This paper analyzes the development status of key components of mainstream low-temperature electrolytic water hydrogen production technology in China, alkaline water electrolysis (AWE) and proton exchange membrane water electrolysis (PEMWE), and conducts a comparative analysis of the key indicators of two technologies. AWE hydrogen production is more mature and has a higher degree of commercialization, with no significant technical barriers. However, its adaptability to new energy is still not as good as that of PEMWE hydrogen production. To maintain market competitiveness, it is necessary to continuously optimize technology through strategies such as reducing energy consumption and improving electrolysis efficiency and current density. PEMWE hydrogen production is at the initial stage of industrialization and is a more suitable off-grid hydrogen production technology route. The domestic production rate of PEMWE equipment is close to 80%, and the path to technological innovation and large-scale commercial development lies in improving the performance of core materials, increasing domestic production rates, and extending the lifespan of components. In addition, there is a lack of testing technology and evaluation standards for electrolytic cells and key elements in the industry. Therefore, there is an urgent need to develop relevant test technologies and improve evaluation standards simultaneously. The comparative analysis of key indicators reveals that AWE's hydrogen production cost is lower than PEMWE's, and AWE has broad development space in the short term. PEMWE, being a more advanced technology, generally offers higher current density and hydrogen purity than AWE, making it more compatible with renewable energy power generation. Overall, hydrogen production by PEMWE and AWE will be an important way to consume renewable energy to produce green hydrogen.

With the rapid emergence of artificial intelligence, 5G communication, and cloud computing industries, the computational demands of data centers have been steadily escalating, thereby greatly amplifying cooling energy consumption. Nevertheless, traditional air cooling techniques have become inadequate to cope with the increasing heat dissipation needs of data centers. Consequently, liquid cooling techniques, offering superior cooling efficiency, have emerged as the preferred option for chip thermal management over the past decade. This review discusses the recent research progress of several mainstream liquid cooling techniques, including cold plate, immersion, spray, heat pipe, and jet impingement cooling, and comprehensively analyzes their respective pros and cons as well as energy-saving effects in practical applications. Current research indicates that while the cold plate liquid cooling technique enjoys widespread application, it suffers from uneven flow distribution issues; immersion liquid cooling harbors significant energy-saving potential but necessitates addressing challenges related to sealing and reliability. Meanwhile, spray cooling and jet impingement liquid cooling technologies, owing to reliability concerns, witness limited application and require further optimization, particularly in enhancing heat pipe structures. Lastly, in conjunction with the prevailing research status, this review anticipates the potential for improvements in the cooling performance and reliability aspects of liquid cooling techniques.

It is the development trend of marine renewable energy research to make full use of offshore floating platforms, develop wave energy, wind energy, and solar energy, and realize comprehensive utilization of marine renewable energy through multi-energy complementarity. Domestic and international scholars have conducted research in the field of integrated utilization of offshore renewable energy. They have developed various joint plants, including wave-wind, wave-photovoltaic, and wind-photovoltaic, as well as other related technologies, yielding some promising results. Given the typical characteristics of renewable energy, such as intermittence, randomness, and volatility, wave power, wind power, and photovoltaic power all exhibit these traits. However, the complementary relationship among these energy sources and the current status of multi-energy complementary integration platform technology have not been comprehensively discussed. This paper examines the current research status, introduces the characteristics of floating offshore wave power, wind power, and photovoltaic power, and investigates the spatial and temporal relationship between these three marine energy sources at the same location. The findings of this study can provide insights and reference for the overall planning, detailed design, modeling, research, and construction of integrated platforms for wind power, photovoltaic power, and wave energy generation, as well as their coordination and control through multi-energy complementarity.

This study investigates the phosphorus/carbon/lithium composite materials as a novel anode material for solid-state lithium batteries prepared using high-energy ball milling combined with pre-lithiation. Phosphorus has a high theoretical specific capacity, graphite has good chemical stability and interface compatibility, and lithium metal has excellent mechanical properties and high theoretical specific capacity, making the combination of the three materials can take into account their respective characteristics and have a synergistic effect. When the phosphorus-to-carbon mass ratio is 2:8 and the pre-lithiation level is 10%, a lithium iron phosphate (LiFePO₄) | lithium lanthanum zirconium tantalum oxide/polyvinylidene fluoride-hexafluoropropylene copolymer composite solid electrolyte (LLZTO/PVDF-HFP) | phosphorus/carbon/lithium composite anode (P/C28-10%) solid-state battery is constructed. The battery exhibits a capacity retention of 107.6 mA⋅h/g and a capacity retention rate of 80.5% after 100 charge-discharge cycles at 25 °C and 1.0 C. The P/C28-10% | LLZTO/PVDF-HFP | P/C28-10% cell can operate steadily for over 200 hours. Furthermore, the discharge potential plateau of P/C28-10% composite anode is much higher than that of metallic lithium electrochemical potential, reducing the generation of lithium dendrites. This study opens up a new avenue for the negative electrode of solid-state batteries, which can serve as a reference for developing solid-state batteries with high-energy density, high-safety, and large-scale storage.

