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We focus on a class of special representations over a type $\mathbb{D}$ quiver $Q_{D}$ with $n$ vertices and directional symmetry, namely, maximal almost pre-rigid representations. By using the equivariant theory of group actions, we give a geometric model for the category of finite dimensional representations over $Q_{D}$ via centrally-symmetric polygon $P(Q_{D})$ with a puncture, and show that the dimension of extension group between indecomposable representations can be interpreted as the crossing number on $P(Q_{D})$. Furthermore, we provide a geometric realization for maximal almost pre-rigid representations over $Q_{D}$. As applications, we prove that each maximal almost pre-rigid representation will determine two or four tilting objects over the path algebra $\Bbbk Q_{\overline{D}}$, where $Q_{\overline{D}}$ is a quiver obtained by adding $n-2$ new vertices and $n-2$ arrows to the quiver $Q_{D}$, and we obtain a representation-theoretic interpretation of the type-$\mathbb{B}$ Cambrian lattices.

Solar-driven interfacial steam generation for desalination has attracted broad attention. However, a significant challenge still remains for achieving a higher evaporation rate and high water quality, together with a cost-effective and easy-to-manufacture device to provide a feasible solar-driven steam generation system. In this study, a novel ultra-black paint, Black 3.0, serving as a perfect solar absorber is introduced into the hot-pressed melamine foam networks, allowing us to construct an ultra-black (99% absorptance in the solar region) and self-floating evaporation device. The high performing features of effective solar absorptance and salt-rejection capability contribute to a high-to-date evaporation rate of freshwater at 2.48 kg m-2 h-1 under one sun (1 kW m-2). This interfacial solar evaporator has a daily drinkable water yield of 2.8 kg m-2 even in cloudy winter weather and maintains stability in water with a wide range of acidity and alkalinity (pH 1~14). These features will enable the construction of a facilely fabricated, robust, highly-efficient, and cost-effective solar steam generation system for freshwater production.