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The prediction of power equipment activity plays a vital role in optimizing power resource dispatch, ensuring supply and demand balance, and guiding network planning and management. However, due to the complex nonlinear, multi-scale, and multivariate characteristics of power grid communication networks service activity (PCNSA) data, it is often challenging to capture its intrinsic patterns and dynamic changes through a simple model. To address this issue, this paper proposes a power grid communication network service activity prediction method based on convolutional neural network, bidirectional gated recurrent unit, and attention mechanism, referred to as CBGA. CNN is used to extract features from time-series data, BiGRU is used to capture long-term feature changes in the data, and the attention mechanism is used to enhance the extraction of important information. To validate the performance of the proposed method, experiments and comparisons were conducted on three real power grid communication network datasets, demonstrating that our method shows better performance and robustness. [ABSTRACT FROM AUTHOR]

Additive manufacturing has revolutionized manufacturing across a spectrum of industries by enabling the production of complex geometries with unparalleled customization and reduced waste. Beginning as a rapid prototyping tool, additive manufacturing has matured into a comprehensive manufacturing solution, embracing a wide range of materials, such as polymers, metals, ceramics, and composites. This paper delves into the workflow of additive manufacturing, encompassing design, modeling, slicing, printing, and post-processing. Various additive manufacturing technologies are explored, including material extrusion, VAT polymerization, material jetting, binder jetting, selective laser sintering, selective laser melting, direct metal laser sintering, electron beam melting, multi-jet fusion, direct energy deposition, carbon fiber reinforced, laminated object manufacturing, and more, discussing their principles, advantages, disadvantages, material compatibilities, applications, and developing trends. Additionally, the future of additive manufacturing is projected, highlighting potential advancements in 3D bioprinting, 3D food printing, large-scale 3D printing, 4D printing, and AI-based additive manufacturing. This comprehensive survey aims to underscore the transformative impact of additive manufacturing on global manufacturing, emphasizing ongoing challenges and the promising horizon of innovations that could further elevate its role in the manufacturing revolution. [ABSTRACT FROM AUTHOR]

Exploration and development effects of Lucaogou Formation laminated shale are not ideal in the Santanghu Basin, and the reasons are not clear. Therefore, in this study, laminated and massive shales were systematically sampled, and experiments of cryogenic adsorption of nitrogen and multi‐dimensional nuclear magnetic resonance comparison were carried out. The results show that Lucaogou Formation shale is rich in volcanic ash and low content of clay, which can be divided into tuff, dolomite, tuffaceous dolomite, dolomitic tuff, and other lithologic types. The laminar structure is developed in tuffaceous dolomite and dolomitic tuff. The pores of Lucaogou Formation shale with a diameter of more than 10 nm can be used as an effective storage space for movable oil. The oil saturation and mobile oil ratio of laminated shale are lower than that of massive shale. Movable oil is controlled by carbonate content, and the higher the content, the higher the proportion of movable oil. Millimetre laminae are rich in organic matter and have poor interlaminar pore connectivity, which leads to strong adsorption capacity for oil. Therefore, the migration of oil between laminae is blocked, and oil mainly distributes or migrates in the bedding plane between laminae in laminated shale, which cannot be used as favourable reservoirs. [ABSTRACT FROM AUTHOR]

Aged battery is prone to fire accidents. Thermal stability change of battery subjected to inhomogeneous aging is studied in this manuscript by accelerating rate calorimeter. The results indicate that thermal runaway time decreases for aged batteries. Solid electrolyte interphase and lithium plating suppress and accelerate onset exothermic side reactions. Transition metal dissolution accelerates positive electrode decomposition and oxygen release. T TR of aged batteries decreases compared to fresh battery. Microscopic changes of negative electrodes for batteries cycled at high and low temperature are inhomogeneous. T onset for batteries cycled at low temperature decreases as lithium plating covers all of the negative electrode surface. T onset for batteries cycled at high temperature and with 100% state of charge (SOC) increases. This is the same to battery stored at high temperature. Local lithium plating affects thermal stability of battery with 100% SOC less. However, T onset for batteries with SOC lower than 50% SOC and subjected to local lithium plating decreases compared to fresh battery. Local lithium plating accelerates onset exothermic side reactions for battery with SOC lower than 50% SOC. The results of this manuscript are important to thermal runaway prevention for batteries in their whole operation life. [Display omitted] [ABSTRACT FROM AUTHOR]

