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Reservoir transformation is essential for developing gas hydrate reservoirs. Predicting sediment brittleness is key to optimizing drilling design and evaluating engineering sweet spots. Constructing a brittleness index reflecting the brittle mineral content of a rock based on elastic parameters and predicting it using seismic data is a feasible solution for assessing reservoir brittleness. In addition, the elastic brittleness index can characterize the effect of complex pore types, fractures and pore fillings on rock brittleness. With the shallow hydrate reservoir in the sea as the research target. First, a novel brittleness index characterized by multiplying the Lamé parameter (λ$\lambda $) by Poisson's ratio (σ$\sigma $) is proposed. Its superiority in indicating brittle mineral content is verified by a rock‐physics model. Second, a reflection coefficient approximation equation including the novel brittleness index is derived, enabling direct estimation of reservoir brittleness from seismic data. The new brittleness index has proven to better reflect brittle mineral content and effectively indicate the high brittleness characteristics of hydrate reservoirs. The accuracy of the proposed approximate equation is verified by a layered medium model, and the viability of predicting the new brittleness index using seismic data is also theoretically supported by the model test. Finally, the proposed method has obtained favourable results in the application of hydrate work area data collected at the South China Sea, confirming its availability and practicality. [ABSTRACT FROM AUTHOR]

The increase in port scale and business complexity has led to an increased demand for comprehensive and lean control on ports. The current operation mode is facing the bottleneck of the increasingly significant production efficiency and performance. Digital twin (DT) technology realizes holographic visual management and control patterns using cyber-physical fusion and promotes the transformation of a port to an intelligent operation mode. In this paper, the framework of a digital twin application system is proposed based on the analysis of business characteristics of large-scale comprehensive ports. Construction methods and technologies such as digital twin modeling, global ubiquitous perception, data mapping, and model fusion are analyzed. With regard to the construction needs of Qingdao Port's digital twin system, this paper presents a case study and illustrates the overall design process and function of the digital twin system for typical terminals. The system realizes the intelligent operation of the port with the core functions of three-dimensional visual monitoring and optimal dispatching based on real-time perception data. This paper serves as a feasible reference for future intelligent development of large ports and the application of digital twin technology. [ABSTRACT FROM AUTHOR]

Since plant diseases occurring during the growth process are a significant factor leading to the decline in both yield and quality, the classification and detection of plant leaf diseases, followed by timely prevention and control measures, are crucial for safeguarding plant productivity and quality. As the traditional convolutional neural network structure cannot effectively recognize similar plant leaf diseases, in order to more accurately identify the diseases on plant leaves, this paper proposes an effective plant disease image recognition method aECA-ResNet34. This method is based on ResNet34, and in the first and the last layers of this network, respectively, we add this paper's improved aECAnet with the symmetric structure. aECA-ResNet34 is compared with different plant disease classification models on the peanut dataset constructed in this paper and the open-source PlantVillage dataset. The experimental results show that the aECA-ResNet34 model proposed in this paper has higher accuracy, better performance, and better robustness. The results show that the aECA-ResNet34 model proposed in this paper is able to recognize diseases of multiple plant leaves very accurately. [ABSTRACT FROM AUTHOR]

The dynamic economic dispatch (DED) problem is a typical complex constrained optimization problem with non-smooth, nonlinear, and nonconvex characteristics, especially considering practical situations such as valve point effects and transmission losses, and its objective is to minimize the total fuel costs and total carbon emissions of generating units during the dispatch cycle while satisfying a series of equality and inequality constraints. For the challenging DED problem, a model of a dynamic economic dispatch problem considering fuel costs is first established, and then an improved grey wolf optimization algorithm (IGWO) is proposed, in which the exploitation and exploration capability of the original grey wolf optimization algorithm (GWO) is enhanced by initializing the population with a chaotic algorithm and introducing a nonlinear convergence factor to improve weights. Furthermore, a simple and effective constraint-handling method is proposed for the infeasible solutions. The performance of the IGWO is tested with eight benchmark functions selected and compared with other commonly used algorithms. Finally, the IGWO is utilized for three different scales of DED cases, and compared with existing methods in the literature. The results show that the proposed IGWO has a faster convergence rate and better global optimization capabilities, and effectively reduces the fuel costs of the units, thus proving the effectiveness of IGWO. [ABSTRACT FROM AUTHOR]

Ceramic structures have attracted extensive attention due to their excellent high temperature properties, low density and function application after structural design. Herein, six different ceramic lattices based on struts and triply periodic minimal surfaces (TPMS) sheet lattices were designed and fabricated by digital light processing (DLP) using polymer precursor. The effects of unit cell size, relative density and other parameters on the compressive and shear properties of the structure were studied in detail. A structure optimized from Gyroid was put forward, which realized excellent mechanical properties under 15% low relative density (0.25 g/cm3). Results also suggested that the TPMS sheet lattices were more suitable for bearing under low relative density and the struts-based lattices were more sensitive to the parameters change, 20% is an important node where the mechanical properties of the structure decline significantly. Design of the structure in the loading direction can effectively improve the mechanical properties. This study provides a new basis for structural design under low relative density, which will aid in the further improvement of traditional structures and the development of the application of ceramic materials in mechanical structures. [ABSTRACT FROM AUTHOR]

The amphiboles from Kakanui and Arenal are two natural minerals that have been used worldwide as microanalytical reference materials, but their compositions and crystal structures are still poorly constrained. In this paper, we report new data on H2O and trace element mass fractions and single‐crystal structural refinement of these two amphiboles. H2O mass fractions of the Kakanui and Arenal amphiboles determined via Karl‐Fischer titration are 0.92 ± 0.18 (2s) and 1.56 ± 0.22% m/m (2s), respectively; these values estimated based on crystal‐structure refinement are 0.86 and 1.46% m/m, respectively. Trace element mass fractions measured via LA‐ICP‐MS in two laboratories are in good agreement, and spots from five fragments for both Kakanui and Arenal amphiboles are generally consistent within reproducibility precision (2s). Our measurements indicate a better homogeneity for the amphiboles from Kakanui than that from Arenal. According to the latest scheme for amphibole classification and nomenclature (Hawthorne et al. 2012), the sample from Arenal is a (partially dehydrogenated) pargasite, and that from Kakanui is a kaersutite. The significant amount of oxo‐component and that CTi4+ content is strongly ordered at the M(1) site for both amphiboles indicate crystallisation under high fO2 conditions. [ABSTRACT FROM AUTHOR]

Pre-stack seismic inversion based on sensitive elastic parameters is critical in reservoir lithology prediction and geofluid identification. The ability of a single elastic attribute to identify a reservoir depends on its sufficient sensitivity to distinguish the target reservoir from the surrounding sediments. In general, high-dimensional data space composed of multiple elastic attributes is more conducive to describing reservoir characteristics. Therefore, a multiple elastic attribute fusion method using affinity propagation clustering strategy for gas hydrate reservoir identification is proposed. Rock-physics modeling is the most effective tool to determine the influence of microscopic physical parameters on macroscopic elastic response and to quantitatively evaluate the sensitivity of elastic attributes. Consequently, a rock-physics model of hydrate sediments considering the non-negligible shear properties of hydrates is constructed to clarify reservoir-sensitive elastic parameters. Additionally, a clustering evaluation indicator is defined to determine the optimal data clustering dimension in terms of feasibility and economy of the proposed method, and to avoid bias in the results due to data redundancy. It is shown that the 3D elastic attribute space consisting of shear modulus, Young's modulus, and S-wave velocity has the best discrimination ability for hydrate reservoirs. The logging data are used to verify the feasibility and effectiveness of the proposed method. Finally, the hydrate reservoir development is accurately discriminated by using the multiple elastic attributes yield from the pre-stack seismic inversion and combined with the fusion strategy. [ABSTRACT FROM AUTHOR]

