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Harnessing the photoinduced phase transitions in organic crystals, especially the changes in shape and structure across various dimensions, offers a fascinating avenue for exact spatiotemporal control, which is crucial for developing future smart devices. In our study, we report a new photoactive molecular crystal made from (E)-2-(3-phenyl-allylidene)malonate ((E)-PADM). When exposed to ultraviolet (UV) light at 365 nm, this compound experiences an E-to-Z photoisomerization in liquid solution and a crystal-to-liquid phase transition in solid crystals. Remarkably, nanoscopic crystalline rods boost their melting rate and degree compared to bulk crystals, indicating that miniaturization enhances the photoinduced melting effect. Our results demonstrate a simple approach to rapidly drive molecular crystals into liquids via photochemical reactions and phase transitions. [ABSTRACT FROM AUTHOR]

The objective of this study was to screen non‐Saccharomyces yeast suitable for enhancing the aroma of Yinhong plum wine. Five non‐Saccharomyces yeasts with strong ester‐producing ability, namely, Wa3 (Wickerhamomyces anomalus), Hu12 (Hanseniaspora uvarum), Pk2A2, PkW2 and PkY2 (Pichia kluyveri), were selected from various naturally fermented fruit juices for molecular biological identification, analyses of physiological characteristics and tolerance and determination of their effects on the flavour of Yinhong plum wine. Analysis of brewing characteristics showed that they differed in their abilities of producing acetic acid, hydrogen sulfide, killer activity and tolerance. Among them, Wa3 showed the best tolerance to high concentrations of alcohol, sugar and SO2. Compared to the control Saccharomyces cerevisiae FX10, Yinhong plum wine fermented with non‐Saccharomyces yeast exhibited a decrease in alcohol content, while residual sugar, glycerol content and the types and quantities of volatile compounds all showed an increase. Among the fermented wines, PkY2 generated the highest content of ester compounds in the fermented wine, which was 5.66 times higher than that generated by the control. The compounds produced by PkY2 were closely related to various ethyl and acetate odour‐active compounds (odour‐active value >1), which could impart a rich floral and fruity aroma to Yinhong plum wine. Sensory analysis revealed that both floral and fruity aromas were significantly increased in Yinhong plum wine fermented by non‐Saccharomyces yeasts, with the highest scores of floral and fruity aromas for PkY2. In conclusion, a Pichia kluyveri strain, PkY2, with excellent brewing characteristics and potential for enhancing the aroma of Yinhong plum wine was identified. [ABSTRACT FROM AUTHOR]

Despite the low solubility of hydrogen isotopes (HIs) in tungsten (W), their concentration can reach up to ∼10 at.% after low-energy plasma irradiation. This is generally attributed to the vacancies that may accommodate excessive HIs. However, the kinetic energy of incident HIs transferred to W is far below the energy threshold to create a Frenkel pair, the underlying mechanism of defect production is still unclear. Here, we investigate the influence of H on the defect production in W using the molecular dynamic (MD) simulations. It is found that the threshold displacement energy (TDE) in bulk W slight decreases with the increasing of H concentration. This is due to the formation of H-vacancy complexes, which prevents the vacancy-interstitial recombination. More importantly, the H effects are significantly magnified in the surface region. On the one hand, the maximum kinetic energy transferred from 400 eV H to W can reach up to ∼21 eV due to the double-hit process, which is two times higher than that predicted by elastic collision model. On the other hand, the momentum transferred to W is completely random, including both the recoil direction upward and downward from the surface. Accordingly, the lowest TDE in W surface is only 15–21 eV at sub-surface layers with the depth of 6.7–11.1 Å, which is lower than the maximum kinetic energy transferred to W. Therefore, the low-energy HIs irradiation can create the defects in W surface directly. Our findings provide deep insight into defect production in W at sub-threshold energy and have wider implications for materials performance under low-energy ions irradiation. [ABSTRACT FROM AUTHOR]