Ratoon rice production has been an emerging cropping system to increase food quality and productivity worldwide. Efficient monitoring of ratoon rice aboveground biomass (AGB) over large areas is valuable for precision agriculture, as AGB is closely related to crop grain yield and quality. Unmanned aerial vehicle (UAV) remote sensing has opened an unprecedented opportunity to efficiently monitor crop AGB instead of labor-intensive ground measurements. Vegetation indices (VIs)-based approach for estimating AGB is easily affected by background materials and often suffers saturation problems at high AGB levels. Although the combined use of UAV-collected structural and spectral features can alleviate these problems to some extent, uncertainties on the AGB estimation still exist for crop with significant difference in canopy architecture and AGB composition throughout the growing season (e.g., ratoon rice). There is a hypothesis that the combination of spectral, textural and structural features can improve ratoon rice AGB estimations across different developmental stages. Therefore, the utility of UAV-based spectral, textural and structural features were quantified in estimating ratoon rice AGB at field level with contrasting agronomic treatments (i.e., nitrogen fertilizer and stubble height), in which multiple linear regression (MLR) and gaussian process regression (GPR) methods were applied and compared. Results showed that (1) each feature had its own respective limitation: specifically, spectral and textural features exhibited insufficient sensitivity to AGB variability of remaining stubbles or stem at early stage and suffered saturation problem at grain filling stage; structural features were difficult to detect the emergence of panicles from panicle initiation to heading stages; (2) the combination of three types of features can complement each other and achieved the highest accuracy using GPR method: the combination of spectral, structural and textural features achieved the best estimation accuracy for estimating ratoon rice AGB with an R2 of 0.94 and RMSE of 81.4 g m−2 across different developmental stages, which significantly improved the model performance compared to the combination of spectral and textural features (R2 = 0.56, RMSE = 170.2 g m−2) and the combination of spectral and structural features (R2 = 0.86, RMSE = 138.8 g m−2). In summary, this study provides a novel approach for efficiently estimating ratoon rice AGB at field level, which is critical for timely decision making (e.g., determine when and where to apply fertilizer or pesticide) in precision agriculture. [ABSTRACT FROM AUTHOR]

Lodging is a common phenomenon in maize production, which seriously affects its yield, quality, and mechanical harvesting capacity. With good penetrating power, satellite radar can monitor crop growth even under cloudy weather conditions. In this study, a method based on the change in plant height before and after lodging in maize is proposed to calculate the lodging angle and monitor the lodging degree by using dual-polarization Sentinel-1A data. The results show that the optimal sensitive polarization combinations of maize plant height before and after lodging are VH/VV and VV, respectively. The lodging angle is calculated using the plant height inversion results before and after lodging. The overall accuracy of classifying lodging grade of maize is 67%. The proposed model based on lodging angle could effectively mapped the maize lodging range on a regional scale and classify the lodging grades. [ABSTRACT FROM AUTHOR]

• The 9α-hydroxyandrost-4-ene-3,17-dione is a key intermediate of steroid drugs. • A nonionic surfactant is selected based on hydrophilic-lipophilic balance values. • Polyoxyethylene (10) nonylphenyl ether enhanced phytosterol solubility by 12.1-fold. • The 9α-hydroxyandrost-4-ene-3,17-dione molar yield increased to 42.5%. The 9α-hydroxyandrost-4-ene-3,17-dione (9α−OH-AD) is a key intermediate for synthetizing steroid pharmaceutical compounds. It is bioconverted by Mycobacterium sp. LY-1 from phytosterols. During biotransformation, the low solubility of phytosterols in water limits 9α−OH-AD production. In the present work, polyoxyethylene (10) nonylphenyl ether (TX-40), a nonionic surfactant, was first used to enhance phytosterol solubility during 9α−OH-AD biotransformation. In the presence of 0.7% TX-40, phytosterol solubility was increased 12.1-fold, and the 9α−OH-AD molar yield reached 42.5% at the phytosterols concentration of 15 g/L, an increase of 217.2% over controls. The improvement is sufficient to replace the traditional process of adding soybean oil. Scanning electron microscopy showed that the extracellular membrane-like structure was loosened by TX-40, but cells maintained their integrity. The fatty acid profile of Mycobacterium sp. LY-1 cells revealed that TX-40 altered the composition of the cell membrane and improved its permeability. The transcript levels of key enzymes involved in cell membrane lipid synthesis were downregulated significantly upon TX-40 addition compared with controls. These results demonstrated that the increase in product molar yield by TX-40 was primarily related to easier substrate transportation across the cell membrane of Mycobacterium sp. LY-1. [ABSTRACT FROM AUTHOR]

This letter presents a design method of resistance reactance hybrid continuous power amplifier based on reconfigurable devices and CG2H40010F. The power amplifier combines resistive‐reactive inverse F‐class power amplifier (RRIFPA), resistive‐reactive J‐class power amplifier (RRJPA), and resistive‐reactive F class power amplifier (RRFPA). We utilize the principle of low‐pass filters to control the impedance of multi‐frequency harmonics, and use the reconfigurable device SMP1345‐079LF to expand the bandwidth of the power amplifier. This article designs and produces a 1–4 GHz broadband power amplifier. The simulation and measurement results show that within the entire frequency range of 1–4 GHz, the Drain efficiency is between 53.6 and 72.1% $ \% $, the output power is between 40.1 and 42.6 dBm, the gain is between 10.1 and 12.6 dB, and the relative bandwidth is up to 120% $ \% $. [ABSTRACT FROM AUTHOR]

