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Many-Body eXpansion (MBX) is a C++ library that implements many-body potential energy functions (PEFs) within the many-body energy (MB-nrg) formalism. MB-nrg PEFs integrate an underlying polarizable model with explicit machine-learned representations of many-body interactions to achieve chemical accuracy from the gas to the condensed phases. MBX can be employed either as a stand-alone package or as an energy/force engine that can be integrated with generic software for molecular dynamics and Monte Carlo simulations. MBX is parallelized internally using Open Multi-Processing and can utilize Message Passing Interface when available in interfaced molecular simulation software. MBX enables classical and quantum molecular simulations with MB-nrg PEFs, as well as hybrid simulations that combine conventional force fields and MB-nrg PEFs, for diverse systems ranging from small gas-phase clusters to aqueous solutions and molecular fluids to biomolecular systems and metal-organic frameworks.

Photoluminescent (PL) anti‐counterfeiting plays a critical role in encrypted information and anti‐counterfeiting. Dynamic PL anti‐counterfeiting technology provides advanced security features compared with static counterparts. Yet, many current dynamic luminescent materials rely solely on an optical storage mechanism, leading to a lack of diversification and making them vulnerable to replication. Here, dynamic PL emission triggered by ambient temperature variations is addressed. By modifying the sintering atmospheres and non‐stoichiometric ratio of MgGa2O4 (MGO) samples, the concentration of intrinsic defects of the host are modified, resulting in temperature‐sensitive PL output dynamically manipulated from blue to green to red. Density‐functional theory (DFT) analysis elucidates the formation energies of intrinsic defects in the MGO samples, revealing that the self‐activated blue, green, and red emissions stem from lattice defects, [GaO6], antisite defects GaMg•${\mathrm{Ga}}_{{\mathrm{Mg}}}^{\mathrm{ \bullet }}$, and interstitial oxygen (Oi${{\mathrm{O}}}_{\mathrm{i}}$), respectively. Additionally, by monitoring the luminescence lifetime, and the thermoluminescence (TL) curves of the MGO samples, it is shown that the dynamic PL emission is generated by a combination of thermally assisted carrier migration and thermal compensation from trapping centers. Herein, a dual‐channel encrypted dot matrix is designed to enhance information transfer security through the interference between the dual channels, showcasing the practical application of this dynamic anti‐counterfeiting technique. [ABSTRACT FROM AUTHOR]

Manipulation of photoluminescence (PL) and persistent luminescence (PersL) provides a powerful tool for anti‐counterfeiting applications. Here, Sb3+‐doped CsCdCl3 perovskite single crystals (SCs) can be selectively irradiated via utilizing ultra‐fast femtosecond (fs) laser, creating tunable PL colors and PersL duration with high precision. The PL color of the synthesized SCs changes from cyan to orange along with the wavelength of the fs laser, for the successful regulation of the optical procedure from a single‐photon to a two‐photon absorption process. Moreover, an orange PersL of CsCdCl3:Sb3+ SC is observed after being charged with a fs laser, and the corresponding duration time can be feasibly controlled with the pump wavelength. In particular, CsCdCl3:Sb3+ is capable of ultrafast carrier capture (1 s) under fs laser compared to ultraviolet lamp pre‐irradiation enabling a high‐resolution micro‐PersL in photon trapping/de‐trapping modes. These findings not only give a new solution for the fabrication high‐resolution micro‐PL and trajectory‐writing micro‐PersL patterns, but also provide a deep insight to understand the photon–matter interactions. [ABSTRACT FROM AUTHOR]

