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The state of progress towards climate adaptation is currently unclear. Here we apply a structured expert judgement to assess multiple dimensions shaping adaptation (equally weighted): risk knowledge, planning, action, capacities, evidence on risk reduction, long-term pathway strategies. We apply this approach to 61 local coastal case studies clustered into four urban and rural archetypes to develop a locally informed perspective on the state of global coastal adaptation. We show with medium confidence that today’s global coastal adaptation is halfway to the full adaptation potential. Urban archetypes generally score higher than rural ones (with a wide spread of local situations), adaptation efforts are unbalanced across the assessment dimensions and strategizing for long-term pathways remains limited. The results provide a multi-dimensional and locally grounded assessment of global coastal adaptation and lay new foundations for international climate negotiations by showing that there is room to refine global adaptation targets and identify priorities transcending development levels.

Proton-exchange membrane fuel cells enable the portable utilization of hydrogen (H2) as an energy resource. Current electrolytic materials have limitation, and there is an urgent need to develop new materials showing especially high proton conductivity. Here, we report the ultra-fast proton conduction in a novel metal–organic framework, MFM-808, which adopts an unprecedented topology and a unique structure consisting of two-dimensional layers of {Zr6}-clusters. By replacing the bridging formate with sulfate ligands within {Zr6}-layers, the modified MFM-808-SO4exhibits an exceptional proton conductivity of 0.21 S·cm–1at 85 °C and 99% relative humidity. Modeling by molecular dynamics confirms that proton transfer is promoted by an efficient two-dimensional conducting network assembled by sulfate–{Zr6}-layers. MFM-808-SO4also possesses excellent photocatalytic activity for water splitting to produce H2, paving a new pathway to achieve a renewable hydrogen-energy cycle.

ABSTRACT Ladle furnace (white or basic) slag is a significant by-product of the steelmaking industry; nowadays the manufacturing process yields two types of basic slag that are either low or [...]

Carbene–metal–amides (CMAs) are an emerging class of photoemitters based on a linear donor–linker–acceptor arrangement. They exhibit high flexibility about the carbene–metal and metal–amide bonds, leading to a conformational freedom which has a strong influence on their photophysical properties. Herein we report CMA complexes with (1) nearly coplanar, (2) twisted, (3) tilted, and (4) tilt-twisted orientations between donor and acceptor ligands and illustrate the influence of preferred ground-state conformations on both the luminescence quantum yields and excited-state lifetimes. The performance is found to be optimum for structures with partially twisted and/or tilted conformations, resulting in radiative rates exceeding 1 × 106s–1. Although the metal atoms make only small contributions to HOMOs and LUMOs, they provide sufficient spin–orbit coupling between the low-lying excited states to reduce the excited-state lifetimes down to 500 ns. At the same time, high photoluminescence quantum yields are maintained for a strongly tilted emitter in a host matrix. Proof-of-concept organic light-emitting diodes (OLEDs) based on these new emitter designs were fabricated, with a maximum external quantum efficiency (EQE) of 19.1% with low device roll-off efficiency. Transient electroluminescence studies indicate that molecular design concepts for new CMA emitters can be successfully translated into the OLED device.

Abstract A high performance concrete, known as polymer concrete, made up of natural aggregates and an orthophthalic polyester binder, reinforced with non-metallic bars (glass reinforced polymer) has been studied. The [...]

Four 3d–4f hetero-polymetallic complexes [Fe2Ln2((OCH2)3CR)2(O2CtBu)6(H2O)4] (where Ln = La (1and 2) and Gd (3and 4); and R = Me (1and 3) and Et (2and 4)) are synthesized and analyzed using elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and SQUID magnetometry. Crystal structures are obtained for both methyl derivatives and show that the complexes are isostructural and adopt a defective dicubane topology. The four heavy metals are connected with two alkoxide bridges. These four precursors are used as single-source precursors to prepare rare-earth orthoferrite pervoskites of the form LnFeO3. Thermal decomposition in a ceramic boat in a tube furnace gives orthorhombic LnFeO3powders using optimized temperatures and decomposition times: LaFeO3formed at 650 °C over 30 min, whereas GdFeO3formed at 750 °C over 18 h. These materials are structurally characterized using powder X-ray diffraction, Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray map spectroscopy, and SQUID magnetometry. EDX spectroscopy mapping reveals a homogeneous spatial distribution of elements for all four materials consistent with LnFeO3. Magnetic measurements on complexes 1–4confirm the presence of weak antiferromagnetic coupling between the central Fe(III) ions of the clusters and negligible ferromagnetic interaction with peripheral Gd(III) ions in 3and 4. Zero-field-cooled and field-cooled measurements of magnetization of LaFeO3and GdFeO3in the solid-state suggest that both materials are ferromagnetic, and both materials show open magnetic hysteresis loops at 5 and 300 K, with Msathigher than previously reported for these nanomaterials. We conclude that this is a new and facile low temperature route to these important magnetic materials that is potentially universal, limited only by what metals can be programmed into the precursor complexes.