Local lithium plating significantly affects battery safety and cycle life. This study investigated the aging of lithium-ion batteries (LIBs) cycled at low temperatures after high-temperature and local lithium plating evolution. Nondestructive and destructive methods were employed to study battery degradation and electrode changes. The results indicate that the surface changes of the negative electrode in parts 1 and 2 are due to solid electrolyte interphase growth and lithium plating, respectively. Battery aging at 50 °C for 18,650-type LIB is inhomogeneous. Local lithium plating is consumed during cycling. The aging of the battery cycled at −10 °C after 50 °C is slower compared to those cycled at constant high and low temperatures. Lithium plating occurs when plated lithium already exists. Battery aging for 18,650-type batteries is path dependent because the electrode changes for batteries cycled at low temperatures after high temperatures are similar to those for batteries cycled at high temperatures. The battery aging in this study was mainly caused by lithium plating in part 2 of the negative electrode. The aging of the 18,650-type battery is governed by Cannikin's law. A high charging rate accelerates the battery aging at low temperatures. The aging rate of the battery charging at 0.6 C is higher than that of the battery charging at 0.8 C after dozens of cycles. The influence of charging rate on battery aging changed with cycling. • Battery aging at 50 °C is inhomogeneity. • Battery aging has memory effect. • Battery aging is subjected to Cannikin Law. • Lithium plating is prone to occur at where plated lithium already occurred. • Influence of charging rate on battery aging changes with cycle. [ABSTRACT FROM AUTHOR]

Abstract In modern process industries, many parameters or states can be acquired with sensors, and these parameters or states often have a close relationship with operation conditions. Unfortunately, the process often operates under different modes, and labels thereof are often unknown. In practice, labeling for sampled data is expensive and time-consuming, so identifying the operation conditions of the industrial process is difficult. In addition, sampled data from the industrial system are always contaminated by outliers or noise. Therefore, a robust process monitoring method for the multimode process is particularly important and challenging. In this paper, a robust dictionary learning method is proposed for processes with multiple unknown modes. Firstly, by taking the sparsity of outliers into account, a robust dictionary learning method is proposed to identify and remove the outliers and noise in the sampled training data. Secondly, an iterative minimization algorithm is designed for solving the dictionary learning optimization program. Thirdly, based on the sparsity of the sparse code, we partition the sparse code into different clusters via spectral clustering method, and then the dictionary is divided into some sub-dictionaries according to the cluster results of sparse code. Lastly, when a new sample is generated, we reconstruct it under different sub-dictionaries, and the smallest dictionary reconstruction error is calculated as a classifier for process monitoring and fault detection. To evaluate the validity and effectiveness of the proposed monitoring approach, we conduct extensive experiments on a numerical simulation, the continuous stirred tank heater (CSTH) process, and an industrial aluminum electrolysis process, in comparison with several state-of-the-art methods. The experimental results demonstrate that the proposed method is able to provide satisfying monitoring results, and it is also robust to outliers in the sampled training data. It is worth mentioning that the proposed method is an unsupervised learning method, therefore, it is more suitable for the process monitoring of real industrial systems. [ABSTRACT FROM AUTHOR]

We focus on a dual-functional multi-input-multi-output (MIMO) radar-communication (RadCom) system, where a single transmitter with multiple antennas communicates with downlink cellular users and detects radar targets simultaneously. Several design criteria are considered for minimizing the downlink multiuser interference. First, we consider both omnidirectional and directional beampattern design problems, where the closed-form globally optimal solutions are obtained. Based on the derived waveforms, we further consider weighted optimizations targeting a flexible tradeoff between radar and communications performance and introduce low-complexity algorithms. Moreover, to address the more practical constant modulus waveform design problem, we propose a branch-and-bound algorithm that obtains a globally optimal solution, and derive its worst-case complexity as function of the maximum iteration number. Finally, we assess the effectiveness of the proposed waveform design approaches via numerical results. [ABSTRACT FROM AUTHOR]

The problem of service matching and scheduling in cloud manufacturing (CMfg) is complex for different types of manufacturing services. 3D printing, as a rapidly developing manufacturing technology, has become an important service form in the CMfg platform due to its characteristics of personalized manufacturing. How to solve the task scheduling problem for distributed 3D printing services in CMfg needs further research. In this paper, a service transaction model of 3D printing services in CMfg is built. Based on the service transaction model, we propose 3D printing service matching strategies and matching rules of different service attributes, including model size, printing material, printing preciseness, task cost, task time, and logistics. To reduce the delivery time of tasks from service suppliers to service demanders, a 3D printing service scheduling (3DPSS) method is proposed to generate optimal service scheduling solutions. In 3DPSS, optimization objective, constraints, and optimization algorithm are presented in detail. Experimental results show that the average task delivery time of 3DPSS is shorter than that of typical scheduling methods, such as particle swarm optimization, pattern search, and sequential quadratic programming, when the amounts of tasks change. [ABSTRACT FROM AUTHOR]