• A novel approach for energy- and catalyst-free activation of peracetic acid (PAA). • Bioelectrochemical activation of PAA yielded •OH at a 3:1 ratio to CH 3 C(O)O•. • •OH, CH 3 C(O)O• reacting with PAA to form CH 3 C(O)OO• contributes 68.1 % SMX removal. • The transformation byproducts of SMX and their toxicities were assessed. • The new activation method validated with 21 typical pharmaceuticals at neutral pH. Peracetic acid (PAA) has received increasing attention as an alternative oxidant for wastewater treatment. However, existing processes for PAA activation to generate reactive species typically require external energy input (e.g., electrically and UV-mediated activation) or catalysts (e.g., Co2+), inevitably increasing treatment costs or introducing potential new contaminants that necessitate additional removal. In this work, we developed a catalyst-free, self-sustaining bioelectrochemical approach within a two-chamber bioelectrochemical system (BES), where a cathode electrode in-situ activates PAA using renewable biogenic electrons generated by anodic exoelectrogens (e.g., Geobacter) degrading biodegradable organic matter (e.g., acetic acid) in wastewater at the anode. This innovative BES-PAA technique achieved 98 % and 81 % removal of 2 µM sulfamethoxazole (SMX) in two hours at pH 2 (cation exchange membrane) and pH 6 (bipolar membrane) using 100 μM PAA without external voltage. Mechanistic studies, including radical quenching, molecular probe validation, electron spin resonance (ESR) experiments, and density functional theory (DFT) calculations, revealed that SMX degradation was driven by reactive species generated via biogenic electron-mediated O O cleavage of PAA, with CH 3 C(O)OO• contributing 68.1 %, •OH of 18.4 %, and CH 3 C(O)O• of 9.4 %, where initial formation of •OH and CH 3 C(O)O• rapidly reacts with PAA to produce CH 3 C(O)OO•. The presence of common water constituents such as anions (e.g., Cl−, NO 3 −, and H 2 PO 4 −) and humic acid (HA) significantly hinders SMX removal via the BES-PAA technique, whereas CO 3 2− and HCO 3 − ions have a comparatively minor impact. Additionally, the study investigated the removal of various pharmaceuticals present in secondary treated municipal wastewater, attributing differences in removal efficiency to the selective action of CH 3 C(O)OO•. This research demonstrates a novel PAA activation method that is ecologically benign, inexpensive, and capable of overcoming catalyst deactivation and secondary pollution issues. [Display omitted] [ABSTRACT FROM AUTHOR]

Research on microwave absorbing (MA) metamaterials with multifunctional coupling designs is a burgeoning topic. Reported here is a design paradigm for architecting mechanically robust all-dielectric MA metamaterials reaching perfect electromagnetic wave absorption. First, we generalized rules of optimal permittivities for nonmagnetic materials reaching theoretically ultimate reflection loss (RL) smaller than −150 dB, and proposed a facile criterion for evaluating MA performance based on the offset of dielectric Cole-Cole curves from theoretical optimal values. Subsequently, electromagnetic tunable polymer-derived SiOC ceramics with the highest reported printing accuracy of 20 μm were developed as metamaterials matrix, and the strong-lightweight gyroid shell-cellular (shellular) is introduced to optimize the MA performance while balancing mechanical properties. Finally, as-fabricated gyroid shellular MA metamaterials exhibit an unmatched MA performance coupled with unparalleled mechanical properties: the minimum RL achieves the ceiling value of −70.3 dB, the effective absorption bandwidth spans the whole X-band, and the specific compressive strength is as high as 63.0 MPa/(g/cm3) at 0.606 g/cm3 ultralow density. Besides, the theoretical framework was well-established for guiding structural optimization and practical manufacturing of inhomogeneous metamaterials. This research advanced an unambiguous theoretical direction for the development of structure-function integrated MA metamaterials through the synergistic interaction among theory, computation, and experiment. [Display omitted] • Optimal permittivity yielding ultimate reflection loss (≤−150 dB) was uncovered. • A Photocurable SiOC-based slurry was developed with 20 μm printing accuracy. • A modified Maxwell-Garnett effective medium theory is introduced. • The theoretical basis for designing metamaterials absorbers was well-established. [ABSTRACT FROM AUTHOR]

Background: Zika virus (ZIKV) and dengue virus (DENV) are closely related flaviviruses primarily transmitted by Aedes mosquitoes. Armigeres subalbatus is an emerging and widely distributed mosquito, and ZIKV has been detected and isolated from it. However, it is not clear whether Ar. subalbatus could be a vector for ZIKV and DENV or not. In this study, we investigated the infection and transmission of Ar. subalbatus to ZIKV and DENV. Methods: A line of Ar. subalbatus was isolated from Guangdong, China, and further identified by the mitochondrial cytochrome oxidase subunit 1 (COI) gene. The adults of Ar. subalbatus were fed with blood meal containing ZIKV or DENV-2. At 4, 7, 10, 14, and 21 days post-inoculation (dpi), the infections of ZIKV or DENV-2 in the midguts, ovaries and salivary glands were detected and quantified by RT-PCR and RT-qPCR. To assess the transmissibility, suckling mice were exposed to bites of ZIKV-infected mosquitoes, and ZIKV was detected in brain tissue by RT-qPCR and plaque assays. Furthermore, the larvae of Ar. subalbatus were reared in artificial urine containing ZIKV or DENV-2. The infection rates and viral titers of larvae and adults were analyzed by RT-PCR and RT-qPCR, and the viral distribution in larval tissues was observed by immunohistochemistry. Chi-square test and one-way ANOVA analysis were used for assessing the infection rate and viral titer in varied tissues and different time points, respectively. Results: Following oral inoculation, ZIKV but not DENV-2 could be detected in Ar. subalbatus midguts at 4 dpi, ovaries at 7 dpi and salivary glands at 10 dpi. The highest infection rate (IR) of ZIKV was 27.8% in midgut at 7 dpi, 9.7% in ovary and 5.6% in salivary gland at 21 dpi. Eight days after being bitten by ZIKV-positive mosquitoes, ZIKV was detected in three brain tissues out of four suckling mice exposed to bites. ZIKV could be detected in the larvae reared in artificial urine contained ZIKV at a high concentration of 105 pfu/ml and various tissues of adults with a low infection rate (0.70–1.35%). ZIKV could be observed in anal papillae and midgut of larvae at 4 dpi under laboratory conditions. Conclusions: ZIKV but not DENV-2 can infect Ar. subalbatus by blood meal and artificial urine, and the infected mosquitoes can transmit ZIKV to suckling mice by bite. From these findings, we can conclude that the Ar. subalbatus isolated from Guangdong province, China, is a potential vector for ZIKV and should therefore be considered in vector control programs to prevent and control of Zika virus disease. [ABSTRACT FROM AUTHOR]

