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Designing g-C3N4-based nanostructured photocatalysts is crucial to boosting their application in advancing clean energy and sustainable environmental solutions. In this study, cyano groups and amorphous carbon self-modified P-doped g-C3N4 (PCNx) photocatalysts were designed and prepared by one-pot calcination. Melamine phosphate was employed as a multifunctional precursor to simultaneously achieve P-doping and amorphous carbon/cyano group self-modification in the g-C3N4 photocatalyst. The molar ratio of urea to melamine phosphate regulates the content of amorphous carbon and cyano groups, which further enhances the conductivity of g-C3N4. Due to the high conductivity of amorphous carbon and cyano groups, the charge transfer process was further accelerated. As a result, the optimized P-doping and amorphous carbon/cyano-group in PCN2 photocatalyst led to an excellent H2 production rate of 157.86 µmol·g−1·h−1 under visible light, which is approximately 2.4 times and 3 times higher than those of CN and PCN. The work developed an alternative strategy for the construction of highly efficient g-C3N4-based photocatalysts. [ABSTRACT FROM AUTHOR]

Main group Bi‐based materials have gained popularity as N2 reduction reaction (NRR) photo/electrocatalysts due to their ability to inhibit competitive H2 evolution reactions (HER) and the unique N2 adsorption activities. The introduction of defects in Bi‐based catalysts represents a highly effective strategy for enhancing light absorption, promoting efficient separation of photogenerated carriers, optimizing the activity of free radicals, regulating electronic structure, and improving catalytic performance. In this review, we outline the various applications of state of the defect engineering in Bi‐based catalysts and elucidate the impact of vacancies on NRR performance. In particular, the types of defects, methods of defects tailoring, advanced characterization techniques, as well as the Bi‐based catalysts with abundant defects and their corresponding catalytic behavior in NRR were elucidated in detail. Finally, the main challenges and opportunities for future development of defective Bi‐based NRR catalysts are discussed, which provides a comprehensive theoretical guidance for this field. [ABSTRACT FROM AUTHOR]

Development of highly active and selective electrocatalysts for the reduction of nitrate (NO3–) to ammonia is critical for the production of green ammonia. Herein, we designed and synthesized NiMoO4 nanocubes as an efficient electrocatalyst for nitrate reduction using deep eutectic solvents (DESs) as synthesis media. By constructing Mo and Ni dual-active sites, Mo facilitates NO3– adsorption/association, and Ni acts as an active hydrogen (*H) donating center. The amount and destination of *H can be regulated, which can effectively enhance the activity of the NO3– reduction to NH3 reaction (NO3–RR). The optimized sample possessed excellent NO3–RR activity. An NH3–N selectivity of up to 96.94% and a Faraday efficiency of up to 96.13% can be achieved at −0.4 V in a neutral solution. The catalytic NO3–RR mechanism was also investigated by density functional theory (DFT) calculations. This dual-active site electrocatalyst provides an alternative idea for the synthesis and application of high-performance NO3–RR catalysts. [ABSTRACT FROM AUTHOR]

Designing approaches to synthesizing nanostructure photocatalysts is crucial to boosting applications in photocatalytic H2 production. Herein, a Z-scheme p–n heterojunction for photocatalytic H2 production was designed and constructed by decorating p-type CoP3 quantum dots on n-type CdZnS nanorods. The flower-like CoP3/CdZnS nanorod assembly benefits from light absorption and full contact with the solution. An internal electric field forms at the interface of the p–n junction, which provides a Z-scheme charge transport path for efficient migration and separation of photogenerated charges. In result, the hydrogen production rate of the CoP3/CdZnS p–n junction is 33 times that of CdZnS. The study provided a novel approach to the synthesis of self-assembled nanostructures of quantum dots on nanorod assemblies that have important applications in photocatalysis for energy conversion. [ABSTRACT FROM AUTHOR]

