The constantly growing demand for renewable electrical energy keeps the continuation of battery-related research imperative. In spite of significant progress made in the development of Na- and K-ion systems, Li-ion batteries (LIBs) still prevail in the fields of portative devices and electric or hybrid vehicles. Since the amount of lithium on our planet is significantly limited, studies dedicated to the search for and development of novel materials, which would make LIBs more efficient in terms of their specific characteristics and life lengths, are necessary. Investigations of less industry-related systems are also important, as they provide general knowledge which helps in understanding directions and strategies for the improvement of applied materials. The current paper represents a comprehensive study of cubic Li2Fe1−xCoxSeO compounds with an anti-perovskite structure. These solid solutions demonstrate both cationic and anionic electrochemical activity in lithium cells while being... [more]

At present, assessment techniques for the fracability of shale reservoirs, which rely on the formation of an effective fracture network, are scarce. Hence, in order to assess the fracability, it is critical to establish a quantitative correlation between the pattern of fracture distribution after fracture and fracability. The present investigation utilizes three-dimensional digital core technology and triaxial compression experiments to simulate the fracturing process in typical domestic shale reservoir cores. In addition to utilizing the maximum ball algorithm to extract fracture images, a number of other techniques are employed to compute the spatial quantitative parameters of the fractures, including least squares fitting, image tracking algorithms, and three-dimensional image topology algorithms. The introduction of the notion of three-dimensional fracture complexity serves to delineate the degree of successful fracture network formation subsequent to fracturing. A quantitative fra... [more]

With the notable achievements attained through the implementation of steam-assisted gravity drainage (SAGD), the vertical−horizontal steam drive (VHSD) emerges as a pivotal technological advancement aimed at significantly enhancing the efficiency of thin reservoir heavy oil recovery subsequent to steam cyclic stimulation. The inclusion of nitrogen assistance has proven effective in enhancing the efficacy of gravity drainage techniques in reservoir development. However, it is noteworthy that this method has only led to improvements in approximately 50% of the well groups within the observed field. The comprehensive evaluation index of VHSD was proposed, and as the objective function, it was determined that the greatest contribution to the VHSD technique lies in oil saturation, accounting for 40% of the overall evaluations. This differs from conventional SAGD operations, where reservoir thickness serves as the primary determinant. Building upon an enhanced physical simulation similarity... [more]

In this study, lithium was recovered from spent lithium-ion batteries through the crystallization of lithium carbonate. The influence of different process parameters on lithium carbonate precipitation was investigated. The results indicate that under the conditions of 90 °C and 400 rpm, a 2.0 mol/L sodium carbonate solution was added at a rate of 2.5 mL/min to a 2.5 mol/L lithium chloride solution, yielding lithium carbonate with a recovery rate of 85.72% and a purity of 98.19%. The stirring rate and LiCl solution concentration significantly impact the particle size of lithium carbonate aggregates. As the stirring rate increases from 200 to 800 rpm, the average particle size decreases from 168.694 μm to 115.702 μm. Conversely, an increase in the LiCl solution concentration reduces the lithium carbonate particle size, with an average particle size of only 97.535 μm being observed at a LiCl solution concentration of 2.5 mol/L. It was also observed that nickel and cobalt ions become incor... [more]

Rotating machinery fault diagnosis is of key significance for ensuring safe and efficient operation of various industrial equipment. However, under nonstationary operating conditions, the fault−induced characteristic frequencies are often time−varying. Conventional Fourier spectrum analysis is not suitable for revealing time−varying details, and nonstationary fault feature extraction methods are still in desperate need. Order spectrum can reveal the rotational−speed−related time−varying frequency components as spectral peaks in order domain, thus facilitating fault feature extraction under time−varying speed conditions. However, the speed−unrelated frequency components are still nonstationary after angular−domain resampling, thus causing wide−band features and interferences in the order spectrum. To overcome such a drawback, this work proposes a rotating machinery fault diagnosis method based on adaptive separation of time−varying components and order feature extraction. Firstly, the r... [more]

