Compared to traditional fixed source flue gas capture technologies, CO₂ direct air capture (DAC) has advantages such as flexible positioning and wide application. However, due to the extremely low concentration of CO₂ in the atmosphere (only around 0.04%), the high energy consumption of DAC has become the primary obstacle to its commercialization. Focusing on the energy consumption issue of adsorption based DAC, theoretical analysis and case studies have been conducted. The ideal minimum work for CO₂ separation of DAC was calculated to be 19.64 kJ·mol^-1 (temperature of 298.15 K, capture ratio of 50%, purity of 95%), which is 3.5 times that of flue gas capture technology under the same conditions. At a regeneration temperature of 393 K, the second law separation efficiency of temperature vacuum swing adsorption cycle (TVSA) is 22.75%. The processes of adsorption, evacuation, regeneration, condensation, compression, etc., are mainly driven by mechanical and thermal energy. The mechanical energy during the evacuation process accounts for only about 3% of the total energy consumption. The heat energy during the condensation process can be recovered through a regenerative cycle. The mechanical energy of the compression process is included in DAC in some studies and is determined by the target pressure. The flow mechanical energy during the adsorption process accounts for over 90% of the mechanical energy consumption, which is 5.43 GJ·t^-1 when using a conventional reactor. Structured reactors can reduce pressure drop to 1/1000, and reducing flow rate can also improve resistance and enhance capture ratio. The thermal energy during the regeneration process accounts for the main part of DAC energy consumption, about 50%—80%. The regeneration temperature, the mass ratio of the reactor to the adsorbent, and the strength of the adsorbent's adsorption of H₂O can all cause a multiple change in the heat consumption. Based on the analysis of the process energy consumption, recommendations for optimizing the energy consumption of adsorption DAC in terms of reactor design, circulation mode and operating parameters, natural environment and energy sources are given.

Liquid-liquid heterogeneous reactions are widely involved in various fields of the petrochemical and fine chemical industries. Owing to the difference in the physical and chemical properties of the liquid-liquid phase and the existence of the phase interface, the liquid-liquid heterogeneous reaction process is usually affected by both intrinsic reaction kinetics and the transfer process. Therefore, enhancing the liquid-liquid heterogeneous reaction transfer process and matching it with the reaction kinetics to achieve efficient utilization of raw materials and energy has always been one of the hot topics of researchers. Focusing on the intensifying mechanism and application of the liquid-liquid heterogeneous reactions and transfer processes, this paper takes typical heterogeneous reactions such as nitrification and dehydrochlorination reactions as examples, combined with the basic characteristics of reaction kinetics, thermodynamics and transfer processes, reviews the mechanism of the effect of the transfer-reaction process coupling on reaction selectivity and spatio-temporal yield, and describes the challenges faced by industrial applications and the solutions by process intensification. Furthermore, the application potential of liquid-liquid heterogeneous reaction process intensification is prospected from the perspective of matching the reaction and transfer processes.

Spray cooling has become an effective way to solve the heat dissipation problem of high-power electronic components due to its advantages of strong heat dissipation capacity, low working fluid consumption, and low contact thermal resistance. By summarizing the heat transfer enhancement mechanism of spray cooling, the challenges and bottlenecks currently faced by spray cooling technology, as well as the main development direction in the future, are pointed out. Firstly, the heat transfer mechanism of spray cooling is summarized. Compared with other cooling technologies, spray cooling with complicated heat transfer mechanism is more conducive to the heat dissipation of high-power electronic devices. Secondly, the latest experimental research progress of various strengthening means of spray cooling is introduced in detail, focusing on the working medium modification, surface treatment, spray parameters optimization and external physical field application. Then, the research status of novel electrospray cooling with a high-voltage electric field is introduced. Finally, the scientific challenges and technical bottlenecks of spray cooling technology in theoretical research and industrial application as well as the future direction of efforts are discussed.

Lithium metal batteries are widely recognized as one of the most promising technical pathways for driving innovation in high-energy-density battery technology due to their extremely high theoretical energy density. In response to different electrolyte systems (liquid/solid), the different stress states and material characteristics within lithium metal batteries lead to distinct core challenges. In liquid electrolytes, the uncontrollable growth of lithium dendrites needs to be focused on, while in solid systems, the contact of solid-solid interfaces needs to be focused on first. This article systematically examines how external pressure and internal stress in lithium metal batteries with different electrolyte systems work together on the battery structure, thereby affecting its electrochemical performance and behavior. Through in-depth analysis, it reveals the key role of mechanical factors in promoting the improvement of battery performance. Finally, this article provides a comprehensive review and evaluation of the mechanical fixtures widely used in the current field of lithium metal battery research, summarizing the specific applications and effects of these tools in experimental research, aiming to provide strong technical support and theoretical guidance for the continuous development and commercialization process of lithium metal battery technology.

Phase change energy storage technology has broad application prospects in fields such as promoting the consumption of volatile renewable energy and achieving low-cost energy supply by utilizing the peak-valley price difference. Due to the low thermal conductivity of most solid-liquid phase change materials and the weak convection effect in phase change energy storage systems, the heat storage/release rates of phase change energy storage systems are slow. Therefore, the development of highly efficient solid-liquid phase change heat transfer enhancement technologies has become a research hotspot in this field. Most of the existing studies enhance solid-liquid phase change heat transfer through passive methods such as the regulation of the thermophysical properties of phase change materials and the optimization of heat exchange structures, while there are relatively few studies on active solid-liquid phase change heat transfer enhancement technologies based on external field disturbances. For this reason, this paper systematically reviews the latest progress in the research on active heat transfer enhancement technologies for solid-liquid phase change under the conditions of external magnetic fields, electric fields, acoustic fields, and multi-field coupling at home and abroad, analyzes the principles, key control parameters, and application prospects of active enhancement of solid-liquid phase change heat transfer by external fields, and provides a good scientific reference and engineering guidance for the development of active heat transfer enhancement technologies for solid-liquid phase change based on external field disturbances.

Alkaline membrane fuel cells (AMFCs) have attracted much attention due to the low cost and faster oxygen reduction kinetics. Especially, in the membrane electrode assembly (MEA) of AMFCs, the durability of alkaline polyelectrolytes (as the ion conducting media and catalytic layer binders) in high alkaline environment is one of important factors ensuring the long-term stable operation of AMFCs. This article reviews the research on the durability of alkaline polyelectrolytes in recent years and their applications in AMFCs. The mechanisms by which different main chains and cationic groups affect the durability of alkaline polyelectrolytes are emphatically summarized. It is hoped to provide reference for the molecular structure rational design of alkaline polyelectrolytes.

