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Modular Framework for 3D Molecular Generation in Computational Chemistry Applications

Poisoning‐Resistant Complete Hydrogenation of Liquid Organic Hydrogen Carriers Over Ni‐Based Inverse Catalysts

ABSTRACT Efficient hydrogen storage using liquid organic hydrogen carriers (LOHCs) requires catalysts that combine high low‐temperature activity with robustness against impure H 2 feeds. Conventional supported Ni catalysts are hindered by strong substrate adsorption and consequent site poisoning. Herein, a Ni based inverse catalyst consisting of CeZrO x clusters supported on metallic Ni is designed, which achieves >99.9% yield in the complete hydrogenation of diverse LOHCs—including mono‐, bi‐, and triphenyl‐type N‐heterocyclic and purely aromatic substrates—at low‐temperature of 130°C, exhibiting a 200‐fold higher activity than conventional Ni catalysts. Key to this performance is the oxide‐induced polarization of Ni atoms (Ni δ+ ), creating a thermodynamic stable subsurface reservoir and migration routes for dissociated H* species. Through this hydrogen transport pathway, hydrogen can efficiently hydrogenate the strongly adsorbed LOHCs. The significantly lowered H 2 kinetic order confirms the increased surface H* coverage in this inverse configuration. Decoupling the strong substrate adsorption sites and hydrogenation sites, the inverse configuration prevents self‐poisoning, enabling complete hydrogenation using crude H 2 and solvent‐free LOHCs. This work highlights the superior substrate generality and complete‐hydrogenation capability of the Ni inverse catalyst, establishing such inverse systems as a versatile platform for mild and robust LOHC‐based hydrogen storage.

Gradient-guided layerwise adaptive noise injection for pre-trained language model fine-tuning

Direct Photoredox Synthesis of <i>N</i> -Linked Glycoproteins

Asymmetric α‐Alkylation With Activated and Unactivated Electrophiles by a Highly Productive and Recyclable Lewis Acid/Imidazolium Catalyst

ABSTRACT Asymmetric alkylation is widely used for the construction of α‐stereogenic carbonyl compounds, yet existing catalytic protocols typically suffer from several issues: (1) a limitation to π‐activated electrophiles, (2) the need for unsatisfying catalyst loadings, (3) a lack of catalyst recyclability, and (4) sophisticated catalyst structures requiring multi‐step syntheses. Herein, an efficiently accessible, air‐stable bifunctional Cu(II)/imidazolium catalyst (prepared over four steps without chromatographies in 74% yield) is reported that enables highly enantioselective α‐alkylations of 1,3‐dicarbonyls with unmet productivity (TON up to 1740). The catalyst exhibits broad electrophile compatibility, efficiently engaging π‐activated and non‐π‐activated alkylation agents. Remarkably, stereoretentive allylation with ( E )‐ and ( Z )‐configured allylbromides was achieved. The catalyst can be recycled over multiple cycles (10+) without loss of efficiency by a simple protocol. EPR proves formation of a Cu(II)‐enolate as resting state, for which detailed DFT calculations show that it is structurally anchored by hydrogen‐bonding to the imidazolium C(2) H . This feature is essential for stereodifferentiation of both enolate faces. A continuous mechanistic shift from S N 1‐like to S N 2‐type pathways is likely, depending on the electronic properties of the electrophile. This new alkylation concept allows for high practicality, combined with broad applicability and might serve as design prototype for future alkylation catalysts.

Nanometer scale imaging to develop quantitative descriptors of bipolar membrane junction structure

Abstract Swings in pH can be achieved by electrically polarizing a bipolar membrane (BPM) to drive water dissociation at the BPM junction for electrochemical conversion and separation processes. BPM junction design is critical to tailor performance for specific applications; however, characterization techniques capable of resolving the nanometer scale physical structure of the junction are limited. We present sample preparation, imaging, and analysis workflows that are adaptable to a variety of BPM junction architectures. Atomic force microscopy produces BPM junction images with nanometer scale lateral resolution for samples with and without a graphene oxide water dissociation catalyst in the junction. Subsequent image segmentation and analysis quantify line edge roughness and catalyst layer thickness as descriptors of junction structure. Comparison of pre- and post-electrodialysis junctions suggests electric field-induced alignment of catalyst particles during electrodialysis. This characterization workflow can inform manufacturing protocols, computational modeling, and failure mode analysis for next-generation BPMs.