Organic compounds that can respond to external stimuli and exhibit fluorescence changes have drawn increasing attention recently because of their potential applications in intelligent displays, optical data storage, anticounterfeiting, bioimaging, and sensors. Herein, we have synthesized two new organic compounds based on frameworks of anthracene and pyridine groups: 4‐(anthracen‐9‐yl) pyridine (AN9P) and 4‐(anthracen‐2‐yl) pyridine (AN2P). Both compounds, in solution and solid state, including polycrystals and single crystals, display reversible fluorescence transformations under alternate acid and base treatments. AN9P and AN2P solutions could be regulated to emit white‐light luminescence. The photoluminescence of the AN9P and AN2P polycrystals showed fast fluorescence changes with wide ranges (>300 nm) upon alternate acid and base stimuli and still exhibited remarkable fluorescence emission with almost no attenuation after 15 cycles of the reversible process. Both experimental and computational results suggested that the heteroatom nitrogen in the AN9P and AN2P molecules significantly influenced the intra‐ and intermolecular electronic interactions during the reversible protonation and deprotonation processes, resulting in changes in their frontier molecular orbitals and fluorescence emission characteristics. Our results provide a new facile approach to design molecular structures that realize highly dynamic photoluminescence changes in both liquid solution and solid crystal. [ABSTRACT FROM AUTHOR]

Electrical impedance tomography (EIT) is a radiation-free and noninvasive medical image reconstruction technique in which a current is injected and the reflected voltage is received through electrodes. EIT electrodes require good connection with the skin for data acquisition and image reconstruction. However, detached electrodes are a common occurrence and cause measurement errors in EIT clinical applications. To address these issues, in this study, we proposed a method for detecting faulty electrodes using the differential voltage value of the detached electrode in an EIT system. Additionally, we proposed the voltage-replace and voltage-shift methods to compensate for invalid data from the faulty electrodes. In this study, we present the simulation, experimental, and in vivo chest results of our proposed methods to verify and evaluate the feasibility of this approach. [ABSTRACT FROM AUTHOR]

Infrared detection technology has been widely applied in many areas. Unlike internal photoemission and the photoelectric mechanism, which are limited by the interface barrier height and material bandgap, the research of the hot carrier effect from nanometer thickness of metal could surpass the capability of silicon-based Schottky devices to detect mid-infrared and even far-infrared. In this work, we investigate the effects of physical characteristics of Cr nanometal surfaces and metal/silicon interfaces on hot carrier optical detection. Based on the results of scanning electron microscopy, atomic force microscopy, and X-ray diffraction analysis, the hot carrier effect and the variation of optical response intensity are found to depend highly on the physical properties of metal surfaces, such as surface coverage, metal thickness, and internal stress. Since the contact layer formed by Cr and Si is the main role of infrared light detection in the experiment, the higher the metal coverage, the higher the optical response. Additionally, a thicker metal surface makes the hot carriers take a longer time to convert into current signals after generation, leading to signal degradation due to the short lifetime of the hot carriers. Furthermore, the film with the best hot carrier effect induced in the Cr/Si structure is able to detect an infrared signal up to 4.2 μm. Additionally, it has a 229 times improvement in the signal-to-noise ratio (SNR) for a single band compared with ones with less favorable conditions. [ABSTRACT FROM AUTHOR]

The plasticity and hardness of metals are largely dependent on how dislocation interacts with solute atoms. Here, taking bcc molybdenum (Mo) as the example, the interaction of interstitial solutes carbon (C) and oxygen (O) with screw dislocation, and their influences on the dislocation motion, have been determined using first-principles calculations and thermodynamic models. Due to the incompact atomic structure and variation of electronic states in the dislocation core, C and O will segregate from the bulk system to the dislocation region. Notably, the presence of C/O at the dislocation induces the reconstruction of the core structure, from an easy-core to hard-core configuration. This originates from the fact that the hard-core structure provides a larger available volume at the interstitial site than the easy-core structure and, thus, facilitates the dissolution of C and O. More importantly, the addition of C/O in the dislocation significantly increases the Peierls stresses and double-kink formation enthalpies of screw dislocation in Mo, from 1.91 GPa and 1.18 eV for C/O-free dislocation to 5.63/4.69 GPa and 1.77/1.58 eV for C/O-saturated dislocation. Therefore, these interstitial solutes have a pinning effect on the dislocation motion, and this effect becomes stronger with higher segregating levels. This work reveals the profound effect of interstitial solutes on the properties of the dislocation core and provides a fundamental factor to account for the interstitial solutes-related phenomena in bcc metals. [ABSTRACT FROM AUTHOR]