• 3D printing mortar is prepared by using bauxite tailings as fine aggregate instead of natural sand. • The addition of bauxite tailings can greatly improve the buildability of 3D printing mortars. • The mechanical properties of the 3D printing mortar are the best when the bauxite tailings replacement ratio is 35%. • Using bauxite tailings to make 3D printing mortar is feasible and environmentally friendly. Using tailings to replace natural resources to prepare building materials is not only effectively alleviate the pressure of natural resource shortage, but also has important significance for environmental protection. This study aims to explore the applicability of bauxite tailings as fine aggregate instead of natural sand to prepare 3D printing mortar. The workability, rheological properties, buildability, hydration properties and mechanical properties of 3D printing mortar using bauxite tailings instead of 15%, 25%, 35% and 45% of natural sand were determined. The results show that the incorporation of tailings reduces the fluidity, slump and setting time of the 3D printing mortar, but delays the hydration process of the cementitious material. The rheological analysis reveals that the incorporation of tailings can significantly improve the static yield stress, dynamic yield stress, plastic viscosity and thixotropy of 3D printing mortar. With increasing tailings content, the macroscopic deformation and structural deformation rate of 3D printed components are gradually decreased. The compressive strength and flexural strength of 3D printing mortar are increased first and then decreased with increasing tailings content. Based on the test results, it is determined that the optimal ratio is that the mass ratio of tailings to replace natural sand is 35%, which can make the 3D printing mortar obtain good workability and high mechanical strength. Overall, it is feasible to use bauxite tailings to prepare 3D printing mortar, which optimizes both buildability and mechanical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • OBS was detected in all 11 tissues and intestinal contents. • The liver exhibited the highest OBS level, followed by the small intestine, lung, and kidney. • Gender of mice will affect tissue distribution of OBS. • Different distribution characteristics were observed for three isomers of OBS. Environmental risks caused by emerging per- and polyfluoroalkyl substances (PFASs) have attracted increasing attention. As an important substitute for perfluorooctane sulfonate (PFOS), sodium p -perfluorous nonenoxybenzene sulfonate (OBS) is widely used as a firefighting foam additive and oil recovery agent in China. This study reported the tissue distribution of OBS in KM mice that were administered a dose of OBS at 10 µg/day via daily oral gavage for 7, 14, or 28 days. During exposure, gender-based differences were observed in body weight changes and tissue distribution of OBS. Liver exhibited the highest concentrations (males: 12.57 ± 1.80 µg/g; females: 11.80 ± 5.32 µg/g) and tissue/blood ratios and contributed more than 50% to the whole-body burden of OBS in both male and female mice, showing its ability to enrich PFASs. Furthermore, there were certain differences in the distribution characteristics of the three OBS isomers. Based on its bioaccumulation potential and widespread use, further studies are required on the human exposure risks of OBS. [ABSTRACT FROM AUTHOR]

Poly(styrene-maleic anhydride) functionalized graphene (FG) and functionalized carbon nanotubes (FCNTs) were fabricated using in situ polymerization. The FG and FCNTs were used in the in situ ring-opening polymerization of ε-caprolactam to form polyamide 6 (PA6)/FG/FCNTs composites. Both PA6 and the composite fibers were melt-spun in a piston spinning machine. The structure and properties of the composites and the fibers were characterized. The experimental results demonstrate that the mixture of graphene and carbon nanotubes exhibits good dispersion in a PA6 matrix. No obvious aggregation of graphene or CNTs was observed inside the composite fibers. The mechanical properties of PA6 are improved by inserting FG/FCNTs into the composite fibers, in particular, the tensile strength of composite fiber containing FG (0.2 wt%)/FCNTs (0.3 wt%) is 2.4 times that of pure PA6, and Young's modulus is 132 % higher than that of the control. The crystallinity of the composite fibers is also enhanced. With the improvement of the tensile strength and Young's modulus of PA6, its application will be expanded. [ABSTRACT FROM AUTHOR]

Abstract: Glasses with molar composition of (100-x)B2O3-x[0.5 BaO–0.5 ZnO], x=40, 50, 60, 70 were prepared from the melts of ZnO, BaCO3 and H3BO3 mixture. The structure and thermal behavior were characterized by IR and Raman spectroscopy, DSC and Dilatometer. The investigation shows that the transition of the structural unit [BO4] (BIV) to [BO3] (BIII) happens when BaO and ZnO content x increases in the borate glass, resulting in fewer BIII–O–BIV bonds and more BIII–O–BIII bonds. At the same time, the diborate groups, which are found to be the predominant structural group of the glass with high B2O3 content, gradually changes into ring-type metaborate, pyro- and orthoborate groups. With increasing ZnO and BaO content x, the glass transition temperature (T g) and the softening point (T f) decreases, while linear expansion coefficient (α) increases, that comes from the weakening of the glass network. [Copyright &y& Elsevier]