Influence of root inducers and substrates on the vegetative propagation of pitahaya species (Hylocereus spp.) under nursery conditions

Pd-Catalyzed Arylative Lossen Rearrangement: Synthesis of Secondary Amines from Aryl/Alkyl Carboxylic Acids and Aryl Halides

Electron‐Localized RuNi Nanosheet Assemblies Enable Low‐Overpotential Mg‐CO ₂ Battery

ABSTRACT Mg‐CO 2 battery is emerging as a promising energy storage system that simultaneously converts CO 2 into value‐added products. However, its practical application is hindered by formation thermodynamically stable and electrically insulating discharge product MgCO 3 , which severely limits energy efficiency of Mg‐CO 2 battery. Herein, we report an electron‐localized Ru 61 Ni 39 nanosheet assembly catalyst that overcomes these limitations by precisely engineering the surface electronic structure for achieving precise tuning of product from MgCO 3 to MgC 2 O 4 of Mg‐CO 2 battery. We demonstrate that electron transfer from Ni to Ru creates the localized electron at the Ru sites, weakening MgC 2 O 4 binding and suppressing its conversion to MgCO 3 , thereby enabling reversible formation and decomposition of MgC 2 O 4 and mitigating cathode passivation. The Mg‐CO 2 battery incorporating the electron‐localized Ru 61 Ni 39 nanosheet assembly catalyst achieves an ultralow charge overpotential of 0.07 V and a record‐high energy conversion efficiency of 94.1%, with the stable cycling for over 580 h. In situ electrochemical spectroscopy and theoretical studies reveal that the electron‐localized between Ru and Ni stabilizes the product intermediates (C 2 O 4 2− ) and prevents the MgC 2 O 4 conversion to MgCO 3 .

Brain-structural differences underlying dialect competence in the bilingual network

Abstract Research in multilingualism has provided evidence for brain structural differences between monolinguals and bilinguals. Less is known about speakers who, apart from a standard language, also show competence in a variety (dialect) of this language (“bidialectals”). In these populations, cultural differences are minimized and language competence can be compared against a common ground. We hypothesize that bidialectals show brain-structural differences to non-bidialectals, and capitalize on one of the world’s largest dialect corpus available for German. A competent dialect group (N = 26) and a group without dialect competence (N = 23) were compared by using brain structural measures, including gray matter volume (GMV) and cortical thickness (CT). Results demonstrate a whole-brain group difference, seen for CT in right orbitofrontal cortex, and for GMV in bilateral middle temporal gyrus and bilateral insula. Notably, CT in right fusiform cortex as well as GMV in bilateral middle temporal gyrus and right insula co-varied with dialect competence differently for the two groups. The structural differences and covariations with dialect competence are discussed on the background of code switching and language control. The findings suggest that dialect competence may shape brain structure in ways similar to bilingualism.

Proteolysis‐Assisted Cyclization Facilitates Site‐Centric Target Deconvolution of Isothiocyanates

ABSTRACT Isothiocyanates (ITCs) are a unique class of electrophilic natural products that exert biological effects by reacting with proteinous cysteines to generate thionoacyl adducts. However, the identification of ITCs’ target sites is still an unmet task due to the high lability of such adducts. Here, we report an unexpected chemistry through which the ITC‐protein adduct forms a stable N‐terminal dihydrothiazole peptide adduct during proteolysis. This proteolysis‐assisted cyclization (PAC) reaction can be harnessed for developing affinity‐based and activity‐based chemoproteomic methods to site‐specifically profile targets of ITCs. Applying these methods not only adds further complexity to the known polypharmacological landscape of sulforaphane but also expands the ligandable cysteinome with site‐level resolution through a 55‐member ITC library. Given the promising chemopreventive and therapeutic effects of ITCs, the PAC‐based chemoproteomic platform may lay the groundwork for elucidating their mechanisms of action and ultimately diversifying cysteine targetability for drug discovery.

