Manipulating Oxygen Vacancies in γ-GaO Nanocrystals: Correlation between Defect Location, Charge State, and Photophysical Properties.

Recent advancements in colloidal synthesis have enabled precise control of extrinsic dopants in semiconductor nanocrystals (NCs), enriching our understanding of dopant-exciton interactions and opening new avenues for controlling NC properties. However, the manipulation of intrinsic defects in colloidal NCs remains challenging. Here, we demonstrate regulation of oxygen vacancy concentration and location in γ-GaO NCs, significantly altering their photoluminescent properties.

The Evaluation of Interface Quality in HfO Films Probed by Time-Dependent Second-Harmonic Generation.

Time-dependent second-harmonic generation (TD-SHG) is an emerging sensitive and fast method to qualitatively evaluate the interface quality of the oxide/Si heterostructures, which is closely related to the interfacial electric field. Here, the TD-SHG is used to explore the interface quality of atomic layer deposited HfO films on Si substrates. The critical SHG parameters, such as the initial SHG signal and characteristic time constant, are compared with the fixed charge density (Qox) and the interface state density (Dit) extracted from the conventional electrical characterization method.

Synthesis and Characterization of Multiple Stimuli-Responsive Fluorescent Polymer Hydrogels Based on Terpyridine and -Isopropylacrylamide.

A series of stimuli-responsive fluorescent hydrogels were successfully synthesized via micelle radical copolymerization of hydrophilic acrylamide (AM), hydrophobic chromophore terpyridine-based monomer (TPY), and -isopropylacrylamide (NIPAM). These hydrogels presented blue emissions (423-440 nm) under room temperature, which is caused by the π-π* transition of the conjugated structures. Once the ambient temperature was increased to 55 °C, the fluorescence color changed from blue (430 nm) to pink (575 nm) within 10 min, subsequently to yellow (535 nm), and eventually back to pink.

Robust room temperature perpendicular magnetic anisotropy and anomalous Hall effect of sputtered NiCoOfilm.

Inverse spinel ferrimagnetic NiCoO(NCO) exhibits volatile physical properties due to the complex ion/valence occupation, which complicates the study its intrinsic properties. In this work, robust room temperature perpendicular magnetic anisotropy (PMA) is distinctly observed in high-quality RF-sputtered NCO film down to 3 uc (2.4 nm), confirmed by the room temperature anomalous Hall effect.

Tourism image classification based on convolutional neural network SqueezeNet--Taking Slender West Lake as an example.

Tourism image classification plays an important role in the study of clarifying the real perception of tourism resources by tourists, which cannot be studied in depth by human vision alone. The development of convolutional neural networks in computer vision brings new opportunities for tourism image classification research. In this study, SqueezeNet, a lightweight convolutional neural network, was selected and improved on the basis of the original model for 3740 Slender West Lake tourism image datasets.

A Supramolecular Hydrogel Based on Copolymers of Acrylic Acid and Maleic Anhydride Derivatives with Terpyridine Motifs.

A kind of terpyridine derivative () in which the amino was incorporated by a short alkyl chain was synthesized. Through grafting of terpyridine units into the hydrophilic copolymers of maleic anhydride and acrylic acid via the reaction of the amino groups in and the maleic anhydride units, a series of gelator polymers-, , and -containing different contents of terpyridine units was synthesized. Under coordination of Ni and terpyridine ligands in linear polymers, the supramolecular hydrogels , , and with different cross-linking degrees were prepared.

The Positive Temperature Coefficient of Resistivity in BiFeO Films.

The use of lead-free ceramic film materials with positive temperature coefficient of resistivity (PTCR) is widespread in temperature heaters and sensors in micro-electromechanical systems. In this research, the out of plane transport properties of the BiFeO (BFO) films have been studied. Surprisingly, PTCR was found in the BFO ceramic films due to the strongly correlated interaction between the multiferroic material BFO and the superconductor YBCO perovskite oxides.

Tunable 2D Group-III Metal Alloys.

