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A single-feed dual-band dual-beam filtering patch antenna with both circular polarization (CP) and linear polarization (LP) properties is proposed in this letter. Dual bow-tie-shaped patches are used for concurrently achieving dual-beam and CP radiation in the lower passband. By employing L-shaped metal strips and a folded T-shaped stepped impedance feedline (FTSIF), the filtering response is introduced, simultaneously giving rise to the upper passband with LP operation. Additionally, through loading a T-shaped resonator, a deep radiation null (RN) is yielded between the two passbands. Consequently, dual-beam filtering responses with CP in the lower and LP in the upper passbands are, respectively, realized. For validation, a prototype is fabricated and tested. Two measured passbands operate at 5.30 GHz to 5.69 GHz and 6.11 GHz to 6.29 GHz, showing good dual-beam CP and LP radiation, respectively.

For many years, oil and natural gas geochemistry has been key to hydrocarbon exploration and exploitation in offshore China. Onshore oil fields have been thoroughly explored and exploited and have now entered the later stages of development. However, the oil and gas resources in the offshore basin of China are still abundant, and they have been relatively little explored, so they will be the main growth target for oil and gas production in the future. China has made many breakthroughs in offshore oil exploration in recent years. A large condensate field—Bozhong 19-6—has been discovered in the Bozhong Depression. Its main source rock is associated with algal blooming in the third member of the Shahejie Formation. The Baodao 21-1 gas field in the Qiongdongnan Basin shows clear signs of receiving terrestrial organic matter from the Yacheng and Lingshui formations. The first ultra-deep water and ultra-shallow gas, found in the Lingshui 36-1 gas field in the Qiongdongnan Basin, has thermogenetic and biogenetic origins. Well WY-1 in the Weixinan Depression marked the initiation of offshore shale oil exploration. Its sweet interval consists of two stable oil shale beds developed at the base and the top of the second member of the Liushagang Formation. However, samples from offshore exploration are often severely contaminated, and the corresponding data can be seriously distorted, which yields fewer core and more cutting samples. Therefore, it is necessary to thoroughly screen test data and to apply decontamination treatment and data correction to contaminated samples. The success rate of offshore exploration usually relies on the accurate prediction of source kitchens. Reservoir geochemistry thus has great significance for the future, as source input geochemical information can be used to trace materials backwards, and source kitchens can be predicted, when geochemistry is combined with enrichment and development models of source rocks and geophysical data.

To address the global challenges associated with energy and environmental concerns, the design, development, and application of novel materials have emerged as pivotal drivers. Notably, high-entropy perovskite oxides (HEPOs) amalgamate the merits of both perovskite oxides and high-entropy materials, presenting significant potential in addressing numerous critical issues in energy and environment. This review delves into the recent advancements of HEPOs in these domains. Firstly, it provides an overview of prevalent synthesis techniques for HEPOs, alongside two emerging low-temperature, eco-friendly methods. Subsequently, current strategies to optimize the performance of HEPOs are summarized from three perspectives: compositional engineering, morphological engineering, and structural engineering. The review further underscores their applications in areas such as lithium-ion batteries, supercapacitors, electrocatalysts, and solid oxide fuel cells. Based on this foundation, potential performance optimization strategies and potential application areas of HEPOs are discussed. Finally, it identifies challenges faced by further development of HEPOs in energy and environmental applications and provides an outlook on future developments.

