Dr. Gregor Neusser Dominik Blaimer Dr. Ulrich Rupp Prof. Dr. Carsten Streb Prof. Dr. Kerstin Leopold Prof. Dr. Felix H. Schacher Prof. Dr. Christine Kranz 《Angewandte Chemie (International ed. in English)》2023,62(22):e202217196
Heterogeneous light-driven catalysis is a cornerstone of sustainable energy conversion. Most catalytic studies focus on bulk analyses of the hydrogen and oxygen evolved, which impede the correlation of matrix heterogeneities, molecular features, and bulk reactivity. Here, we report studies of a heterogenized catalyst/photosensitizer system using a polyoxometalate water oxidation catalyst and a model, molecular photosensitizer that were co-immobilized within a nanoporous block copolymer membrane. Via operando scanning electrochemical microscopy (SECM), light-induced oxygen evolution was determined using sodium peroxodisulfate (Na2S2O8) as sacrificial electron acceptor. Ex situ element analyses provided spatially resolved information on the local concentration and distribution of the molecular components. Infrared attenuated total reflection (IR-ATR) studies of the modified membranes showed no degradation of the water oxidation catalyst under the reported light-driven conditions. 相似文献
555.
Jesus Guillen Campos Friedrich Stricker Kyle D. Clark Minwook Park Sophia J. Bailey Alexa S. Kuenstler Ryan C. Hayward Javier Read de Alaniz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214339
Aligned liquid crystal polymers are materials of interest for electronic, optic, biological and soft robotic applications. The manufacturing and processing of these materials have been widely explored with mechanical alignment establishing itself as a preferred method due to its ease of use and widespread applicability. However, the fundamental chemistry behind the required two-step polymerization for mechanical alignment has limitations in both fabrication and substrate compatibility. In this work we introduce a new protection-deprotection approach utilizing a two-stage Diels–Alder cyclopentadiene-maleimide step-growth polymerization to enable mild yet efficient, fast, controlled, reproducible and user-friendly polymerizations, broadening the scope of liquid crystal systems. Thorough characterization of the films by DSC, DMA, POM and WAXD show the successful synthesis of a uniaxially aligned liquid crystal network with thermomechanical actuation abilities. 相似文献