• Hydration process including NG, I and D of composite binder was simulated according to hydration kinetics model. • Tailing size affected the hydration kinetics of composite binder. • Adding tailings reduced the hydration heat. • Bauxite tailing content exceeding 30% substantially impacted later hydration. To explore the influence of bauxite tailings particle size and content on the hydration process of cement-tailings composite binder, the hydration kinetics of blended cement containing activated bauxite tailings was investigated. Hydration heat of cement-bauxite tailings composite binder was measured at 20 °C. The Krstulovic–Dabic kinetics model was used to explore the kinetics of blended cement containing bauxite tailings. The hydration process of blended cement was analyzed by the X-ray diffraction (XRD). Results demonstrate that the induction period of the composite binder increased with increase in the bauxite tailings content. The hydration heat increased with increase in powder selection frequency of the tailings. The kinetics model could effectively simulate the hydration process of cement- bauxite tailings composite binder. With the increase of the tailings content, the value of α 1 decreased and that of α 2 increased. Calcined activated bauxite tailings could react with calcium hydroxide owing to the pozzolanic reaction. The calcium hydroxide content of the composite binder decreased compared with pure cement and decreased with increase in the bauxite tailings content, particularly for bauxite tailings incorporations exceeding 30%. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma (CCA) is a hepatobiliary carcinoma characterized by the differentiation of bile duct cells, and the patients with CCA often have a poor prognosis. Eukaryotic translation initiation factor 5A (eIF5A) is reported to have multiple biological activities. Targeted activation of ferroptosis may be a therapeutic strategy for cancer. Nevertheless, the effects of eIF5A and ferroptosis on CCA are still elucidated. Our study explored the effects of eIF5A in CCA, and the mechanisms also are studied. In this paper, TCGA database analysis suggested that eIF5A was upregulated in CCA, and high expression of eIF5A might predict a poor prognosis. Moreover, FANCD2, SLC7A11, and HSPB1 were significantly overexpressed in CCA. The results indicated that eIF5A was overexpressed in CCA tissues and cells. Further experiments demonstrated that eIF5A silencing decreased CCA cell activity and enhanced ferroptosis and mitochondrial apoptosis. In addition, upregulation of eIF5A showed the opposite effect on CCA cells compared with downregulation of eIF5A. Finally, the silencing of eIF5A could restrain the growth of xenografted tumors and promote ferroptosis. Overall, eIF5A enlarged CCA cell activity and attenuated ferroptosis and mitochondrial apoptosis. The results suggested that assessment of eIF5A might provide help for the diagnosis and treatment of CCA. [ABSTRACT FROM AUTHOR]

• It's the first time bis-coumarin was used as fluorophore to design fluorescent probe for detecting palladium. • The fluorescent probe for detecting palladium has a quite low the limit of detection as 40.0 nM. • The probe can distinguish and detect Pd0 and Pd2+/Pd4+ with the help of NaBH 4. • The probe can quantitatively detect palladium in lake water and Yellow River water. • The removal effect of palladium residue on beaker by different cleaning methods was discussed. A catalytic fluorescent probe based on V-shaped bis-coumarin has been designed and synthesized for detection of palladium (Pd). The detection mechanism of the probe is based on palladium-catalyzed Tsuji‒Trost reaction process and photoinduced electron transfer (PET), which can distinguish and detect palladium (0, +2/+4) in different valence states under different conditions. The fluorescence intensity of the probe enhances after adding the palladium in about 10 min at room temperature. The limit of detection (LOD) of the probe is as low as 40.0 nM (4.2 ng/g), and it has good selectivity and high sensitivity. Apart from that, it has been successfully applied to detection of palladium in environmental waters. [ABSTRACT FROM AUTHOR]

This study monitored 20 organophosphate esters (OPEs) in water and sediment from three typical mariculture bases (Yunxi Marine Ranching (YX), Hangzhou Bay (HZB), and Zhelin Bay (ZLB)) and Meiliang Bay (MLB) of Taihu Lake in China, focusing on the spatial distribution and sources of OPEs. Moreover, the occurrence and risk of OPEs in fishes from ZLB were evaluated. The ∑OPE concentrations in waters followed the order MLB (591 ng/L) > YX (102 ng/L) > HZB (70.0 ng/L) > ZLB (37.4 ng/L), with tri(1-chloro-2-propyl) phosphate (TCIPP), triethyl phosphate (TEP), and tri(2-chloroethyl) phosphate (TCEP) being the dominant OPEs. Significantly higher ∑OPE concentrations were found in sediment in MLB compared to the other three areas with similar levels. The decreasing concentrations of OPEs from nearshore to offshore areas in HZB and MLB indicated that terrigenous input is the main source of OPEs. The even distribution of OPEs in YX and ZLB combined with PCA analysis suggested ship traffic or aquaculture activities are also potential sources. The ∑OPE concentrations in fishes ranged from 0.551–2.45 ng/g wet weight, with TCIPP, tri-phenyl phosphate (TPHP), and TCEP being the main OPEs. Hydrophobicity was a key factor affecting the sediment-water distribution coefficients and the bioaccumulation factors of OPEs. The human exposure to OPEs through consumption of fishes from ZLB had a low health risk. [Display omitted] • Ten OPEs were ubiquitous in water and sediment of the four aquaculture areas. • TCIPP, TCEP, TEP, and TEHP were dominated in water and sediment, while TCIPP, TCEP, and TPHP were the most abundant in fish. • OPE concentrations in water followed the order Meiliang Bay > Yunxi Marine Ranching > Hangzhou Bay > Zhelin Bay. • River input, ship traffic, and aquaculture activities are the main sources of OPEs in coastal mariculture water. • OPEs in fish of Zhelin Bay posed low risks to human health. [ABSTRACT FROM AUTHOR]