In this study, a falling weight impact test was conducted on EH690 steel specimens with V-notches using Digital Imaging Correlation (DIC). In conjunction with scanning electron microscopy (SEM), the plastic deformation and crack initiation processes were examined at the notch of the specimen under different impact energies (90 J, 120 J, 135 J and 150 J). ABAQUS was used to simulate the plastic deformation of an EH690 specimen. The results show that the strain at the notch tip experienced some elasticity and yielding as the load increased under different impact energies. The load remains unchanged or decreases slightly when a plastic hinge forms at the tip of the notch. According to the microscopic images, there are three areas on the fracture surface: a fiber area, a radiation area, and a shear lip area. With increasing deformation, a crack source forms in the middle of the V-shaped notch and propagates to the inside and outside surfaces of the sample. Cracks are primarily caused by du... [more]

In addressing the issue of climate change, the Chinese government has established a definitive objective to attain its peak carbon emissions by 2030 and strive for carbon neutrality by 2060. This effort aims to progressively achieve a state of net-zero carbon dioxide (CO2) emissions. In the given scenario, this research examines challenges in promoting low-carbon manufacturing (LCM) within the Chinese automotive sector, specifically in the context of Green Tech projects. In view of greater emphasis on environmental sustainability and technological innovation, this study aims to uncover challenges restraining the adoption of LCM in one of the world’s largest automotive markets, China. A three-step methodology was adopted by incorporating a literature review, the Delphi method, Interpretive Structural Modeling (ISM), and MICMAC analysis. In the first stage, relevant articles were selected scientifically to identify the main challenges in previous studies by following the relevant keyword... [more]

This study investigates the effectiveness of microwave treatment (MW) on the antifungal properties of Norway spruce wood and the leaching of preservatives. Given the environmental and health concerns about conventional wood preservatives, this study evaluates microwave treatment as a sustainable pretreatment to limit the leaching of preservatives from wood. In the experiment, wood samples were treated with microwaves at five different energy levels before being impregnated with copper−ethanolamine- and boron-based preservatives. We assessed preservative retention by leaching tests and assessed the resistance of the wood to fungal attack. The results show that MW treatment improves the uptake and fixation of preservatives, reduces leachability, and significantly improves the durability of an otherwise perishable wood against fungal attack. This study emphasises the potential of microwave treatment for wood preservation. It offers an environmentally friendly approach to extending the lif... [more]

Wildfire is one of the most critical natural disasters that poses a serious threat to human lives as well as ecosystems. One issue hindering a high accuracy of computer vision-based wildfire detection is the potential for water mists and clouds to be marked as wildfire smoke due to the similar appearance in images, leading to an unacceptable high false alarm rate in real-world wildfire early warning cases. This paper proposes a novel hybrid wildfire smoke detection approach by combining the multi-layer ResNet architecture with SVM to extract the smoke image dynamic and static characteristics, respectively. The ResNet model is improved via the SE attention mechanism and fully convolutional network as SE-ResNet. A fusion decision procedure is proposed for wildfire early warning. The proposed detection method was tested on open datasets and achieved an accuracy of 98.99%. The comparisons with AlexNet, VGG-16, GoogleNet, SE-ResNet-50 and SVM further illustrate the improvements.

The development of power grids is hindered by the limited transmission capacity of cable equipment, necessitating the accurate prediction of dynamic ampacity for cable expansion. This study focuses on the 110 kV cable intermediate joint, employing radial and axial inversion techniques for real-time conductor temperature inversion. Utilizing the Prophet time series model, we predict environmental changes and propose a dynamic ampacity evaluation method for cable intermediate joints. Experimental validation confirms the model’s accuracy, with prediction errors under 10 K, demonstrating its potential for enhancing cable system reliability and power grid development.