Hardware data prefetching is a well-studied technique to bridge the processor-memory performance gap. Bit-pattern-based prefetchers are one of the most promising spatial data prefetchers that achieve substantial performance gains. In bit-pattern-based prefetchers, the region size is a crucial parameter, which denotes the memory size that can be recorded by a pattern or prefetched by a prediction. However, existing bit-pattern-based prefetchers only support one fixed region size. Our experiment shows that the fixed region size cannot meet the requirements for numerous applications and leads to suboptimal performance and high hardware overhead. In this article, we propose PARS, a pattern-aware spatial data prefetcher supporting multiple region sizes. The key idea of PARS is that it supports multiple region sizes, enabling it to simultaneously enhance application performance while reducing the hardware overhead. Moreover, PARS supports dynamically switching appropriate region sizes for different patterns through an adaptive RS-switching mechanism. We evaluated PARS on numerous workloads and results show that PARS provides an average performance improvement of 40.6% over a baseline with no data prefetchers and outperforms the two state-of-the-art prefetchers Bingo by 2.1% (up to 24.4%) and Pythia by 3.9% (up to 111.2%) in the single-core system. In the four-core system, PARS outperforms Bingo by 5.0% (up to 66.0%) and Pythia by 5.4% (up to 177.9%).

The advantages of ammonia as a hydrogen carrier have led to proposals for on-site hydrogen production through its decomposition. Rapid cold start of ammonia decomposition is crucial for applications such as ammonia-powered vehicles, but conventional heating methods are challenged by the high decomposition temperature of ammonia. In this study, we successfully achieved the rapid cold start of ammonia decomposition using Co nanoparticle catalysts driven by magnetic induction heating, demonstrating excellent catalytic performance and stability. The magnetic induction heating-driven ammonia decomposition system was integrated with a hydrogen fuel cell, proving its ability to achieve the cold start of ammonia decomposition within 10 s, as demonstrated by comparative experiments using 75% H2-25% N2from a gas cylinder as the control. This study provides a deeper understanding of hysteresis heating catalysis, promoting the practical use of ammonia as a hydrogen carrier for rapid hydrogen production in the energy industry.

Developing high-performance electrodes for flexible antifreezing energy storage devices has been a significant challenge with the increasing demand for portable components. In this work, Cr-substituted SrCoO3-δperovskites were first proposed as potential low-temperature supercapacitor electrode materials. The high-valence Cr6+([Ne]3s23p6) substitution favors a high-spin state of Co ions with enhanced electronic repulsion effect, ultimately forming a stable cubic structure with high conductivity. Accordingly, the modification strategies of SrCoO3through the p6 configuration cation substitution have been improved. As a result, the asymmetric SrCo0.95Cr0.05O3-δ@CC//PPy@CC device exhibited a high energy density of 44.90 Wh kg–1at 902.01 W kg–1and maintained a 95.8% specific capacitance after 10,000 cycles, demonstrating an ultralong cyclic stability. The dramatically improved electrochemical performance was attributed to the stabilized crystal structure, increased oxygen vacancy, and accelerated oxygen diffusion rate. Furthermore, a quasi-solid-state supercapacitor with ethylene glycol (EG)-modified KOH/PVA organohydrogel electrolyte was developed through an advance in situ-integrated strategy. After bending at 180° for 1000 cycles, only a 9.7% capacity decay was observed. Even under −40 °C, the supercapacitor has a large energy density of 46.94 μWh cm–2. The present work represents the initial investigation into utilizing perovskite materials for antifreezing energy storage device, thereby confirming their potential application as low-temperature electronic components.

A miniaturized dual-band dual-beam filtering patch antenna with orthogonal beam pointing is proposed. By using a cross-shaped feedline with two pairs of orthogonal common-mode (CM) currents, TM02 and TM20 modes are excited with suppression of adjacent TM10 and TM12 modes, and radiation null 1 (RN1) is introduced in both polarizations. Due to far-field nulls of orthogonal dual-beam patterns, intrinsic radiation null 1 (RN $_{\mathrm {i}1}$ ) and RN $_{\mathrm {i}2}$ are generated. With miniaturization, by etching periodic short slots, RN $_{\mathrm {i}3}$ related to the high-order harmonic can be used, its frequency can be significantly controlled, and the radiation pattern is reshaped to effectively improve the rejection at RN $_{\mathrm {i}3}$ in $x$ -polarization. To ensure high selectivity at each sideband while remaining compact, nested two quasi-circular loops (QCLs) and a cross-shaped metal strip (CSMS) are employed to create RN2–RN4 in both polarizations. Thus, a total of eleven RNs are yielded, aching high selectivity and deep stopband rejection. With a small size of $0.40\lambda _{0} \times 0.44\lambda _{0} \times 0.028\lambda _{0}$ , a prototype is fabricated and tested. Measured results show that dual beams in 5.3–5.53 GHz point toward the $x$ -axis direction, while dual beams in 6.34–6.66 GHz point toward the $y$ -axis direction, satisfying the requirements of point-to-multipoint scenarios providing different wireless services in orthogonal orientations.