• Twin SiC nanowires were successfully fabricated in 3D printed SiOC ceramic. • The ceramic exhibited high permittivity in X-band, which is beneficial for the electromagnetic shielding effectiveness. • The ceramic possess good mechanical property, which indicates its potential in practical application. Effective electromagnetic interference (EMI) shielding requires materials with high permittivity. The current study reports 3D printed polymer-derived SiOC ceramics (PDC) modified with SiC nanowires (SiC nw) exhibiting both high real and imaginary parts of permittivity within X-band. SEM results indicated that a large number of pores and cracks exist in the SiOC, and twinned SiC nw were uniformly grown among them along with the existence of graphite microcrystals when the sintering temperature was 1500 ℃. The real part of permittivity ranged from 16.6 to 28.9 while the imaginary part from 31.7 to 34.2 in X-band. The EMI total shielding effectiveness (SE T) of the ceramics could reach 34.7 dB with absorption loss (SE A) of 29.3 dB and reflection loss (SE R) of 5.4 dB. Meanwhile, the 3D printed PDC-SiOC ceramics at 900 ℃ sintering temperature possess certain mechanical properties with the magnitude of compressive strength being 12.57 MPa. [ABSTRACT FROM AUTHOR]

• Self-powered, chemical-catalyst-free way to activate PI for micropollutant removal. • Renewable biogenic mediated direct or indirect activation of PI at different pH. • PI undergoes direct single electron transfer to form •IO 3 under acidic conditions. • Carbon cathode tunes 2e− reaction, forms H 2 O 2 to activate PI, yields •OH neutrally. • Ti mesh cathode tunes 4e− reduction, forms OH− to activate PI, yields •O 2 − and 1O 2. The periodate (PI)-based advanced oxidation process is valued for environmental remediation, but current activation methods involve high costs, secondary contamination risks, and limited applicability due to external energy inputs (e.g., UV), catalyst incorporation (e.g., Fe2+), or environmental modifications (e.g., freezing). In this work, novel bioelectric activation of PI using the electrons generated by electroactive bacteria was developed and investigated for rapid removal of carbamazepine (CBZ), achieving 100 %, 100 %, and 76 % removal efficiency for 4.22 µM of CBZ in 20 min at pH 2, 120 min at pH 6.4, and HRT of 30 min at pH 8.5, respectively, with a 1 mM PI dose and without an input voltage. It was deduced that electrons derived from bacteria could directly activate PI using Ti mesh electrodes and generate •IO 3 via single electron transfer under strongly acidic conditions (e.g., pH 2). Nevertheless, under weak alkaline conditions (e.g., pH 8.5), biogenic electrons indirectly activated PI by generating OH−via 4e−reduction at the Ti mesh cathode, resulting in the formation of •O 2 − and 1O 2. In addition to the metal cathode, a carbon-based cathode finely modulates the 2e−reduction, yielding H 2 O 2 and activating PI to mainly form •OH. Moreover, primarily non-toxic IO 3 − was produced during treatment, while no detectable reactive iodine species (HOI, I 2 , and I 3 −) were observed. Furthermore, the bioelectric activation of PI demonstrated its capability to remove various micropollutants present in secondary-treated municipal wastewater, showcasing its broad-spectrum degradation ability. This study introduces a novel, cost-effective, and environmentally friendly PI activation technique with promising applicability for micropollutant elimination in water treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper studies the fixed-time synchronization (FDTS) of complex-valued neural networks (CVNNs) based on quantized intermittent control (QIC) and applies it to image protection and 3D point cloud information protection. A new controller was designed which achieved FDTS of the CVNNs, with the estimation of the convergence time not dependent on the initial state. Our approach divides the neural network into two real-valued systems and then combines the framework of the Lyapunov method to give criteria for FDTS. Applying synchronization to image protection, the image will be encrypted with a drive system sequence and decrypted with a response system sequence. The quality of image encryption and decryption depends on the synchronization error. Meanwhile, the depth image of the object is encrypted and then the 3D point cloud is reconstructed based on the decrypted depth image. This means that the 3D point cloud information is protected. Finally, simulation examples verify the efficacy of the controller and the synchronization criterion, giving results for applications in image protection and 3D point cloud information protection. [ABSTRACT FROM AUTHOR]

• Microkinetic models of HDO of propanoic acid over Rh(1 1 1) in gas and liquid phases. • Lateral interactions between surface species and transition states considered. • Rh(1 1 1) not active site for decarboxylation and decarbonylation reactions. • Rh(1 1 1) active site for propanol and propionaldehyde production in all environments. • Liquid water and 1,4-dioxane increase HDO rate but hardly affect selectivity. Microkinetic models based on first principles calculations have been used to study the vapor and liquid phase hydrodeoxygenation of propionic acid on a Rh(1 1 1) surface. Calculations suggest that both decarboxylation and decarbonylation do not occur at an appreciable rate under all reaction environments. Propanol and propionaldehyde are the main products on this surface and they are produced at similar rates in both vapor and liquid phase environments. While a condensed phase can shift the reaction rate, the dominant pathways and selectivity towards the various products are hardly affected. At 473 K, the turnover frequency is increased by about a factor of 1.5 in liquid water relative to the gas phase. In liquid 1,4-dioxane, the turnover frequency is also slightly increased relative to the gas phase. Given the uncertainty in Rh cavity radius in the liquid phase calculations, computations with different cavity radii have been performed. With larger Rh cavity radius, the promotional effect of the solvents on the turnover frequency becomes more significant, while practically no changes are observed for a smaller cavity radius. [ABSTRACT FROM AUTHOR]

• Microkinetic models of HDO of propanoic acid over Pt (1 1 1) in gas and liquid phases. • Lateral interactions of dominant surface species are considered in all models. • Decarboxylation does not occur at an appreciable rate. • In vapor phase, decarbonylation products, propanol and propanal are all produced. • In liquid phase, reaction selectivity shifts towards propanol and propanal. Microkinetic models based on first principles calculations have been developed for the vapor and liquid phase hydrodeoxygenation of propionic acid over a Pt (1 1 1) surface. Calculations suggest that decarboxylation does not occur at an appreciable rate. In the vapor phase, decarbonylation products, propanal and propanol are all produced at similar rates. However, in both liquid water and 1,4-dioxane, propanol and propanal are favored over decarbonylation products. While a condensed phase can shift the reaction rate and selectivity significantly, the dominant pathways towards the various products are hardly affected. Only for propanal production do we observe a shift in mechanism. At 473 K, the propionic acid conversion rate is increased by one order of magnitude in liquid 1,4-dioxane relative to the gas phase. In liquid water, the conversion rate is similar to the vapor phase since adsorbed propionic acid blocks a large fraction of the surface sites. [ABSTRACT FROM AUTHOR]