The detection of metal ions is an option for maintaining water quality and diagnosing metal ion-related diseases. In this study, we successfully detected metal ions using fluorescent peptides in water. First, we prepared seven linear (L1−L7) and seven cyclic (C1−C7) peptides containing two pyrenyl (Pyr) units and assessed the response to various metal ions by fluorescence. The results indicated that C1, which contains a hexameric cyclic peptide moiety consisting of Pyr and Gly units, did not show a fluorescent response to metal ions, while the linear L1 corresponding to C1 showed a response to Cu2+, but its selectivity was found to be poor through a competition assay for each metal ion. We then assessed C2−C7 and L2−L7, in which Gly was replaced by His units at various positions in the same manner. The results showed that C2−C7 responded to Cu2+ in a manner dependent on the His position. Additionally, superior selectivity was observed in C7 through a competition assay. These results de... [more]

CNT-NH2-Cu-BTC was prepared via hydrothermal synthesis for the adsorption and separation of CO2/CH4 mixtures with 2, 6, and 10% multiwalled carbon nanotube (MWCNT) additions. NH2-BTC composites were synthesized by changing the organic ligand and adding NH2-BDC (15, 25, 35, and 45%) to improve the adsorption capacity. MWCNTS were loaded to enhance the water stability of the material. The structure, surface morphology, and pore size distribution of the composites were characterized using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and specific surface area and pore structure measurements. The CO2/CH4 selective adsorption performance was studied via breakthrough experiments using a self-made adsorption device. The CO2 adsorption capacity of Cu-BTC increased due to the addition of NH2-BDC, with 35%NH2-Cu-BTC exhibiting the best CO2 adsorption property, i.e., a CO2 adsorption capacity of 1.82 mmol/g and a CO2/CH4 sepa... [more]

One of the main trends in the development of the modern electronics industry is the miniaturization of electronic devices and components. Miniature electronic devices require compact cooling systems that can dissipate large amounts of heat in a small space. Researchers are exploring ways to improve the design of the heat sink of the cooling system in such a way that it increases the heat flow while at the same time reducing the size of the heat sink. Researchers have previously proposed different designs for heat sinks with altered fin shapes, perforations, and configurations. However, this approach to optimizing the design of the heat sink results in an increase in the labor intensity of its production. Our goal is to optimize the heat sink design to reduce its size, reduce metal consumption, and increase heat flow. This goal is achieved by changing the number of fins and the distance between them. In this case, there is no significant difference in the geometry of a conventional plat... [more]

New energy storage methods based on electrochemistry can not only participate in peak shaving of the power grid but also provide inertia and emergency power support. It is necessary to analyze the planning problem of energy storage from multiple application scenarios, such as peak shaving and emergency frequency regulation. This article proposes an energy storage capacity configuration planning method that considers both peak shaving and emergency frequency regulation scenarios. A frequency response model based on emergency frequency regulation combined with low-frequency load shedding is established, taking into account the frequency safety constraints of the system and the principle of idle time reuse, to establish a bi-level programming model. In the upper-level model, the optimization objective is to minimize the annual operating cost of the system during the planning period, combined with the constraints of power grid operation to plan the energy storage capacity. The lower-level... [more]

The utilization of bioactive compounds from fresh produce waste, which is gaining attention in the agri-food and cosmetics industries, focuses on employing green extraction over conventional extraction methods. This emerging field addresses environmental concerns about food waste and the uses of bioactive phytochemicals for skin health. Modern green extraction methods aim to minimize the energy-intensive process and the use of harmful solvents. These techniques include ultrasound, microwave, and supercritical fluid extraction, pulsed electric field extraction, pressurized liquid extraction, and subcritical water extraction methods, which provide high efficacy in recovering bioactive phytochemicals from vegetable and root crops. The phytochemicals, such as carotenoids, polyphenols, glucosinolates, and betalains of fresh produce waste, exhibit various therapeutic properties for applications in skin health. These dietary antioxidants help to neutralize free radicals generated by UV radiat... [more]