• The differences of diffraction intensity of different crystal planes indicated the regulating action of succinic acid. • The connection between the hydration properties and crystal morphology characteristics of α-HH was established. • Preparation of α-HH from phosphogypsum is a way to realize effective utilization of phosphogypsum. Using phosphogypsum (PG), a solid waste from the phosphoric acid industry, to prepare α-hemihydrate gypsum (α-HH) with cementitious properties is an effective approach to realize the extensive utilization of PG. In this study, succinic acid (SA) was used as a crystal modifier to prepare α-HH at a reaction temperature of 130 °C and a stirring speed of 300 rpm. The phase composition and hydration properties of the prepared products and the mechanism of action of SA were investigated. Results indicated that SA had an excellent morphological control on α-HH crystals prepared under hydrothermal conditions. With an increase in the concentration of SA, α-HH crystal shape transformed from long needle-like to shortly columnar, which was caused by the physical adsorption of SA on the crystal surface changed the growth rate of crystals in different directions. The hα-HH crystals prepared at a concentration of 4 mM with SA are short columnar with an aspect ratio of 2.32 and a compressive strength of 24.7 MPa. Furthermore, the hydration processes were determined by the joint contribution of water requirement and SA concentration, and SA was used not only as a crystal modifier but also as a retarder in the hydration process of α-HH. [ABSTRACT FROM AUTHOR]

Plantation forests provide critical ecosystem services and have experienced worldwide expansion during the past few decades. Accurate mapping of tree species through remote sensing is critical for managing plantation forests. The typical temporal behaviors and traits of tree species in satellite image time series (SITS) generate temporal and spectral features in multiple phenological stages that are critical to improve tree species mapping. However, the diverse input features, sequential relations and complex structures in SITS drastically increase the dimension and difficulty of spectral-temporal feature extraction, which challenges the capacity of many general classifiers not explicitly adapted for spectral-temporal learning. As a result, there is still a lack of a method that could automatically extract spectral-temporal features with high separability and regional adaptability from high-dimensional SITS for tree species mapping of plantation forests. Moreover, the effects of varying temporal resolution and feature combination on the plantation tree species mapping are under-explored. Here, we developed a multi-head attention-based method for automatically extracting spectral-temporal features with high separability based on a modified Transformer network (Transformer4SITS) for improved plantation tree species mapping. The end-to-end network model consists of a feature extraction module to learn deep spectral-temporal features from SITS and a fusion module to combine multiple features for improving mapping accuracy. We applied this method to two representative plantation forests in southern and northern China for tree species mapping. The results show that: (1) Transformer4SITS method could self-adaptively extract typical spectral-temporal features of key phenological stages (e.g., greenness rising and falling) from SITS, and achieved significantly improved accuracies by at most 15% in comparison with all four baseline methods (i.e., long short-term memory, harmonic analysis, time-weighted dynamic time warping, linear discriminant analysis); (2) time series with higher temporal resolution tended to produce more accurate species maps consistently across two sites, with their overall accuracies (OA) respectively increasing from 91.05% and 84.33% (60-day) to 94.88% and 88.72% (5-day), but the effect of high temporal resolution respectively leveled off around 90-day and 50-day resolution across two sites; (3) the mapping results using all available bands and two-band spectral indices outperformed the results using a subset of them, but with only modest increase in the accuracy (i.e., OA increased from 93.63% and 86.01% to 94.88% and 88.72%. This study thus provides a state-of-the-art deep learning-based method for improved tree species mapping, which is critical for sustainable management and biodiversity monitoring of plantation forests across large scales. [ABSTRACT FROM AUTHOR]