Chemically stable quantum-confined 2D metals are of interest in next-generation nanoscale quantum devices. Bottom-up design and synthesis of such metals could enable the creation of materials with tailored, on-demand, electronic and optical properties for applications that utilize tunable plasmonic coupling, optical nonlinearity, epsilon-near-zero behavior, or wavelength-specific light trapping. In this work, it is demonstrated that the electronic, superconducting, and optical properties of air-stable 2D metals can be controllably tuned by the formation of alloys.

Synthesis and Characterization of Metallo-Supramolecular Polymers Based on Benzodipyrrolidone.

A simple route to the preparation of benzodipyrrolidone (BDP) based monomeric building blocks containing 2,2':6',2″-terpyridines is reported from a common precursor 4'-(4-pinacolatoboronphenyl)-2,2':6',2″-terpyridine via Suzuki coupling reaction. Self-assembly polymerization with ruthenium (II) ions under mild conditions yielded a series of novel metallo-supramolecular polymers with weak donor-acceptor (D-A) structures based on benzodipyrrolidone. The structure of the bridge connected BDP with terpyridine have a significant impact on the wavelength and intensity of the intramolecular charge transfer (ICT) absorption peak.

Terpyridine-Containing π-Conjugated Polymers for Light-Emitting and Photovoltaic Materials.

2,2':6',2″-Terpyridine (tpy) is a versatile moiety used in the construction of small novel molecules or polymers. Extending or coupling tpy with π-conjugation structures can result in interesting optoelectronic properties. This mini-review summarizes the significant progress made over the past decades in the study of tpy-containing π-conjugated polymers and their application in light-emitting and photovoltaic materials.

Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean.

Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth-ocean-atmosphere dynamic exchange of elements. The ratios' dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally.

Comparative Study on the Elucidation of Sedimentary Phosphorus Species Using Two Methods, the SMT and SEDEX Methods.

Sedimentary phosphorus (P) forms are important representatives of P sources and their bioavailability as well as the potential of sediments to release P in water. In this study, surface sediments along a transect of the Changjiang Estuary and two transects along the Andong salt marsh in the southwest of Hangzhou Bay were subjected to the elucidation of sedimentary P species using the standards, measurements, and testing (SMT) and sequential extraction (SEDEX) methods. The results showed that the mean sedimentary P forms elucidated by the SMT method were as follows: organic P (OP; ∼11-14 mg/kg; ∼30-45% of total P; TP) > apatite P (∼5-15 mg/kg; ∼21-36% TP) > Fe/Al-P (∼8-14 mg/kg; ∼31-34% TP), with inorganic P (IP) composing 54-70% of TP.

Earthquake and typhoon trigger unprecedented transient shifts in shallow hydrothermal vents biogeochemistry.

Shallow hydrothermal vents are of pivotal relevance for ocean biogeochemical cycles, including seawater dissolved heavy metals and trace elements as well as the carbonate system balance. The Kueishan Tao (KST) stratovolcano off Taiwan is associated with numerous hydrothermal vents emitting warm sulfur-rich fluids at so-called White Vents (WV) and Yellow Vent (YV) that impact the surrounding seawater masses and habitats. The morphological and biogeochemical consequences caused by a M5.

Metallo-Supramolecular Hydrogels from the Copolymers of Acrylic Acid and 4-(2,2':6',2″-terpyridin-4'-yl)styrene.

Hydrophilic copolymers containing 2,2':6',2″-terpyridine moieties and acrylic acid (AA) units poly (acrylic acid-co-4-(2,2':6',2″-terpyridin-4'-yl)styrene) (P(AA-co-TPY)) were synthesized and characterized. Coordinated with different transition metal ions, the dilute aqueous solution of the copolymers exhibited red-shifted UV-vis absorption peaks of π-π* transition from 317 to 340 nm. Further, interacting with iron ions, the copolymer showed new absorption peaks at a longer wavelength region (570 nm) and the absorption intensity enhanced with increase of the ion concentration.