As an aromatic polymer with abundant reserves in nature, lignin is rich in hydroxyl, carboxyl, ether and other functional groups in its structure. These functional groups can make lignin through simple and mild chemical activation to prepare porous carbon materials. Such carbon materials usually have large specific surface area and porous structure, which is conducive to sulfur loading and electrolyte penetration. Lithium-sulfur (Li-S) batteries show high theoretical specific energy, environmental friendliness, low cost and other advantages, so it is regarded as one of the most potential alternative batteries beyond the energy density limit of lithium-ion batteries. In this paper, the preparation methods of lignin-based polyporous carbon and its application in lithium-sulfur batteries were reviewed. The effects of different characteristics of lignin-based polyporous carbon in structure, composition and design on battery performance were discussed. The future application prospects of lignin-based carbon materials were also prospected.

For the extraction-concentration and tail gas washing fluorine release process of wet phosphoric acid, the gas-liquid distribution ratio of fluorine element under thermodynamic equilibrium of H₂SiF₆-H₂O and H₂SiF₆-H₃PO₄-H₂SO₄-H₂O systems was established, and the model prediction error was within 20%. Based on the thermodynamic analysis, reducing the tail gas washing temperature can increase the mass transfer driving force, improve the mass transfer rate of fluorine absorption and produce high concentration fluorosilicic acid solution, but the condensate water increases, which increases the water balance pressure of the system. A 75000 t P₂O₅/a WPA tail gas emission reduction and resource utilization project was designed and implemented. The unit operation of concentrating fluorosilicic acid by flash evaporation without pump was connected in series in the fluorine absorption circulating circuit. The low temperature and high concentration fluorosilicic acid is used to absorb and cool the tail gas below 323 K to make the fluorine-containing tail gas supersaturate and condense, which not only enhances absorption of the tail gas fluoride, but also avoids the loss of fluidity due to the agglomeration of silica particles. The results show that the fluorine content in tail gas is ≤2 mg/m³, the recovery of fluorine in tail gas is ≥99%, the total emission reduction of tail gas is more than 20%, and the H₂SiF₆ is ≥18%(mass) in the fluorosilicic acid product. An engineering example of high efficiently recycle of fluorine contained in tail gas from wet-process phosphoric acid plant is provided.

To achieve accurate flow measurement of CO₂ in pipeline transportation under carbon capture, utilization, and storage conditions, during which liquid phase is the primary phase in the gas-liquid two-phase CO₂, a flow measurement method using the differential pressure ratio from the contraction and expansion sections of a Venturi tube is proposed for gas-liquid two-phase CO₂ flow based on the over-reading model. Through theoretical analysis and experimental verification, the corresponding law between the differential pressure ratio and the Lockhart-Martinelli (L-M) parameter and the virtual height of the liquid phase is revealed. A model for the iterative calculation of the liquid-gas mass flow ratio is proposed, which can address issues in the classical models and enable accurate liquid and gas phase flow measurement of gas-liquid two-phase CO₂. Under conditions of the pressure in pipeline ranging from 4.9 MPa to 5.2 MPa, temperature changing from 14℃ to 17℃, and liquid-gas mass flow ratio between 8.78 and 28.85, the relative error of total mass flow rate is within ±2.3%, the relative error of liquid phase mass flow rate is within ±2.2% and the relative error of gas phase mass flow rate is within ±6.3%. The results prove that the Venturi flowmeter based on dual differential pressure model provides simple, reliable and economic solution for the flow measurement of gas-liquid two-phase CO₂.

The bubble collision phenomenon plays a crucial role in multiphase dispersion process, affecting the bubble size distribution and flow field structure. The bubble collision process includes two sub-processes of bubble approaching each other and liquid film drainage thinning. However, the existing models have limitations in predicting bubble collision, especially the rebound phenomenon, mainly due to the neglect of surface deformation outside the liquid film region. The surface deformation caused by collision may cause part of the system kinetic energy to be converted into surface energy, which accelerates the consumption of system kinetic energy to a certain extent. By introducing the restoring force caused by surface deformation into the force equilibrium equation for bubble approaching process, an improved model coupling the approaching-thinning process is developed. The results show that in comparison with the traditional model, the improved model has higher accuracy in predicting bubble collision. As the bubble collision speed increases, the restoring force on the bubble surface due to surface deformation is greater, the deformation may be more obvious.

In order to explore the coupled flow and heat transfer characteristics with orthohydrogen and parahydrogen conversion in the hydrogen liquefaction process based on helium expansion refrigeration, the orthohydrogen and parahydrogen conversion reaction with flow and heat transfer performance of hydrogen gas in a four-flow plate-fin heat exchanger were studied by using CFD numerical simulation method. The effects of catalyst particle size and porosity, hydrogen inlet Re, low-pressure helium to hydrogen mass flow ratio (m_r) on flow and heat transfer performance and outlet volume fraction of para-hydrogen were analyzed. The research results show that: when the porosity increases from 0.3 to 0.7, the heat transfer enhancement factor TEF can be increased by 71.59% at most; the particle size increases from 390 μm to 790 μm, and the TEF can be increased by a maximum of 37.05%; the use of larger porosity and catalyst particle size is more conducive to improving the comprehensive heat transfer performance of the hydrogen channel. When the hydrogen inlet Re decreases from 1500 to 500, the TEF can be increased by up to 147.96%. The channel heat transfer performance is better under low Re operating conditions. When the mass flow ratio of low-pressure helium gas to hydrogen gas m_r = 6, the heat transfer performance of hydrogen gas in the finned channel reaches its optimal state through the coupling of orthohydrogen and parahydrogen conversion with flow and heat transfer. The research results of this article can provide theoretical guidance for the hydrogen liquefaction system of large-scale helium expansion refrigeration.

Rotor swirling flow is one of the effective ways to dynamically enhance nanofluid heat collection. This study analyzed the action of swirling flow of two blade rotors in a closed solar collector tube through numerical simulation, and the effects of irradiation intensity and nanofluid concentration on the heat collection performance of water-based carbon black nanofluid under the action of swirling flow. The results show that the swirl effect can significantly improve the heat collection performance of nanofluids, and the temperature rise can be increased by 33.81% under the action of a single rotor alone. Within the range of rotor number research (0, 1, 2, 4), the disturbance flipping degree of the nanofluid increases with the increase of rotor number, and the heat collection performance and temperature uniformity are significantly improved. Under the action of swirling flow, within the range of irradiation intensity research (500—1500 W·m^-2), the temperature rise of water-based carbon black nanofluid is linearly positively correlated with irradiation intensity. For every 100 W·m^-2 increase in irradiation intensity, the temperature rise inside the collector tube can be increased by 2.7℃. Within the range of nanofluid concentration research [0%—0.010% (mass)], the amount of radiation absorbed per unit volume of nanofluid increases with increasing concentration, and the change in concentration will not affect the uniformity of the temperature distribution in the heat collector. This study simulated the photothermal conversion performance of nanofluids under the action of two blade rotors, providing a new direction for dynamic solar energy collection.