Ternary hierarchical Fe3O4@C@MoS2composites and binary hierarchical Fe3O4@C composites were successfully fabricated by a modified mixed solvothermal method, a self-oxidation polymerization method, and a hydrothermal process. Their magnetic properties and microwave absorption performance were investigated. Dual resonance behavior was observed in the Fe3O4@C@MoS2composites. One of the resonances was attributed to natural resonance with a resonance frequency of 2.58 GHz, which was much higher than that for Fe3O4bulk (1.5 GHz). The other originated from the superparamagnetic/ferromagnetic relaxation with a resonance frequency of 12.45 GHz. The minimum reflection loss (RLmin) reached −64.30 dB with a matched thickness of 2.24 mm at 11.64 GHz, and the maximum effective absorption bandwidth (EABmax) covered 6.39 GHz with a matched thickness of 1.89 mm. In addition, the maximum Radar cross section (RCS) reduction value reached 31.90 dB m2at a scattering angle of 0°. Electron holography analysis confirmed a dense magnetic absorption network in the Fe3O4@C@MoS2composites. The boost in microwave absorption performance was caused by the synergistic effects of magnetic and dielectric properties owing to the ternary hierarchical structure, shape magnetic anisotropy, and incorporation of 1T/2H MoS2. Besides, the binary hierarchical Fe3O4@C composites also exhibited good absorbing performance caused by natural resonance, with an RLminof −52.90 dB at 5.80 mm, an EABmaxof 5.98 GHz at 3.38 mm, and a relatively high RCS reduction value of 13.04 dB m2at θ = 20°. This work paves the way for designing multicomponent hierarchical absorbers with broadband and intensive microwave absorption.

In this study, guar gum fibers were obtained by wet spinning, in which epichlorohydrin (ECH) and calcium chloride (CaCl2) were used as the cross-linking agent and metal complexing agent, respectively. The fibers’ chemical structure, morphology, crystallinity, and thermal and mechanical properties were analyzed by Fourier infrared spectroscopy, scanning electron microscopy, and so forth. The results showed that ECH reacted with guar gum and formed ether bonds. Meanwhile, ECH can effectively increase the number of cross-linking points and improve the mechanical properties of the fibers. When the ECH content was 12% (w/w), the breaking strength could reach 2.4 cN/dtex. The conductivity of MC-GG fibers varied with the relative humidity and could reach 2.845 × 10–2S/cm at maximum. Meanwhile, the contact angle of MC-GG fibers was 33°, indicating that the fibers had good hydrophilicity and humidity response ability and had excellent potential in the field of smart fabrics.