Understanding the evolution of irradiation-induced defects is of critical importance for the performance estimation of nuclear materials under irradiation. Hereby, we systematically investigate the influence of He on the evolution of Frenkel pairs and collision cascades in tungsten (W) via using the object kinetic Monte Carlo (OKMC) method. Our findings suggest that the presence of He has significant effect on the evolution of irradiation-induced defects. On the one hand, the presence of He can facilitate the recombination of vacancies and self-interstitial atoms (SIAs) in W. This can be attributed to the formation of immobile He-SIA complexes, which increases the annihilation probability of vacancies and SIAs. On the other hand, due to the high stability and low mobility of He-vacancy complexes, the growth of large vacancy clusters in W is kinetically suppressed by He addition. Specially, in comparison with the injection of collision cascades and He in sequential way at 1223 K, the average sizes of surviving vacancy clusters in W via simultaneous way are smaller, which is in good agreement with previous experimental observations. These results advocate that the impurity with low concentration has significant effect on the evolution of irradiation-induced defects in materials, and contributes to our understanding of W performance under irradiation. [ABSTRACT FROM AUTHOR]

By performing the first-principles calculations, we explore the dissolution and diffusion of hydrogen (H) in hexagonal closed packed zirconium (Zr) as well as its interaction with vacancy. We show that the tetrahedral (TE) interstitial site is the favorable trapping site for a single H atom with the solution energy of −0.45 eV. Such a negative solution energy is due to the strong electronic bond between H and neighboring Zr atoms. Moreover, the energy barrier for the migration of H from a TE site to its 1NN and 2NN TE site is 0.12 eV and 0.42 eV, respectively. It is noteworthy that the first path only slightly contributes to the experimentally measured H diffusivity in Zr, because the H atom is trapped by two nearest neighboring TE sites. Thus, the effective activation energy for H diffusion in Zr should be mainly determined by the second path, and the corresponding energy barrier is 0.42 eV. Furthermore, since the electronic density (available volume) in vacancy is lower (larger) than that of interstitial site, vacancy is a strong trap for H atoms in Zr. We demonstrate that the maximum of 8 H atoms can be accommodated in a mono-vacancy without the observation of H 2 molecule. These results can provide a basis to develop Zr materials in nuclear cladding devices. [ABSTRACT FROM AUTHOR]

We have investigated the dissolution, diffusion, and retention of hydrogen (H) in tungsten-rhenium (W-Re) sigma (σ) phase using a first-principles method and thermodynamic models, in order to explore the influence of Re-rich precipitation on H behaviors in W. Taking the most stable W-Re σ phase (W-33.3 at.% Re) as an example, it is found that the solution energy of H at most interstitial sites (>80%) in W-Re σ phase is much lower than that in pure W. Specifically, the H solution energy at most stable interstitial site in W-Re σ phase is only 0.47 eV, ~54% lower than that in pure W. This can be attributed to that W-Re σ phase provides the larger available volume for interstitial H than the pure W, weakening the W-H repulsive interaction. Moreover, it has been demonstrated that this trend is almost independent on the Re concentration in W-Re σ phase. We have further determined the interaction between H atoms and mono-vacancy in W-Re σ phase based on the calculation of H trapping energies and the Polanyi-Wigner equation. The W-type and Re-type vacancy can accommodate 10 and 5 H atoms at room temperature (RT) in σ phase, respectively, and thus the average trapping capability of vacancy for H in σ phase is stronger than that in pure W (~6 H atoms at RT). Consequently, our calculations reveal that the Re-rich precipitation (both interstitial and vacancy sites) can serve as the strong trapping centers for H in W, significantly enhancing the H retention, which is entirely different from the negative effect of dispersed-Re/small Re clusters. • We investigate the dissolution, diffusion and retention of H in W-Re σ phase. • The H solution energy at interstitial sites in σ phase is lower than that in bcc W. • The trapping capability of vacancy for H in σ phase is stronger than that in bcc W. • Re-rich precipitation will significantly enhance the H retention in W-PFM. [ABSTRACT FROM AUTHOR]

The self‐assembly of triazole amphiphiles was examined in solution, the solid state, and in bilayer membranes. Single‐crystal X‐ray diffraction experiments show that stacked protonated triazole quartets (T4) are stabilized by multiple strong interactions with two anions. Hydrogen bonding/ion pairing of the anions are combined with anion–π recognition to produce columnar architectures. In bilayer membranes, low transport activity is observed when the T4 channels are operated as H+/X− translocators, but higher transport activity is observed for X− in the presence of the K+‐carrier valinomycin. These self‐assembled superstructures, presenting intriguing structural behaviors such as directionality, and strong anion encapsulation by hydrogen bonding supported by vicinal anion–π interactions can serve as artificial supramolecular channels for transporting anions across lipid bilayer membranes. [ABSTRACT FROM AUTHOR]