The mechanical properties of submarine hydrate-bearing sediments are crucial for the safe exploitation of hydrate resources. A series of consolidated drained triaxial compression tests was conducted to systematically investigate the mechanical behavior of methane hydrate-bearing fine sand specimens prepared using the frost-seeding and excess-gas methods under gas/water saturated conditions. The results show that specimens prepared by the excess-gas method exhibited higher shear strength and stiffness under gas-saturated conditions, along with more pronounced strain-softening and dilative behavior compared to those from the frost-seeding method. The strain-softening behavior is jointly governed by hydrate saturation and confining net stress. After water saturation, the hydrate pore habit transitioned to a non-cementing type, resulting in significant alterations to the stress-strain curves. For specimens prepared by the frost-seeding method, the shear strength increased linearly with hydrate saturation. Under gas-saturated conditions, the magnitude of shear strength increase diminished as the confining net stress rose; however, in the water-saturated system, the strength increase was independent of the confining net stress. The strength degradation induced by the change in saturation state is primarily attributed to a decrease in cohesion. The combined frost-seeding and water saturation technique provides an effective approach for reconstructing non-cemented hydrate-bearing sediment specimens, offering critical support for investigating their mechanical properties and advancing resource development.

Biomass resources, being carbon-neutral, serve as an excellent energy fuel. Traditional methods of biomass gasification to produce syngas involve the water-gas shift reaction, followed by separation and purification processes to achieve high concentrations of syngas and hydrogen. However, these processes are intricate and complex. The chemical looping gasification and reforming of biomass for hydrogen production represent a novel technology in syngas and hydrogen preparation. Based on Aspen Plus software, hydrogen production from biomass chemical looping gasification reforming was studied, using pine biomass and steam as feedstock, and syngas and hydrogen as final products, combining process simulation and sensitivity analysis to explore the influence of key parameters on system performance and obtain maximum hydrogen/synthesis gas yield. Based on the Gibbs reactor, we simulated the product fractions and state parameters of the reactants in the fuel reactor, hydrogen reactor, and air reactor of the biomass chemical looping gasification reforming process for hydrogen production under the conditions of satisfying phase equilibrium and chemical equilibrium. Through the sensitivity analysis and thermodynamic analysis of the key parameters, the optimal operating conditions and operating parameters were determined as follows: fuel reactor temperature of 800 °C, oxygen carrier to biomass ratio of 0.4, water vapor (steam) to biomass ratio of 1.36, hydrogen production reactor temperature of 600 °C, air to biomass ratio of 0.57. The syngas gas yield is 0.98 m³/kg, the H₂ yield is 0.025 kg/kg, and the system's exergy efficiency is 68.06%. Based on the simulation analysis, it is demonstrated that the biomass chemical looping gasification reforming system for hydrogen production not only obtains higher yield syngas and high-purity hydrogen, but also realizes the system self-heating. The constructed biomass chemical looping gasification reforming hydrogen production system will provide the necessary basis and information for the optimized design of the key technologies of the subsequent processes and the larger-scale engineering demonstration.

A V₂O₃@C/S composite cathode material is successfully synthesized using a combination method of solution-based, hydrothermal, and high-temperature carbonization techniques. The resulted composite cathode is employed with a BN/PVDF-HFP composite solid-state electrolyte to assemble a high-performance lithium-sulfur (Li-S) battery. The V₂O₃@C composite exhibits excellent structural stability, high conductivity, good sulfur adsorption, and catalytic activity. The V₂O₃@C/S cathode-based Li-S cells exhibit higher initial specific capacity, rate performance, and cycle stability compared to the conventional C/S cathode. At a 0.1 C rate, the V₂O₃@C/S cathode delivers an initial specific capacity of 1 125 mA∙h/g, with a capacity retention of 67.1% after 150 cycles. At a 0.5 C rate, the capacity retention after 250 cycles is 45.5%. Cyclic voltammetry, impedance spectroscopy, and Tafel analysis confirm the superior performance of the V₂O₃@C/S cathode for enhancing reaction kinetics and reducing charge transfer resistance. This work provides an effective strategy for designing high-performance cathodes of lithium-sulfur batteries.