During sonar detection, the fuzzy function of hyperbolic frequency modulation (HFM) in the waveform of active signal is in the shape of a "oblique blade," which leads to the coupling characteristics of its fuzzy function in the time dimension and frequency dimension. Doppler causes a frequency shift in the frequency dimension and a time delay in the time dimension, which makes it impossible for a single HFM signal to measure speed accurately. However, the time delay caused by the same moving target to HFM signals with different frequency bands and different pulse widths is also different. A velocity measurement method combining HFM signals (VCH) is proposed, which employs the time delay correlation between the combined HFM signals to achieve the target distance and speed. In the VCH method, the echo signal is no longer matched and filtered as a whole but is divided into two channels and matched and filtered separately. And then, the combined HFM signals are used to obtain the distance and speed of the target. Extensive simulation results show that the proposed method can estimate the distance and speed of moving targets accurately, and it has reference value for engineering application. [ABSTRACT FROM AUTHOR]

Developing a highly efficient catalyst for the oxygen evolution reaction (OER) is of great significance for its application in electrocatalytic water splitting. Herein, a solid–solid transformation strategy has been developed to construct sulfur-doped Ni0.5Co0.5Fe2O4 spinel porous single-crystal nanosheet arrays on nickel foam (S-NCFO/NF). The single-crystalline nanosheet self-assembled nanostructures can provide fast charge transfer channels. With the effect of S-doping, a distorted/incomplete octahedral structure nanosheet can be formed. The unique porous S-NCFO nanosheets can provide a large number of active sites and sufficiently contact the electrolyte to adsorb OH– and desorb O2. By virtue of the porous single-crystal nanosheet, sulfur-doped spinel structure, and the unique self-assembled nanosheet configurations, the S-NCFO/NF electrode exhibits enhanced OER performance with low overpotentials at 100 mA cm–2 of 300 mV in 1 M KOH and 317 mV in 1 M KOH + 0.5 M NaCl. The synthesis strategy provides insight for the preparation and application of self-assembled nanostructures in electrocatalytic seawater splitting. [ABSTRACT FROM AUTHOR]

The 1.43" hybrid wearable AMOLED display (HWAD) had been developed based on low‐temperature polycrystalline silicon (LTPS) and thin‐film encapsulation (TFE) techniques, which was integrated touch and display functionalities with one driver IC. The 1.43" HWAD border was similar to flexible products, but less than rigid ones above 20%. Meanwhile, the ultra‐thin stack‐up module thickness was also close to that of flexible ones, but reduced about 31.4% compared to traditional rigid display. HWAD utilized a new pixel compensation circuit and a novel compensation algorithm, eventually achieved a flicker indicator FMA value of <3% in 5Hz AOD mode. The logic power consumption of the smart watch in 5Hz AOD model is reduced about 35% compared with the one in 30Hz. The novel HWAD aggregated the advantages of flexible and rigid displays with low process costs. The novel high‐performance HWAD had significant market application prospect. [ABSTRACT FROM AUTHOR]

The channel in the marine environment is a time-varying and space-varying channel. Pulse-truncated continuous wave (PCW) speed measurement is often used in sonar, but the instability effect of PCW signal in the channel limits the effectiveness of speed measurement. Hyperbolic frequency modulation (HFM) signal is insensitive to Doppler; therefore, HFM signals are widely used in ranging and velocity measurement of sonar and radar. However, due to the filtering effect of the marine environment, the HFM signal of a single frequency band may cause excessive transmission loss, and the echo energy may be too weak to detect the target. Based on the analysis of the influence of speed on the distance measurement of HFM signal, a pulse sequence method based on HFM for speed measurement (PHS) is proposed, which uses HFM signals of different frequency bands and pulse widths in the pulse sequence to perform speed measurement. Extensive simulation results show that PHS method not only guarantees the speed measurement but also makes full use of the energy of the HFM sequence to improve the accuracy of the distance measurement. And PHS method is valuable to the practical application of engineering. [ABSTRACT FROM AUTHOR]

