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1. Methane Hydration‐Shell Structure and Fragility

   https://doi.org/10.1002/anie.201809372  

   Wu, Xiangen; Lu, Wanjun; Streacker, Louis M.; Ashbaugh, Henry S.; Ben‐Amotz, Dor (October 2018, Angewandte Chemie International Edition)

   Abstract The influence of oily molecules on the structure of liquid water is a question of importance to biology and geology and many other fields. Previous experimental, theoretical, and simulation studies of methane in liquid water have reached widely conflicting conclusions regarding the structure of hydrophobic hydration‐shells. Herein we address this question by performing Raman hydration‐shell vibrational spectroscopic measurements of methane in liquid water from −10 °C to 300 °C (at 30 MPa, along a path that parallels the liquid‐vapor coexistence curve). We show that, near ambient temperatures, methane's hydration‐shell is slightly more tetrahedral than pure water. Moreover, the hydration‐shell undergoes a crossover to a more disordered structure above ca. 85 °C. Comparisons with the crossover temperature of aqueous methanol (and other alcohols) reveal the stabilizing influence of an alcohol OH head‐group on hydrophobic hydration‐shell fragility. 

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2. A developmental and energetic basis linking larval oyster shell formation to acidification sensitivity: LARVAL SHELL AND ACIDIFICATION

   https://doi.org/10.1002/grl.50449  

   Waldbusser, George G.; Brunner, Elizabeth L.; Haley, Brian A.; Hales, Burke; Langdon, Christopher J.; Prahl, Frederick G. (May 2013, Geophysical Research Letters)
3. Bimetallic core–shell nanocrystals: opportunities and challenges

   https://doi.org/10.1039/D3NH00098B  

   Wang, Chenxiao; Shi, Yifeng; Qin, Dong; Xia, Younan (August 2023, Nanoscale Horizons)

   We present an overview of the opportunities provided by bimetallic core–shell nanocrystals, followed by a discussion of the challenges and promising solutions regarding the elucidation of the true surface composition and its dynamics. 

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4. Growth and morphogenesis of the gastropod shell

   https://doi.org/10.1073/pnas.1816089116  

   Johnson, Adam B.; Fogel, Nina S.; Lambert, J. David (March 2019, Proceedings of the National Academy of Sciences)

   Gastropod shell morphologies are famously diverse but generally share a common geometry, the logarithmic coil. Variations on this morphology have been modeled mathematically and computationally but the developmental biology of shell morphogenesis remains poorly understood. Here we characterize the organization and growth patterns of the shell-secreting epithelium of the larval shell of the basket whelkTritia(also known asIlyanassa). Despite the larval shell’s relative simplicity, we find a surprisingly complex organization of the shell margin in terms of rows and zones of cells. We examined cell division patterns with EdU incorporation assays and found two growth zones within the shell margin. In the more anterior aperture growth zone, we find that inferred division angles are biased to lie parallel to the shell edge, and these divisions occur more on the margin’s left side. In the more posterior mantle epithelium growth zone, inferred divisions are significantly biased to the right, relative to the anterior–posterior axis. These growth zones, and the left–right asymmetries in cleavage patterns they display, can explain the major modes of shell morphogenesis at the level of cellular behavior. In a gastropod with a different coiling geometry,Planorbellasp., we find similar shell margin organization and growth zones asTritia, but different left–right asymmetries than we observed in the helically coiled shell ofTritia. These results indicate that differential growth patterns in the mantle edge epithelium contribute to shell shape in gastropod shells and identify cellular mechanisms that may vary to generate shell diversity in evolution. 

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5. Ultrathin-shell epitaxial Ag@Au core-shell nanowires for high-performance and chemically-stable electronic, optical, and mechanical devices

   https://doi.org/10.1007/s12274-021-3718-z  

   Zhu, Yangzhi; Kim, Sanggon; Ma, Xuezhi; Byrley, Peter; Yu, Ning; Liu, Qiushi; Sun, Xiaoming; Xu, Da; Peng, Sangshan; Hartel, Martin C.; et al (November 2021, Nano Research)

   Abstract Silver nanowires (AgNWs) hold great promise for applications in wearable electronics, flexible solar cells, chemical and biological sensors, photonic/plasmonic circuits, and scanning probe microscopy (SPM) due to their unique plasmonic, mechanical, and electronic properties. However, the lifetime, reliability, and operating conditions of AgNW-based devices are significantly restricted by their poor chemical stability, limiting their commercial potentials. Therefore, it is crucial to create a reliable oxidation barrier on AgNWs that provides long-term chemical stability to various optical, electrical, and mechanical devices while maintaining their high performance. Here we report a room-temperature solution-phase approach to grow an ultra-thin, epitaxial gold coating on AgNWs to effectively shield the Ag surface from environmental oxidation. The Ag@Au core-shell nanowires (Ag@Au NWs) remain stable in air for over six months, under elevated temperature and humidity (80 °C and 100% humidity) for twelve weeks, in physiological buffer solutions for three weeks, and can survive overnight treatment of an oxidative solution (2% H 2 O 2 ). The Ag@Au core-shell NWs demonstrated comparable performance as pristine AgNWs in various electronic, optical, and mechanical devices, such as transparent mesh electrodes, surface-enhanced Raman spectroscopy (SERS) substrates, plasmonic waveguides, plasmonic nanofocusing probes, and high-aspect-ratio, high-resolution atomic force microscopy (AFM) probes. These Au@Ag core-shell NWs offer a universal solution towards chemically-stable AgNW-based devices without compromising material property or device performance. 

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