Ship-source greenhouse gas (GHG) emissions could increase by up to 250% by 2050 from their 2012 levels, owing to increasing global freight volumes. Binding international legal agreements to regulate GHGs, however, are lacking as technical solutions remain expensive, and crucial industrial support is absent. In 2003, the International Maritime Organization adopted Resolution A.963 (23) to regulate shipping CO emissions via technical, operational, and market-based routes. However, progress has been slow and uncertain; there is no concrete emission reduction target or definitive action plan. Yet, a full-fledged roadmap may not even emerge until 2023. In this policy analysis, we revisit the progress of technical, operational, and market-based routes and the associated controversies. We argue that 1) a performance-based index, though good-intentioned, has loopholes affecting meaningful CO emission reductions driven by technical advancements; 2) using slow steaming to cut energy consumption stands out among all operational solutions thanks to its immediate and obvious results, but with the already slow speed in practice, this single source has limited emission reduction potential; 3) without a technology-savvy shipping industry, a market-based approach is essentially needed to address the environmental impact. To give shipping a 50:50 chance for contributing fairly and proportionately to keep global warming below 2°C, deep emission reductions should occur soon.

This article reports the fabrication of hybrid silica nanoparticles using surface-initiated atom transfer radical polymerization (SI-ATRP) technique. The surface of silica nanoparticles were densely grafted with 2-(dimethylamino) ethyl methacrylate (DMAEMA) and then quaternized with 1-bromohexane via two methods. FTIR, 1 H NMR, XPS, SEM, TGA, and GPC were used to determine the chemical structure, morphology, and other properties of the products. SEM images of nanocomposites showed spherical shaped morphology with an average diameter of ∼50 nm and they were direct evidences that the hybrid silica nanoparticles had uniform core-shell morphology. Evolution of GPC traces of grafted polyDMAEMA showed that the SI-ATRP could be conducted in a well-controlled manner.

Konjac glucomannan (KGM) is recognized as a safe material for its health-promoting benefits and thus widely used in various fields including pharmaceutical industry. In recent decades, the combination of collagen and KGM attracts more attentions for biomedical purpose, especially the hybrid films of collagen–KGM or collagen–KGM–polysaccharide. In this study, to further and deeply develop the intrinsic values of both collagen and KGM as biomaterials, a novel kind of composite hydrogel comprising collagen and KGM at a certain ratio was fabricated under mild conditions via fibrillogenesis process of the aqueous blends of collagen and KGM that experienced deacetylation simultaneously. The chemical composition, microcosmic architectures, swelling behavior, biodegradation and dynamic mechanic properties of such resulted composite hydrogels were systematically investigated. Biologic experiments, including cell culture in vitro and hypodermic implantation in vivo, were also conducted on these collagen/KGM composite hydrogels to evaluate their biologic performances. The relevant results prove that, based on collagen self-assembly behavior, this synthesis strategy is efficient to construct a composite hydrogel of collagen/KGM with improved mechanical properties, biodegradability, excellent biocompatibility and bioactivity, which are promising for potential biomedical applications such as tissue engineering and regenerative medicine.

Defect engineering has become an effective way to improve the surface performance of nanoelectrochemical catalysts. In this article, the ultrathin defect-rich Co(OH) 2 nanosheet arrays in situ grew on carbon cloth (U-D-Co(OH) 2 NSA/CC), which was synthesized by etching a metal−organic framework at room temperature. The physical and chemical properties of the obtained U-D-Co(OH) 2 NSA were characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. It is an efficient electrode for detecting glucose and formaldehyde under alkaline conditions. As a glucose and formaldehyde sensor, it exhibited superior electrocatalytic activity, for instance, shorter response time (<5 s), limit of detection (LOD) of 0.32 μM and 0.57 μM (S/N = 3), and response sensitivity of 6759.0 μA mM −1 cm −2 for glucose and 2444.0 μA mM −1 cm −2 for formaldehyde with outstanding reproducibility and selectivity, respectively.

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