•An adaptive, separable reversible data hiding scheme in encrypted image is proposed.•Analogues stream-cipher and block permutation are used to encrypt original image.•Classification and selection ...for encrypted blocks are conducted during embedding.•An accurate prediction strategy was employed to achieve perfect image recovery.•Our scheme has better rate-distortion performance than some state-of-the-art schemes.
In this paper, an adaptive reversible data hiding scheme for encrypted images is proposed. Content owner uses an analogues stream-cipher and block permutation to encrypt non-overlapping blocks of original image through encryption key. Then, data hider classifies encrypted blocks into two sets corresponding to smooth and complex regions in original image. With data-hiding key, spare space is vacated to accommodate additional bits by compressing LSBs of the block set corresponding to smooth region. Separable operations of data extraction, direct decryption and image recovery are conducted by receiver according to the availability of encryption key and data-hiding key. Through an accurate prediction strategy, perfect image recovery is achieved. Since only a portion of blocks are modified during embedding, the directly-decrypted image quality is satisfactory. Also, more bits can be embedded into the blocks belonging to smooth set, hence, embedding rate is acceptable. Experimental results demonstrate the effectiveness of our scheme.
•A thin metallic interfacial layer enables highly reversible Zn electrodeposition.•High average Coulombic efficiency of 99.7% for 3000 cycles is achieved at 1 mAh cm−2.•Dendrite-free Zn ...electrodeposition for 2500 cycles is attained at 1 mA cm−2.
Zinc (Zn) metal is regarded as a promising anode material for aqueous batteries owing to its high natural abundance, high theoretical capacity and low redox potential. However, aqueous Zn metal anodes suffer from poor reversibility, as shown by their low Coulombic efficiency (CE) and dendrite growth during long-term plating/stripping. In this study, we report that a thin metallic Cu or Ag interfacial layer, made by a facile thermal evaporation method, can enable highly reversible and nondendritic plating/stripping of Zn metal anodes in aqueous batteries. This is attributed to the synergy of fast Zn-ion migration through the tiny gaps in the interfacial layer as well as its high interfacial affinity for Zn metal. High average CE of 99.7% are achieved over 3000 plating/stripping cycles at 10 mA cm−2 and 1 mAh cm−2. The modified Zn anode can stably cycle for more than 2500 cycles (5000 h) of plating/stripping at 1 mA cm−2 and a 500 cycle-life is realized for a full cell paired with a MnO2 cathode. This finding opens up a promising avenue to develop the next-generation Zn metal-based energy storage technologies.
Fibrosis and apoptosis are juxtaposed in pulmonary disorders such as asthma and the interstitial diseases, and transforming growth factor (TGF)-β1 has been implicated in the pathogenesis of these ...responses. However, the in vivo effector functions of TGF-β1 in the lung and its roles in the pathogenesis of these responses are not completely understood. In addition, the relationships between apoptosis and other TGF-β1–induced responses have not been defined. To address these issues, we targeted bioactive TGF-β1 to the murine lung using a novel externally regulatable, triple transgenic system. TGF-β1 produced a transient wave of epithelial apoptosis that was followed by mononuclear-rich inflammation, tissue fibrosis, myofibroblast and myocyte hyperplasia, and septal rupture with honeycombing. Studies of these mice highlighted the reversibility of this fibrotic response. They also demonstrated that a null mutation of early growth response gene (Egr)-1 or caspase inhibition blocked TGF-β1–induced apoptosis. Interestingly, both interventions markedly ameliorated TGF-β1–induced fibrosis and alveolar remodeling. These studies illustrate the complex effects of TGF-β1 in vivo and define the critical role of Egr-1 in the TGF-β1 phenotype. They also demonstrate that Egr-1–mediated apoptosis is a prerequisite for TGF-β1–induced fibrosis and remodeling.
The practical applications of magnetocaloric materials for magnetic refrigeration require not only large magnitude but also reversibility, as well as room-temperature operating temperature, of the ...magnetocaloric effect. However, it is a complex problem to simultaneously meet these demands in the Heusler-type Ni-(Co)-Mn-X (X = In, Sn, Sb, Ga) magnetic shape memory alloys which are a promising candidate for magnetocaloric materials, owing to the interdependence of magnetostructural transformation parameters. Here, through synergic tuning of magnetostructural transformation parameters via alloying with Ti in Ni42-xTixCo9Mn39Sn10 alloys, we achieved a large reversible room-temperature magnetocaloric effect. By alloying with a proper amount of Ti, the martensitic transformation temperature was brought down to room temperature and the sensitivity of transformation temperature to magnetic field change was greatly enhanced with the transformation entropy change still remaining a large value, while the thermal hysteresis and the transformation interval only slightly increased. Thus, the field required to induce the complete and reversible transformation was significantly reduced. As a result, a large reversible room-temperature magnetic entropy change ΔSm of 18.7 J kg−1 K−1 under 5 T was achieved in the Ni41Ti1Co9Mn39Sn10 alloy. This is the first report on reversible ΔSm in Ni-Mn-Sn-based Heusler alloys and the ΔSm we achieved represents the highest reversible ΔSm under 5 T reported heretofore in Ni-Mn-based Heusler alloys. Furthermore, the Ni41Ti1Co9Mn39Sn10 alloy shows good compressive properties and stable martensitic transformation during thermal cycling, beneficial for potential magnetocaloric applications. This study is instructive for the development of high-performance magnetocaloric materials for room-temperature magnetic refrigeration.