Nano‐single‐atom‐catalysts have the potential to combine the respective advantages of both nano‐catalysts and single‐atom‐catalysts and thus exhibit enhanced performance. Generally, the separation of active sites in space limits the interaction between single atoms and nanoparticles. Heterointerface engineering has the potential to break this limitation. Regretfully, studies on the interface effect between single atoms and nanoparticles are rarely reported. Herein, an unprecedented nano‐single‐atom heterointerface composed of Fe single‐atoms and carbon‐shell‐coated FeP nanoparticles (Fe SAC/FeP@C) is demonstrated as an efficient electrocatalyst for the nitrate reduction process from alkaline to acidic. Compared with typical nano‐single‐atom‐catalysts (Fe SAC/FePO4) and single‐atom‐catalysts (Fe SAC), the constructed Fe SAC/FeP@C heterostructure exhibits dramatically enhanced nitrate‐to‐ammonia performance. Especially in acidic media, the maxmium Faradaic efficiency of ammonia (NH3) can reach 95.6 ± 0.5%, with a maximum NH3 yield of 36.2 ± 3.1 mg h−1 mgcat−1 (pH = 1.2), which is considerably higher than previously reported. Density functional theory calculations and in situ spectroscopic investigations indicate that the unique charge redistribution at the interface, together with the optimized electronic structure of Fe single‐atoms, strengthens intermediate adsorption and catalytic activity. This work provides a feasible strategy for designing nano‐single‐atom‐catalysts with unique heterointerfaces, as well as valuable insights into nitrate conversion under environmentally relevant wastewater conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • I− substantially increased the abatement of bisphenol A (BPA) by PAA. • •I produced from the single electron transfer pathway dominated the I−/PAA process. • Cl− and Br− at high doses aided PAA in removing BPA by forming HOCl and HOBr. • Operational parameters and water matrices can affect the oxidation process. • The I−/PAA technique removes micropollutants with a high degree of selectivity. In recent years, halogen radical-based advanced oxidation processes (AOPs) have shown promise for metal-free, highly selective elimination of phenolic pollutants with high mineralization. This study explored a novel approach combing peracetic acid (PAA) and naturally available I− to efficiently remove bisphenol A (BPA) over a broad pH range (2–8). A dose of 500 μM PAA and 100 μM I− at a pH of 3 completely eliminated 43.8 µM of BPA within 10 min. Aside from I−, two more halogen ions, Cl− and Br−, could also enhance BPA elimination in the presence of PAA. Based on quenching experiments and density functional theory (DFT) thermodynamic calculations, only I− among the three halogen ions can react with PAA (primarily through the single electron transfer pathway) to generate •I, which efficiently removes BPA. The Cl− and Br− only contribute partially to the BPA removal, mainly through HOCl and HOBr following the oxygen atom transfer pathway. The water matrices had no noticeable influence on the I−/PAA process, and eliminating micropollutants with electron-rich groups from actual water samples remained effective. This work proposes an innovative and feasible technique for PAA-based AOPs and showcases its promising applicability for the treatment of phenolic contaminants in wastewater. [ABSTRACT FROM AUTHOR]

A copper‐catalysed double O‐aylation for enantioselective formation of chiral oxa‐spirocycles is described. The method is based on a stepwise process and afforded chiral oxa‐spirocycles with good yields and moderate to high enantioselectivities. [ABSTRACT FROM AUTHOR]

The optimization of multi-objective dynamic economic-grid fluctuation dispatch (MODEGD) involves simultaneous optimization of two competing objectives, fuel cost and grid fluctuation, while fulfilling constraints. In this paper, an improved version of the multi-objective marine predator algorithm (IMOMPA), is proposed for solving MODEGD considering plug-in electric vehicles. The IMOMPA algorithm improves upon the existing multi-objective marine predator algorithm in three key ways. Firstly, the initial population's diversity is enhanced using opposition learning combined with chaotic mapping. Secondly, a nonlinear convergence factor is introduced to speed up the convergence. Finally, the spiral search mechanism from the whale optimization algorithm (WOA) is incorporated to improve the algorithm's global search ability. By testing the performance of IMOMPA on ZDT series and DTLZ series multi-objective benchmark functions, IMOMPA shows strong local search capability, better robustness, and better convergence speed and convergence accuracy. Moreover, connecting plug-in electric vehicles (PEVs) to the grid (V2G), can mitigate grid fluctuations and balance peak demand periods. To validate the feasibility of the proposed IMOMPA, numerical experiments are performed on multi-objective benchmark functions and generation units of varying scales. The results demonstrate the superiority of the IMOMPA algorithm compared to other alternatives. • The improved multi-objective marine predator algorithm has stronger local search capability and higher solution accuracy. • Multi-objective dynamic economic dispatch is a new model that considers grid fluctuation. • A series of non-dominated solutions are gained instead of a single solution. • The diversity of solutions is essentially improved. [ABSTRACT FROM AUTHOR]

To reduce the cost of the thermal diodes and increase its unidirectional heat transfer reliability, a thermal diode with tesla valve structure is proposed and its thermal performance is experimentally investigated. The relation between the structure parameters (including branch angle α , channel depth d , number of unit n and number of channel N) and the fluid flow performance of tesla vapor channel is studied by numerical simulation. According to the simulation results, the parameters of α = 30°, d = 1.5 mm, n = 16 and N = 4 were chosen for the vapor channel in thermal diode. Experimental results show that the reverse thermal resistance is larger than the forward thermal resistance under the wide range of working conditions, indicating the good unidirectional heat transport capacity of the proposed thermal diode. The maximum ratio of reverse thermal resistance to forward thermal resistance K reaches around 3.02 under the filling ratio of 24% and the heating power of 7 W. [ABSTRACT FROM AUTHOR]

Rock-physics modeling of hydrate reservoirs is an efficacious solution for assessing the macroscopic elastic responses of rocks induced by microphysical parameters, pore structure, and fluid properties. Although many applicable rock-physics models have been proposed successively for different research objectives, several issues still need attention. Firstly, the previous studies have mainly focused on the effects of hydrate distribution morphology and pore structure, ignoring the mixing characteristics of different components in the pore fluid. Secondly, since the elastic modulus of hydrates differs greatly from that of conventional fluids, the reasonable setting of its elastic parameters will significantly affect the estimation results of the model. Additionally, too many parameters describing the pore structure will bring great uncertainty to the calculation results, while how to further consider the unconsolidated characteristics of the hydrate sediments in the modeling needs to be further investigated. To address the above problems, CT images of cores were used to elucidate the mixing relationship of hydrate, water, and gas, and the calculation of the equivalent fluid elastic modulus was proposed. The temperature dependence of the hydrate elastic modulus is obtained from experimental data and the elastic parameters are assigned by temperature in the modeling process. On this basis, the descriptive parameters of the pore structure are simplified by using the equivalent shape factor, and the unconsolidated characteristic of the sediments is described by introducing the consolidation parameter. In this study, we proposed a new modeling process for hydrate reservoirs and elaborated the rationality and necessity of the modeling idea in the numerical analysis, which finally achieved satisfactory results in the field data collected at the South China Sea. • The equivalent fluid elastic modulus calculation method based on core analysis data was developed; • Simplifying the process of calculating the elastic modulus of the dry frame; • Based on experimental data, the temperature dependence of hydrate elastic modulus was obtained. [ABSTRACT FROM AUTHOR]

The highest power conversion efficiencies (PCEs) reported for perovskite solar cells (PSCs) with inverted planar structures are still inferior to those of PSCs with regular structures, mainly because of lower open-circuit voltages ( V oc ). Here we report a strategy to reduce nonradiative recombination for the inverted devices, based on a simple solution-processed secondary growth technique. This approach produces a wider bandgap top layer and a more n-type perovskite film, which mitigates nonradiative recombination, leading to an increase in V oc by up to 100 millivolts. We achieved a high V oc of 1.21 volts without sacrificing photocurrent, corresponding to a voltage deficit of 0.41 volts at a bandgap of 1.62 electron volts. This improvement led to a stabilized power output approaching 21% at the maximum power point. [ABSTRACT FROM AUTHOR]

Abstract: Organic–inorganic hybrid perovskite photodetectors have been reported to possess superior optoelectronic properties, such as high sensitivity, ultrafast response, and capability of strongly absorbing the light in the visible range. While in the near‐infrared range, the performances of these photodetectors deteriorate seriously, originating from the weak coupling of infrared light to the perovskites. In this study, an organic–inorganic hybrid perovskite photodetector on arrays of Au nanostructures is fabricated, which exhibits a remarkable photocurrent enhancement in the visible and near‐infrared range, ascribed to the huge localized electric field induced by the surface plasmon resonance of Au nanostructures. The maximum external quantum efficiency of this photodetector is as high as about 65%, 2.5 times that on a usual Si/SiO2 substrate without Au nanostructures. Obviously, by exploiting Au nanostructures, the light harvesting ability of the photodetector breaks through the perovskite absorption edge, and extends to the near‐infrared range. [ABSTRACT FROM AUTHOR]

