Itaconic acid (IA) is one of the important raw materials in chemical production and one of the most promising high-value-added platform compounds. It can replace petroleum-based acrylic acid and methacrylic acid. Furthermore, itaconic acid possesses significant pharmacological properties, such as anti-inflammatory, antiviral, and immune regulation functions, positioning it as a prospective drug candidate molecule in pharmaceutical research and development. In light of both domestic and international research advancements, this article provides a comprehensive review of the biosynthetic pathways and recent progress in the biosynthesis of itaconic acid. Additionally, it addresses strategies for enhancing itaconic acid production and offers an outlook on prospective research directions in the realm of itaconic acid.

Streptomyces chassis development is an effective strategy for the high-efficient synthesis of microbial source nature product, and highly efficient gene editing tools provide a powerful tool for the construction of Streptomyces cell factories. CRISPR (clustered regularly interspaced short palindromic repeats) technology is accurate, universal and easy to operate, and has been widely used in microorganisms. However, off-target effects, cytotoxicity and low editing efficiency limit application of CRISPR genome editing in Streptomyces. This article summarizes the application and optimization strategies of CRISPR-related technologies in Streptomyces, and looks forward to the application prospects of CRISPR systems in Streptomyces cell factories, providing a reference for the development of efficient gene editing tools suitable for Streptomyces.

With the extensive use of fossil fuels, the emission of carbon dioxide (CO₂) has increased year by year, causing global climate problems. To address this global issue, carbon capture, utilization, and storage (CCUS) is considered an important means to slow down CO₂ emissions. Currently, organic amines are commonly used as CO₂ absorbents, but their high regeneration energy consumption leads to high capture costs, which hinders the commercial deployment of CCUS. As a low-energy consumption absorbent, the liquid-liquid phase change absorbent, formulated with organic amines, functions as a solution capable of compensating for this deficiency. Liquid-liquid phase change absorbents are homogeneous under normal conditions, but phase change can be triggered when the polarity, hydrophilicity, or hydrogen bond strength changes, resulting in the formation of a CO₂-lean phase and a CO₂-rich phase. Only one phase enriched in CO₂ is sent to regeneration, thus reducing regeneration energy consumption.This review summarizes the research progress of liquid-liquid phase change absorbents in recent years, and compares key aspects such as phase change characteristics, phase change mechanism, absorption loading, and regeneration energy consumption. Finally, combined with the demand for CO₂ capture, other research contents that need to be improved are pointed out and future research directions are prospected.

Electrochemical double layer capacitor (EDLC) has attracted much attention due to its high power density, long cycle life and rapid charging capacity. However, the stability and reliability of EDLC are critical for practical applications. To improve the stability and extend life, it is important to understand the mechanism of performance attenuation and failure. This paper discusses the failure criteria of EDLC and methods for monitoring and in-situ electrochemical characterization of performance degradation. By reviewing research progress on the failure of EDLC, it focuses on key components such as electrode materials, electrolyte, electrode/electrolyte interface and current collector, with the purpose of revealing the failure phenomena and mechanisms in different systems. Finally, we look forward to the development direction and challenges of high stability EDLC, emphasizing the development and characteristics of new materials, and providing strategies for performance optimization and application expansion.

Molten salt heat storage technology is widely utilized in solar thermal power generation, power peak regulation, and the consumption of renewable energy, and the key is molten salts. Based on phase diagram thermodynamic calculation, this paper designs NaCl-KCl-ZnCl₂ and NaCl-KCl-CaCl₂ molten salts. The melting point of the designed NaCl-KCl-ZnCl₂ molten salt is 36.6℃ lower than that of the current commercial Solar Salt. The limit operating temperature of NaCl-KCl-CaCl₂ molten salt is 747.5℃, which is greater than the minimum operating temperature of molten salt required for the next generation of solar thermal power generation. The effect of carbonized loofah sponge fragments (CLSF) on the thermal transient response performance of NaCl-KCl-CaCl₂ molten salt is analyzed by combining infrared imaging and digital image processing technology. Compared with the ternary molten salt NaCl-KCl-CaCl₂, the maximum melting enthalpy of NaCl-KCl-CaCl₂/CLSF molten salt is decreased by 27.09%, the maximum thermal conductivity increased by 60.03%, and the heating time and cooling time in the same temperature range decreased by 62.50% and 39.13% respectively. Efficient heat conduction channel inside the composite molten salt is formed by CLSF, resulting in significantly improved the heat storage performance of the composite molten salt. The phase transition behavior and thermal stability of the ternary molten salt are not affected. It can be concluded that NaCl-KCl-CaCl₂/CLSF composite molten salt has good thermal conductivity, thermal stability and heat storage performance, and broad application prospects.

The development of shell-and-tube condensers for large-scale high-efficiency heat pumps requires the film condensation heat transfer characteristics when new environmentally friendly working fluids are combined with high-efficiency condenser tubes. This study experimentally determined the film-boiling heat transfer characteristics of R1234ze(E) on the outside of a horizontal high-efficiency condensing tube and compared the differences in film-boiling characteristics between R1234ze(E) and R134a on the outside of a horizontal three-dimensional finned tube. A model for the film-boiling heat transfer coefficient of R1234ze(E) on the outside of a horizontal novel three-dimensional finned tube was established. The experimental high-efficiency condensing tube used was T2 copper with an outside diameter of 19.05 mm, a height of 0.9 mm, a fin density of 1811 fpm on the bottom and 77 fins per circumference on the top. The results show that at a condensing temperature of 38℃, the heat flux increased from 23.6 kW/m² to 46.1 kW/m², and the film-boiling heat transfer coefficient of R1234ze(E) on the outside of the experimental three-dimensional finned tube α_o,1234ze(E) decreased from 30.9 kW/(m²·K) to 26.5 kW/(m²·K) (a decrease of 14.2%); at the same heat flux (37.6 kW/m²), the condensing temperature increased from 30℃ to 46℃, α_o,1234ze(E) decreased from 33.9 to 24.3 kw/(m²·k) (a decrease of 28.3%); at the same heat flux conditions, the film-boiling heat transfer coefficient of R1234ze(E) on the outside of the experimental three-dimensional finned tube could be up 22.9 to 24.5 times that of a smooth tube; at the same condensing temperature (38℃) and heat fluxes ranging from 10 to 50 kW/m², the film-boiling heat transfer coefficient of R1234ze(E) on the outside of the experimental three-dimensional finned tube was 1.09 to 1.25 times that of R134a. A new three-dimensional horizontal external condensation heat transfer coefficient model for R1234ze(E) is established, and the deviation between the predicted value and the experimental results is ±3.0%. The research results have reference value for the development of high efficiency shell and tube condenser for heat pump by using R1234ze(E) and new three-dimensional ribbed tube.