The synthesis, structures, and properties of [4]- and [3]-rotaxane complexes are reported where [2]-rotaxanes, formed from heterometallic {Cr7Ni} rings, are bound to a fluoride-centered {CrNi2} triangle. The compounds have been characterized by single-crystal X-ray diffraction and have the formulas [CrNi2(F)(O2CtBu)6]{(BH)[Cr7NiF8(O2CtBu)16]}3(3) and [CrNi2(F)(O2CtBu)6(THF)]{(BH)[Cr7NiF8(O2CtBu)16]}2(4), where B= py-CH2CH2NHCH2C6H4SCH3. The [4]-rotaxane 3is an isosceles triangle of three [2]-rotaxanes bound to the central triangle while the [3]-rotaxane 4contains only two [2]-rotaxanes bound to the central triangle. Studies of the behavior of 3and 4in solution by small-angle X-ray scattering and atomistic molecular dynamic simulations show that the structure of 3is similar to that found in the crystal but that 4has a different conformation to the crystal. Continuous wave and pulsed electron paramagnetic resonance spectroscopy was used to study the structures present and demonstrate that in frozen solutions (at 5 K) 4forms more extended molecules than 3and with a wider range of conformations.

We use a numerical model, already validated for this purpose, to simulate the effect of wave frequency spread on wave transformation and swash amplitudes. Simulations are performed for planar beach slope cases and for offshore wave spectra whose frequency spread changes over realistic values. Results indicate that frequency spread, under normally approaching waves, affects swash amplitudes. For moderately dissipative conditions, the significant infragravity swash increases for increasing values of the offshore frequency spread. The opposite occurs under extremely dissipative conditions. The numerical analysis suggests that this inverted pattern is driven by the effect that different distributions of incoming long‐wave energy have on low‐frequency wave propagation and dissipation. In fact, with large frequency spreads, wave groups force relatively short subharmonic waves that are strongly enhanced in the shoaling zone. This process leads to an infragravity swash increase for increasing frequency spread under moderately dissipative conditions in which low‐frequency energy dissipation in shallow water is negligible or small. However, under extremely dissipative conditions, the significant low‐frequency energy dissipation associated with large frequency spreads overturns the strong energy growth in the shoaling zone eventually yielding an infragravity swash decrease for increasing frequency spread. Numerical simulations reveal that frequency spread affects swash amplitudes with a pattern that inverts over two Iribarren number rangesAn infragravity swash increase for increasing frequency spread is observed under moderately dissipative conditionsThe infragravity swash increases for decreasing frequency spread under extremely dissipative conditions

The first fully characterized boron-functionalized heptaphosphide Zintl cluster, [(BBN)P7]2–([1]2–), is synthesized by dehydrocoupling [HP7]2–. Dehydrocoupling is a previously unprecedented reaction pathway to functionalize Zintl clusters. [Na(18-c-6)]2[1] was employed as a transition metal-free catalyst for the hydroboration of aldehydes and ketones. Moreover, the greenhouse gas carbon dioxide (CO2) was efficiently and selectively reduced to methoxyborane. This work represents the first examples of Zintl catalysis where the transformation is transition metal-free and where the cluster is noninnocent.

Addition of (1-phenyl)ethenyl-amines H 2C=C(NR 2)Ph 2a,bto (1-alkynyl)carbene complexes (CO) 5M=C(OEt)C≡CPh 1a,b(M= W, Cr) affords 1-metalla-1,3,5-hexatrienes 4a-cin 90 –95%. Addition of N-[1-(cyclohex-1-enyl)]ethenyl-amines H 2)-(∼)C= CH(CH 2) 4∼ 2c,dto compounds 1a,byields novel 1-metalla-1,3,5,7 -octatetraenes (CO) 5M=C(OEt)-CH=C(Ph)-CH=C(NR-(∼)C=CH (CH 4d-fas major products together with a [4+2] cycloadduct 5das minor product. Compounds 4and 5have been fully characterized spectroscopically, compound 4dalso by X-ray analysis.