In order to cope with the increasing heat dissipation demand of micro-electronic devices, this paper optimizes the flow channel layout of the minichannel heat sink, avoids some flow dead zones, reduces unnecessary flow branches, and obtains an interwoven block coupled honeycomb minichannel with better heat transfer performance. The flow and heat transfer characteristics of nanofluids in minichannels were studied by numerical simulation. The results indicated that the average temperature of the improved heat sink wall is reduced by 2.16 K. Compared to water, the Nusselt number of the nanofluids with the mass fraction of 0.5% as the cooling medium is increased by 13.1%, the thermal resistance is reduced by 12.4%, and the comprehensive evaluation coefficient PEC of the whole minichannel under the best working condition reaches 1.211.

A new type of aluminum, fanless, built-in heat storage material direct condensing radiant panel heat exchanger (AHE) is proposed, which can be combined with an air source heat pump system for indoor winter heating in buildings. Based on the heat transfer mechanism of the heat storage type direct condensation radiant panel and considering the influence of refrigerant flow on heat transfer performance, a flow heat transfer mathematical model suitable for AHE was established, and the accuracy of the model was verified through experiments. The results showed that the numerical simulation results of heat dissipation, pressure drop, and heat exchanger surface temperature had an average deviation of less than 5% from the experimental values. Numerical simulations were conducted on the thermal performance of AHE under 168 working conditions, and the results showed that increasing the condensation temperature and refrigerant flow rate helps to improve the heat transfer intensity, while increasing the condensation temperature is beneficial for reducing flow losses. In 168 working conditions, the average temperature difference between AHE refrigerant and surface temperature was 9.7℃, and the maximum temperature difference between adjacent structural layers of AHE was 6.3℃ between the copper tube and the water layer. Finally, a heat dissipation characteristic formula suitable for AHE thermal performance prediction was proposed, providing a technical basis for performance analysis and optimization of radiant heating panel systems.

The reciprocating spiral inserted in the tube has good heat transfer enhancement and scale inhibition performance. The effects of three spiral pitches on the total heat transfer coefficient, scale thermal resistance and scale layer thickness were studied through an experimental system. Combined with the microscopic characterization of crystallized scale under complex flow field conditions, the reasons for the scale inhibition and removal of the inserted reciprocating spiral were deeply analyzed. The results show that: within the experimental conditions, with the increase of the solution flow rate in the tube, when the reciprocating displacement is one pitch, the total heat transfer coefficient stability value is only 3% lower than that of the non-fouling, the maximum reduction of the stability value of the fouling thermal resistance of the tube is 84%, and the average thickness of the fouling is less than 0.1 mm, and the fouling microscopic appearance appears as hexagonal crystals and small dense crystals, and the fouling layer can't completely cover the heat transfer surface. At this time, the reciprocating spiral has continuous on-line scale inhibition performance, and the shear force of the spiral on the dirt layer is greater than the maximum shear force it can withstand, which is the fundamental reason for the better scale inhibition performance.

Rotating packed bed (RPB) has great potential in enhancing reaction and process mass transfer, but the study of its complex internal flow field is still a challenge. Understanding fluid motion is crucial for comprehending the mass transfer process. Operating the RPB in a highly sealed condition limits the ability to capture the details of the flow field inside. Computational fluid dynamics (CFD) simulations offer an effective flow field analysis method. This study proposes using a CFD model to investigate the gas-phase flow within each cavity region of the RPB. A porous media model simulates the packing region, and centrifugal rotation is incorporated into the drag calculation. Furthermore, a drag coefficient correction equation that includes the rotor speed is proposed for the first time. The experimental study covers the steady-state operational process under different rotor speeds and gas flow rates. The dry pressure drop of the RPB is obtained through iterative calculations of the drag-corrected CFD model, which serves as a key performance indicator. The average deviation between the converged pressure drop values and the experimental results is 4.71%, with a maximum deviation of 12.24%.The results of the CFD simulation are verified. Based on the validated theoretical model, further rotor performance studies incorporated a compound inverse rotor (CIR) structure with the inner rotor set to 1500 r/min. The findings indicated that the mean turbulent kinetic energy at the RPB packing increased by up to 5.77 times, thereby substantiating the potential for structural optimization in augmenting the mass transfer and treatment efficacy of the RPB. This provides a theoretical foundation for comprehensive research and development of environmental protection equipment for the RPB-enhanced chemical industry.

An experimental study was conducted on the flow and heat transfer characteristics of supercritical CO₂ in a 1.6 mm × 1.6 mm horizontal square tube under heated conditions. The experimental parameters were: system pressure between 7.4 to 8.4 MPa (relative pressure p/p_cr = 1.003—1.138), mass flux ranging from 500 to 1500 kg/(m²·s), and heat flux from 100 to 300 kW/m². The influence of thermal parameters, buoyancy and thermal acceleration effect on heat transfer characteristics in square pipes is analyzed. According to the distribution characteristics of heat transfer curves, supercritical CO₂ flow heat transfer is divided into three regions: liquid-like, two-phase, and gas-like. The experimental results showed that increasing the mass flow rate and reducing the heat flux effectively enhanced the convective heat transfer coefficient, achieving improved heat transfer. In the square microchannel, buoyancy strengthened heat transfer at the bottom wall, while the top wall experienced weaker heat transfer. The effect of thermal acceleration on convective heat transfer in this experiment was found to be negligible. A new dimensionless heat flux, q⁺, was introduced based on mass flux, wall, and mainstream temperatures, and a new heat transfer correlation was derived using q⁺ and other influencing factors, with a prediction error range of +20% to -20%.

Advanced adiabatic compressed air energy storage (AA-CAES) is a promising technology for solving the problem of renewable energy power consumption. To improve the efficiency of AA-CAES, it is proposed to use direct contact heat exchangers as reheater to make full use of system compression heat. In this paper, the pressurized humidifier experimental system and air-water system is used to study the direct contact heat transfer process. An experimental setup with the foam ceramic corrugated packing was tested under pressurized conditions. The liquid flooding characteristics of the packing were analyzed. The effects of the operating pressure, the water-gas ratio, the inlet water temperature and the inlet air specific enthalpy on the volume mass transfer coefficient and the effectiveness were investigated. The results show that the volume mass transfer coefficient of the packing increases with the increasing water-gas ratio and decreases with the increasing inlet water temperature, while the efficiency decreases with the increase of the water-gas ratio and increases with the increase of the inlet water temperature. The influence of the inlet air specific enthalpy on the direct contact heat transfer process is relatively small. For AA-CAES, when designing direct contact heat exchange processes, the water-gas ratio is proposed to be taken as 1.0—1.2, and the operating pressure is proposed to be taken as 0.3—0.4 MPa.