To further optimize the insulation performance of multi-layer insulation structures applied to liquid hydrogen storage, a sequential quadratic programming algorithm was proposed to optimize the radiation shield spacing of continuous variable density multi-layer insulation coupled with vapor cooled shield (VCS). The effects of the position of the VCS, the quasi-positive transformation within the VCS and the number of VCSs on the optimal radiant screen spacing distribution and adiabatic performance were studied. The results show that the introduction of VCS causes a sudden change in the optimal spacing distribution of radiation shields at the location where the VCS is set, and the heat leakage flux density q_in after optimization can decrease by up to 36.1% compared with that before optimization. Under condition that the optimization is adopted, the introduction of para-to-ortho hydrogen conversion can achieve a maximum decrease of 28.3% in q_in. The increase in the number of VCS significantly reduces the spacing between the innermost radiation shields. When the number of VCS is increased to 2, the minimum q_in decreases by 50.4% compared to the single VCS.

The thermal process calculation software of the evaporative condenser was compiled on the MATLAB platform. The thermal performance of the horizontal circular tube falling film evaporative condenser was calculated and analyzed. This study thoroughly explored the impact of various factors, such as the wind speed outside the tube bundle and the water spray density, on crucial parameters including heat transfer, external heat transfer coefficient, and mass transfer coefficient. The results of the calculations indicate that an increase in the head-on wind speed significantly enhances the heat transfer efficiency. This improvement is largely attributed to the disturbances that the wind creates on the liquid film outside the tubes, which, in turn, has a profound impact on the mass transfer processes as well. Notably, when the wind speed reaches approximately 4.21 m·s⁻¹, a critical threshold is observed where the trends of the outlet air temperature and humidity reverse, further intensifying the evaporation of the liquid film. Additionally, the study found that increasing the water spray density can lead to a slight improvement in heat transfer, it also results in a rise in the temperature of the water film on the tube surfaces. This temperature increase, coupled with a reduction in the outlet air humidity, can actually impede both heat and mass transfer processes. Consequently, it was determined that there exists an optimal spray density, which is approximately 0.068 kg·m⁻¹·s⁻¹, where the benefits of increased spray do not offset the drawbacks of higher water film temperatures.

The traditional serpentine structure and topological structure flat plate pulsating heat pipes were made on alloy copper by wet etching technology. With R141b as the working fluid, the start-up and heat transfer performance differences and change laws of the above two heat pipes under local heating (heating area 15 mm×15 mm, 20 mm×20 mm and 25 mm×25 mm) were compared and studied. Experimental results show that both traditional and topological optimized OHPs exhibit improved start-up and heat transfer performance with increasing local heat source area. Compared to the traditional OHP, the topology-optimized design concentrates the channels around the local heat source, effectively expanding the evaporation/boiling area in the heating section and minimizing the influence of the heat source area on its start-up and thermal performance. For the traditional OHP with multiple local heat sources, the start-up behavior can be categorized into two types: 'abrupt' and 'gentle', which resemble the start-up characteristics observed with a single uniform heat source. In contrast, the topologically optimized OHP only displays a 'gentle' start-up behavior, with no abrupt temperature changes observed under any conditions. The topological design significantly improves the overall temperature uniformity and the heat transfer limit of the OHP, particularly improving heat transfer performance for smaller heat source areas and medium-low heating powers. For instance, when the heat source area is 15 mm×15 mm and the heating power is approximately 75 W, the effective thermal conductivity of the topologically optimized OHP increases by about 41.8% compared to the traditional design. The optimized channel layout mitigates the limitations of traditional OHPs in dissipating heat from multiple localized sources, offering superior temperature uniformity and heat transfer capacity, thus expanding the application potential of OHPs.

To solve the heat dissipation problem of high heat flux electronic components, a novel multi-loop flat-type loop heat pipe with a size of 200 mm×150 mm×30 mm was prepared. The heat pipe adopts a design that couples an array of pin-fins on the evaporation surface with multiple gas-liquid pipelines, which can improve heat transfer efficiency in a limited space. The effects of heat flux, filling ratio, and working fluid properties on the thermal performance of loop heat pipe, and the startup characteristics of loop heat pipe under different heat load were studied. The heat performance of loop heat pipe under single and multi-source heating conditions was compared. The results show that the new loop heat pipe starts quickly, with a startup time of only 52 s at 300 W heat power, and the surface temperature fluctuation of the heat source after steady state is less than 0.3℃. When heated by three heat sources simultaneously with a total heat load of 388.8 W (the heat flux of main heat source can reach 133 W/cm²), the heating surface temperature is less than 85℃, and no dry burning occurs in the evaporator, effectively satisfy the heat dissipation requirements of high-power and high heat flux electronic devices.

The CLSVOF model and dynamic adaptive grid were used to numerically simulate the impact-coalescence process of double droplets on the concave-wall in still water. The results indicate that double droplet coalescence behavior occurred during the rolling and sliding process on the concave-wall with the underwater oleophobic materials, the droplet spreading edges contacted and coalescented after impact on the underwater oleophilic surface. The spreading diameter d, the endpoint distance of double droplets on the concave-wall δ, and the maximum spreading factor β were used to classify three liquid bridge forms. For β≤3.1, droplets coaled and formed a single liquid bridge. For β>3.1 and δ/d<3, a hollow ring with high pressure at the inner edge was formed when the right droplet impacted on concave-wall, and double liquid bridges were formed because of the expansion of the oil droplet spreading area. For β>3.1 and δ/d≥3, a single liquid bridge with a hollow ring was formed, but the wetting area fluctuated after coalescence. The single liquid bridge formed by the coalescence of double droplets has a larger dimensionless flow area. The single liquid bridge was more stable than the double liquid bridge. However, double liquid bridge shortened the duration of the impact wall to coalescence. The discoveries provided a useful theory for understanding the collision and coalescence mechanisms of heterogeneous phases near the cyclone wall. The shortcoming of the coalescence theory on discrete phase droplets was supplemented.