With new sulphur oxides emission limits carried out in 2020, multiple desulphurisation methods have been proposed. The main desulphurisation scrubber systems were chosen and investigated using life cycle assessment. The whole system life is divided into the construction and operational phases. Three different systems classified by desulphurisers, namely, seawater, NaOH, and Mg-based systems, were modelled in GaBi software. Moreover, environmental, economic and energy aspects (3E model) were introduced for further analysis. Through this study, some conclusions have been drawn. As for the environmental aspect, the seawater system has the most pleasing performance since the primary emissions come from 1.24E+03 kg CO2and 1.48E+01 kg chloride. The NaOH system causes 1000 times more emissions than the seawater. The Mg-based system has less pollution than the NaOH system, with 5.86E+06kg CO2and 3.86E+03 kg chloride. The economic aspect is divided into capital expenditure (CapEx) and operational expenditure (OpEx) to estimate disbursement. The seawater system also has the most favourable cost appearance, which takes 1.7 million dollars without extra desulphuriser expenses, based on 10MW engine flue gas treatment. The next is the Mg-based system, which cost 2 million dollars in CapEx and $ 1200/year in OpEx for the desulphuriser. NaOH uses about 2.5 million dollars for construction and $ 30000/year in desulphuriser. As for the energy aspect, the seawater and Mg-based systems use less non-renewable energy than the NaOH system in the construction phase. In conclusion, the seawater system shows the best performance and could be an alternative in SOx control technologies. This study sheds light on the comprehensive evaluation of marine environmental protection technologies for further optimisation.

Background: We research the binding function proteins in Elymus nutans. Recognition for proteins is essential for study of biology. Machine learning methods have been widely used for the prediction of proteins. Methods: We used BLAST software for the function annotations of Elymus nutans. Besides, we used machine learning methods to recognize proteins which are not annotated by the software. In the process, we focused on identifying the proteins with binding functions. In our research, features are extracted by four algorithms, and then selected by mutual information estimator. Here three classifiers are constructed based on K-nearest neighbour algorithm and gradient boosting algorithm. Results and Conclusion: Experimental results show that there are 848 proteins with ATP binding function, 113 proteins with heme binding function, 315 proteins with zinc-ion binding function, 135 proteins with GTP binding function and 21 proteins with ADP binding function. Furthermore, we have successfully predicted the functions of 10 special protein sequences whose function annotations cannot be obtained by making sequence alignment with seven famous protein databases. Among them, seven sequences have ATP binding functions, one sequence has heme binding function, one sequence has zinc-ion binding function and the other one has GTP binding function.

Traditional protective structure optimization design processes do not often consider uncertainty factors, such as structural dimensions. This causes the optimization results to be near the constraint boundaries and leads to insufficient reliability and robustness of the design. In this study, an accurate finite element model was obtained for armored vehicle protective component design through a physical explosion test and a simulation of the whole vehicle. Subsequently, uncertainty optimization, reliability optimization, and robustness optimization were introduced into the optimization process, and the uncertainty optimization results were analyzed and compared for different constraint degrees. The results show that the reliability of the results obtained from traditional deterministic optimization was low. Introducing the reliability optimization and robustness optimization design methods into the protective component design significantly improved the reliability of the protective component results.

In the process of military missions, special vehicles often encounter shallow buried charge threats that will greatly affect the safety of the occupants. To study the integrated effects of shallow buried charge detonation point, height-to-diameter ratio, burial inclination, weight, and other key parameters on the lower limb injuries of occupant, this study was based on the special body of a shallow buried explosive test and numerical calculation methods. The reliability of the numerical model and the load effect mechanism of the shallow burial charge were studied. Based on this, the lower limb injuries response law of occupant was analyzed with respect to each parameter. The results showed that the bottom charge load mainly came from two-stage ejection loading, in which the first stage was a strong load with short-duration local impact loading and the second stage was a weak load with long-duration extended range loading. By comparing the lower limb injury response of occupant under different charge parameters, we found that the weight of charge had the greatest effect on the extent of occupant injury, followed by the height-to-diameter ratio and burial inclination, while the detonation position had a relatively small effect on the injury magnitude. Finally, a comprehensive prediction model of the lower limb injuries of occupant was obtained by using the Latin hypercube sampling method and the least-squares method, and it was verified that the model had a good matching accuracy.