Compared with pure SF₆ gas, the decomposition products produced by the discharge failure of SF₆/N₂ gas mixture GIS equipment are more complex, which increases the difficulty of purifying the SF₆/N₂ gas mixture. Therefore, it is of great significance to study the adsorption and purification methods of decomposition products of SF₆/N₂ gas mixture. In this paper, an experimental platform for adsorption of decomposition products of corona discharge was designed and built, and the SF₆/N₂ gas mixture and its decomposition products were quantitatively analyzed. In the adsorption platform, UIO-66 was used to conduct adsorption experiments on SF₆/N₂ gas mixture and its decomposition products, and the adsorption capacity of UIO-66 was analyzed. Based on the theoretical basis of quantum chemistry and classical mechanics, the bonding space and geometric parameters between atoms are carefully optimized to ensure that the simulated structure and gas molecules are close to the real shape. Based on molecular dynamics theory, UIO-66 before modification and three kinds of modified organometallic frameworks (UIO-66-12Ti, UIO-66-24Ti and UIO-66-36Ti) were analyzed, and the diffusion behavior of SF₆/N₂ gas mixture and its decomposition products in four kinds of organometallic frameworks was simulated at 300 K and 100 kPa. The effects of adsorption heat and pressure on the adsorption capacity of four organometallic frameworks were further analyzed by Monte Carlo simulation. The simulation results are verified by experiments. The study reveals that unmodified UIO-66 achieves adsorption efficiencies over 67% for H₂S, SO₂, SO₂F₂, and SOF₂, but less than 5% for N₂O and CF₄. After modification, the three metal-organic frameworks show a 41.02% average increase in adsorption capacity for N₂O, H₂S, SO₂, SO₂F₂, SOF₂, and CF₄, and the adsorption capacity of SF₆ was almost unchanged, which was beneficial to separation and recovery, with UIO-66-24Ti leading in N₂O and CF₄ adsorption enhancements at 86.55% and 67.06%, respectively. The experimental results show that the adsorption performance of UIO-66-50%Ti modified by doping Ti is obviously improved compared with that of pure UIO-66. Therefore, the modified organometallic architecture is favorable for the adsorption and purification of decomposition products in SF₆/N₂ gas mixture, which provides a theoretical basis for the development of adsorbents suitable for decomposition products in SF₆/N₂ gas mixture.

Papermaking wastewater treatment process is susceptible to uncertain factors such as production process conditions switching and raw material heterogeneity. In the context of the coordinated development of pollution reduction and carbon reduction in the industry, how to ensure the discharge of sewage treatment in the water quality standard, and achieve synchronous reduction of treatment costs, energy consumption, and greenhouse gas emissions is an important issue restricting the development of the industry. In this paper, a multi-objective wastewater optimization method based on Kriging method and high dimensional model representation (HDMR) is proposed for the dynamic uncertainty of papermaking wastewater treatment. In this study, benchmark simulation model No. 1 (BSM1) was used to simulate the biochemical and precipitation processes of papermaking wastewater treatment process. Based on biochemical metabolism mechanism and data fusion, a Kriging-HDMR proxy model for real-time solving of greenhouse gas emissions in wastewater treatment process was established. By integrating the agent model into reinforcement learning, a multi-agent system based on“solving-decision-observation” for dynamic optimization of the wastewater treatment process was established, and a coordinated multi-objective optimization model for pollution reduction and carbon reduction was obtained. The study scenario results show that compared with the open-loop system, the dynamic optimization system can reduce operating cost by 4.10%, energy consumption by 22.10%, and greenhouse gas emissions by 10.30%, and can obtain and maintain an effective multi-objective dynamic optimization control strategy.

In practical industrial production, the time lags and sampling rate differences among process variables can deteriorate the modeling quality, rendering many soft sensing models inapplicable. Therefore, a soft sensing modeling approach based on time-aware temporal pattern attention (TTPA) mechanism and long short-term memory network is proposed. In this study, we first reconstruct the data corresponding to high and low sampling rates into short-term and long-term information, respectively. A time-aware module is utilized to decompose the input information while considering the characteristics of time intervals. To address the issue of low proportion of quality-related information, a non-increasing heuristic decay function is designed to weight the short-term information. By combining these weighted components, we derive an integrated feature set that encapsulates both short-term and long-term information, thereby mitigating the impact of data loss resulting from multiple sampling rates. Secondly, a feature optimization module is introduced to achieve two-dimensional filtering of features, and the time lag information in the multivariate time series is analyzed across time steps to obtain more effective quality-related features. Finally, a soft sensing model based on TTPA-based long short-term memory network is established. The effectiveness and superiority of the proposed model were verified through the application simulation of IndPensim process and debutanizer process.

Online detection of rare earth element content is a key link in rare earth industrial process control. Aiming at the problem that the existing soft measurement model of single color feature is not ideal, a soft measurement method of rare earth element content based on transfer learning residual attention convolutional network is proposed. Initially, prominent features such as color and texture are extracted from images of rare earth solutions. Additionally, latent convolutional features along with other critical elements are utilized as inputs to the soft sensing model. Subsequently, we design a one-dimensional CNN featuring multiple residual attention blocks to accommodate the one-dimensional nature of the rare earth solution image features. An attention mechanism is integrated, enabling the model to self-adjust the weighting of features based on their contribution, thereby enhancing model accuracy. The inclusion of a residual structure addresses issues related to vanishing or exploding gradients effectively. To make full use of solution image data in production process and reduce sample collection, a transfer learning strategy is employed. This strategy leverages data and knowledge accumulated from a source task, the maximum mean difference is used to measure the difference of feature distribution between the source domain and the target domain data, then the migration level and parameters are determined, and substantially improving the training outcomes of the target network. Finally, based on the laboratory image acquisition device and combined with field data, the simulation validation was conducted, and the results demonstrate the effectiveness of the proposed method.

This paper proposes an AdaBoost strategy based on training quality and a multimodal neural network machine learning method based on Alopex evolutionary algorithm for the dynamic process of ultrafiltration performance in sewage reverse osmosis water pretreatment. Firstly, this paper constructs a class of generalized Bayesian inference probability indicators suitable for arbitrary distributions to classify multimodal states such as filtration and backwashing in ultrafiltration reverse osmosis wastewater treatment processes. Then, a neural network algorithm based on Alopex evolutionary algorithm and distribution-based AdaBoost ensemble strategy is used to model each modal process separately. Finally, the constructed generalized Bayesian inference-based probability indicators for each modality are used to integrate multiple models of the multimodal process. In order to verify the effectiveness of the method proposed in this paper, the method was applied to a two-year dataset collected from a community in the United States. The proposed method has good predictive performance for membrane resistance and backwash efficiency, and can effectively predict expected water quality changes.

