A Registration Method Based on Ordered Point Clouds for Key Components of Trains.

Point cloud registration is pivotal across various applications, yet traditional methods rely on unordered point clouds, leading to significant challenges in terms of computational complexity and feature richness. These methods often use k-nearest neighbors (KNN) or neighborhood ball queries to access local neighborhood information, which is not only computationally intensive but also confines the analysis within the object's boundary, making it difficult to determine if points are precisely on the boundary using local features alone. This indicates a lack of sufficient local feature richness.

High-Efficiency Precision Polishing Using Fiber Brush-Shear-Thickening Fluid Composites.

Shear-thickening fluid (STF) is widely applied in various practical engineering fields due to its rheological properties of increased viscosity under load. We investigated the integration of STF with fiber brushes to prepare a novel composite material for polishing applications. The impact of composite material properties is studied in surface finish, specifically roughness and morphology, across flat and uneven surfaces.

Theoretical Investigation of Single-Atom Catalysts for Hydrogen Evolution Reaction Based on Two-Dimensional Tetragonal MoC.

Developing highly efficient and cost-competitive electrocatalysts for the hydrogen evolution reaction (HER), which can be applied to hydrogen production by water splitting, is of great significance in the future of the zero-carbon economy. Here, by means of first-principles calculations, we have scrutinized the HER catalytic capacity of single-atom catalysts (SACs) by embedding transition-metal atoms in the C and Mo vacancies of a tetragonal MoC slab, where the transition-metal atoms refer to Ti, V, Cr, Mn, Fe, Co, Ni and Cu. All the MoC-based SACs exhibit excellent electrical conductivity, which is favorable to charge transfer during HER.

Quantitatively Detecting Camellia Oil Products Adulterated by Rice Bran Oil and Corn Oil Using Raman Spectroscopy: A Comparative Study Between Models Utilizing Machine Learning Algorithms and Chemometric Algorithms.

The fast and accurate quantitative detection of camellia oil products is significant for multiple reasons. In this study, rice bran oil and corn oil, whose Raman spectra both hold great similarities with camellia oil, are blended with camellia oil, and the concentration of each composition is predicted by models with varying feature extraction methods and regression algorithms. Back propagation neural network (BPNN), which has been rarely investigated in previous work, is used to construct regression models, the performances of which are compared with models using random forest (RF) and partial least squares regression (PLSR).

Boosting Carrier Mobility in 2D Layered Perovskites for High-Performance UV Photodetector.

2D hybrid perovskites have attracted great interest due to their promising potential in photodetectors. The phase structure, dielectric, and excitonic properties in 2D perovskites play a pivotal role in the performance of the corresponding optoelectronic device. Here a lattice anchoring method is demonstrated to boost carrier mobility in 2D perovskites by tailoring large organic spacer cation layers.

Unusual Temperature-Dependent Photoluminescence Due to Competing Excited-State Energy Transfer in Rare Earth Double Perovskites.

Lead-free halide double perovskites (DPs) have become a research hotspot in the field of photoelectrons due to their unique optical properties and flexible compositional tuning. However, the luminescence of DPs exhibits thermal quenching at high temperatures, which severely affects their further application. Herein, we synthesized the rare earth Dy and transition metal Mn codoped CsNaYCl rare earth DPs and characterized the optical properties using temperature-dependent photoluminescence spectra and time-resolved photoluminescence decay profiles at different temperatures.

Computational insights into the aggregation mechanism of human calcitonin.

Human calcitonin (hCT) is a peptide hormone that regulates calcium homeostasis, but its abnormal aggregation can disrupt physiological functions and increase the risk of medullary thyroid carcinoma. To elucidate the mechanisms underlying hCT aggregation, we investigated the self-assembly dynamics of hCT segments (hCT, hCT, and hCT) and the folding and dimerization of full-length hCT through microsecond atomistic discrete molecular dynamics (DMD) simulations. Our results revealed that hCT and hCT predominantly existed as isolated monomers with transient small-sized oligomers, indicating weak aggregation tendencies.