Designing and developing low-cost, high-efficiency catalysts to reduce the overpotential and improve the efficiency of hydrogen energy conversion are current research hotspots. In this work, CoNi2S4 nanosheets on carbon cloth (CoNi2S4/CC) were prepared to use one-step pyrolysis of the deep eutectic solvent (DES) precursor. It is feasible to cover carbon cloth evenly with DES due to its intense adherence and liquid conditions at ambient temperature. The CoNi2S4 nanosheet's coupling a CC substrate increases the electron transport efficiency and prevents the catalyst from agglomeration and corrosion during catalytic processes. Self-supported CoNi2S4/CC exhibited excellent hydrogen evolution reaction (155 mV at 50 mA cm–2 and 30 mV at 10 mA cm–2) and oxygen evolution reaction (372 mV at 100 mA cm–2 and 153 mV at 10 mA cm–2) activities. Serving as a bifunctional catalyst, CoNi2S4/CC requires cell voltages of only 1.42 and 1.86 V to achieve 10 mA cm–2 and 100 mA cm–2 current density, respectively, in overall water splitting in 1.0 M KOH, exhibiting extraordinary durability. Moreover, CoNi2S4/CC exhibits excellent overall water-splitting activity in simulated seawater, which significantly advances the development of seawater electrolysis. [ABSTRACT FROM AUTHOR]

In recent years, with the frequent crises of trust in the food industry, food safety issues have become an issue of particular concern to consumers. The traditional agricultural food logistics and transportation model can no longer guarantee the traceability of food safety information, and it is particularly important to establish an effective traceability system. Therefore, a traceability system is applied as a tool to assist in the assurance of food safety and quality, as well as to achieve consumer confidence. Blockchain is a new decentralized infrastructure and distributed computing paradigm that has gradually emerged. Blockchain has the characteristics of decentralization, immutable information and trustworthiness. When blockchain is applied to the traceability system of agricultural products, the quality of agricultural products will be well guaranteed. This article aims to provide a comprehensive review of the recent research efforts on traceability in agricultural products based on blockchain technology. First, the method of content analysis used in this article to sort out the papers is introduced. Second, the background concepts of blockchain and the key technologies are presented. Thirdly, the traceability applications based on blockchain technology for agricultural products are described in detail. Finally, we expand on the current trends and provide new perspectives pertaining to this exciting application of this field. [ABSTRACT FROM AUTHOR]

Atomically precise nanoclusters (NCs) provide opportunities for correlating the structure and electrocatalytic properties at atomic level. Herein, we report the single-atom doping effect and ligand effect on CO2 electroreduction (eCO2RR) by comparing monogold-doped Au1Cu24 and homocopper Cu25 NCs protected by triphenylphosphine or/and tris(4-fluorophenyl)phosphine. Catalytic results revealed that the electronic distribution of Cu25 NCs is enormously contracted by doping Au atoms, entitling it to exhibit the unique inhibition of hydrogen evolution reaction. And the inductive effect of ligand strongly favors the formation of formate in eCO2RR. Overall, this work will provide guidance for the rational design of the copper-based catalysts in the eCO2RR. Tuning the metal core and ligand environment of atomically precise nanoclusters enables the correlation of structural and electrocatalytic properties at an atomic level. Here, single-atom doping and ligand tuning of atomically precise copper clusters is shown to be an effective route to tuning CO2 electroreduction activity and selectivity. [ABSTRACT FROM AUTHOR]

In this brief, we consider the mean-field type H − index problem for stochastic Markovian jump systems. A sufficient condition is derived for stochastic Markovian jump systems with (x , u) -dependent noise based on generalized differential Riccati equations. Especially for stochastic Markovian jump systems with only x-dependent noise, a sufficient and necessary condition is developed to characterize H − index larger than some ξ > 0 . Finally, a numerical example is addressed to verify the effectiveness of our obtained results. [ABSTRACT FROM AUTHOR]

Synthetic protocols to generate well-integrated frameworks of known composition are important for the rational design of advanced materials. 3D CeO2/NiO hierarchical assemblies were designed and constructed with 2D CeO2/NiO heterostructures as building blocks consisting of NiO nanosheets wrapped with CeO2 ultrathin nanosheets on the surfaces. The growth process of the 2D CeO2/NiO heterostructure nanosheets and the 3D assemblies was described based on a domain-matching growth process. The CeO2/NiO assemblies exhibited superior catalytic properties for CO oxidation. A model of the structure–property relationships based on surface and interface structures is discussed. [ABSTRACT FROM AUTHOR]