Accurate prediction of the fouling state of the heat exchanger can timely understand the degree of fouling, so as to implement targeted cleaning, which is of great significance to improving the economic use and production safety of the heat exchanger. The model integration of convolutional neural network (CNN) and long short-term memory network (LSTM) was used to predict the heat exchanger fouling factor. A large number of historical data of heat exchanger are used to train the CNN-LSTM model, and excellent prediction results are obtained. Compared with the single CNN and LSTM models and the multi-layer perceptron neural network (MLPNN) models in the literature, the CNN-LSTM model is more accurate and more stable. In the case shown, the coefficient of determination (R²) is 0.98167, and the average absolute percentage error (MAPE) is 3.199×10^-3. The establishment of the model not only provides a theoretical basis for solving the scale problem of the heat exchanger, but also provides a more scientific and accurate basis for the safe operation and maintenance strategy of the heat exchanger. It helps to improve the economy and production safety of the entire heat exchange section.

Allam cycle is a highly regenerative oxygen combustion power cycle with CO₂ as the working fluid, which is considered to be promising for zero-carbon power generation from fossil fuels. In order to accurately assess the thermodynamic and economic performance of the Allam cycle, a novel improved regenerator layout consisting of four heat exchangers is proposed in this paper. The cycle system is modeled in detail, and then detailed thermodynamic and economic analyses are carried out for the improved Allam cycle. The influences of main operating and economic parameters on the thermodynamic and economic performance are analyzed, and finally a dual-objective optimization is carried out with the objectives of thermal efficiency (η_tot) and the levelized cost of electricity (LCOE). The thermal efficiency and LCOE are 51.9% and 107.5 USD/MWh at a combustion temperature of 1150℃ and turbine inlet/out pressures of 30/3.4 MPa. Regenerators 1 and 3 have relatively high investment costs, resulting in the second highest total cost rate for the entire regenerator unit. The results of parameter analysis reveal that the combustion temperature has a considerable effect on η_tot and LCOE. The maximum cycle pressure and the turbine exhaust pressure have similar effects and mainly affect the LCOE of the cycle. The capacity factor has the highest influence on the LCOE, followed by the interest rate. The LCOE is reduced linearly with the decrease in the price of natural gas. The LCOE decreases by approximately 4 USD/MWh with every 10% decrease in the price of natural gas. η_tot and LCOE cannot reach the optimal value at the same time. Within the given range, the optimal η_tot and LCOE are 52.3% and 95.7 USD/MWh respectively.

Aiming at the problem that the key parameters of complex chemical process are difficult to be accurately soft-measured due to the non-stationarity and event-driven characteristics, an event-driven deep belief network (EDDBN) soft-sensing model is proposed. First, the operating data of chemical process is obtained and a deep belief network (DBN) model is built. The DBN model is trained in a data-driven way to obtain a soft sensor model based on DBN. Second, some events are defined based on the training-error characteristics of the DBN model. The learning step of parameters in DBN model will be accelerated when the positive events occur, and skip the current data sample and directly go to the next data sample. This event-driven selective learning strategy not only efficiently optimizes the training process of soft-sensing model, but also reduces the computational complexity. Meanwhile, this paper analyzes the boundedness of difference between performance potentials from two consecutive events by construct Markov chain-based dynamicl earning process, which gives convergence analysis of EDDBN training process. Finally, the EDDBN-based soft-sensing model is used to predict the concentration of SO₂ in wet-flue-gas desulfurization system. The results show that it can efficiently and accurately predict the concentration of SO₂ under such non-stationary operating conditions, and the computational complexities of data set ① and data set ② are nearly reduced by 63.83% and 63.33%, respectively.

Folate-modified pH-sensitive copolymer P1 (FA-PEG-PHEMA-PDEAEMA) was prepared by end-bromination, esterification, and atom transfer radical polymerization (ARGET ATRP) reaction. Copolymer P2 (PCL-PHEMA-PEGMA) was synthesized by ring-opening, bromination, and ATRP reactions. The structure, molecular weight, and molecular weight distribution of the copolymers were tested by ¹H NMR, FTIR, and GPC. The CMC values of copolymers P1, P2, and mixed copolymer P1/P2 were 5.02, 1.58 and 2.51 mg/L, respectively, indicating that the copolymers could form stable micelles in solution. The drug-loaded micelles were prepared by dialysis method, and the morphology was spherical. The comprehensive drug loading performance and drug controlled release performance of mixed copolymer micelles MM were better than those of single copolymer micelles. Folate-modified drug-loaded micelles exhibited better inhibitory effects on HepG2 cells.

In recent years, the implementation of the “dual carbon” policy and advancements in related technologies has led to a significant increase in the proportion of wind and solar power generation in China. However, the intermittent and unstable nature of these renewable energy sources often results in the phenomenon of “curtailment” of wind and solar power. Hydrogen production through water electrolysis offers a solution by utilizing excess electricity and providing the advantage of zero emissions, thereby holding greater strategic significance compared to traditional hydrogen production methods. Anion exchange membrane water electrolysis (AEMWE), a technology developed over the past decade, integrates the benefits of alkaline water electrolysis (AWE) and proton exchange membrane water electrolysis (PEMWE), offering both high performance and economic advantages. Current domestic research on AEMWE predominantly focuses on the design and improvement of electrodes and membrane materials, with relatively limited studies on system simulation. Moreover, existing models often oversimplify the calculation of crucial parameters such as exchange current density and electrode resistance. To address these gaps, this paper integrates methodologies from other established electrochemical technologies (including AWE, PEMWE, and fuel cells) and relevant electrochemical principles. It introduces correction factors for effective exchange current density and bubble coverage, thereby enhancing the calculation methods for exchange current density. Additionally, a resistance network construction approach is employed to accurately represent electrode resistance. Building upon these methodologies, a more precise and broadly applicable semi-theoretical and semi-empirical steady-state electrochemical model for AEMWE is developed. The model's accuracy is validated using experimental data from existing literature. Finally, a sensitivity analysis is conducted to identify the key variables influencing the hydrogen production efficiency of AEMWE. The results show that membrane thickness, temperature and exchange current density are the main factors affecting the performance of the electrolyzer. Thinner membranes, higher operating temperatures and electrode materials with higher exchange current density are the development trends of electrolyzers.

The phase change material (PCM)-based direct absorption/storage solar collector (DASSC) has the advantages of less heat transfer process, lower thermal energy loss, and higher photothermal conversion efficiency. The PCM exhibits limited light absorption capacity and low thermal conductivity, leading to significant temperature gradients and a low heat transfer rate in DASSC. Current research predominantly addresses the heat storage process in DASSC, with insufficient focus on the characteristics of the heat release process. To address this gap, a photo-thermal conversion shaped composite PCM (CPCM) is prepared using a melt blending method in conjunction with a vacuum adsorption technique. The DASSC is subsequently developed, leveraging the high absorption and substantial heat storage density properties of the CPCM. The light absorption and phase change characteristics of the CPCM are tested, and the effects of inlet temperature and Reynolds number of the heat transfer fluid on the heat release characteristics of the DASSC are investigated. The sensitivity and correlation of these two parameters on the heat release rate of DASSC are analyzed using the Morris method. The findings indicate that the absorbance of CPCM is 3.03 times that of pure PCM. Additionally, when the inlet temperature decreases from 16.0℃ to 10.0℃, the average heat release rate of DASSC increases by 47.7%. As the Reynolds number increases from 2462 to 5628, the average heat release rate of the DASSC exhibits a 15.0% enhancement. The sensitivity and correlation of the inlet temperature on the heat release rate of the DASSC are significantly higher than those of the Reynolds number. The optimal value of the inlet temperature should be calculated separately in the design and optimization of the heat release performance of DASSC, while the Reynolds number can be directly determined based on the positive and negative correlation.