Static mixer is a kind of efficient and energy-saving mixing equipment with broad applications in chemical engineering and environmental protection. The unique morphological structures of natural organisms provide rich inspiration for the design of high-efficiency equipment. The three-twisted conch static mixing element has been designed, which was inspired by the spiral shape of the conch. The enhanced heat transfer performance of the three-twisted conch static mixer (TCSM) and the reverse three-twisted conch static mixer (RTCSM) were evaluated and compared. In the constant heat flux heat transfer experiments, pressure drop (Δp), Fanning friction factor (f), and Z-factor were used to evaluate the performance of energy consumption. Meanwhile, Nusselt number (Nu), convective heat transfer coefficient (h), and preference evaluation criterion (PEC) were utilized to evaluate the enhanced heat transfer performance of different mixers at Reynolds numbers (Re_t) ranging from 2640 to 11450. The results indicate that compared with the empty tube, the h of the Kenics static mixer (KSM), TCSM, and RTCSM are enhanced by 22.15%—40.53%, 10.83%—27.34%, and 33.29%—50.30%, respectively. The PEC of the RTCSM is higher than that of TCSM and KSM by 9.41%—28.99% and 4.94%—13.29%, respectively. Additionally, the power spectral density (PSD) and scaling exponent (ϕ) of the pressure signal time series at the inlet and outlet of different mixers were analyzed. The results indicate that due to the large-scale macroscopic motion of the liquid phase, the PSD strength of KSM is greater than that of TCSM and RTCSM in the low-frequency range. Concurrently, the ϕ of RTCSM is lower than others, which indicates that RTCSM generates more small-scale vortices and dissipation leading to a higher energy proportion of the high-frequency range. The maximum Lyapunov exponent (λ) of RTCSM at the outlet is larger than the λ of TCSM and KSM, indicating that the fluid exhibits stronger chaotic characteristics after flowing through RTCSM.

MnO coating was prepared on the surface of 310S alloy by electrodeposition-low oxygen partial pressure method. The coking inhibition performance of the coating was evaluated under the conditions of naphtha pyrolysis, and the phase transformation process of MnO _x components during the cracking-decoking cycle was systematically investigated. X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy and Raman spectroscopy were used to characterized the phase composition, surface morphology, chemical valence state and chemical structure of the coating and coke deposits. The results showed that the MnO coating was smooth and dense with the thickness of about 45 μm. When the cracking time was 3 h and 5 h, the coking inhibition rate of MnO coating was 75.84% and 74.22%, respectively. However, MnO phase in the coating was changed with the cracking/decoking cycles, which led to a poor adhesion between the coating and the alloy substrate and a rapid decrease in coking inhibition effect subsequently. Overall, the coating maintained an excellent anti-coking effect in the 3 cracking/decoking cycles. The results in this paper are expected to provide the guide for the development and application of the manganese oxide coating with an ability of catalyzing coke oxidation.

Safe hydrogen storage and efficient hydrogen production are critical challenges for the large-scale application of hydrogen energy. Utilizing methanol as a hydrogen storage medium and achieving mild continuous on-site hydrogen production through photo-driven methanol-water reforming is an effective approach for utilizing hydrogen energy. However, slow hole transfer kinetics and methanol dehydrogenation oxidation rate are bottlenecks that limit the performance of photocatalytic hydrogen production from methanol aqueous solution. Herein, based on the regulation of catalyst nanostructures, we constructed one-dimensional long diameter nanorod-like Zn_0.5Cd_0.5S (ZCS-LNR) photocatalyst to accelerate the photogenerated charge carrier separation and migration efficiency. By introducing NaOH alkaline medium, the rapid activation of OH^- and efficient dehydrogenation ability of ·OH are harnessed to facilitate surface hole transfer and enhance the rate of methanol oxidation dehydrogenation through the OH^-/·OH redox couple, thereby achieving high-performance hydrogen production from an alkaline methanol aqueous solution. Among them, the ZCS-LNR catalyst can obtain a hydrogen production rate of 54.33 mmol/(g·h) under the conditions of room temperature, 1.0 W/cm² light intensity, 4 mol/L NaOH and a CH₃OH/H₂O volume ratio of 1∶1. This study provides a novel feasible reaction pathway for achieving efficient photocatalytic hydrogen production from methanol aqueous solution.

Zeolite materials have important application value in the field of adsorption separation. The intracrystalline diffusion behavior of adsorbates in zeolite is one of the important bases for evaluating their adsorption separation effect. The zero length column (ZLC) technique was developed to evaluate intracrystalline diffusivity. This method involves placing a minute quantity of adsorbate between sieve plates and applying a high flow rate of carrier gas, while maintaining the relative partial pressure within the Henry region. The traditional ZLC experiments rely on the bulging method to produce organic vapors with varying partial pressures, which is not suitable for organic molecules with low saturated vapor pressures. To address these limitations, an inverse gas chromatography (IGC)-based ZLC apparatus, complemented by a micro-syringe pump was developed for evaluating the intracrystalline diffusion coefficient. In the IGC-ZLC apparatus, the adsorbent is loaded into a specialized column. A micro-syringe pump continuously injects the adsorbent liquid into the inlet port at a set temperature. The liquid then vaporizes and enters the column, with the eluting molecules detected by a flame ionization detector (FID). The intracrystalline diffusion coefficient is derived from the resulting elution curve. n-Octane, an organic molecule with a low saturated vapor pressure was selected as the adsorbate and ZSM-5 was selected as the adsorbent. The accuracy of the self-developed IGC-ZLC methodology across a range of conditions, including varying partial pressures, carrier gas flow rates, injection volumes, and temperatures was validated. Moreover, the hexane, heptane, nonane, isooctane and cyclooctane were also selected as absorbate for comparison. This work presents a promising new approach for determining intracrystalline diffusion coefficients.