Conventional experientialism-inspired and intuition-inspired research on microwave-absorbing (MA) materials appears to lack efficiency. The present work aims to establish a scalable parametrization-design methodology for multifunctional coupled MA metamaterials involving up-front theoretical calculation and simulation predictions followed by experimental verification. A top-down parametrization-design methodology is proposed herein, which relies on the utilization of polymer-derived ceramics (PDCs) with flexible electromagnetic tunability as substrate materials, combined with tunable electromagnetic response via mathematical modeling of triply-periodic-minimal-surfaces shellular structures. In the process, preferred structural configuration and orientation are screened with actual requirements while final fabrication in a single step is enabled by 3D printing technology. The effect of structural configuration and orientation on electromagnetic response is scrutinized and a novel optimization method for deterministic high-temperature MA properties is proposed. As-fabricated [111]-oriented Gyroid shellular MA metamaterials exhibit superior overall performance in the X-Ku band with wide-temperature adaptability. At room temperature, the minimal reflection loss (RL min) value is –58.05 dB, effective absorbing bandwidth (EAB) with RL ≤ –10 dB reaches 6.11 GHz, and the specific strength reaches 65.20 MPa/(g/cm3) at the ultralow density of 0.550 g/cm3. RL min improves to –72.38 dB at 100 °C while EAB increases to 6.77 GHz at 300 °C and retains 5.60 GHz at 600 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-Ru@ Ru-PSFM nanostructured cathode is constructed via the in-situ exsolution technique. • Electrolysis current density at 2.0 V is greatly improved from 0.707 to 1.480 Acm−2 after Ru doping. • R p at 1.4 V is significantly decreased from 2.228 to 0.319 Ωcm−2 by Ru promotion. • CO 2 RR performance enhancement mechanism is explained by DFT calculation. • CO 2 RR rate is determined by CO 2 adsorption, dissociation, and activation process. Electrochemical carbon dioxide reduction reaction (CO 2 RR) via a solid oxide CO 2 electrolyzer has been attracting increasing attention because it can effectively convert CO 2 into high value-added chemical products and efficiently store the excessive electricity. However, the lack of efficient electrodes to catalyze this reaction process severely limits their practical applications. Herein, we report Ru promoted perovskite type Pr 0.4 Sr 0.6 Fe 0.9 Mo 0.1 O 3-δ with a general formula of Pr 0.4 Sr 0.6 Fe 0.8 Ru 0.1 Mo 0.1 O 3-δ (Ru-PSFM) cathode to overcome the constraints of low current density, low Faradaic efficiency, and high overpotential of CO 2 RR. The cathode electrolysis current density of CO 2 RR at 800 °C and 2.0 V is considerably improved from 0.707 to 1.480 A cm−2 with an enhancement rate of 109%, while its corresponding electrode polarization resistance at 1.4 V is significantly lowered from 2.228 to 0.319 Ω cm−2. Furthermore, the solid oxide CO 2 electrolyzer exhibits superior stability during the operation. Distribution of relaxation times analysis results reveal that the rate-determining process, involving CO 2 adsorption, dissociation, and activation on the cathode surface, is significantly activated and dramatically accelerated after Ru doping. Density function theory calculations demonstrate that the in-situ exsolved Fe-Ru alloy nanocatalyst is a more favorable site for the activation of CO 2 dissociation. This work provides valuable insights into the rational design of efficient cathodes for CO 2 RR. [ABSTRACT FROM AUTHOR]

The Nan-Uttaradit suture is marked by a narrow N-S trending and discontinuous ophiolite belt in northern Thailand. This suture zone is a mélange composed of gabbro, tholeiitic metabasalt, andesite and radiolarian chert. Samples of gabbro and meta-basalt in the Nan-Uttaradit suture yield zircon U-Pb ages of 311±10 and 316±3 Ma, respectively, interpreted as the crystallization ages of the rocks, suggesting the Nan-Uttaradit Ocean existed in the Late Carboniferous. Our results indicate that the Nan-Uttaradit Ocean co-existed with the Ailaoshan-Jinshajiang Ocean to the north and was probably an along-strike extension of the latter. [ABSTRACT FROM AUTHOR]

Polyacrylate/graphene oxide (GO) nanocomposites were prepared by the copolymerisation of GO with acrylic acid and acrylamide. The effects of polyacrylate/GO nanocomposites on cement paste fluidity and the microstructure and mechanical strength of hardened cement paste were investigated. The results indicate that the GO nanocomposites have no effect on cement paste fluidity and can efficiently control cement hydration products and its microstructure compared with using GO sheets directly. The corresponding hardened cement paste has a high compressive strength and particularly high flexural strength. This research provides a basis for the use of GO in cement-based composites for reinforcing and toughening. [ABSTRACT FROM AUTHOR]

O-Heterocyclic structures such as 2,3-dihydrobenzofurans are key motifs in many natural compounds and pharmaceuticals. Enantioselective formation of chiral dihydrobenzofurans and analogues was achieved through a copper-catalyzed desymmetrization strategy with a chiral cyclic 1,2-diamine. A broad range of substrates are compatible with this CuI-diamine catalytic system and afford the desired coupling products with chiral tertiary or quaternary carbon centers in high yields and good to excellent enantioselectivities under mild conditions. [ABSTRACT FROM AUTHOR]

O-Heterocyclic structures such as 2,3-dihydrobenzofurans are key motifs in many natural compounds and pharmaceuticals. Enantioselective formation of chiral dihydrobenzofurans and analogues was achieved through a copper-catalyzed desymmetrization strategy with a chiral cyclic 1,2-diamine. A broad range of substrates are compatible with this CuI-diamine catalytic system and afford the desired coupling products with chiral tertiary or quaternary carbon centers in high yields and good to excellent enantioselectivities under mild conditions. [ABSTRACT FROM AUTHOR]

Chlamydomonas reinhardtii is a unicellular, soil-dwelling (and aquatic) green alga that has significant metabolic flexibility for balancing redox equivalents and generating ATP when it experiences hypoxic/anoxic conditions. The diversity of pathways available to ferment sugars is often revealed in mutants in which the activities of specific branches of fermentative metabolism have been eliminated; compensatory pathways that have little activity in parental strains under standard laboratory fermentative conditions are often activated. The ways in which these pathways are regulated and integrated have not been extensively explored. In this review, we primarily discuss the intricacies of dark anoxic metabolism in Chlamydomonas, but also discuss aspects of dark oxic metabolism, the utilization of acetate, and the relatively uncharacterized but critical interactions that link chloroplastic and mitochondrial metabolic networks. [ABSTRACT FROM AUTHOR]

Chlamydomonas reinhardtii insertion mutants disrupted for genes encoding acetate kinases (EC 2.7.2.1) (ACK1 and ACK2) and a phosphate acetyltransferase (EC 2.3.1.8) (PAT2, but not PAT1) were isolated to characterize fermentative acetate production. ACK1 and PAT2 were localized to chloroplasts, while ACK2 and PAT1 were shown to be in mitochondria. Characterization of the mutants showed that PAT2 and ACK1 activity in chloroplasts plays a dominant role (relative to ACK2 and PAT1 in mitochondria) in producing acetate under dark, anoxic conditions and, surprisingly, also suggested that Chlamydomonas has other pathways that generate acetate in the absence of ACK activity. We identified a number of proteins associated with alternative pathways for acetate production that are encoded on the Chlamydomonas genome. Furthermore, we observed that only modest alterations in the accumulation of fermentative products occurred in the ack1 , ack2 , and ack1 ack2 mutants, which contrasts with the substantial metabolite alterations described in strains devoid of other key fermentation enzymes. [ABSTRACT FROM AUTHOR]