The cyclic depsipeptide cereulide toxin it is a very well‐known potassium electrogenic ionophore particularly sensitive to pancreatic beta cells. The mechanistic details of its specific activity are unknown. Here, we describe a series of synthetic substituted cereulide potassium ionophores that cause impressive selective activation of glucose‐induced insulin secretion in a constitutive manner in rat insulinoma INS1E cells. Our study demonstrates that the different electroneutral K+ transport mechanism exhibited by the anionic mutant depsipeptides when compared with classical electrogenic cereulides can have an important impact of pharmacological value on glucose‐stimulated insulin secretion. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) in tumors consumes 1O2 and seriously inhibits the PDT effect. MnO2-coated porphyrin metal–organic frameworks are developed to realize the oxidation of GSH by MnO2 for enhanced PDT, activated MR imaging, and controllable release of DOX as magnetic resonance imaging guided drug–PDT dual-therapy. [ABSTRACT FROM AUTHOR]

Abstract We investigate the effects of the hydrostatic strain on the dissolution, diffusion, and clustering of alloying/transmutation elements rhenium (Re) and osmium (Os) in tungsten (W) by using the first-principles method in combination with thermodynamic models. Results show that the strain has significant influences on the dissolution/diffusion of Re/Os as well as their interactions with defects, and thus enhances the clustering of Re/Os in W. For defect-free case, the tensile strain can enhance the clustering of Re/Os in W, while the compressive one can inhibit the formation of Re/Os clusters. Specifically, the energy barrier of Os nucleation in W under 5% tensile (compressive) strain is 0.52 eV (2.32 eV), which is 66% lower (53% higher) than that in strain-free W, suggesting that the tensile/compressive strain has a prominent effect on the clustering of Os in W. Further, the tensile strain can improve the stability of multi Re/Os complexes with SIA and reduce the vacancy-mediated diffusion energy barrier of Re/Os, indicating that the tensile strain can also facilitate the clustering of Re/Os in W with defects. Based on our calculated results, we thus propose a strain-triggered cascading effect of Re/Os clustering in W, i.e., the dissolution and accumulation of Re/Os induce a tensile strain in W lattice surrounding the Re/Os atoms, which in turn further facilitates the clustering of Re/Os in W. [ABSTRACT FROM AUTHOR]

Abstract: Self‐assembled alkyl‐ureido‐benzo‐15‐crown‐5‐ethers are selective ionophores for K+ cations, which are preferred to Na+ cations. The transport mechanism is determined by the optimal coordination rather than classical dimensional compatibility between the crown ether hole and the cation diameter. Herein, we demonstrate that systematic changes of the structure lead to unexpected modifications in the cation‐transport activity and suffice to produce adaptive selection. We show that the main contribution to performance arises from optimal constraints on the conformational freedom, which are determined by the binding macrocycles, the nature of the hydrogen‐bonding groups, and the hydrophobic tails. Simple changes to the flexible 15‐crown‐5‐ether lead to selective carriers for Na+. Hydrophobic stabilization of the channels through mutual interactions between lipids and variable hydrophobic tails appears to be an important cause of increased activity. Oppositely, restricted translocation is achieved when constrained hydrogen‐bonded macrocyclic relays are less dynamic in a pore superstructure. [ABSTRACT FROM AUTHOR]

Using a first-principles method in combination with thermodynamic models, we investigate the interaction between rhenium/osmium (Re/Os) and defects to explore the mechanism of radiation-induced Re/Os precipitation in tungsten (W). We demonstrate that radiation-induced defects play a key role in the solute precipitation in W, especially for self-interstitial atoms (SIAs). The presence of SIAs can significantly reduce the total nucleation free energy change of Re/Os, and thus facilitate the nucleation of Re/Os in W. Further, SIA is shown to be easily trapped by Re/Os once overcoming a low energy barrier, forming a W-Re/Os mixed dumbbell. Such W-Re/Os dumbbell forms a high stable Re/Os-Re/Os dumbbell structure with the substitutional Re/Os atoms, which can serve as a trapping centre for subsequent interstitial-Re/Os, leading to the growth of Re/Os-rich clusters. Consequently, an interstitial-mediated migration and aggregation mechanism for Re/Os precipitation in W has been proposed. Our results reveale that the alloying elements-defects interaction has significantly effect on their behaviors under irradiation, which should be considered in the design of W-based alloys for future fusion devices. [ABSTRACT FROM AUTHOR]