Proton Accumulation Modulated Surface Potential in Proton Conducting Ceramics Revealed by Near-Ambient Pressure X-ray Photoelectron Spectroscopy.

Proton conducting electrochemical cells (PCECs) are efficient and clean intermediate-temperature energy conversion devices. The proton concentration across the PCECs is often nonuniform, and characterizing the distribution of proton concentration can help to locate the position of rate-limiting reactions. However, the determination of the local proton concentration under operating conditions remains challenging.

AgNPs/CuNPs/Bragg-PSi substrate subjected to thermal annealing in high-sensitivity detection on crystal violets and diphenyl phthalate.

This study has successfully prepared three kinds of surface enhanced raman scattering (SERS) substrates, namely AgNP/CuNPs/Bragg-PSi (porous silicon, PSi), AgNPs/CuNPs/PSi and AuNPs/CuNPs/Bragg-PSi by use of an anode electrochemical etching method and a dip plating method. Results show that: the AgNPs/CuNPs/Bragg-PSi substrate has optimal SERS performance and is capable of detecting the Raman spectrum ( = 0.9315) of a 10 M-10 M crystal violet (CV) solution.

Harnessing acylhydrazone-oxime exchange reaction to achieve diverse synthesis of glycosite-specific antibody-drug conjugates.

Glycosite-specific antibody-drug conjugates (gsADCs), which carry cytotoxic payloads at the conserved -glycosylation site, N297, of an IgG, have emerged as a promising ADC format with better therapeutic index. Conjugating the payloads aldehyde-based chemistry is more friendly to IgGs, and has been widely investigated. However, the efficiency of introducing an aldehyde tag at the N297 site is poor due to the complicated procedures required, such as the multiple-enzyme-catalyzed IgG glycoengineering process and the successive oxidation step, which always results in heterogeneous products and poor stability.

Dual-Phase Ligand Engineering Enables 18.21% FAPbI Quantum Dot Solar Cells.

Formamidinium lead triiodide (FAPbI) perovskite quantum dot (PQD) are promising candidate for high-performing quantum dot photovoltaic due to its narrow bandgap, high ambient stability, and long carrier lifetime. However, the carrier transport blockage and nonradiative recombination loss, originating from the high-dielectric ligands and defects/trap states on the FAPbI PQD surface, significantly limit the efficiency and stability of its photovoltaic performance. In this work, through exploring dual-site molecular ligands, namely 2-thiophenemethylammonium iodide (2-TM) and 2-thiopheneethylammonium iodide (2-TE), a dual-phase synergistic ligand exchange (DSLE) protocol consisting of both solution-phase and solid-state ligand engineering is demonstrated.

Evolution of Two-Dimensional Perovskite Films Under Atmospheric Exposure and Its Impact on Photovoltaic Performance.

Two-dimensional (2D) Ruddlesden-Popper perovskites (RPPs) have garnered significant attention due to their enhanced stability compared with their three-dimensional counterparts. However, the power conversion efficiency (PCE) of 2D perovskite solar cells (2D-PSCs) remains lower than that of 3D-PSCs. Understanding the microstructural evolution of 2D perovskite films during fabrication is essential for improving their performance.

Coordination Equilibrium-Assisted Coprecipitation Synthesis of Atomically Dispersed 3d Metal Catalysts.

As a frontier of heterogeneous catalysis, single-atom catalysts (SACs) have been extensively studied fundamentally. One obstacle that limits the industrial application of SACs is the lack of a synthetic method that can prepare the catalysts on a large scale. Wet-chemistry methods that are conventionally used to prepare nanoparticle-based industrial catalysts might be a solution.

Probing Berry Phase Effect in Topological Surface States.

We have observed the Berry phase effect associated with interband coherence in topological surface states (TSSs) using two-color high-harmonic spectroscopy. This Berry phase accumulates along the evolution path of strong field-driven electron-hole quasiparticles in electronic bands with strong spin-orbit coupling. By introducing a secondary weak field, we perturb the evolution of Dirac fermions in TSSs and thus provide access to the Berry phase.

Electride transition in liquid aluminum under high pressure and high temperature.