• Focusing on 3D printed metamaterial absorbers. • Latest progress on fabrication and design of metamaterial absorbers is reviewed. • The future research trends are pointed out. Recent utilization of metamaterial design idea, which presents unique and designable electromagnetic properties, has been prompting the establishment of new stage of electromagnetic metamaterial absorber (EMMA) researches as well as enabling the possibility of the integration of structure and function. Great advances have been made since the first metamaterial perfect absorber (MPA) demonstrated in 2008. In addition to MPAs, broadband EMMAs, polarization independent and angle insensitive EMMAs and tunable EMMAs have been proposed to enlarge the application range of metamaterials in various situations. With an increasing demand for EMMAs operating at modern complex electromagnetic environment, the trend of high integration of full-band, wide-angle and active frequency tunable is inevitable in the future. From this perspective, a progress report should be given to summarize the progress in stages and to inspire researchers for their future studies. The emphasis of this report is given on the structural designs, absorbing performances, fabrication methods and the mechanisms of EMMA. Outlook and insight on the defect of current studies and future developing trend are also provided. [ABSTRACT FROM AUTHOR]

For the first time, copper-catalyzed intramolecular N-arylation was successfully applied to the kinetic resolution strategy. Under the catalysis of CuI–BINOL derived ligands, the kinetic resolution of rac-2-amino-3-(2-iodoaryl)propionates and rac-2-amino-4-(2-iodoaryl)butanoates afforded chiral intramolecular coupling products and recovered the starting materials in high enantioselectivity (sfactors up to 245). [ABSTRACT FROM AUTHOR]

This paper considers the fixed-time synchronization (FIXTS) of neural networks (NNs) by using quantized intermittent control (QIC). Based on QIC, a fixed-time controller is designed to ensure that the NNs achieve synchronization in finite time. With this controller, the settling time can be estimated regardless of initial conditions. After ensuring that the system has stabilized through this strategy, it is suitable for image protection given the behavior of the system. Meanwhile, the encryption effect of the image depends on the encryption algorithm, and the quality of the decrypted image depends on the synchronization error of NNs. The numerical results show that the designed controller is effective and validate the practical application of FIXTS of NNs in image protection. [ABSTRACT FROM AUTHOR]

Abstract: Simulated annealing (SA) and genetic algorithm (GA) are utilized to optimize Interpolation Markov Chains (IMC) model for promoter recognition. The deletions and insertions of nucleotides in DNA sequences are introduced into the IMC model whose transition probabilities are established with SA. The noise is filtered to reduce the complexity of model parameters. And to improve the gradient descent algorithm being liable to fall into the local minimum point, GA is presented for an automated estimation of global optimal interpolation coefficients. A simulation result shows that the sensitivity and specificity in promoter level are both higher than 86% on the test set. [Copyright &y& Elsevier]

High-quality Sr isotope data are critically dependent on the quality of reference materials that are used for instrumental calibration and data monitoring during laser ablation (LA) multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) analysis. We have prepared a new natural calcite reference material MNP for in situ Sr isotope measurement by LA-MC-ICP-MS. Detailed textural examination and major element determination suggest that the MNP calcite reference material has no growth rim or zoning. Trace element analyses by LA-ICP-MS showed that the MNP calcite reference material has low Rb/Sr ratios, low amounts of heavy rare earth elements (HREEs) and high Sr contents. The MNP calcite reference material is homogeneous with respect to Sr isotopes based on a large number of measurements performed by single-grain solution nebulizer (SN)-MC-ICP-MS and LA-MC-ICP-MS. The traditional bulk isotope analyses by TIMS and SN-MC-ICP-MS yielded a mean 87Sr/86Sr ratio of 0.70617 ± 0.00005(2SD, n = 18). A total of 585 LA-MC-ICP-MS Sr isotope analyses on random calcite crystals show homogeneous Sr isotopic compositions with an average 87Sr/86Sr ratio of 0.70617 ± 0.00005 (2SD), identical with the solution-based data. These suggest that MNP calcite can be used as a potential reference material for microbeam Sr isotopic analysis. [ABSTRACT FROM AUTHOR]

The infrared image diagnostic technology of substation equipment is often interfered by its complex background, and cannot reflect the effective temperature information of the equipment, which is not conducive to the realization of subsequent fault diagnosis. In order to solve this problem, an improved CenterNet is proposed to improve the recognition effect of substation equipment under complex backgrounds. First, a richer substation infrared image dataset is established. Second, the Iresgroup structure is proposed as a backbone to further improve the feature learning ability of CenterNet. In the Iresgroup structure, an improved projection shortcut and Iresnet structure are improved to control the number of ReLUs on the main path, which can further improve the detection accuracy of the model, with higher robustness. In addition, the group conv structure is used to further improve the model, so that the model maintains the same amount of parameters while strengthening its feature learning ability. At last, The hyperparameters of centerNet have been redesigned to further improve the accuracy of the proposed method. The results show that compared with the several native backbones of the CenterNet and several mainstream detection models, this method has a significant improvement of 2% to 4% on mAP, and the improvement of single-type objects is as high as 7.4%. It can be seen that this method has achieved excellent detection results and can provide key technical support for fault detection of substation equipment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eh-pH diagram of K-S-Fe-H 2 O system is established to analyze the iron removal. • Controlling high potential and a certain pH value are good for jarosite process. • Efficient and selective iron removal from acid solution has been achieved. • Regular ellipsoidal particles of jarosite with even particle size are obtained. • The crystallization mechanism and kinetics of jarosite formation are analyzed. Aerospace magnetic material scraps are abundant in cobalt and nickel. Sulfuric acid leaching process is an efficient method for extracting them. But it is a non-selective process, a significant amount of iron dissolves in the solution. This study focuses on the selective removal of iron from this solution using the jarosite process. E h -pH diagram of K-S-Fe-H 2 O system was established. Based on thermodynamic analysis, H 2 O 2 is used to oxidize Fe2+ into Fe3+, achieving efficient and selective removal of iron from the solution containing cobalt and nickel. The optimal conditions are as follows: temperature 95°C, K 2 SO 4 dosage coefficient 1.5, seed dosage 10 g/L, time 90 min, pH 1.76, and endpoint pH controlled at approximately 3. Under these conditions, the iron removal efficiency is above 99%, while the loss ratios of cobalt and nickel are below 2%. The product is characterized by XRD and SEM-EDS. Results indicate that the product is jarosite ((K,H 3 O)Fe 3 (SO 4) 2 (OH) 6), exhibiting an ellipsoid structure with the mean particle size in the range of 0.2–5.0 μm. Temperature, pH value and seed dosage significantly affect reaction rate, particle size and crystallinity, and K 2 SO 4 dosage mainly affects reaction rate and the morphology of jarosite. The jarosite crystallization kinetics can be described by the Avrami equation, with an Avrami index (n) of approximately 2.5 and the apparent activation energy of 42.68 kJ/mol. [ABSTRACT FROM AUTHOR]