Cooperative vehicle safety systems (CVSSs) rely on vehicular networking for broadcasting state information in order to track neighbors’ positions and, therefore, to predict potential collisions. In vehicular networking, a large number of vehicles compete for access to the limited channel resource, causing channel congestion. The vehicle tracking accuracy, which is the basis for CVSSs, therefore, can be heavily affected. Moreover, the available channel resources must be shared among vehicles in a fair way in order to maintain accurate tracking accuracy for each vehicle. To realize fair access to channel resources while maintaining an accurate tracking performance under conditions of dynamic vehicle density, in this paper, we present a distributed fair transmission rate control strategy, based on multi-agent model predictive control (MPC). We first propose a dynamic information dissemination rate model to capture the state information dissemination ability under conditions of dynamic vehicle density. Then, we present a multi-agent information dissemination model, in which each vehicle is controlled by a control agent that uses MPC and coordinates with its neighboring agents in order to determine its optimal transmission rate actions. We then design an augmented-Lagrangian-based distributed decision-making scheme to find the optimal transmission rate actions and, at the same time, reach an agreement on fair and efficient channel utilization among the vehicles. Simulation results confirm that the distributed transmission rate control strategy can guarantee fair access to channel resources while achieving the optimal vehicle tracking performance under conditions of dynamic vehicle density. [ABSTRACT FROM AUTHOR]

A graph is called Q-integral if its signless Laplacian spectrum consists of integers. In this paper, we characterize a class of k-cyclic graphs whose second smallest signless Laplacian eigenvalue is less than one. Using this result we determine all the Q-integral unicyclic, bicyclic and tricyclic graphs. [ABSTRACT FROM AUTHOR]

The crystal phase and morphology of MoO3 materials were precisely tuned under suitable synthetic conditions and mutual transformation of h-MoO3 and α-MoO3 was achieved via a facile hydrothermal method for the first time. The h-MoO3 microrods with a diameter of 0.5–1.6 μm and length of 2.2–6.1 μm were fabricated with the assistance of NaNO3 using α-MoO3 particles as the precursor. The transformation of h-MoO3 microrods to α-MoO3 nanobelts with a diameter of 150–430 nm and length of 2.1–14.5 μm occurred through hydrothermal techniques at higher temperature. Systematic studies of synthetic parameters revealed that the hexagonal h-MoO3 microrods formed at higher concentration of NaNO3, while h-MoO3 microrods vanished at higher temperature with prolonged time and α-MoO3 nanobelts were exclusively produced. The h-MoO3 microrods exhibited higher catalytic activity in photo-degradation of methylene blue than the α-MoO3 nanobelts. This is ascribed to the weaker fluorescence and reduced bandgap energy of the h-MoO3 microrods than those of the α-MoO3 nanobelts. [ABSTRACT FROM AUTHOR]

Cooperative vehicle safety systems rely on periodic broadcast of each vehicle's state information to track neighbors' positions and therefore to predict potential collisions. The shared wireless channel in such systems is heavily affected by vehicle density and even medium vehicle density can cause channel congestion. Moreover, the interference factors can also heavily degrade the performance of the network. The vehicle tracking accuracy is the basis of cooperative vehicle safety systems and is significantly affected by the network. In order to enhance the robustness of the network against dynamical vehicle density and interference, a dynamic feedback power control scheme based on proportional-integral-derivative control is proposed. In this scheme, a dynamic information dissemination model that captures the time-varying nature of vehicle density is firstly proposed. This model qualities the network performance in terms of tracking information dissemination rate under the effect of dynamic vehicle density. Then, a predictive model is presented to predict, in a dynamic and receding-horizon fashion, the ideal information dissemination rate by considering the dynamics of vehicle density. Finally, a feedback control model that adjusts the transmission power in a closed-loop fashion is introduced. The feedback control model integrates the ideal state of information dissemination rate and the current real state that may be affected by interference to generate real-time power control strategies. These power control strategies will guide the actual network to evolve towards the ideal information dissemination rate. Experimental results confirm that the proposed power control scheme can gain a high accurate vehicle tracking performance for each vehicle and is robust to variations of traffic situation. [ABSTRACT FROM AUTHOR]