All-inorganic two-dimensional (2D) CsSnI3nanosheets exhibit reduced biotoxicity, high mobility, and suitable band gap, making them highly promising for nanoelectronic or optoelectronic applications. However, the synthesis of 2D CsSnI3nanosheets remains challenging. In this study, 2D CsSnI3nanosheets were successfully synthesized by using a space-confined chemical vapor deposition (CVD) method for the first time. The average thickness and lateral size of 2D CsSnI3nanosheets were well-controlled by adjusting the gap distance within the confined space and the growth temperature. This approach also facilitated in situ construction of CsSnI3-based vertical heterostructures by directly growing CsSnI3nanosheets on the surface of target WSe2. The space-confined CVD growth of lead-free perovskite nanosheets will provide more options for the development of low-dimensional perovskite-based optoelectronic devices.

DeepKa is a deep-learning-based protein pKapredictor proposed in our previous work. In this study, a web server was developed that enables online protein pKaprediction driven by DeepKa. The web server provides a user-friendly interface where a single step of entering a valid PDB code or uploading a PDB format file is required to submit a job. Two case studies have been attached in order to explain how pKa’s calculated by the web server could be utilized by users. Finally, combining the web server with post processing as described in case studies, this work suggests a quick workflow of investigating the relationship between protein structure and function that are pH dependent. The web server of DeepKa is freely available at http://www.computbiophys.com/DeepKa/main.

The defective structure and high oxygen vacancy concentration of SrFeO3−δperovskite enable fast ion-electron transport, but its low conductivity still hinders the high electrochemical performance. Herein, to enhance the conductivity of SrFeO3−δ-based electrodes, polypyrrole-modified SrFeO3−δperovskite on carbon cloth (PPy@SFO@CC) has been successfully fabricated by electrodeposition of polypyrrole (PPy) on the surface of SFO@CC. The optimal PPy700@SFO@CC electrode exhibits a specific capacitance of 421 F g–1at 1 A g–1. It was found that the outside PPy layer not only accelerates the electron transport and ion diffusion but also creates more oxygen vacancies in SrFeO3−δ, enhancing the charge storage performance significantly. Moreover, the NiCo2O4@CC//PPy700@SFO@CC device maintains a specific capacitance of 63.6% after 3000 cycles, which is ascribed to the weak adhesion forces between the active materials and carbon cloth. Finally, the all-solid-state flexible supercapacitor NiCo2O4@CC//PPy700@SFO@CC is constructed with PVA-KOH as the solid electrolyte, delivering an energy density of 16.9 W h kg–1at a power density of 984 W kg–1. The flexible supercapacitor retains 69% of its specific capacitance after 1000 bending and folding times, demonstrating a certain degree of foldability. The present study opens new avenues for perovskite oxide-based flexible all-solid-state supercapacitors.

For many petroleum production plays with large amounts of natural gas produced, their hydrocarbon accumulation processes have been reported to be commonly involved with gas-washing. The gas generation intensity of the Xihu Sag, East China Sea Basin is up to 6 × 106 t/km2, which is the primary driving force for gas-washing to occur. 18 oils and 20 gas samples produced from the Eocene – Oligocene sandstone reservoirs in the Xihu Sag has been geochemically characterized to delineate the controlling factor of the gas-washing and in turn better understand the hydrocarbon accumulation mechanism of the study area. The results show that the natural gas is primarily mature-highly mature coal-type gas based on their carbon isotope characteristics. The oils are believed to belong to a same oil family with a similar thermal maturity and have been gas-washed based on either their molecular fingerprints or other geochemical characteristics. The high toluene/n-heptane ratio (Tol/nC7) and high n-alkane mass depletion (Q) of the oils further indicate the occurrence of gas washing. A good correlation between either the reservoir depth or the gas generation intensity of the source kitchen and the n-alkane mass depletion of the crude oil indicate reservoir depth and gas generation intensity are the two primary controlling factors on the gas washing of the study area. In order to further delineate the effects of evaporative fractionation or migration fractionation on the hydrocarbon reservoir, we introduced a new cross plot of n-alkanes mass depletion (Q) versus adamantane/diamantine (A/D) to type the oils related to the gas washing in the study area. The meaning of this paper for the exploration of oil and gas resources will be related to the understanding of different gas washing mechanism, so as to further enhance the exploration efficiency.