Thousands of nuclear-encoded proteins are transported into chloroplasts through the TOC–TIC translocon that spans the chloroplast envelope membranes. A motor complex pulls the translocated proteins out of the TOC–TIC complex into the chloroplast stroma by hydrolyzing ATP. The Orf2971–FtsHi complex has been suggested to serve as the ATP-hydrolyzing motor in Chlamydomonas reinhardtii , but little is known about its architecture and assembly. Here, we report the 3.2-Å resolution structure of the Chlamydomonas Orf2971–FtsHi complex. The 20-subunit complex spans the chloroplast inner envelope, with two bulky modules protruding into the intermembrane space and stromal matrix. Six subunits form a hetero-hexamer that potentially provides the pulling force through ATP hydrolysis. The remaining subunits, including potential enzymes/chaperones, likely facilitate the complex assembly and regulate its proper function. Taken together, our results provide the structural foundation for a mechanistic understanding of chloroplast protein translocation. The Orf2971–FtsHi complex in Chlamydomonas reinhardtii functions as an ATP-hydrolyzing motor for pulling proteins from the chloroplast translocon. Its 3.2-Å resolution structure reveals a 20-subunit complex spanning the chloroplast inner envelope with large modules in the intermembrane space and stromal matrix. Results suggest that the hetero-hexameric core generates pulling force and that other subunits assist in complex assembly and regulation, offering new insights into chloroplast protein translocation. [ABSTRACT FROM AUTHOR]

In low-permeability fractured reservoirs, there is a generalized fluid displacement between the replacement fluid in the fracture and the matrix crude oil. This imbibition behavior plays a crucial role in the development of this type of reservoir. The experimental devices for studying static imbibition behavior are generally susceptible to air pollution on the surface of the test core and a long testing period; the experimental devices for studying dynamic imbibition behavior are generally unable to eliminate the driving action. A dual-purpose experimental setup and an experimental method for dynamic or static imbibition that can avoid the above defects were designed. A method of fracture fluid flow rate calculation and motor speed conversion is proposed, and the method is used to assist in setting the parameters of dynamic imbibition experiments. The device was applied to compare the experimental effects with the static imbibition bottle and the dynamic replacement imbibition, respectively, and the effect of fracture width on the dynamic imbibition of repellent oil was investigated. The results show that: the static imbibition recovery rate of the dynamic/static imbibition experimental device is 1.55 percentage points higher than that of the imbibition bottle; the dynamic imbibition recovery rate is 3–6 percentage points lower than that of the driving dynamic imbibition method, and it can reflect the influence of a single flow rate condition on the imbibition; imbibition in low-permeability fractured reservoirs is more likely to take place in the fracture in the interval of 50–100 μm in the width. [ABSTRACT FROM AUTHOR]

Mineral phases in which vanadium (V) and heavy-rare-earth elements (HREEs) coexist are rarely documented. Here, we report a new V-HREE-bearing silicate mineral species, wenlanzhangite-(Y), which is a vanadiferous derivate of jingwenite-(Y) [ Y 2 A l 2 V 2 4 + (S i O 4) 2 O 4 (O H) 4 ] coexisting with jingwenite-(Y) in bedded/massive ores at Yushui, South China. Wenlanzhangite-(Y) forms as a dark brown, 70–100 μm thick rim on a core domain of jingwenite-(Y), which occurs as 100–200 μm columnar crystals. The color, streak, luster, and hardness (Mohs) are dark brown, yellow-gray, vitreous, and ~4, respectively. Compared to jingwenite-(Y), wenlanzhangite-(Y) has higher vanadium and lower aluminum contents. Calculated on the basis of 8 cations, the empirical formula is (Y1.26Dy0.17Er0.11Gd0.09Yb0.09Nd0.09Sm0.06Sc0.04Ho0.03Ce0.02Tb0.02Tm0.02Pr0.01)Σ2.00 (V 1.46 3 + A l 0.54 ) Σ 2.00 V 2 4 + (S i O 4) 2 O 4 (O H) 4 , Which can be simplified to the ideal formula Y 2 V 2 3 + V 2 4 + (S i O 4) 2 O 4 (O H) 4 . Wenlanzhangite-(Y) is triclinic, with space group P 1 (#2), Z = 2, and unit-cell parameters a = 5.9632(7) Å, b = 9.599(1) Å, c = 9.9170(9) Å, α = 90.033(8)°, β = 98.595(2)°, γ = 90.003(9)°, and V = 561.28(10) Å3. Wenlanzhangite-(Y) is approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification (IMA2022-142). The structure of wenlanzhangite-(Y) is composed of a-axis-oriented chains of [VO6] octahedra consisting of edgesharing octahedra linked by insular [SiO2] tetrahedra, leaving open channels occupied by rare earth elements. Observed compositional variation and crystal structure demonstrate that V3+ can substitute for Al3+ in jingwenite-(Y), forming wenlanzhangite-(Y). The occurrence of wenlanzhangite-(Y) indicates a relatively more reducing hydrothermal environment, causing a reduction of V5+ in oxidized fluids to V3+ and thus represents a useful proxy for tracing the redox state of ore formation. [ABSTRACT FROM AUTHOR]

Impedance matching and attenuation principles are decisive for electromagnetic wave (EMW) absorption materials to achieve wider absorption bandwidth and higher strength absorption. By designing macrostructures to obtain metamaterials and tuning microstructures of absorption materials, impedance matching characteristic and absorption performance can be readily improved. In this paper, three-dimensional (3D) printing technology as well as precursor infiltration and pyrolysis (PIP) method were utilized to fabricate Al 2 O 3 /carbon nanotubes/SiC nanowires/SiOC composites with twisted cross metamaterial structures, where carbon nanotubes (CNTs) acted as a nucleating agent to obtain SiC nanowires (SiCnw) and as conductive phase to form conductive net structure, thus improving the dielectric and conductive loss of the composites. The Al 2 O 3 /CNT/SiCnw/SiOC composites achieved a minimum reflection coefficient (RC min) value of −56.84 dB (99.999%) at 12.2 GHz with a thickness of 2.8 mm and the effective absorption bandwidth (EAB) ranges from 8.2–12.4 GHz with a thickness of 3.2 mm, covering the whole X-band. The excellent EMW absorption performance of the composite with metamaterial structure makes it possible to be practically applied. Unlabelled Image • Novel twisted cross metamaterial structures were successfully achieved by 3D printing. • Precursor infiltration and pyrolysis process was conducted to generate SiC nanowires@Carbon nanoutbes on the ceramics. • The introduced SiC nanowires@Carbon nanoutbes significantly enhance the dielectric and conductive loss of the composites. • The designed metamaterial structures contribute to the enhanced absorbing performance. [ABSTRACT FROM AUTHOR]