The lattice energy is a critical physical property determining the thermodynamic stability of crystals and holds instructive significance in screening the stability of polymorphism. Lattice energy is usually obtained by experimental trial and error as well as theoretical calculation based on molecular/quantum mechanics. For a large number of crystal structures, both methods are time-consuming and laborious. In this paper, a lattice energy regression model based on density functional theory (DFT) and crystal graph convolutional neural networks (CGCNN) is proposed. First, the lattice energies were calculated using the range-separated self-consistent screened many-body dispersion corrected DFT method. A dataset comprising lattice energies for 248 crystal structures including acids, alcohols, amides, amino acids, and anhydrides was established. Subsequently, leveraging this dataset, a crystal graph convolutional neural networks model was employed to establish a quantitative regression model for the relationship between crystal structures and lattice energies, which demonstrated promising predictive performance with mean absolute percentage error (MAPE) values of 1.24% for the training set and 5.04% for the test set, and R² values of 0.9978 and 0.9750, respectively. The results show that the model has a good predictive performance which can provide theoretical guidance and technical support for high-throughput screening of stable crystal forms.

Driven by the goal of carbon dioxide peaking and carbon neutrality, it is of great social and economic significance to develop green chemical technologies, such as the substantial use of H₂ generated by water electrolysis with offshore wind power and CO₂ separated from CO₂-rich natural gas to produce green methanol is gaining significant socioeconomic and environmental relevance. However, how to efficiently separate carbon dioxide from marine carbon-rich natural gas has become a key technical difficulty. Conventional high-throughput screening methods for metal organic frameworks (MOFs) to separate actual natural gas component CO₂ face the problems of high model complexity and long solution time. Therefore, a machine learning-assisted high-throughput screening strategy is proposed. The R² values on the training set and the test set are more than 0.98 and 0.92, respectively, which can be used to quickly and efficiently separate CO₂ from the actual natural gas of six components (N₂, CO₂, CH₄, C₂H₆, C₃H₈, H₂S).

Hydrogen is an essential chemical raw material in refineries, and hydrogen network synthesis is a method that allows optimization of hydrogen distribution as well as other equipment configurations. Among all the costs of the hydrogen network, the compressor cost accounts for a relatively large proportion, and a very fundamental propose in the hydrogen network optimization is obtaining a reasonable compressor arrangement. In order to optimize the compressor arrangement and the hydrogen distribution of the hydrogen network, this paper proposes a grouped-compressor hydrogen network model with the minimum total annual cost as the optimization objective. The model divides the compressors into three groups of hydrogen source compressors, hydrogen sink compressors, and stream compressors according to the location of the compressor arrangement, which can consider the case of shared as well as series-connected compressors. In addition, in order to reduce the difficulty of model solution, reasonable simplification measures are proposed. Finally, after the case study, the compressor group cascade model and the simplified model are significantly better than the basic model, with the total number of compressors reduced and the compressor-related costs decreased by 1.5%-2.1%, which proves the validity of the present model.

For the catalytic reaction system, the reactor acts as the core of material conversion, and its key lies in selecting highly active catalysts. During production, catalyst activity decreases with the passage of operating time, affecting the reactor performance and the operation of subsequent devices. Clarifying system parameters' changing rules and making corresponding deactivation compensation measures is of great significance in strengthening system performance and reducing production costs. Based on separable reaction kinetics and mass/energy balance, correlation models targeting the relation between the reaction performance, reactor operating parameters, and running time are established. According to the topology analysis, pinch analysis, and cascade effect analysis, the time-varying law of each device's and system's energy requirement is revealed. On this basis, an economic evaluation index considering system integration is constructed to guide catalyst regeneration and system parameter optimization. A benzene selective hydrogenation to cyclohexene process is taken as an example, with the system performance/operating parameters' time-varying characteristics visually displayed. The catalyst's optimal regeneration cycle is determined as 1.92 a. Compared with the literature results, the optimized service life is closer to the engineering value, with the average production cost per unit product reduced by 5.2%.

When using the lattice Boltzmann method (LBM) to simulate the slug flow with low capillary number, the bubble development process is complex and the model control parameters are difficult to select. When the selected parameters are inappropriate, erroneous non-physical phenomena will occur, thereby reducing the calculation accuracy. The LBM multiphase flow process model is established through machine learning, and the particle swarm algorithm is used to optimize the hyperparameters of the machine learning model, and further optimize the control parameters in the LBM modeling process. In this paper, a coupled multiphase flow numerical simulation model of LBM-machine learning-particle swarm algorithm is established. Based on this model, the influence of the flow parameters of the elastic flow in the T-shaped microchannel on the stability of the bubble evolution process is investigated. The simulation results show that the proposed LBM multiphase flow model can predict the bubble elongation rate under complex conditions, based on which the optimal gas-liquid two-phase inlet flow rate relationship is found through elongation rate analysis, which effectively solves the problem of elastic flow instability under low capillary number, and significantly improves the simulation calculation accuracy and computational efficiency.

Accurate and rapid simulation of chemical engineering units is crucial to the success of chemical process digital twins. As one of the most complex and widely used units in chemical engineering, the efficient and accurate solution of distillation columns is essential for the implementation of digital twins in chemical plants. However, traditional distillation column model has become a bottleneck restricting its digital twin due to its large scale and time-consuming calculation of thermodynamic properties. To address this, a efficient and short-cut distillation column model for hydrocarbon systems was developed based on the short-cut distillation column model by introducing the correlation between component equilibrium constants and temperature, thereby simplifying the phase equilibrium calculations. The model was validated by using a distillation column from an actual industrial process. The results show that the proposed efficient and short-cut distillation column model significantly reduces computation time, laying a solid foundation for digital twin modeling of distillation columns.