To solve the problem of spatiotemporal mismatch of energy in liquid hydrogen energy storage and to preferentially match suitable application scenarios, the cold energy is recovered by the combined cascade storage of liquid neon, liquid nitrogen, carbon dioxide (CO₂), and other working substances, and then the pre-cooled bypass hydrogen is incorporated into the liquefier to compensate the cold capacity and reduce the power consumption. Aspen HYSYS software is used to establish the processes of cold storage, cold release, and cold energy compensation. While giving priority to recovering cold energy in the low temperature zone, optimization is carried out from aspects such as coupling the waste heat utilization cycle of transcritical CO₂ fuel cells. The results showed that the non-pressurized cold energy storage was better to directly compensate the liquefier, and the hydrogen outlet temperature reached 273.7 K, while exergy efficiency was 81.65%. After pressurization, it focused more on increasing output work, and expanders generated more cold energy at high-temperature zones. For example, under the condition of expansion at 130 K, the hydrogen outlet temperature was 299 K, while energy efficiency was 86.07% and exergy efficiency was 50.86%. The simulation of hydrogen liquefaction cycles of helium two-stage expansion Brayton cycle and hydrogen dual-pressure Claude cycle showed that compensating cold capacity could effectively reduce the energy consumption and increase the exergy efficiency.

The rapid co-pyrolysis process of oil shale and bituminous coal was studied by thermogravimetric analysis, and the surface morphology and elemental composition of semi-coke were analyzed by SEM-EDS. At the same time, the product distribution law of the mixed pyrolysis of oil shale and bituminous coal was explored by using a self-made fixed fluidized bed reactor. The thermogravimetric results show that the synergistic effect is most obvious when oil shale accounts for 20%(mass) in the mixed fast pyrolysis process, and the maximum pyrolysis rate increases as high as 49.18%. The semi-coke morphology showed both massive pore structure and layered texture structure, and the content of carbon, oxygen and silicon on the surface of the micro-area varied in different degrees. The fixed-bed pyrolysis process further reveals the co-pyrolysis mechanism of oil shale and bituminous coal. The inorganic minerals in oil shale promote the removal of carboxyl groups in bituminous coal, significantly reduce the contents of phenols, alcohols and aromatic hydrocarbons in mixed pyrolysis oil, increase the yield of long-chain aliphatic hydrocarbons, improve the oil phase yield and improve the oil quality. Meanwhile, the active H radical in oil shale can increase the light hydrocarbon yield of CH₄ in the mixed pyrolysis gas, and increase the recovery value of pyrolysis gas.

The flow field, flame structure and heat release distribution of center-staged swirl combustion were measured by particle image velocimetry (PIV), OH-plane laser induced fluorescence (OH-PLIF) and CH* chemiluminescence, and the effect of fuel stratification on the characteristics of methane staged combustion was studied. Partially premixed methane/air mixtures were adopted in experiment, and the fuel stratification was attained through varied stratification ratios (SR) and global equivalence ratio. The results show that with lower SR, the primary recirculation zone (PRZ) expands radially due to combustion-induced thermal expansion, but with increased SR, radial contraction of the PRZ can occur. With increased SR, the pilot stage equivalence ratio is increased and the pilot fuel consumption is reduced, thus the remaining fuel can be transported downstream to react with the main stage excess air, which makes the HRR region move towards downstream; simultaneously, a small HRR region is formed in the PRZ with the remaining fuel. It is found that with lower SR, the main stage flame is stabilized by mixing its flame brush with the pilot stage, but with higher SR, combustion in the lip recirculation zone (LRZ) is also pronounced which contributes largely to the flame stabilization. Effects of the global equivalence ratio are similar to the SR, which can reinforce the fuel stratification and then cause expanded mixing region and weaken the pilot stage flame. Also, it enhances the LRZ combustion and makes it more essential for the main stage flame stabilization.

Alkaline water electrolysis is considered a key technology for sustainable hydrogen production. However, gas crossover at low current densities limits the load range of electrolyzers, introducing challenges in coupling them to renewable power sources. Current research primarily focuses on analyzing the mass transfer mechanism of impurity gases within the electrolysis cell, but it insufficiently considers the impact of shunt current in large-scale electrolyzers. Also, the dominant crossover mechanism is still under debate. This study investigated the relative contributions of different gas crossover mechanisms, including diffusive and convective transport mechanisms to gas crossover in electrolysis cells, circulated electrolyte mixing and shunt current electrolysis. A mathematical model for HTO (hydrogen-to-oxygen) calculation was established. To validate the HTO model, experiments were carried out in a fully automated industrial-scale alkaline water electrolysis system with a hydrogen production capacity of 1000 m³/h. The electrolyzer is equipped with the polyphenylene sulfide (PPS) diaphragm, and uses approximately 30%(mass) KOH. The results revealed that the HTO model's prediction aligns closely with experiment data, exhibiting a relative error of 4.1%. The model suggests that the overall crossover is primarily influenced by mixing the electrolyte cycles, which makes up a share of 64.42% at 500 A/m² and 17.4 bar (1 bar=10⁵ Pa), followed by hydrogen concentration gradient diffusion across the membrane, which accounts for 28.77%. Shunt current electrolysis and differential pressure convective crossover have relatively minor impacts on HTO, however, the presence of shunt current reduces oxygen production, which is an important indirect factor contributing to the rapid increase of HTO during low load conditions. Orthogonal experiments suggest that the separation pressure, flow rate, and electrolyte concentration have more significant impacts on HTO levels, while the electrolyte temperature exerts a relatively minor influence. Measures such as optimizing the operating parameters of the hydrogen production device and increasing the oxygen flow rate at low load can be taken to control hydrogen in oxygen. The research findings can provide a reference for the design and operation of large-scale renewable energy-coupled alkaline water electrolysis hydrogen production systems.