Scintillators with high spatial‐resolution and high‐stability are highly desirable for X‐ray imaging applications at unpredictable environments. To challenge state‐of‐the‐art technology, it is necessary to design high thermal stable scintillators with high‐resolution and high light yield. In this work, the zero‐thermal‐quenching Lu3Al5O12:Ce3+ (LuAG: Ce3+) transparent ceramics (TCs) is synthesized with high optical transparency. The thermoluminescence (TL) curves of the as‐obtained TCs demonstrate that the formation of the oxygen vacancies, acting as the trapping centers, can capture the carriers and then contribute to the enhancement of its thermals stability via the thermal compensation effect. The exceptional thermal‐stability of the TCs scintillator endows the monitoring of the dynamic changes of the internal structure of the objective samples without any ghosting effects during heating. In addition, given the ultra‐high uniform, transparency, and fast light decay of the TCs scintillator, the excellent spatial resolution (≈112 lp mm−1) of the X‐ray microscopic imaging is realized. These results undeniably demonstrate that the as‐obtained LuAG: Ce3+ TCs have great prospects for advancement in X‐ray detectors. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML) materials can convert mechanical stimuli into visible signals for real-time visualization of stress sensing. Since stress sensing solely based on ML absolute strength is susceptible to the external environment, ratiometric ML detection approach is expected to provide stress description with improved accuracy and stability. In this study, a stress-dependent ratiometric ML is achieved using the Eu2+ and Mn2+ co-doped SrMg2(PO4)2 (SMP) phosphors, enabling color-resolved visualization of uploaded stress stimulus. Moreover, the linear relationship between the ML intensity ratio (MLIR) and the applied stress leads to an obvious variation in ML color upon different applied stress. Herein, the as-explored ML composites films as an artificial skin could provide a visualization and quantification tool for monitoring human knee motion with great accuracy and precision. [ABSTRACT FROM AUTHOR]

With the widespread implementation of COVID-19 prevention and control measures during the pandemic, online classes have become a normal and indispensable part of college students' lives. Analysis of the factors affecting college students' behavioural intention towards online classes will help improve online class quality. This paper sets up a model to analyse the factors that may affect such intentions. The results show that social influence, performance expectancy, effort expectancy, perceived usefulness and perceived ease of use have a significant positive effect on college students' behavioural intention, and enabling environment(i.e. the infeasibility of offline teaching due to the pandemic)has a significant negative effect on it. Gender and voluntariness, as moderator variables, also clearly influence behavioural intention. Based on pandemic prevention and control measures, along with education reform and modernisation, this paper offers valuable suggestions to online learning platform and education administrators. [ABSTRACT FROM AUTHOR]

The development of highly stable and ultra‐long organic room temperature phosphorescence (RTP) materials holds great promise for applications in anti‐counterfeiting and information protection. To improve the encryption level, the exploration of organic materials with tunable phosphorescence and afterglow features is in urgent need. Hereby, a series of long‐lived organic systems with RTP is developed by incorporating benzocarbazole derivatives into a polyvinyl alcohol (PVA) matrix (BCz@PVA). Notably, the BCz@PVA film exhibits outstanding RTP behavior with an ultralong phosphorescence lifetime (τp) of 2.09 s, high phosphorescence quantum yield (Φp) of 46.335%, and an ultra‐long afterglow duration of 15 s. Moreover, the BCz@PVA film maintains excellent RTP performance even after being placed in ambient conditions for 60 days. Theoretical calculations reveal that the excellent RTP performance of BCz@PVA film is attributed to the stronger intermolecular interactions, the smaller energy gap (ΔEst) between the singlet and triplet states, and stable molecular stacking mode. Furthermore, color‐tunable photoluminescence (PL), distinct τp, and afterglow duration are successfully achieved by adjusting the position of the Br substituent on the benzene ring. Based on their diverse RTP performances and excellent stability, the corresponding BCz@PVA film provides successful application for multi‐level high‐security anti‐counterfeiting and information protection. [ABSTRACT FROM AUTHOR]

Monitoring the real‐time quality and validity of thermo‐sensitive foods during storage and transportation can be achieved with time‐temperature indicators (TTIs). However, the available TTIs still need to be improved in terms of accuracy, recoverability, environmental tolerance, and quantitative monitoring. Here, a novel TTI based on the optical signals originating from the as‐explored Sr3Y2Ge3O12: Mn2+, Er3+ (SYGO: Mn2+, Er3+) phosphor is developed. Thanks to the fact that the release of the captured carriers is tightly related to the storage time and ambient temperature, distinct optical signals of the as‐obtained TTI under multi‐stimulus (980 nm laser irradiation, thermal stimulation, and mechanical force) can be distinguished to judge the validity of temperature‐sensitive products. This work reveals the promising potential of SYGO: Mn2+, Er3+ phosphors with cryogenic optical storage properties as advanced TTIs, especially for packaged products in cold chain logistics. [ABSTRACT FROM AUTHOR]