Soft sensor techniques provide an effective solution for the predicting of important and hard-to-measure variables in industrial processes. However, due to the complexity of industrial processes and the high cost of data acquisition, the distribution of labeled data and unlabeled data is unbalanced. At this point, constructing high-performance soft sensor models becomes a challenge. To address this problem, a multi-output tri-training heterogeneous soft sensor based on time difference is proposed. By constructing a new tri-training framework, three models, namely MGPR (multi-output Gaussian process regression), MRVM (multi-output relevance vector machine), and MLSSVM (multi-output least squares support vector machine), are used as baseline supervised regressors that are trained and iterated using labeled data; Meanwhile, the TD (time difference) is introduced to improve the dynamic characteristics of the model, and the parameters of the model are optimized by KF (Kalman filtering) to improve its prediction performance. Finally, the model was validated by simulating the wastewater treatment platform (benchmark simulation model 1, BSM1) and an actual wastewater treatment plant. The results show that the model can significantly improve the adaptive and predictive performance of the soft sensor model under the imbalance of data distribution compared with the traditional soft sensor modeling approach.

The sealing rings with soft-hard pairing are extensively applied in the field of rotary dynamic sealing. However, the contact friction between the static and dynamic rings is the main cause of sealing failure. Analyzing the contact characteristics of the seal ring is important for studying the seal friction damage phenomenon and even predicting the stable operation of the seal. Traditional studies are mostly based on the assumption that the micro-surface micro-convexities of the sealing rings satisfy the single-layer characteristic of Gaussian distribution, ignoring the existence of stratification characteristics. This paper, based on the engineering background of dry gas seals, measures the two-dimensional data of the surface topography of the sealing ring, uses the discontinuous separation method to obtain layered parameters, reconstructs the sealing ring in three dimensions using the dual-Gaussian surface simulation theory, studies the contact characteristics of the sealing ring using a deterministic contact model, and analyzes the effects of related length, lower Gaussian roughness, and upper Gaussian proportion on the sealing contact characteristics in combination with surface simulation. The results show that polished finished carbon graphite sealing ring with distinctive stratified characteristic. An increase in the correlation length reduces the number of rough peaks and increases their average radius of curvature. The increase of the upper Gauss ratio leads to a slight increase in the mean curvature radius of the rough peaks. Increasing the lower Gaussian roughness will decrease the average curvature radius of rough peaks, increase the number of rough peaks, and significantly reduce the contact performance. The lower Gaussian roughness has the greatest influence on the surface morphology and contact characteristics, while the correlation length and upper Gaussian ratio have little influence on the contact characteristics.

Different series of carbonized metal-organic frameworks (cMOFs) were prepared through high-temperature carbonization and applied for the fabrication of microreactors with Burkholderia cepacia lipase (BCL). The effects of pore structure and pore microenvironment on the immobilization performance of BCL were studied, and the performance of these microreactors in catalytic resolution of mandelic acid enantiomers was explored. The results indicated that the cMIL-53(Al) material from cMOFs exhibited the best immobilization performance for BCL, maintaining a (R)-mandelic acid conversion rate of 50% and an enantiomeric excess (ee_p) value over 99% in nine consecutive catalytic cycles, with an enzyme selectivity (E) value greater than 200. The high-temperature carbonized cMIL-53(Al) showed increased inter-pore structure, allowing BCL to effectively enter the cMOF structure and increase the spatial activity sites of BCL. Additionally, its surface is rich in carboxyl functional groups, enabling BCL to adsorb and immobilize through hydrogen bonding, significantly enhancing the catalytic efficiency. Compared to traditional organic base catalysis methods, the enzyme-immobilized microreactors proposed in this study have the advantages of reusability, short catalytic time, ease of product purification and separation, and lower environmental pollution. This provides a new strategy for the construction of novel enzyme-immobilized functional materials.

Pressurizing the heat release (carbonation) process in CaCO₃/CaO thermochemical energy storage cycle can significantly improve the cyclic heat storage performance of calcium-based materials. The carbonation cycle heat storage performance of TiO₂-doped calcium-based materials (CaCO₃-TiO₂) under pressurized conditions was studied. The influences of TiO₂ doping amount, carbonation pressure, temperature and cycle times on the heat storage performance of CaCO₃-TiO₂ were discussed. The results show that when doped with 5% (mass) TiO₂, CaCO₃-5TiO₂ is more alkaline than pure CaCO₃, the carbonation reaction proceeds more easily, and the cyclic heat storage performance is the best. The increase of carbonation pressure can enhance the heat storage performance of CaCO₃-5TiO₂, but the enhancement range decreases with the increase of pressure. Under the best working condition (0.8 MPa, 850℃), after 30 cycles, the heat storage density of CaCO₃-5TiO₂ is 1829 kJ/kg, which is 23% higher than that under normal pressure, and 2.9 times higher than that of pure CaCO₃ under normal pressure. SEM/TEM and BET characterization shows that CaTiO₃ produced by the reaction of TiO₂ with CaO effectively relieves the sintering and agglomeration of the material. After 30 cycles, the specific surface area and pore volume of calcined CaCO₃-5TiO₂ are 2 times and 1.4 times that of calcined pure CaCO₃. It has more stable pressurized carbonation cycle heat storage performance.

This study constructs a hybrid energy power generation and hydrogen production system model including wind power, thermal power, batteries and electrolytic hydrogen production equipment to explore the economic benefits of large-scale wind-thermal power generation and hydrogen production systems under different operating strategies. Focusing on a 700 MW wind farm and a 350 MW thermal power plant, the study employs three strategies: green electricity hydrogen production, green electricity-valley electricity hydrogen production, and green electricity-thermal power hydrogen production. A mixed-integer model is established to maximize annual profit, analyzing system performance under various wind resources and electrolyzer capacities. The results indicate that wind resources and electrolyzer capacity significantly influence system performance and strategy selection. In wind-rich conditions, green electricity-thermal power hydrogen production is optimal with a 500 MW electrolyzer capacity. In wind-scarce conditions, the green electricity-valley electricity strategy with a 400 MW capacity offers the best economic performance while maintaining lower carbon emissions. A combined approach using the green electricity-valley electricity strategy during wind-rich seasons and green electricity-thermal power strategy during wind-poor seasons can achieve maximum annual profit within reasonable carbon emission limits. Furthermore, the study analyzes the impact of hydrogen production system investment costs and carbon trading mechanisms on hydrogen prices. It reveals that as investment costs decrease and carbon emission-related costs increase, the green electricity hydrogen production strategy becomes more economically viable in the future.