Despite the conventional view of liquid aluminum (l-Al) as a simple metal governed by the free-electron model, it exhibits unique bonding characteristics. This study uncovers a gradual transition from free electron to electride behavior in l-Al at high pressure and temperature, forming a type of two-component liquid where atomic and electride states coexist. The proportion of electride increases with pressure and temperature until reaching saturation, leading to notable changes in the pair-correlation function and coordination number of l-Al at saturation pressure.

Controllable topological phase transition ferroelectric-paraelectric switching in a ferromagnetic single-layer MMGeX family.

Recently, the emergence of two-dimensional (2D) multiferroic materials has opened a new perspective for exploring topological states. However, instances of tuning topological phase transitions through ferroelectric (FE) polarization in 2D ferromagnetic (FM) materials are relatively rare. Here, we found that 11 single layer (SL) materials, named the MMGeX family, possess both FE and FM properties.

Fiber Vector Light-Field-Based Tip-Enhanced Raman Spectroscopy.

Tip-enhanced Raman spectroscopy (TERS) has been extensively employed to investigate the light-matter interaction at the nanoscale. However, the current TERS strategies lack the ability to excite the low-background inhomogeneous electromagnetic field with significant enhancement of electric field, electric field gradient, and optomagnetic field, simultaneously. To overcome this, we developed a fiber vector light-field-based TERS strategy aimed at exploring the multipole Raman scattering processes of molecules.

Rapid Crystallization and Versatile Metalation of Acetylhydrazone-Linked Covalent Organic Frameworks for Heterogenous Catalysis.

Covalent organic frameworks (COFs) hold promise in heterogeneous metal catalysis benefiting from their robust, crystalline, and porous structures. However, synthetic challenges persist in prolonged crystallization times, limited metal loading, and uncertain coordination environments. Here, we present the rapid crystallization and versatile metalation of new acetylhydrazone-linked COFs (AH-COFs) by condensation of ketone and hydrazide components, featuring full conversion within 30 min under open-air and mild conditions.

Hybrid electromagnetic and moisture energy harvesting enabled by ionic diode films.

Wireless energy-responsive systems provide a foundational platform for powering and operating intelligent devices. However, current electronic systems relying on complex components limit their effective deployment in ambient environment and seamless integration of energy harvesting, storage, sensing, and communication. Here, we disclose a coupling effect of electromagnetic wave absorption and moist-enabled generation on carrier transportation and energy interaction regulated by ionic diode effect.

Elucidating Manganese Single-Atom Doping: Strategies for Fluorescence Enhancement in Water-Soluble Red-Emitting Carbon Dots and Applications for FL/MR Dual Mode Imaging.

The absence of the enhancement of fluorescence in carbon dots (CDs) through doping with transition metal atoms (TMAs) hinders the advancement of multi-modal bio-imaging CDs with high photoluminescence quantum yield (PLQY). Herein, Mn-atomically-doped R-CDs (R-Mn-CDs) with a high PLQY of 41.3% in water is presented, enabling efficient in vivo dual-mode fluorescence/magnetic resonance (MR) imaging.

Gate-Controlled Superconducting Switch in GaSe/NbSe van der Waals Heterostructure.

The demand for low-power devices is on the rise as semiconductor engineering approaches the quantum limit, and quantum computing continues to advance. Two-dimensional (2D) superconductors, thanks to their rich physical properties, hold significant promise for both fundamental physics and potential applications in superconducting integrated circuits and quantum computation. Here, we report a gate-controlled superconducting switch in GaSe/NbSe van der Waals (vdW) heterostructure.

Innovative Heating for the Nano Age: Exploring the Potentials of Carbothermal Shock.

Heating techniques have underpinned the progress of the material and manufacturing industries. However, the explosive development of nanomaterials and micro/nanodevices has raised more requirements for the heating technique, including but not limited to high efficiency, low cost, high controllability, good usability, scalability, universality, and eco-friendliness. Carbothermal shock (CTS), a heating technique derived from traditional electrical heating, meets these requirements and is advancing at a high rate.