High energy consumption is the bottleneck in advanced oxidation processes (AOPs) for applying in eliminating refractory organic contaminants. Fenton catalysis is deemed to be the promising technology of AOPs to produce super-active hydroxyl radical ( ·OH) for tackling serious water environment pollution issues. Here, magnetic mesoporous sulfur-doped ferric oxide (PS-Fe) composite, prepared through simple co-precipitation method, was creatively introduced to activate hydrogen peroxide (H2O2) to generate ·OH for degrading emerging antibiotic moxifloxacin (MOX). The catalytic activity of PS-Fe was significantly elevated by sulfurization to achieve a degradation efficiency of 97 % and total organic carbon removal exceeding 44 % (within 30 min). Besides, we investigated the effects of catalyst dosage and H2O2concentration, initial pH value, temperature, and humic acid concentration on MOX degradation. Quenching experiments results indicate that ·OH, O2·–, and 1O2participated in the degradation process of MOX, and ·OH plays the predominant role. Additionally, possible activation mechanism is proposed and possible reaction intermediates are speculated. This work can offer a novel and reasonable interpretation for designing heterogeneous iron-based materials in activating H2O2to degrade pollutants.

pH regulates protein structures and the associated functions in many biological processes via protonation and deprotonation of ionizable side chains where the titration equilibria are determined by pKa’s. To accelerate pH-dependent molecular mechanism research in the life sciences or industrial protein and drug designs, fast and accurate pKaprediction is crucial. Here we present a theoretical pKadata set PHMD549, which was successfully applied to four distinct machine learning methods, including DeepKa, which was proposed in our previous work. To reach a valid comparison, EXP67S was selected as the test set. Encouragingly, DeepKa was improved significantly and outperforms other state-of-the-art methods, except for the constant-pH molecular dynamics, which was utilized to create PHMD549. More importantly, DeepKa reproduced experimental pKaorders of acidic dyads in five enzyme catalytic sites. Apart from structural proteins, DeepKa was found applicable to intrinsically disordered peptides. Further, in combination with solvent exposures, it is revealed that DeepKa offers the most accurate prediction under the challenging circumstance that hydrogen bonding or salt bridge interaction is partly compensated by desolvation for a buried side chain. Finally, our benchmark data qualify PHMD549 and EXP67S as the basis for future developments of protein pKaprediction tools driven by artificial intelligence. In addition, DeepKa built on PHMD549 has been proven an efficient protein pKapredictor and thus can be applied immediately to, for example, pKadatabase construction, protein design, drug discovery, and so on.

The self-supported nanoflake-shaped Bi2Se2was synthesized with the convenient method of microwave reaction, and adhered to the flexible carbon fiber felt. A series of electrochemical tests indicate that capacitance of Bi2Se2/CF electrode can reach 877.0 C g−1(1 A g−1). Assembled by ligninbased carbon materials and Bi2Se2/CF electrode, the asymmetric capacitor has the energy density of 20.83 W h Kg−1while the power density can reach 749.9 W kg−1. After circulating for 2000 times under 3 A g−1, the remaining capacitance retention reaches 81% of the initial one.

Capacity limit is a bottleneck for broader applications of blockchain systems. Scaling up capacity while preserving security and decentralization are major challenges in blockchain infrastructure design. In this paper, we design a proof of work-based mechanism by endowing directed acyclic graphs (DAG) with a novel structure so that peers can reach consensus at a large scale. At a high level, we break large blocks into smaller ones to improve utilization of broadcast network and embed a Nakamoto chain inside the DAG in a decent way to ensure security. We further exploit the DAG structure and design a mempool transaction assignment method. The method reduces the probability that a transaction is processed by multiple miners and hence improves processing efficiency. Without sacrificing security and decentralization, our design significant scales up capacity and also addresses important issues such as high latency and mining power concentration in existing blockchain systems.