To systematically analyze and evaluate the thermodynamic performance and economic viability of offshore wind power-based hydrogen production systems, a comprehensive model was developed that integrates both auxiliary equipment from a thermodynamic perspective and accounts for the unique characteristics of the marine environment within an economic context. Using this model, parameter studies and sensitivity analyses were conducted to investigate the effects of operational parameters on system performance. Subsequently, a case study was conducted using actual wind speed data from Chinese marine areas to simulate and assess hydrogen production capacity and system performance for that region. The results indicate that increases in wind speed, electrolyzer operating temperature, and operating pressure significantly enhance system performance, with the system being most sensitive to variations in wind speed. The case study showed that the annual hydrogen production in this marine area reached 179908 kg, with average energy efficiency and exergy efficiency of 26.6% and 54.4%, respectively. However, the high costs associated with offshore floating structures significantly increased the levelized cost of hydrogen. In addition, the hydrogen production capacity of this sea area is obviously insufficient in summer, especially the lowest hydrogen production in June, which is only 15.3% of that in October or November.

Nitrous oxide and fuel blend (NOFBX) has been considered as potential hydrazine replacement due to their advantages of non-toxic, high-performance, and low-cost as monopropellant. The methane and nitrous oxide (CH₄/N₂O), a typical NOFBX combination, provides significant benefits for meeting propulsion performances and has become a focus of increased research in recent years. In addition, N₂O and CH₄ can be stored in one premixed tank, which would increase the risk of ignition of premixed fuel and oxidizer at high self-pressurized condition. However, limited data has been published on the ignition safety and ignition delay time (IDT) of CH₄/N₂O at high pressure, resulting in unclear understanding of the ignition hazards and mechanisms. In this work, the ignition behaviors of Ar diluted CH₄/N₂O were experimentally investigated firstly in a heated rapid compression machine (RCM) by detecting the pressure and light emission traces at temperatures and pressures ranging from 1125—1450 K and 10—40 bar. The critical ignition temperature which separates the non-ignition and ignition cases was determined. The results show that the critical ignition temperature decreases with the increases of pressure and fuel/oxidizer concentration. For the successful ignition cases, the ignition delay times were measured and used to validate several recently developed kinetic mechanisms. The results show that the IDT predictions from Yang model have good agreement with the measured IDTs. During the ignition process, CH₄ is mainly consumed by H extraction reaction, while N₂O is mainly consumed by decomposition reaction and reaction N₂O + H\stackrel{}{̿}N₂ + OH.

In order to explore the impact of organic Rankine cycle (ORC) on the environment and further improve the research on the impact of ORC on the environment, the environmental analysis of biomass double-stage evaporation double reheat organic Rankine cycle (DEDR-ORC) system was carried out based on conventional exergy environmental method, advanced exergy environmental method and enhanced exergy environmental method, and the results were compared and analyzed using five evaluation indicators. The research results show that the conventional exergy environment method and the advanced exergy environment method have different improvement potentials for the components. The improvement order of boilers obtained by enhanced exergy environmental method has changed from the fourth to the third compared with the advanced exergy environmental method. The total avoidable environmental impact of biomass boilers has increased by 22.370 \mathrm{P}\mathrm{t}\mathrm{s}/\mathrm{h} compared with the analysis results of advanced exergy environmental method. The results of other components and advanced exergy environmental method are not much different, indicating that the impact of biomass DEDR-ORC system on the environment mainly comes from the exergy loss of components and the impact of pollutants discharged by the system on the environment. The research results can provide theoretical support and technical reference for environmental analysis in the field of ORC.

Pulverized coal pre-pyrolysis combustion method is an effective way to reduce NO _x and stabilize combustion. To investigate the pre-pyrolysis combustion characteristics of pulverized coal, the RPM-MSRM model (random pore model-multiphase surface reaction model) for pulverized coal pre-pyrolysis combustion was established, and the effects of air coefficient on generation of pyrolysis gases and conversion of fuel nitrogen were investigated. The results show that after pulverized coal pre-pyrolysis, the volatile matter is pyrolyzed and part of the coke is gasified to generate a large amount of pyrolysis gas [23%—38%(vol)] and high-temperature coke (>800℃), and the flue gas jet rigidity is enhanced, which helps to improve the combustion stability. The rigidity of the flue gas jet is enhanced, which helps to improve the combustion stability. The air coefficient is the main factor affecting the characteristics of pulverized coal pre-pyrolysis. The air coefficient is positively correlated with outlet temperature and negatively correlated with pyrolysis gas concentration. The optimum pre-pyrolysis air coefficient for the device in this paper is 0.3. The lowest NO _x concentration at the unit outlet is 26.82 mg/m³ (@6%O₂,standard operating conditions), and the highest reduction efficiency of fuel nitrogen is 99.51%. Therefore, pulverized coal pre-pyrolysis combustion should be maintained at the optimum air coefficient conditions to achieve the best nitrogen reduction.

In order to solve the problems of fossil energy depletion and environmental pollution, solid oxide fuel cells (SOFC) have been rapidly developed as efficient energy conversion equipment. A multiphysics coupling model of a planar SOFC was established using COMSOL software, which comprehensively considers the interactions among electrical, thermal, flow, and mass transfer fields to study the local transient response characteristics of the SOFC under varying conditions of output voltage, air flow rate, and fuel flow rate. The results show that when the output voltage was set at 0.5, 0.6, and 0.8 V, and fuel flow rate suddenly dropped to zero, the power density changed by -67%, -60%, and -56%, respectively. The average temperature changes and trends in the functional layers of the cell showed significant differences. The impact of fuel flow rate on cell performance was notably greater than that of changes in air flow rate. Due to the direct involvement of electrochemical reactions in the cell and rapid reactions at the electrode surfaces, the power density responded most quickly to changes in output voltage. This study provides important theoretical foundations and technical support for the optimization design of SOFC.

