Mechanical force redistributes reactivity through anisotropic, topology-dependent load transmission. Predicting which covalent bond in a complex molecule ruptures first under tension remains a central problem in mechanochemistry, biomaterials and chemically recyclable polymers. Bond dissociation energy is an incomplete proxy because it describes zero-force thermodynamic stability, whereas mechanochemical site selectivity is governed more directly by the peak force sustained along a prescribed loading path. Here we introduce covalent-bond peak force network (CBPFNet), a graph-attention model that predicts covalent-bond peak force (CBPForce) from relaxed molecular structures through a virtual-stretching workflow and avoids the hundreds of constrained geometry optimisations typically required for each candidate bond. In the CHON benchmark studied here, CBPFNet reproduces bond-ranking trends from density functional theory (DFT) and can be used for bond-level screening. Post hoc attribution analyses indicate that rupture selectivity depends on both bond identity and local stiffness contrast, with relatively rigid segments concentrating tensile stress on softer adjacent bonds. In oligopeptides, the model recovers the DFT weakest bond and highlights a serine-containing motif as a possible topology-dependent weak point under the same protocol. CBPFNet therefore extends screening beyond equilibrium bond stability toward bond-resolved peak-force ranking in sustainable polymer design and biomaterials.

Efficient photocatalytic H₂O₂ production is a sustainable alternative to the anthraquinone process, yet designing photocatalysts with both high activity and selectivity is extremely challenging. Covalent organic frameworks (COFs) offer modular architectures and tunable electronic structures, but precise electronic modulation for maximizing H2O2 photosynthesis is rarely attained. Here we report a series of naphthalimide-based donor–acceptor COFs with systematically engineered cores. Among them, NDI–B–COF (benzene core) delivers an outstanding H₂O₂ yield of 11,025 μmol g⁻¹ h⁻¹ (with sacrificial agent), far surpassing its nitrogen- and triazine-core analogs. This performance stems from synergistic effects of an extended in-plane conjugation and a reduced core polarity, which collectively enhance charge separation, directional carrier transport, and *OH intermediate formation, thereby lowering the barrier for two-electron water oxidation. These findings establish a clear structure–property–activity correlation and offer a general strategy for developing highly efficient metal-free photocatalysts.

A research team has mapped how four post-harvest processing methods reshape flavor precursors in Arabica coffee beans, showing that anaerobic fermentation—especially anaerobic fermentation dry processing—substantially increases key non-volatile metabolites linked to aroma, flavor, acidity, body, and balance.

A research team has identified a previously uncharacterized long non-coding RNA, lnc87821, that helps control how tea plants respond to salt and alkali stress by negatively regulating the stress-related gene CsJAZ2.