News from Science China Press

By regulating coordination angles of two carbazole-pyridine ligands (L1, L2) and building blocks (E1(OTf)₂, E2(OTf)₂), successfully obtained four architectures: a molecular-tweezer-like compound, a snowflake-shaped fold assembly, an 8₁₈ knot, and a closed three-link chain. SC-XRD validated the structures and showed that the ligand angle determines whether the assembly is interlocked or folded. NMR and ESI-TOF-MS verified solution-phase formation and purity. Furthermore, the closed three-link chain exhibits high photothermal conversion performance. Its efficiency is directly influenced by π–π stacking interactions, and EPR experiments further confirm that the radical character of the building blocks also contributes to the photothermal properties.

A research team led by Professor Kaicun Wang at Peking University has released a homogenized gridded climate dataset for China (HCD01), providing daily, 0.1-degree climate data for 1961-2022. The dataset corrects non-climatic signals in long-term observations and merges homogenized station records with ERA5-Land reanalysis, offering a high-quality data basis for studying climate change and its impacts across China.

Researchers have developed a membrane-based strategy that separates complex light naphtha into valuable chemical streams at the molecular level. By mildly etching a metal–organic framework membrane with tannic acid, the team created complementary membranes that sort hydrocarbons by size and chemical affinity. The membrane cascade separated a 15-component petroleum mixture into three product streams while potentially reducing energy consumption by about 91% compared with conventional distillation.

In a paper published in SCIENCE CHINA Earth Sciences, researchers assessed the parameterization of orographic gravity wave drag (OGWD) in 3-km-resolution WRF simulations for precipitation forecast over the highly complex-terrain Southwest China. Their results reveal that OGWD parameterization, previously considered negligible in kilometer-scale models, can greatly improve the predicted rainfall intensity and location by modulating the low-level winds and moisture transport. These findings lay an important scientific foundation for operational precipitation forecasting in regions of complex terrain.

A study published online in Science Bulletin introduces structural connectome embeddedness, a state-level dimension describing how deeply each momentary whole-brain activity pattern is embedded in the topology of anatomical connections. Evidence from whole-brain biophysical modeling, macroscale functional organization patterns, and multimodal imaging in 713 Human Connectome Project participants supports the concept's biophysical grounding and prevalence. High-CoDE moments help anchor stable functional connectivity, individual variability relates to a behavioral dimension associated with mental health and clinical vulnerability, and task-evoked embeddedness increases with cognitive demand. The framework helps explain how a stable connectome organizes flexible brain activity.

A unified scaling analysis gives quantum geometry and disorder their own measurable weight patterns, allowing researchers to separate competing sources of the second-order nonlinear Hall effect in existing experiments.

Organic field-effect transistors (OFETs) are fundamental building blocks for flexible electronics, including flexible displays, wearable sensors and electronic skin. However, at the heterointerface between the organic semiconductor (OSC) and the dielectric layer where charge transport takes place, structural and energetic disorders inevitably introduce defects, which adversely affect device stability. To address these challenges, researchers from Tianjin University and collaborating institutions have developed a novel interfacial engineering strategy, in which ultrathin alkyl chains of alkylated OSC molecules are covalently attached to the OSC backbone. This approach effectively reduces the trap density at the OSC/dielectric interface, thereby enabling stable OFET operation. In addition, this strategy substantially decreases the dielectric layer thickness, which facilitates low‑voltage operation. As a result, OFETs constructed on the basis of this strategy operate stably at a low voltage of −1 V for over 10,000 s, while integrated logic circuits achieve high gain, fast switching and robust stability. This work provides a new pathway toward high-reliability flexible electronics.