The hot water tank in the solar heating system solves the problem of intermittent solar radiation and does not match the heat load. However, severe thermal stratification and mixing of hot and cold water in conventional thermal storage tanks hinder their ability to provide high-quality hot water, limiting the widespread deployment of solar heating systems. To enhance the thermal storage performance of these tanks, a mathematical model for the thermal storage process was established, and three-dimensional numerical simulations were employed to calculate the thermal storage characteristics, using the thickness of the thermocline layer and thermal storage capacity as performance indicators. The thermal storage characteristics of tanks with different configurations were analyzed using parameters such as the Nusselt number and the exergy. The research findings indicate that the original tank design with a bottom-mounted heat exchanger and no vertical pipe experienced the most severe water mixing, while a top-mounted heat exchanger yielded the best stratification effect but had a lower thermal storage capacity. Integrating a bottom-mounted heat exchanger with a vertical pipe significantly improved the stratification and thermal storage capacity of the tank. With this configuration, the tank’s thermal storage capacity increased by 18.87% within 3600 s, and the exergy increased by 1322.14%. The pump flow rate, vertical pipe height, and pipe diameter all influenced the tank’s thermal storage capacity and stratification effect. Optimal overall performance was achieved with a pump flow rate of 0.25 kg/s and a vertical pipe height and diameter of 1300 mm and 100 mm, respectively.

The mechanism of ultrasonic cavitation microjet cleaning for heavy crude oil deposition is unclear. The clean effects of microjet flow on depositions lack quantitative characterization. A simulation model is developed for cleaning heavy depositions using ultrasonic cavitation microjet impact. The cleaning mechanism and rules of ultrasonic cavitation microjets on depositions are investigated through numerical simulations and experiments. The results indicate that the effects of the microjet caused the formation of circular pits on the surface of the depositions. Expansive cracks appear inside the sediment and at the wall adhesion, which promotes the separation of the sediment. After ultrasonic cavitation experiments, non-uniform cavitation pits appeared on the surface of the depositions, with pit diameters following a GEVⅡ distribution. The diameter and depth of pits on the surface of depositions exhibit linear increases with ultrasonic pressure. The effect of ultrasonic pressure on the depth of pits is significantly greater than its impact on the diameter. The ultrasonic power has been increased from 100 W to 300 W, resulting in an elevation of the ultrasonic pressure from 100 kPa to 200 kPa. The experimental findings demonstrate a rise in the average cavitation pit diameter from 6.10 μm to 7.38 μm, and an increase in the average depth from 1.18 μm to 3.46 μm when subjected to duration of 60 s under the ultrasonic cation. Similarly, the diameter of the pit is increased from 9.60 μm to 9.80 μm, the average depth is increased from 1.42 μm to 3.89 μm in the numerical simulation.

A multi-component catalytic oxidation system was developed for organic contaminated sites soil in this study. In the system, sodium persulfate and hydrogen peroxide were used as the oxidant, Fe²⁺and Cu²⁺ were used as transition metal catalyst, meanwhile, ascorbic acid was used as the complexing agent, forming the homogeneous liquid catalytic oxidation repair reagent. The developed remediation regent was performed in UV light treatment under 50℃ to constitute a three-component activation system including UV light, transition metal ion and thermal activation. The addition of Cu²⁺ effectively promoted the reduction from Fe³⁺ to Fe²⁺. And the addition of ascorbic acid effectively regulate the continuous activation of Fe²⁺. In this oxidation system, the degradation of organic pollutants mainly relies on active free radicals \mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{·-} and HO·. The developed technology was applied to the soil remediation of high-concentration organic contaminated plots. After 30 days of remediation, the removal rates of OPs, PAHs, and BTEX in the soil were 85.0%, 60.5%, and 73.0%, respectively. The efficient removal of organic pollutants in the soil was achieved, providing the basis for the safety development of complex contaminated sites and the improvement of land resources in our country.

Aromatic disulfides have attracted much attention as a new type of LED photoinitiator in recent years. However, the reported aromatic disulfide photoinitiators have a short absorption wavelength and cannot be used in photopolymerization systems triggered by long-wavelength LED light sources with stronger penetration. Therefore, a cinnamyl formamide disulfide photoinitiator (O-BSCF) with long absorption wavelength was designed and synthesized, and its light absorption, photodegradation, and photoinitiating property were investigated in detail. The research results indicated that O-BSCF exhibited a maximum absorption wavelength at 217 nm, with significant light absorption also observed at 405 nm and 455 nm. O-BSCF efficiently initiated the photopolymerization of the Bis-GMA/TEGDMA system under 405 nm and 455 nm LED irradiation. After 200 s of 405 nm and 455 nm LED exposure, final double bond conversion rate of the Bis-GMA/TEGDMA system initiated by O-BSCF achieved 85.2% and 72.5%, respectively, with maximum double bond polymerization rates of 3.05%/s and 1.69%/s, surpassing those of the control group initiated by CQ/DMAEMA. The degradation mechanism of O-BSCF involves S—S bond cleavage under light irradiation, generating arylthiyl radicals that can initiate the photopolymerization of acrylate monomers. Moreover, O-BSCF demonstrated excellent photobleaching performance, suggesting its significant potential for applications in colorless and deep LED curing fields.

To enhance the phase change heat storage properties of stearic acid (SA), boron nitride (BN), carbonized loofah sponge fragments (CLSF), and BN-CLSF mixtures were added into SA to prepare composite phase change materials. The effect of the different additives on the phase change heat storage properties of stearic acid was investigated. The results show that when the mass fraction of BN-CLSF is 2.5%, the thermal conductivity of the composite material can be increased by 16.4% at most, and the corresponding latent heat of fusion is 153.04 J·g^-1. The composites present a maximum reduction of 72.3% in melting time and 33.3% in solidification time compared to pure SA. The temperature of the composite SA/CLSF is increased by 11.14℃ compared to that of pure SA after 550 s of light exposure, which indicates that the addition of CLSF enhances the photothermal conversion capability of the composites. The obtained carbonized loofah sponge fragments/stearic acidcomposites in this study show good thermophysical properties and photothermal conversion capabilities, which attribute to wide potential applications in the application of solar thermal utilization, building energy conservation, and industrial waste heat recovery.