The Helmholtz method is developed to predict the self-excited thermoacoustic instabilities in a gas turbine combustor, combining flame describing functions, the measured damping rates under the firing condition, and the non-uniform spatial distributions of the physical parameters. The impact of the hydrodynamic and geometrical parameters on the thermoacoustic instabilities is investigated. The measured damping rates show lower values under a hot condition compared with those in a cold state. The experimental results indicate that the relative errors of the predicted eigenfrequencies and the velocity fluctuation levels are below 10%. The pressure amplitude decreases and the phase increases in the axial direction, indicating a typical 1/4-wavelengh mode. At a higher equivalence ratio, the mode shape in the axial direction becomes steeper due to the elevated fluctuation amplitude at the pressure antinode after enhancing the thermal power. When the air flow rate increases, the discrepancie... [more]

The paper presents the application of MTM, RAV and ZAK methods in the determination of working methods and time norms for the technological process of sewing. The technological operation of sewing the back sleeve seam on a men’s jacket is used for the study. The paper presents the designed workplace in a real production process. In addition, the appropriate working method and the time norm are determined using the MTM (Method Time Measurement), RAV (determination of sewing time for straight seams) and ZAK (determination of sewing time for curved seams) methods. The aim of the study was to combine the methods for determining different types of time (manual, machine-hand and machine) for performing technological operations and precisely calculate the time norms. For the described methods of determining the production time, computer programs were developed that speed up the calculation of the time norm. If the working method is defined in advance and the characteristics of the sewing mach... [more]

Blowout is one of the most serious safety threats in deepwater drilling. Considering the characteristics of gas invasion in complex formations, gas migration and distribution, and dynamic changes in temperature inside a wellbore, a deepwater well-closing pressure determination method considering thermal-fluid-solid coupling was proposed. The model was verified using actual data, and the average error in the increase in casing pressure during the closing process was found to be 5.42%. The shut-in pressure of oil and gas wells under a transient shut-in process was analyzed. The results showed that the fluid thermal expansion caused by temperature recovery had a significant impact on the change in wellhead backpressure after well closure. Furthermore, the time required for the wellbore pressure to recover to the formation pressure varies nonlinearly with factors such as geothermal gradients, pit gains, bottom-hole pressure, and gas production indices. A pressure calculation chart was deve... [more]

This study addresses the urgent need for effective water treatment methods by synthesizing and characterizing activated bentonite clay (ABC) adsorbents to remove methylene blue (MB) from aqueous solutions efficiently. Conventional adsorbents often exhibit limitations in efficiency and regeneration capabilities, necessitating novel approaches to water treatment. The primary objective is synthesizing and characterizing high-quality ABC adsorbents capable of effectively removing MB. The activation process was optimized, and adsorbent performance was evaluated regarding MB removal efficiency and regeneration potential. Various activation dos-ages were investigated, and comprehensive physicochemical characterization was performed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), BET (Brunauer−Emmett−Teller) analysis, X-ray fluorescence (XRF), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The synthesized adsorbents demonstrated excepti... [more]

Industrial process heating furnace operations consume considerable energy in the U.S. manufacturing sector, making it crucial to identify energy efficient strategies due to the growing need to minimize energy usage and emissions. It is important to identify the potential impact of these factors to enable process engineers to operate process heating systems at the maximum possible efficiency. This study examines and identifies the key impact factors that influence the efficiency of process heating systems using MEASUR (v1.4.0), the DOE software tools such as the insulation effectiveness, the burner stoichiometry, cooling medium, thermal storage, and atmospheric gases. Data from a two-fuel-fired heat treatment furnace and an electric arc furnace (EAF) for steelmaking were employed to establish the baseline heat balance models in MEASUR. The fractional factorial design experiment was developed with two-level parameter values and energy efficiency strategies for the heat input into industr... [more]