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Magnesium hydrides (MgH2) have attracted extensive attention as solid-state H2 storage, owing to their low cost, abundance, excellent reversibility, and high H2 storage capacity. This review ...comprehensively explores the synthesis and performance of Mg-based alloys. Several factors affecting their hydrogen storage performance were also reviewed. The metals addition led to destabilization of Mg–H bonds to boost the dehydrogenation process. A unique morphology could provide more available active sites for the dissociation/recombination of H2 and allow the activation energy reduction. Also, an appropriate support prevent the agglomeration of Mg particles, hence, sustains their nanosize particles. Moreover, the perspective of avenues for future research presented in this review is expected to act as a guide for the development of novel Mg-based H2 storage systems. New morphological shape of catalysts, more unexplored and highly potential waste materials, and numerous synthesis procedures should be explored to further enhance the H2 storage of Mg-based alloys.
•Alloying of Mg is an efficient strategy to enhance hydrogen storage performance.•Numerous synthesis route could be explored to produce effective Mg-based alloy.•Diverse metal loadings could differently affect the hydrogen storage performance.•Proper morphology can hasten dissociation and recombination of hydrogen.•Appropriate supports sustain the nanosize and disperse the vital species in alloys.
Rechargeable aqueous zinc ion batteries (AZIBs) promise high energy density, low redox potential, low cost and safety; however, their cycle performances are seriously insufficient to restrict the ...progress in this field. We propose a new concept of atomic electrode formed on the graphdiyne (GDY). This new idea electrode was synthesized by selectively, uniformly, and stably anchoring Zn atoms on GDY at the beginning of plating. The Zn atoms are induced to grow into larger size Zn clusters, which continue to grow into nanoflat. Finally, a new heterojunction interface is formed on GDY without any Zn dendrites and side reactions, even at high current densities. Such stepwise induction of growth greatly suppresses the formation of Zn dendrites, resulting in high electroplating/stripping reversibility and lifespan of AZIBs.
Gradually inducing an increase in size from atoms to nanoflat surfaces shows the great power of the conjugated, multi‐pore structure of graphdiyne (GDY). An electrode for aqueous zinc‐ion batteries obtained by anchoring Zn atoms on graphdiyne shows excellent electroplating/stripping reversibility and lifespan without any Zn dendrites and side reactions, even at high current densities.
Co‐Free Layered Cathodes
In article number 2204241, Hailong Wang, Xiangming He, and co‐workers report a cation vacancy assisted Al substitution strategy to enhance the reversibility of Co‐free ...layered cathodes. A small amount of cation vacancies greatly enhances Li+ diffusivity and effectively mitigates lattice strain of the Co‐free layered cathode, which gives rise to a large reversible capacity and enhanced coulombic efficiency during electrochemical cycling.
Humidity‐ and moisture‐induced degradation has been a longstanding problem in perovskite materials, affecting their long‐term stability during applications. Counterintuitively, the moisture is ...leveraged to tailor the reversible hydrochromic behaviors of a new series of 2D Dion–Jacobson (DJ) perovskites for reconfigurable optoelectronics. In particular, the hydrogen bonds between organic cations and water molecules can be dynamically modulated via moisture removal/exposure. Remarkably, such modulation confines the movement of the organic cations close to the original position, preventing their escape from crystal lattices. Furthermore, this mechanism is elucidated by theoretical analysis using first‐principles calculations and confirmed with the experimental characterizations. The reversible fluorescent transition 2D DJ perovskites show excellent cyclical properties, presenting untapped opportunities for reconfigurable optoelectronic applications. As a proof‐of‐concept demonstration, an anti‐counterfeiting display is shown based on patterned reversible 2D DJ perovskites. The results represent a new avenue of reconfigurable optoelectronic application with 2D DJ perovskites for humidity detection, anti‐counterfeiting, sensing, and other emerging photoelectric intelligent technologies.
A comprehensive mechanistic study of reconfigurable optoelectronic properties based on a nontrivial library of 2D Dion–Jacobson perovskites with diamino group ligands by exposing/removing moisture is presented. The key to the moisture‐controlled reconfigurable properties lies in the formation of hydrogen bonding between the diamino group and water molecules, preventing their escape.
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