Pyrolysis can quickly achieve the harmless treatment and resource utilisation of low oil content landed oil sludge, but its high water content will cause a large amount of energy loss, and the energy balance problem in the pyrolysis process should not be neglected. In this paper, the pyrolysis experiments were carried out on the landed oil sludge, and the pyrolysis process was modelled using Aspen Plus software. By changing parameters such as initial water content, pyrolysis temperature, and coke combustion ratio, the possibility of achieving energy self-balance in the process system was analyzed. The results showed that the hydrocarbon content in the pyrolysis oil was as high as 71.6% at 450℃, and the pyrolysis oil obtained at pyrolysis temperatures lower than 450℃ was of high quality, with the proportion of C₆—C₃₀ exceeding 90%. At different pyrolysis temperatures, the coke combustion ratio does not exceed 100%, and the system can adjust the coke combustion ratio to achieve energy self-balance for the drying and pyrolysis process of grounded oil sludge. Lowering the initial water content of the sludge will help to reduce the energy consumption of the system, the lower the initial water content, the easier the energy self-balance of the system, such as after dewatering and treatment of the oil sludge is still high in water content, the process system can be used to increase the pyrolysis temperature to continue to maintain the energy balance.

Electrochemical water softening is a new type of green industrial circulating water scale inhibition technology. In response to the problem that parallel-arranged pole plates cannot effectively utilise OH^- and thus lead to low softening efficiency, an improved pole plate arrangement based on the simulation of the relative motion of circulating water and hydrogen bubbles is proposed. The passive diffusion of OH^- forms a long-term and effective alkaline area, which improves the utilization rate of OH^- and promotes the uniform nucleation of CaCO₃ crystals in the solution. The results showed that Ca²⁺ in the simulated circulating water was nucleated before reaching the cathode plate, and the number of CaCO₃ crystal particles was stable and the maximum size was up to 25 μm at 120 min, and the softening efficiency was up to 108.2 g/(m²·h) at the current density of 120 A/m², the flow rate of the water inlet of 12 L/h, and the initial hardness of 500 mg/L, and the cathode and anode center spacing of 61.5 mm. In this study, the use of air bubble movement and water flow regulation provides an innovative idea for electrochemical circulating water softening.

Extra-corporeal membrane oxygenation (ECMO) provides vital extracorporeal life support for critically ill patients. The main commercial oxygenating membrane, core component of ECMO, microporous polypropylene (PP) exhibits good gas permeability but easy blood leakage because of the micropores, while poly(4-methyl-1-pentene) (PMP) shows great difficulty in synthesis, and the hydrophobicity of both membranes often leads to poor blood compatibility. In this research, matrix mixed membranes LDH-PTFPMS/PEI, with the hydrophobic PTFPMS modified with the hydrophilic, bio-compatible and hydroxyl-group rich layered double hydroxide (LDH) as the dense functional separational layer and the microporous PEI membrane as the supporting layer, was synthesized, characterized for their structure as well as morphology, and evaluated for their performance in gas transfer and blood compatibility. The results showed that the addition of LDH promoted the permeability of CO₂ in the membrane. Compared with the original PTFPMS/PEI membrane, the CO₂ permeability of the 4% LDH-PTFPMS/PEI membrane increased by nearly 50% under normal pressure (0.1 MPa), and the membrane's anti-protein adsorption and platelet adhesion properties were improved, among which BSA protein adsorption was reduced by 21%.

The properties of novolac resins (NR) are closely related to the cross-linked network structure of the cured material, and the applications in various fields place higher demands on the properties of NR. However, there is a contradiction between the improvement of NR's strength, glass transition temperature (T_g) and toughness, and improving NR's strength, toughness and T_g at the same time is still challenging. In this study, the modifier named BEP was prepared by the reaction of epoxy-based polyhedral oligomeric silsesquioxane (EPOSS) and biphenyl phenolic resin (BN). The BEP+NR co-curing network with an inhomogeneous cross-linked structure was established, which improved the strength and toughness of NR. On this basis, the curing kinetics of BEP+NR was studied. Dense inhomogeneous crosslinked networks were obtained by modulating the homopolymerization of BEP, the co-curing of BEP and NR, and the self-curing of NR. Compared to NR, the T_g, flexural strength and impact strength of 1BEP+NR up to 146.3℃, 4.1 kJ/m² and 76.5 MPa, which were improved by 10.9℃, 78.2% and 50.9%, respectively. With the homopolymerization degree of BEP increased, the inhomogeneous of the crosslinked network further increased and the mechanical properties, thermal stability and T_g of BEP+NR decreased.

The rapid advancements in lithography within the integrated circuit industry have necessitated enhanced performance from photoresists. Organic-tin complexes show excellent properties in lithography resolution and line edge roughness, but their lithography sensitivity and film stability are relatively poor. This study presents an acrylic-coordinated triphenyl-tin carboxylate photoresist, designated as Sn1Ac, which is suitable for both deep-ultraviolet and electron-beam lithography applications. By forming hydrogen bonds with the additive tetrakis (3-mercaptopropionic acid) pentaerythritol ester, the instability of spin-coated films has been effectively eliminated, resulting in a photolithography film retention rate exceeding 93%. The hybrid films demonstrate excellent negative patterning properties. Under electron-beam lithography, these hybrid films achieve a resolution better than 15 nm and a line edge roughness of less than 2 nm. Through X-ray photoelectron spectroscopy and other testing methods, this paper proposed the synergistic cross-linking exposure mechanism of tin-carbonate and thiol-ene click reactions.

The secondary battery based on lithium-ion battery has entered the mainstream. LiNi_1-x-y Co _x Mn _y O₂ (NCM) material also has a considerable commercial market in lithium-ion batteries, and is a cathode material with great application value. It has different properties depending on the nickel content. The increase of nickel ratio can increase the specific capacity, but it will also lead to the decrease of thermal stability. Therefore, high-nickel materials require higher requirements on the preparation process to ensure their performance. Compared with Li[Ni_0.8Co_0.1Mn_0.1]O₂ (NCM811), Li[Ni_0.6Co_0.2Mn_0.2]O₂ (NCM622) has higher specific capacity and better thermal stability. The pure phase NCM622 material is prepared using a hydrothermal method, and the optimal preparation plan is obtained by controlling the calcination temperature and calcination time. The prepared NCM622 material can achieve a discharge specific capacity of up to 191.3 mA·h·g^-1 under optimal conditions, and the charge-discharge cycle can also have a capacity retention rate of up to 88.74%.

Carbon monoxide (CO) and carbon dioxide (CO₂) are crucial characteristic gases for detecting transformer faults, and their components can effectively reflect the operating status of transformers. To achieve rapid and precise detection of these gases, this paper introduces a novel material, boron (B)-doped nitrogen (N)-based graphene, for detecting dissolved characteristic gases CO and CO₂ in transformer oil. Utilizing density functional theory (DFT), the adsorption and activation behaviors of CO and CO₂ gases on B-doped graphitic-N、pyridinic-N and pyrrolic-N graphene substrates were investigated. Theoretical discussions were conducted on the changes in geometric structure, charge density, electron density of states, and band structure of B-doped nitrogen-based graphene (BN-X/G) following the adsorption of characteristic gases. The results indicated that the adsorption energies of CO and CO₂ on B-doped graphitic-N-based graphene were -0.18 and -0.20 eV, respectively, which have significant performance differences with other doped substrates and show stronger adsorption performance. Electronic localization function (ELF) configurations and Bader charge results revealed that CO and CO₂ transferred charges of 0.013 e and 0.009 e to the BN-G/G substrate, respectively, strengthening the interaction between the characteristic gases and the substrate. Density of states (DOS) outcomes suggested that B doping elevated the p-band center of N-G/G and led to noticeable orbital hybridization between B and graphitic-N atoms, forming covalent bonds that facilitated enhanced adsorption performance. This study provides valuable insights into the adsorption mechanisms of dissolved characteristic gases in transformer oil on heteroatom-doped graphene materials and offers rational guidance for the design of gas sensors.