Elevated temperatures at the transformer bushing cylinder head can precipitate failures, leading to significant power outages. In response, this study introduces a reversible temperature-indicating patch for the nuanced detection of thermal anomalies in the transformer bushing’s cylinder head. The patch, crafted through a melting process, utilizes a reversible discoloration material and is developed in two variants via an adsorption substrate method. Comprehensive evaluations of the patches’ color-changing characteristics, alongside their electrical and hydrophobic properties, were conducted using an automatic contact angle measuring instrument and an AC flashover test platform. The findings reveal that the temperature-indicating patch exhibits a discernible color transition within the range of 49~55 °C, with a color reversion temperature span of 45~55 °C, denoting marked sensitivity and robust reversibility. Additionally, it was observed that prolonged thermal aging correlates with a... [more]

Coal dust particles adhering to a camera lens reduce its light transmittance, which deteriorates the performance of the camera and may lead to serious problems with mining equipment that requires visual ability. Aiming at improving coal dust removal and cleaning technologies, the adhesion behavior of coal dust with fused silica is studied here. Experiments were conducted from microscopic and statistical points of view. The adhesion force between a single coal dust particle and fused silica is tested using atomic force microscopy (AFM), and the number and size distribution of large amounts of coal dust particles on fused silica are tested using a home-made adhesion experimental platform and image processing method. The results show that the adhesion force increases at high relative humidity (RH); it is dominated by van der Waals forces at low RH and capillary forces at high RH. The fused silica glass surface is predominantly covered by small-sized coal dust particles, and the total numb... [more]

Wastewater treatment is now required because of the problems caused by water constraints. Wastewater is anaerobically digested to produce biogas, which can be used as a source of energy for things like lighting and heating. The upflow anaerobic sludge blanket (UASB) reactor has been recognized as an important wastewater treatment technology among anaerobic treatment methods. Although their treated effluent typically does not meet most discharge criteria, UASB reactors are generally stated to have a chemical oxygen demand (COD) reduction ranging from 60 to 90% for most types of wastewater. In comparison to traditional anaerobic procedures, anaerobic municipal wastewater treatment using membranes can produce higher effluent quality in terms of COD, suspended solids (SSs) and pathogen counts, as well as a steady treatment performance to fulfill strict discharge regulations. The objective of this review was to perform a literature review on parameters to consider when selecting a membrane... [more]

Due to their high porosity and permeability characteristics, reservoirs of loose sandstone have great development potential. Under weak dynamic conditions, the vertical migration and mass exchange of oil−water two-phase fluids in loose sandstone reservoirs occur very easily. The phenomenon of vertical seepage flow equilibrium has a significant impact on the distribution of oil−water two-phase fluids in the reservoir. However, existing mainstream numerical simulators cannot accurately describe the phenomenon of vertical migration of oil−water two-phase fluids under weak dynamic conditions. In this study, using 3D printing technology, multiple transparent rock core holders were constructed to conduct experiments on the vertical seepage flow equilibrium time of different viscosities and contents of crude oil under different permeabilities of rock cores. Through the analysis and regression of experimental results, a predictive formula for the vertical seepage flow equilibrium time of loose... [more]

Vertical axis wind turbines (VAWTs) are gaining increasing significance in the realm of renewable energy. One notable advantage they possess is their ability to operate efficiently in diverse wind conditions, including low-speed and turbulent winds, which are often prevalent in urban areas. In this study, dimples and pitch angles into the rotor blades are used to enhance the aerodynamic performance of a straight-bladed Darrieus turbine. To simulate the turbine’s rotation under transient conditions, computational fluid dynamics calculations are conducted in a two-dimensional setting. The unsteady Navier−Stokes equations are solved, and the k-ω SST turbulence model is employed to represent turbulent flow. The results of the simulation demonstrate that the application of a circular dimple on the pressure side of the blades, positioned at 0.25 of the chord length with a diameter of 0.08 chord length, leads to a 5.18% increase in the power coefficient at λ = 2.7, in comparison to a turbine... [more]