Allelopathic effects of Padina sp. and Sargassum sp. as biological control agents of harmful algal blooms (HABs) in the Persian Gulf and Gulf of Oman

Togetherness: How cooperation built the world

Threading an Aluminum Molecular Ring Onto a Chemically Growing Copper‐Directed Polyrotaxane

ABSTRACT Controlled assembly of advanced mechanically interlocked architectures remains a major challenge in supramolecular chemistry. Inspired by the hard and soft acids and bases principle, we present a modular and hierarchical strategy for the synthesis of aluminum‐based mechanically interlocked molecules (AlMIMs) assembled from four synergistic components. Aluminum ions generate robust macrocyclic frameworks through coordination with aromatic carboxylates, while adaptive nitrogen‐donor ligands, in concert with structure‐directing copper ions, promote axle threading and govern structural dimensionality. This approach creates a full structural library, from discrete [2]‐ and [3]rotaxanes to extended polyrotaxane networks, demonstrating broad versatility. Within the spatially confined macrocyclic cavity, copper ions preferentially adopt a stable linear coordination geometry while remaining conformationally flexible outside the cavity to accommodate diverse coordination modes and aggregation states. This dual behavior cooperatively facilitates highly ordered assembly. Notably, the resulting AlMIMs exhibit remarkably enhanced third‐order nonlinear optical responses, highlighting emergent properties arising from mechanical interlocking. This work underscores the power of merging coordination chemistry with supramolecular design, transcending conventional static paradigms by revealing how metal ion coordination can be dynamically modulated within precisely engineered supramolecular environments.

Attention augmented feature fusion in a hybrid CNN–transformer for fine-grained diabetic retinopathy severity grading

Surface-Immobilized Rhodium Complex in Vertically Aligned Mesoporous Silica Films for Direct Electroreduction of Diluted CO ₂

Highly Selective On‐Surface Synthesis of sp ² /sp‐Hybridized Heterochiral Triangular Nanorings

ABSTRACT A central challenge in on‐surface synthesis of topologically unique carbon nanostructures lies in the precise and selective construction of triangular nanorings. Achieving the resulting chirality and the sp 2 /sp‐hybridized state simultaneously from prochiral precursors is critical, yet immensely difficult. Here, we design an asymmetric α‑cyanostilbene derivative with aggregation‑induced emission properties as a prochiral building block to achieve deterministic pathway selection through controlling the substrate‐ and thermal‐directed strategy, allowing for the targeted formation of heterochiral nanorings with defined sp 2 ‐ and sp‐hybridization on Ag(111). Direct thermal deposition onto a hot Ag(111) surface at 443 K drives a highly selective cyclotrimerization, yielding discrete sp 2 ‐hybridized heterochiral triangular nanorings. Subsequent annealing induces an elimination reaction, converting these rings into their sp‐hybridized analogues while preserving chirality. In contrast, room‐temperature deposition and postannealing predominantly produces linear chains. The structural evolution and selective reaction mechanisms are unequivocally characterized by scanning tunneling microscopy (STM), bond‐resolution STM, synchrotron radiation photoemission spectroscopy (SRPES), and density functional theory (DFT) calculations. This work establishes a novel strategy for the precise synthesis of chiral triangular nanorings, revealing the critical role of surface‐mediated conformational control and dynamic covalent bonding in determining product topology and chirality.

Self-compassion and earthquake fear: the mediating roles of resilience and fear of happiness

Effective Vacancy Regulation Simultaneously Realizes High-Performance Thermoelectric Cooling and Power Generation in n-Type PbSe Crystals

An empirical study of defect clustering in deep neural networks and its implications for testing