Two approaches were employed to prepare a novel high performance composite heat storage material by using expanded vermiculite, magnesium sulphate and Trilatone X-100 as the layered porous substrate, reactive salts, and hydrophilicmodifier, respectively. Two different modification methods were used in the study and the performance of the composites prepared by the two methods was compared. The test results of scanning electron microscopy (SEM) and X-ray diffractometer (XRD) showed that magnesium sulfate/expanded vermiculite modified composites were successfully synthesized. The influences of modification approach, mass of the added Trilatone X-100, and relative humidity on the adsorption performance of composite materials were discussed. Thermal gravimetric analyzer (TG) and differential scanning calorimeter (DSC) were utilized to measure energy storage density of the adsorbed composites, the results indicated that the hydrophilic functionalized composite fabricated by the modified expanded vermiculite with the mass ratio of expanded vermiculite to Trilatone X-100 of 10 and magnesium sulphate exhibited the best heat storage performance, whose water uptake, desorption rate, and heat storage density were improved by 2.5%, 4.1%, and 9.1%, respectively, as compared to the non-functionalized one. After 10 cycles of adsorption-desorption testing, the water uptake of the hydrophilic functionalized composite was only reduced by 20.4%, showing favorable thermal stability.

A phase change emulsions is termed as a latent heat functional thermal fluid, which can not only maintain the fluidity of a conventional heat transfer fluid, but also have the latent heat storage capacity of phase change material. It is believed that the phase change slurry enables to enhance the heat transfer rate of a conventional heat transfer fluid, expanding the potential application fields and improving energy utilization efficiency. Two organic phase change materials were selected to prepare multi-melting point phase change emulsion, and its heat transfer was enhanced. Morphology, physical and chemical properties and thermophysical properties of phase change slurry were analyzed in detail. The results indicate that the obtained phase change slurry are milky white colloidal system at room temperature with average particle size range of 129.3—204.4 nm and excellent fluidity and stability. Multi-phase change temperatures appear in the phase change process, and the latent heat is in the range of 27.49—34.54 J/kg. Moreover, the solid specific heat and liquid specific heat range from 2.98 to 3.83 J/(g·K), and from 2.26 to 2.93 J/(g·K). Thermal conductivity of phase change slurry is between 0.42 and 0.47 W/(m·K), and 0.5%(mass) nano-Si₃N₄ can increase the thermal conductivity of slurry by 6.0%—13.5%. The enhanced phase change slurry can be used as an excellent heat exchange working medium in the field of cooling.

Conductive polymers could be used as electrode materials for supercapacitors and had great potential applications in small energy storage devices. This article used waste short pencils as raw materials to peel off the pencil core (PC) as a supporting substrate for supercapacitor electrode materials. Then, the ordered polyaniline (PANI) nanorod arrays were in situ grown on the surface of the pencil core by dilute solution method to form PANI@PC electrode. As a carbon material with good conductivity, pencil core could quickly achieve electron transfer and export when it combined with PANI with ordered micro/nano structure. Even at high scanning rates or current densities, the inner active material could still participate in electrode reactions, thereby improving the utilization of electrode materials to enhance the electrochemical properties of composite materials. The experiment showed that the specific capacitance of PANI@PC electrode could reach 470 F/g at a current density of 1 A/g, and the loss of specific capacitance is only 25.5% when the current density increases to 10 A/g. Further analysis of the charge storage mechanism of PANI@PC electrode shows that the electrode reaction is controlled by fast kinetics, that is, the double layer capacitance and Faradaic pseudocapacitance on the surface of PANI@PC electrode contribute, which is conducive to achieving good rate performance of electrode materials. This study could provide guidance for the preparation of composite conductive polymers/nanomaterials for supercapacitors.

In chemical parks with many hazardous chemicals and complex process units, once a fire or explosion accident occurs, it is easy to affect the neighboring units, thus triggering the domino effect and causing more serious consequences. To explore the dynamic evolution of the fire domino ^{effect and the synergistic effect on the domino accident escalation, a quantitative assessment of the domino effect is conducted. Based on the thermal response mechanism of the storage tank and considering the dual effects of material failure due to thermal radiation and the increase in internal pressure, a transient response model of time to failure and escalation probability of the tank is developed by integrating factors such as temporal-spatial evolution and synergistic effects of multiple fires. A certain tank area was simulated as the research object, the initial accident was set, and the domino effect in the scene was dynamically modeled and analyzed. The results show that the synergistic effect between multiple fires will increase the rate of temperature rise of the storage tanks and significantly reduce the failure time of the tanks, which will accelerate the upgrading of the domino effect. The dynamic domino effect model established in the research can predict the failure time and the probability of the storage tanks, and then determine the upgrading path of the domino effect, and at the same time, analyze the targeted chain-breaking strategy to block the propagation of the accident according to the results, so as to provide a theoretical basis for the allocation of safety protection and the formulation of emergency measures in the chemical park.}

CO₂ pipelines is a key link of CCUS technology, when it encounters leakage, corrosion and other damage, it is necessary to vent the pipeline first to carry out subsequent repair work. In order to ensure the safety of the venting operation, it is necessary to evaluate the potential danger of dry ice generation and the risk of valve freezing during the venting process. In this paper, based on the industrial-scale CO₂ pipeline throttling experimental device, two groups of supercritical phase venting experiments with different throttle valve openings were performed. The results showed that during the direct venting process, a dry ice zone (length shorter than 149.2 m, height lower than 58.3 mm) appeared at the injection end of the main pipeline at the later stage of the venting, and that the generated dry ice particles had migration phenomena. The minimum temperature of the vent pipe drops to -23.2℃, and the subzero low temperature continues for 600.4 s. Although the throttling effect can improve the minimum temperature of the dry ice area at the injection end, but dry ice accumulation occurs at the discharge end (the length of the accumulation is shorter than 10.4 m, and the height is lower than 116.5 mm). The throttling effect can reduce the pressure filling level of the vent pipe (pressure reduction of 40%), but will also reduce the temperature drop of the vent pipe (the lowest temperature down to -35.4℃) and increase the potential danger of valve freezing.