• S-doped Co-Fe microsphere arrays developed on Ni foam (Co-Fe-S NFs@MS/NF) are fabricated. • The synergistic effects among Fe, S and Co enable superior OER activity in basic environments. • An in-situ electrochemical oxidation-induced activation mechanism of OER is proposed. • Real active phases of Co-Fe-S NFs@MS/NF during OER in alkaline conditions are identified. Herein, S-doped Co-Fe hybrid films with unique 3D porous microsphere arrays stacked by ultrathin nanoflakes directly grown on nickel foam (Co-Fe-S NFs@MS/NF) are synthesized via a single-step co-electrodeposition strategy. The synergistic effects among Fe, S and Co enable superior oxygen evolution reaction (OER) catalytic activity in basic environments. Impressively, this hybrid material can achieve further enhanced OER catalytic performance with surface self-assembly through in-situ electrochemical oxidation activation in both gentle alkaline (GA: 1.0 M KOH at 298 K) and industrial alkaline (IA: 30 wt.% KOH at 353 K) water electrolysis conditions. The transition processes are revealed in detail regarding the chemical, structural, and catalytic properties of the catalysts served in the GA and IA conditions. The pristine quasi-amorphous Co-Fe-S is found to partially transform into crystallized Co(Fe)OOH in the GA condition, while it remains amorphous nature in the IA condition. The enhanced OER activity is attributed to the formation of active Co(Fe)OOH species with massively proliferated specific surface area, optimized electronic structure, and accelerated kinetics. The activated Co-Fe-S NFs@MS/NF exhibits excellent OER activity, achieving 10 and 500 mA cm−2 at ultralow potentials of 1.453 (iR corrected) and 1.517 V with outstanding durability in the GA and IA conditions, respectively. For full water splitting, the assembled two-electrode system based on the Co-Fe-S NFs@MS/NF anode and a Co-S based cathode affords voltages of only 1.518 and 1.685 V to robustly deliver 10 and 500 mA cm−2 in GA and IA conditions over 200 h, respectively. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Heat pipes are widely used in thermal management due to their high heat transfer coefficient. However, traditional heat pipes conduct heat bidirectionally, depending on the temperature at both ends of the pipe. This can lead to the transfer of external heat back into the system at high ambient temperatures, reducing system performance and potentially damaging devices. To overcome this drawback, a thermal diode with thermal rectification in the horizontal direction based on a novel check valve and modified wick is proposed, and its thermal performances are experimentally investigated. Results show that the thermal diodes with filling ratio of working fluid less than 40% can achieve thermal rectification. The best thermal rectification coefficients of filling ratio of 10%, 20%, 30%, 40% and 50% are 3.422, 4.528, 4.238, 2.601 and 1.336, respectively. The thermal diode with filling ratio of 20% can reach the maximum thermal rectification ratio (4.528) under the heating power of 20W. [ABSTRACT FROM AUTHOR]

A series of V O -tunable NiFe-(oxy)hydroxides deposited on nickel foams (V O -NiFe/NF) were controllably manipulated, their electrochemical OER performance exhibited a volcano-type relationship with the percentage of V O , and positive relativity with the Ni3+/Ni2+ ratio. [Display omitted] NiFe-(oxy)hydroxides are the most active transition metal oxide electrocatalysts for oxygen evolution reaction (OER) under the alkaline media. Herein, we controllably manipulated oxygen vacancy (V O)-tunable NiFe-(oxy) hydroxides that their OER performances possessed a volcano-type relationship with V O concentration, positively-correlated with Ni3+/Ni2+ ratio. Theoretical simulations further unearthed the enhanced activation and dissociation of H 2 O by the inserting of V O. As a result, the optimal sample featuring the Ni3+/Ni2+ ratio of 30.3 % and V O of 23.8 % exhibited the overpotential of 243 mV at the current density of 100 mA cm–2, simultaneously lasting 120 h durability without any attenuation, exceding the most reported NiFe-(oxy)hydroxides. This work offers an innovative view to understand the OER performance using hypervalent Ni ratio induced by V O defects. [ABSTRACT FROM AUTHOR]

The Kaladawan iron deposit is located in the North Altyn Tagh and exhibits occurrences of iron ore bodies at the contact zone between Ordovician magmatic rocks (basalts, rhyolite, and granodiorite) and marble. However, controversy persists regarding the genetic classification and metallogenic mechanism of this deposit. Through a field investigation, single mineral in situ geochemical analysis, whole-rock geochemical analysis, and Fe isotope determination, the following conclusions are made: (1) Ti-(Ni/Cr) and (V/Ti)-Fe diagrams indicate that the magnetite from all studied rocks underwent hydrothermal metasomatism, while (Ni/(Cr + Mn))-(Ti + V) and (Ca + Al + Mn)-(Ti + V) diagrams suggest a skarn origin for these magnetites. Therefore, it can be inferred that the Kaladawan iron deposit is skarn-type. (2) The iron ore exhibits similar rare-earth-element characteristics to the altered basalt. Additionally, the altered basalts (δ56Fe = 0.024~0.100‰) are more enriched in light Fe isotopes than the unaltered basalts (δ56Fe = 0.129~0.197‰) at the same location, indicating that the ore-forming materials of the Kaladawan iron ore are mainly derived from basaltic rocks. (3) According to the law of mass conservation and the intermediate Fe isotopic composition of the iron ore between the granodiorite and basalt, the hydrothermal fluid for the formation of iron ores was inferred to be derived from the late intrusive granodiorite. [ABSTRACT FROM AUTHOR]

As a novel type of additive manufacturing, three-dimensional (3D) printing can efficiently realize the manufacturing of ceramic devices with more sophisticated structures. In this study, the method combining digital light processing (DLP) 3D printing technology and modified ceramic precursor polysiloxane (PSO) was not only used to fabricate Al 2 O 3 ceramic devices with a gradient impedance bilayer structure, which consist of a cross-twist/flat structure with a torsion angle of 60°, but also to prepare needle-like SiC nanowire absorbents grown in situ to further endow the ceramic functional characteristics. The microstructure was regulated by different times of impregnation, light-curing, and thermal treatment of ferrocene-modified PSO, and Al 2 O 3 /SiCnw/SiOC composites with different electromagnetic absorption properties were prepared. We found that the Al 2 O 3 /SiCnw/SiOC composite (sample 1400–2) exhibited the optimal microwave absorption performance when it was immersed and light-cured twice, which was ascribed to its comprehensive satisfaction of the impedance matching and attenuation characteristics. When the thickness of sample 1400–2 was as thin as 2.5 mm, the minimum reflection coefficient (RCmin) reached −44.35 dB, indicating that more than 99.9990% of the electromagnetic waves could be absorbed. As the thickness increased to 2.8 mm, the effective absorption bandwidth (EAB) in the X-band was 3.6 GHz, which indicated that the effective coverage rate was as high as 85.7%. The results indicate that the generation of the stacking fault, dipole and interfacial polarization of the Al 2 O 3 /SiCnw/SiOC composites, and increasing conductivity contribute to the promotion of dielectric loss. Thus, the Al 2 O 3 /SiCnw/SiOC composite with bilayer gradient impedance structures is a good candidate for stealth radar wave absorption. [ABSTRACT FROM AUTHOR]

Herein, we perform a facile one-step deep eutectic solvent electrodeposition approach to fabricate a series of S-doping highly porous Co-S films by in situ grown on Ni foam (Co-S/NF), which exhibits a superior catalytic activity and robust nature for both oxygen and hydrogen evolution reaction (OER and HER) in alkaline media. The doping of S is evidenced to induce a structural and size transition on the Co deposited layer, which leads to a significant increase on the electrochemical surface area and more accessible active sites for enhancing the catalytic activity. The formation of oxygen deficiencies-rich Co-O/OH species with a phase transformation from Co-S species is noticed during OER. Benefiting from the merits of in situ growth, the Co-S films obtained at an optimal S doping level (denoted as Co-S-50/NF) can robustly drive high current densities of 100 and 500 mA cm−2 with low overpotentials of 322 and 368 mV for OER, and 124 and 155 mV for HER. The water electrolyzer assembled with Co-S-50/NF requires only 1.79 and 2.08 V to reach 100 and 500 mA cm−2 in 1.0 M KOH, and 1.72 V to achieve 500 mA cm−2 in 30 wt% KOH at 353 K for over 150 h. • Self-supported highly porous Co-S films grown on Ni foam (Co-S/NF) are fabricated. • The Co-S/NF exhibits strong structural integrity with abundant active sites. • The Co-S/NF serves as efficient and durable catalyst for full water splitting. • Mechanism of Co, S-doping on enhancing the catalytic activity of Co-S/NF is proposed. [ABSTRACT FROM AUTHOR]