To solve the problem of phosphate tailings accumulation, this study uses phosphate tailings and low-grade phosphate rock as the main raw materials, B₂O₃, Al₂O₃, KCl and other additives, to activate phosphate tailings and low-grade phosphate ore through thermal processing and prepare glass fertilizer. The influence of K-B-Al system on the melting characteristics of phosphorus tailings system was investigated by single factor and response surface experiments. The influence of additives on the activation effect of elements and slag phase structure of molten products was discussed by combining X-ray diffraction (XRD), Fourier infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that when the ratio of phosphorus tailings, low-grade phosphate rock, serpentine, KCl, B₂O₃ and Al₂O₃ is 55∶25∶20∶7∶10∶1.5, the lowest melt flow temperature T_F of the system is 1135℃, which is 335℃ lower than that of the conventional system. The activation rates of P₂O₅, CaO, and MgO in the glass fertilizer melted at 1350℃ are all about 95%. The effects of melting temperature and additives on the glass network structure of the material are analyzed. Under the selected process conditions, B₂O₃ mainly breaks the silicon oxygen network, while Al₂O₃ participates in the network composition and also destroys the silicon oxygen network.

This study presents the design and construction of an experimental device for the preparation of micro/nanoparticles through a spray flash evaporation. Solutions containing organic solutes are sprayed into a vacuum flash evaporation chamber to obtain the organic micro/nanoparticles. The experiment included an initial pressure of 3.0—4.5 MPa, an initial temperature of 130—200℃, three sets of nozzles with different diameters, and four sets of organic solutes. Using the 0.10 mm nozzle, the particle size distribution of p-toluene sulfonamide ranges from 0 to 30 μm. When the initial conditions are increased to 4.5 MPa and 170℃, the proportion of particles smaller than 6 μm can be increased to 62% and 75%, respectively. This indicates that increasing the initial conditions has a significant refinement effect on the particles. In addition, increasing the nozzle size will further increase the particle size and non-uniformity due to the suppression of flash evaporation caused by the deterioration of atomization effect. Therefore, the small diameter nozzle can produce smaller, more concentrated, and uniformly distributed micro/nanoparticles. The particle morphology and size of different organic solutes are different, but the particle size is distributed within 40 μm, indicating that this experimental device has a certain universality.

Inorganic perovskites have attracted a lot of attention due to their excellent optical and thermal stability, but high-efficiency inorganic perovskite solar cells often need to be modified with organic materials, which limits the improvement of device stability to a certain extent. In order to effectively solve this problem, a phase heterojunction (PHJ) strategy was proposed to modify interface inorganic perovskite solar cells (IPSCs) with high efficiency. The PHJ was constructed between the upper interface of the optical absorption layer and the hole transport layer of the inorganic perovskite by spinning methanol solution and evaporating cesium iodide (CsI). Effective management of interface defects is achieved, non-radiative recombination is reduced, and carrier driving and separation are facilitated. Finally, N-I-P IPSCs based on the PHJ strategy achieved a photoelectric conversion efficiency of 20.56%, much higher than the 18.03% of the reference group, and retained 86.14% of their initial efficiency when placed in 65℃ nitrogen (N₂) atmosphere for 1000 h.

Developing electrolytes with high ionic conductivity is crucial to improve the electrochemical performance of semiconductor ion fuel cells (SIFC) at medium and low temperatures. In this study, a solvothermal method was employed to synthesize a core-shell structured CeO₂@La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (CeO₂@LSCF) composite electrolyte material. The phase information, microstructure, and valence state evolution of the material were analyzed. Moreover, its electrochemical performance and fuel cell properties were systematically investigated when used as an electrolyte in SIFCs. The charge transfer mechanism and the role of the built-in electric field at the core-shell heterojunction interface were also examined. The experimental results demonstrated that at 550℃, the CeO₂@LSCF electrolyte exhibited a maximum power density of 942.2 mW·cm^-2 at an open circuit voltage of 1.08 V. As a mixed ion and electron conductor in SIFC electrolyte materials, the core-shell structured CeO₂@LSCF holds great potential for future applications.

Mn₃O₄ is prepared by one-step oxidation. The effects of temperature, rotation speed, ammonia-manganesemolar ratio and ammonia flow rate the structure, morphology and particle size of Mn₃O₄ are studied. The results show that the increase of temperature will accelerate the reaction rate, reduce the super saturation of the system, and increase the particle size of the product. As the rotation speed increases, the shear force caused by the high-speed flow of the solution will make the particle size of Mn₃O₄ tend to decrease and the distribution more concentrated. The increase of the molar ratio of ammonia to manganese will directly reduce the supersaturation of the system and optimize the growth of the crystal, so that the particle size of Mn₃O₄ increases and the sphericity is better. Among them, the Mn₃O₄ particle size D₅₀ obtained under the condition of the mixing speed of 900 r/min, molar ratio of ammonia to manganese is 2.0 and the temperature is 70℃, the D₅₀ is 10.3 μm, the vibration density is as high as 2.65 g/cm³, and the surface area is only 0.369 m²/g. Based on this condition, the process of further regulating the particle size is explored. The particle size D₅₀ of Mn₃O₄ is further reduced to 5.34 μm by reducing the flow rate of ammonia in the early stage of the reaction and increasing the flow rate of ammonia in the later stage of the reaction, while ensuring a high tap density of 2.51 g/cm³ and a low specific surface area of 0.40 m²/g. The LiMn₂O₄ cathode material is prepared by using Mn₃O₄ with particle size of 10 μm and 5 μm mixed with Li₂CO₃. The results show that the sample with 10 μm has better cyclic performance. The discharge specific capacity reaches 121.3 mAh/g at the rate of 1 C, and the capacity retention is 92.8% after 200 cycles. The 5 μm sample has better rate performance, and the specific capacities at 3 C, 5 C, and 10 C are 102.6, 93.4, and 77.6 mAh/g, respectively.