Semimetal Bi and Sb thin films with novel hierarchical structures were synthesized on zinc substrate via a hydrothermal method. X-ray diffraction (XRD) analysis confirmed the formation of pure semimetals Bi and Sb. Scanning electron microscopy images showed that Bi films constructed with microtube arrays and hierarchical microspheres can be obtained selectively by altering the concentration of Bi3+ ions. The synthesized Sb films were constructed with bowl-shaped particles. The growth process of these semimetal architectures was briefly discussed. [ABSTRACT FROM AUTHOR]

In this study, a series of PbS polyhedra were synthesized through hydrothermal decomposition of the as-formed lead diethyldithiocarbamate (Pb-DDTC) single-source precursor in its precursor solution. Through extensive experiments, it was concluded that the amount of poly-(vinylpyrrolidone) (PVP), DDTC and the reaction time had major effects on the shapes of the as-synthesized PbS crystals. Sub-micro sized cuboctahedrons and cubes were selectively obtained by manipulating the concentration of PVP and the reaction time. Possible growth mechanism for the shape controlled synthesis of PbS crystals was briefly discussed. [ABSTRACT FROM AUTHOR]

A series of Bi2S3microstructures, including crepe paper flower-like structures, multibranched nanobelts, actinomorphic-flower-like 2-D assembled nanowire arrays, straw-tied-like nanowire arrays, and nanowires have been synthesized through facile decomposition of the as-formed bismuth diethyldithiocarbamate (Bi-DDTC) single-source precursor in its precursor solution. The morphologies and concentration and site of structure defects of the Bi2S3microstructures can be controlled by manipulating the concentration of Bi/DDTC and the reaction time. Possible growth mechanisms involving defect effects, oriented attachment and folding–splitting–attaching growth were proposed, which were responsible for morphology and structure evolution of various Bi2S3microstructures. [ABSTRACT FROM AUTHOR]

Mono-dispersed oxide and hydroxide nanoparticles have been synthesized through the solvothermal process in alcohol-water mixtures. The products were characterized by powder x-ray diffraction (XRD) and scanning electron microscopy (SEM). Plate-like nanoparticles are obtained for Bi2O2.33, Fe2O3, and Cd(OH)2, and spherical nanoparticles are obtained for SnO2. The growth mechanism for the mono-dispersed nanoparticles has been preliminarily discussed. [ABSTRACT FROM AUTHOR]

Uniform cubic-shaped PbTe and PbSe nanocrystals have been synthesized through the surfactant-assisted hydrothermal reaction between Pb(NO3)2 and Te or Se powders with hydrazine hydrate as reducing reagent. The products were characterized by powder x-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that the shapes of nanocubes are well controlled by using ethylenediaminetetraacetic acid as chelating reagent and in the presence of poly(vinyl-pyrrolidone). [ABSTRACT FROM AUTHOR]

Silver nanoshells on styrene–acrylic acid copolymer latex spheres (PSA) were deposited by an in situ chemical reduction method, ageing a colloid solution at 85 °C containing PSA latex, AgNO3, urotropine, and poly-(vinylpyrrolidone). SEM and TEM observations showed that the silver nanoshells were made of closely packed silver nanoparticles of different sizes and morphologies. UV–visible absorption spectra were recorded to investigate their optical properties. [ABSTRACT FROM AUTHOR]

Mono-dispersed Mg(OH)2 nanoflakelets have been prepared with the assistant of 4-(p-nitrophenylazo)resorcinol. The samples were characterized using XRD, TEM, and ED. Electron diffraction analysis showed that single crystalline nanoflakelets were obtained in hydrothermal process, and porous Mg(OH)2 nanosheets were prepared at lower temperature. Nitrogen adsorption isotherms show that the surface area of Mg(OH)2 nanosheets is 129 m2/g. Possible growth mechanism of the nanoflakelets is discussed. [ABSTRACT FROM AUTHOR]