Characteristics of Authigenic Minerals around the Sulfate-Methane Transition Zone in the Methane-Rich Sediments of the Northern South China Sea: Inorganic Geochemical Evidence.

Sediments at marine cold seep areas provide potential archives of past fluid flow, which allow insights into the evolution of past methane seepage activities. However, signals for anaerobic oxidation of methane (AOM) might be obscured in bulk sediments in cold-seep settings due to several factors, especially flood and turbidite deposition. Comprehensive inorganic data were gathered in this study to explore the availability of related records at cold seeps and to provide insights into the evolution of past methane seepage activities.

A polymeric ionic liquid as a cathode interlayer of organic photovoltaics with improved reproducibility.

A polymeric ionic liquid (PIL) was synthesized from a small-molecule one (MIL, the monomer), and they were used as cathode interlayers in organic solar cells. Compared with the MIL, the PIL can form a more uniform film for full coverage of an active layer and efficient cathode modification, resulting in higher device efficiency and reproducibility.

An All-Solid-State Silicate Ion-Selective Electrode Using PbSiO₃ as a Sensitive Membrane.

Ion-Selective Electrode (ISE) is an emerging technology for in situ monitoring of the chemical concentrations of an aqueous environment. In this work, we reported a novel all-solid-state silicate ISE, using an Ag/Pb/PbSiO₃ electrode. This electrode responded to aqueous SiO₃ with a reasonable slope of -31.

Magnetotransport Anomaly in Room-Temperature Ferrimagnetic NiCo O Thin Films.

The inverse spinel ferrimagnetic NiCo O presents a unique model system for studying the competing effects of crystalline fields, magnetic exchange, and various types of chemical and lattice disorder on the electronic and magnetic states. Here, magnetotransport anomalies in high-quality epitaxial NiCo O thin films resulting from the complex energy landscape are reported. A strong out-of-plane magnetic anisotropy, linear magnetoresistance, and robust anomalous Hall effect above 300 K are observed in 5-30 unit cell NiCo O films.

Submarine Groundwater Discharge helps making nearshore waters heterotrophic.

Submarine groundwater discharge (SGD) is the submarine seepage of all fluids from coastal sediments into the overlying coastal seas. It has been well documented that the SGD may contribute a great deal of allochthonous nutrients to the coastlines. It is, however, less known how much carbon enters the ocean via the SGD.

Enhanced Piezoelectric Response in Hybrid Lead Halide Perovskite Thin Films via Interfacing with Ferroelectric PbZrTiO.

We report a more than 10-fold enhancement of the piezoelectric coefficient d of polycrystalline CHNHPbI (MAPbI) films when interfacing them with ferroelectric PbZrTiO (PZT). Piezoresponse force microscopy (PFM) studies reveal [Formula: see text] values of 0.3-0.

Preparation of hollow iron/halloysite nanocomposites with enhanced electromagnetic performances.

Nanostructures loaded on halloysite nanotubes (HNTs) have attracted global interest, because the nanotubular HNTs could extend the range of their potential applications. In this study, we fabricated a novel nanocomposite with hollow iron nanoparticles loaded on the surface of HNTs. The structure of the iron nanoparticles can be adjusted by ageing time.

Indications of magnetic coupling effects in spin cross-over molecular thin films.

Room temperature isothermal reversible spin crossover switching of [Fe(HB(pz))(bipy)] thin films is demonstrated. The magnetic oxide substrate locks the [Fe{HB(pz)}(bipy)] largely in a low spin state. With an X-ray fluence, excitation to a high spin state occurs, while relaxation back to low spin state is aided by alternating the substrate magnetization.

Engineering magnetism at functional oxides interfaces: manganites and beyond.

The family of transition metal oxides (TMOs) is a large class of magnetic materials that has been intensively studied due to the rich physics involved as well as the promising potential applications in next generation electronic devices. In TMOs, the spin, charge, orbital and lattice are strongly coupled, and significant advances have been achieved to engineer the magnetism by different routes that manipulate these degrees of freedom. The family of manganites is a model system of strongly correlated magnetic TMOs.