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Nowadays, conjugated microporous polymers (CMPs) of the donor‐acceptor (D‐A) type show excellent photocatalytic performance in water splitting due to their efficient isolation of light‐induced excitons. The key to this activity lies in the appropriate selection of electron donor and acceptor units. In this paper, we synthesized three D‐A carbazole‐based CMPs and investigated the influence of planarity, electronic structure, crystallinity, and surface area on their photocatalytic efficiency in hydrogen evolution from water. Our CMPs have excellent light collection ability, fast separation rates, and minimal recombination rates for the electron/hole pairs, so an excellent hydrogen evolution rate (HER) was achieved by water reduction. Moreover, the most efficient semiconductor Cz‐4Py CMP, which had the lowest dihedral angle, more suitable LUMO level, semi‐crystalline nature, and largest surface area, showed the best HER up to 8813 μmol g−1 h−1 under visible light with an apparent quantum yield (AQY) of 4.51 % at λ=420 nm. While the HERs for Cz‐4TPT and Cz‐4TzTz CMPs with higher dihedral angle, amorphous nature, and lower surface area were 1702 and 1541 μmol g−1 h−1, respectively. The efficiencies obtained exceed those of many polymeric materials reported for photocatalytic H2O reduction. This work confirms the importance of the molecular design of CMP photocatalysts to optimize their performance in hydrogen release by water dissociation. [ABSTRACT FROM AUTHOR]

Solid oxide cell electrodes need to display a wide range of combined properties, for example, electronic and ionic conductivities, catalytic activity, chemical compatibility with other parts, thermal expansion match, phase stability, and tolerance to foreign species/contaminants. It is extremely challenging for a single material to meet all these features required. Surface decoration is a remarkably adaptive strategy to provide needed features to the electrodes by introducing functioning materials through various target‐guided methods. This review provides an overview of typical and novel techniques to create surface decoration on the electrodes to abruptly improve the drawbacks of the electrodes of solid oxide cells, including performance enhancement, stability of long‐term operation, and tolerance to poisoning foreign species. It starts with the introduction of surface decoration experimental procedure, proceeds to crucial characterization methods that are particularly effective in identifying the properties of the surface coating, continues with target‐oriented practice in terms of surface decoration materials choice and microstructure manipulation, and ends with the explorations of functioning mechanisms for the resultant behavior. With hope, the review will spark more novel utilizations of surface decoration practice to promote the technical status of the solid oxide cells for widespread commercialization in the future. [ABSTRACT FROM AUTHOR]

CONTEXT: Since civil unrest broke out in Somalia in the 1990s, large numbers of Somalis have immigrated to Western countries, including the United States. It is unknown whether these immigrants maintain their cultural norms of low contraceptive use and high fertility when they live in settings with different norms. METHODS: In 2016, interviews were conducted in Minnesota with Somali immigrants and refugees to explore couple communication and decision making regarding child spacing. Nineteen married men and women aged 25–51 were interviewed. After a coding scheme was developed, key themes were identified and examined by participants' sex, number of children and age of arrival in the United States. RESULTS: Most participants discussed child spacing with their spouse and had positive or neutral experiences. Some participants, especially those with multiple children, stated that living in their new country had influenced their fertility desires. Only those who had arrived after the age of 20 mentioned that experiencing closely spaced births had motivated them to discuss child spacing. Participants emphasized the importance of information sharing, compromise and joint decision making with their spouse. Priority for child‐spacing decision making was granted to women, largely because of their primary role in childbirth. Men who had arrived in the United States before turning 20 were more definitive about giving women decision‐making priority. CONCLUSIONS: These findings provide insight into how Somali immigrant and refugee couples communicate and make decisions about child spacing, and may be helpful in informing the development of culturally specific reproductive health programs. [ABSTRACT FROM AUTHOR]