Southern corn leaf blight (SCLB) seriously threatens corn production. The timely and accurate monitoring of SCLB conditions (e.g., detection during the asymptomatic stage and severity classification during the symptomatic stage) is valuable for precision agriculture, because the application of pesticides depends on disease conditions. Compared with time-consuming and laborious field surveys, spectroscopy is a promising tool for plant disease monitoring. The unique advantages of combining multiple spectral enhancement features for monitoring rice and wheat diseases have been recognized. However, physiological and biochemical differences between maize leaves and rice and wheat leaves, along with the specific spectral response of SCLB, are likely to affect the performance of combining multiple spectral enhancement features. In addition, similar previous studies have not combined spectral slope features, i.e., first-order spectral derivatives (FSDs), with spectral bands (SBs) and spectral indices (SIs) and wavelet features (WFs) to improve plant disease detection. Thus, the performance of a method that combines FSDs, WFs, SBs, and SIs for SCLB asymptomatic detection, symptomatic detection, and symptomatic severity classification should be evaluated further. Here, the utility of combining SBs, SIs, WFs, and FSDs was quantified and evaluated in the asymptomatic detection, symptomatic detection, and symptomatic severity classification of SCLB. Various forms of spectral enhancement features that were sensitive to SCLB infection from the asymptomatic stage to the severe stage were first identified and combined using the RELIEF-F and sequential floating forward selection algorithms on the basis of two independent inoculation experiments. Finally, SCLB asymptomatic detection, symptomatic detection, and symptomatic severity classification models were developed and evaluated using the support vector machine algorithm. Results showed that combining FSDs with SBs, SIs, and WFs achieved the best performance in SCLB spectroscopic monitoring. (1) SCLB asymptomatic detection and symptomatic detection were moderately improved, i.e., overall accuracy (OA) and macro F1 (MF1) improved by ~ 1% to 2%. The OA of SCLB asymptomatic detection was 87.1% with an MF1 of 0.87, and that of symptomatic detection was 93.1% with an MF1 of 0.93. (2) SCLB symptomatic severity classification was significantly improved, i.e., OA and MF1 improved by ~ 7%. The OA of severity classification was 81.8% with am MF1 of 0.82. This study demonstrated that the complementary relationships among SBs, SIs, WFs, and FSDs could effectively improve SCLB spectroscopic monitoring. The proposed method provides a novel tool for large-scale SCLB spectroscopic monitoring. It has broad implications for assisting management decisions (i.e., when and where to apply pesticides and how much to apply) in precision agriculture. [ABSTRACT FROM AUTHOR]

• The optimal calcination regime for preparing calcium aluminate cement with Bayer red mud was determined. • The optimal proportion range of calcium aluminate cement without Bayer red mud was obtained by the simplex-centroid design method. • It was confirmed that the best performance of calcium aluminate cement was achieved when the content of Bayer red mud was 8%. Aiming at the problems of large discharge, the low utilization rate, and severe environmental pollution of Bayer red mud (BRM), this paper studied the feasibility of preparing calcium aluminate cement (CAC) with BRM as a raw material. The calcination regime of preparing CAC with BRM was investigated in the system of the CaO-Al 2 O 3 -SiO 2. The experiment was designed by the simplex centroid design method. The optimal proportion range of CAC without BRM was determined with the compressive strength as the index. In addition, the evolution of the microstructure was studied by scanning electron microscope (SEM). Results demonstrate that the phases CA, CA 2 , and C 2 AS were formed at a temperature of 1300 °C. It was determined that the best performance was obtained with a Bayer red mud content of 8% by X-ray diffraction (XRD) and hydration heat. Moreover, the strength of CAC designed with Bayer red mud could reach 45.8 MPa after curing for 14 days, which was 18.7 MPa higher than that of CAC prepared without BRM at the same curing age. [ABSTRACT FROM AUTHOR]

Formation water is produced during gas well production, which can seriously affect gas well productivity, especially in deep and ultradeep tight sandstone gas reservoirs. In this paper, we have studied the formation water production and geochemical properties of the ultradeep tight sandstone gas reservoir in the Cretaceous Bashijiqike Formation of the DK gas field in the Kuqa Depression. The results indicate that the formation water can be classified as condensate water, gas-water transition zone water, mixed water, and isolated formation water, all of which are acidic and of CaCl2 type, with increasing salinity or chloride ion content. Sodium/chloride ratio (ρNa+/ρCl-), metamorphic coefficient (ρ(Cl--Na+)/ρ(Mg2+)), desulfurization coefficient (100 × ρ S O 4 2 − / ρ C l − ), and trace elements concentration parameters show that the formation water was formed in a closed and reductive environment and experienced strong water-rock interaction. The formation water may have been influenced by early seawater, but it is not significant and is more likely to have been influenced by water seepage from the overlying gypsum strata. The Sr, H, and O isotopes reveal that the different types of formation water have good homology and are not affected by atmospheric precipitation, which is propitious to the preservation of natural gas. [ABSTRACT FROM AUTHOR]

• Primary aging mechanism changes from "dead lithium" to SEI growth at low temperature. • "Dead lithium" causes more capacity fading than SEI growth at low temperature cycle. • Plated lithium is inhomogeneity during long low temperature cycle. • Plated lithium is consumed at high temperature cycle after low temperature cycle. • Charge current affects battery aging at high temperature after low temperature most. Lithium plating is an important issue for lithium-ion battery safety and cycle life that can be caused by cycle at low temperature. In this study, we investigated battery aging over an extended low-temperature cycle and at high temperature after the low-temperature cycle. Nondestructive and destructive analysis methods were used to study battery electrochemical dynamics and changes to the materials, and the results indicated that battery aging over the extended low-temperature cycle could be divided into two stages. The mechanism of the first stage is that of "dead lithium," which causes significant capacity fading, whereas that of the second stage is solid electrolyte interphase (SEI) growth. It was also found that plated lithium accelerates battery aging at high temperature; part of it is intercalated into anode, another part of it reacts with the electrolyte, thus consuming the plated lithium. Thus, electrolyte decomposition and SEI growth are the primary aging mechanisms at high temperature after low-temperature cycling. The plated lithium content and charge/discharge rate affected plated lithium consumption during the high-temperature cycle. Plated lithium was not depleted for the battery with significant amounts of plated lithium or upon charging with high current and discharging with both high and low current when the state of health (SOH) decreased to 70%. The factors affecting battery aging ranked in order of importance are charge current > plated lithium content > high temperature > discharge current. [Display omitted] [ABSTRACT FROM AUTHOR]

7α,15α-diOH-Dehydroepiandrosterone (7α,15α-diOH-DHEA) is an important intermediate in the synthesis of steroid pharmaceutical compounds, and can be bioconverted from DHEA by Colletotrichum lini ST-1 . A microemulsion system can improve substrate bioavailability and may also minimize DHEA cellular toxicity as cells and substrate are retained in the water and oil phase respectively. In this study, several microemulsions with a different hydrophile lipophile balance were prepared and evaluated based on their stability and bioconversion efficacy. The yield of the best formula of 7α,15α-diOH-DHEA was 61.2%, which was 3.1 times that of the traditional water phase bioconversion system. This formula was further optimized using the Taguchi orthogonal experimental design, and the yield reached 73.3%. Due to less cellular toxicity of the substrate using the microemulsion system, the repeated-cycle bioconversion based on microemulsion using recycled cells was realized for the first time, and the overall 6-cycle production (41.5 g from 60 g DHEA) was 4.3 times that of the traditional method. This highly efficient microemulsion system, with improved cell sustainability as well as bioreactivity, may be expanded to the bioconversion of other insoluble and toxic substrates. [ABSTRACT FROM AUTHOR]

To bring zeolite membranes to commercial application, corresponding preparation technology must solve the following issues like low permeance, poor reproducibility, high manufacturing cost and scale-up etc., which is still a grand challenge. The imhomogeneous slurry-like mother liquor required by the preparation of pure silica CHA membrane makes this challenge even tougher. Herein, we realized facile and efficient preparation of pure silica CHA membrane for the first time. The use of an active silica source, ammonium hexafluorosilicate ((NH 4) 2 SiF 6), enabled facile membrane synthesis in a homogeneous mother liquor at mild temperature and ambient pressure. The replacement of conventional imhomogeneous slurry-like mother liquor with homogeneous mother liqour significantly improved the reproducibility of membrane synthesis and favored the formation of thin membrane. The high activity of (NH 4) 2 SiF 6 allowed low temperature synthesis at ambient pressure without sacrificing synthesis time. Moreover, gel-less synthesis significantly reduced material waste at no cost of selectivity and permeance. All these factors combined together resulted into a facile and reproducible preparation of thin pure silica CHA membrane with high material efficiency, energy efficiency and low equipment cost. Calcined pure silica CHA membrane exhibited outstanding CO 2 permence of 2.9 × 10−6mol/(m2⋅s⋅Pa) and high CO 2 –CH 4 selectivity ∼170. This efficient and facile preparation method has great potential for large scale synthesis. [Display omitted] • Active (NH 4) 2 SiF 6 as silica source enabled facile synthesis of all-silica CHA membrane at ambient pressure. • Homogeneous mother liquor facilitated synthesis reproducibility. • Gel-less synthesis significantly improved material efficiency. • Outstanding CO 2 –CH 4 separation performance obtained on much cheaper membrane. [ABSTRACT FROM AUTHOR]

In this paper, we propose the asymmetric multifractal detrending moving average analysis (A-MFDMA) method to explore the asymmetric correlation in non-stationary time series. The proposed method is applied to explore the asymmetric correlation of PM2.5 daily average concentration with uptrends or downtrends in China. In addition, shuffling and phase randomization procedures are applied to detect the sources of multifractality. The results show that existences of asymmetric correlations, and the asymmetric correlations are multifractal. Further, the multifractal scaling behavior in the Chinese PM2.5 is caused not only by long-range correlation but also by fat-tailed distribution, but the major source of multifractality is fat-tailed distribution. [ABSTRACT FROM AUTHOR]

• Template-free synthesis of sub-micron ZSM-5 membranes. • Al-deficient mother liquor ensured minimum membrane growth by a self-terminating mechanism. • Easy control of membrane thickness and high material efficiency. • Outstanding separation performance on butane isomers. Low-cost synthesis of thin zeolite membranes is extremely desirable, yet challenging. In this study, we realized template-free synthesis of ultrathin ZSM-5 membranes by conventional hydrothermal synthesis on regular ceramic support. The key is to choose a self-terminating mother liquor with high Si/Al ratio. The crystallization process (formation of ZSM-5 zeolite crystals and membrane) in this Al-deficient mother liquor is an Al-driven process. The crystallization led to fast depletion of Al in the mother liquor which triggered the termination of crystallization process in this template-free mother liquor. Therefore, the thickness of ZSM-5 membrane can be controlled easily by adjusting the ratio of mother liquor/membrane area, which is much simpler than membrane synthesis in conventional mother liquor. The obtained ultrathin MFI membranes exhibited outstanding separation performance for butane isomers. This strategy can also be applied to the synthesis of other types high-silica zeolite membranes. [ABSTRACT FROM AUTHOR]