The power industry has great potential for energy conservation and carbon reduction in the Guangdong-Hong Kong-Macao Greater Bay Area and Guangdong province. Based on the electricity consumption data from 2010 to 2022 in Guangdong province, a grey model modified by the Markov method was developed to predict its electricity consumption before 2030. Using electricity balance as the constraint condition, the comparative analysis of electricity supply structure, coal consumption for coal-fired power, and its carbon dioxide emission was conducted under three scenarios: the baseline scenario, the new energy power development scenario, and the exceeded development scenario of new energy power. The results show that the grey model modified by the Markov method improves the prediction accuracy. The projected electricity consumption in Guangdong province is estimated to be 941 billion kW⋅h in 2025 and 1 246.8 billion kW⋅h in 2030. Under the new energy power development scenario, the electricity generation capacity from new energy power like photovoltaic and wind power will be 428.1 billion kW⋅h in 2025 and 548.4 billion kW⋅h in 2030. While under the exceeded development scenario of new energy power, it is expected to increase to 585.1 billion kW⋅h in 2025 and 748.4 billion kW⋅h in 2030, respectively. Compared with the baseline scenario, the development of new energy power is estimated to reduce coal demand for coal-fired power by 18 million tons in 2025 and 50 million tons in 2030, of which coal-fired power's carbon dioxide emissions can be subsequently reduced by 49 million tons in 2025 and 134 million tons in 2030.

The utilization of biogas is a key link in China's future sustainable energy development, and its combustion efficiency is directly related to the concentration of CH₄, so it needs to be pre-treated for purification before the utilization of biogas. Hydrate-based gas separation technology offers advantages such as environmental friendliness, simple operation, high separation efficiency, and excellent selectivity, making it a highly promising gas separation technique. Molecular dynamics simulations were employed to investigate the growth of hydrates formed from ternary mixtures of biogas components (CH₄/CO₂/N₂), exploring the principles governing changes in hydrate growth rates. It provides additional data support and a theoretical basis for applying hydrate-based gas capture technology in biogas purification. Results indicate that the hydrate growth rate is fastest at a molar ratio of CH₄/CO₂/N₂ = 14:5:1, while it is slowest at 1:1:1. Stagnation and high-probability growth failure occur during hydrate formation at the latter ratio, suggesting that equimolar mixtures are unfavorable for hydrate growth. Across different ternary systems, hydrate growth rates exhibited non-uniform patterns with frequent fluctuations. Growth rates correlated with cage-like structures: regions dominated by 5¹²6² cages accelerated hydrate formation significantly, while those dominated by 5¹² cages slowed it down.

Energy piles enable the access and usage of shallow geothermal energy and have the advantages of high heat exchange efficiency, reduced space occupation, and a lower investment cost when compared to the standard horizontal/ borehole buried pipe system. This study discusses the origins of energy pile technology, contemporary research development, and application status at home and abroad based on the kind of pile carrier, heat exchanger buried pipe classification, and soil foundation environment differences. The thermal utilization method of the solar photovoltaic module based on energy pile technology is proposed. The working principle of the new system is briefly introduced, demonstrating the advantages of the joint operation of energy piles and photovoltaic module. This provides references and ideas for the complementary advantages and coupling utilization of two clean energy sources of solar energy and geothermal energy.

The byproduct of alkali lignin from papermaking has a high yield but poses a significant environmental threat. Conventional thermal treatment faces challenges due to alkali metal bottlenecks. Chemical looping gasification presents a vital avenue for resource utilization. In this study, NiFe₂O₄/ZrO₂ was employed as an oxygen carrier, and the reaction characteristics of alkali lignin chemical looping gasification were investigated using a fixed-bed reactor combined with various analytical methods. Thermogravimetric analysis revealed that the decomposition of lignin/alkali lignin primarily occurred between 200-600 ℃. With increasing heating rates, the overall thermogravimetric curve shifted towards higher temperatures, with a maximum decomposition rate of 0.31%/min observed at a heating rate of 20 ℃/min. X-ray diffraction analysis indicated that the inert oxygen carrier ZrO₂ did not participate in the reaction, while the transformation path of the active oxygen carrier was NiFe₂O₄→Fe_0.64Ni_0.36→NiFe₂O₄. Based on fixed-bed alkali lignin chemical looping gasification studies, high temperatures facilitated the decomposition process, with a carbon conversion rate of 31.45% observed at 950 ℃. The lattice oxygen in the oxygen carrier promoted the shift of reaction equilibrium to the right. When the alkali lignin-to-oxygen carrier ratio was 1:9, the highest carbon conversion rate of 45.37% was achieved. Additionally, an increase in the oxygen carrier initially led to an increase in CO production followed by a decrease, while CO₂ production showed an increasing trend, indicating that excessive oxygen carriers promoted the conversion of CO to CO₂. A moderate amount of alkali metal facilitated lignin carbon conversion and syngas generation while inhibiting CO₂ production.

To alleviate the increasingly serious energy crisis and improve the utilization efficiency of biomass resources, gasification, as an important means of thermochemical conversion technology, is considered to be a hydrogen production technology from biomass with great potential. This paper summarizes the principle of biomass gasification, describes the chemical reaction mechanism in the process, discusses the effects of gasification agent, temperature, pressure and catalyst types on the green hydrogen production process, comprehensively analyzes the existing problems and improvement methods in the hydrogen production technology from biomass gasification. The ideas for the source and preparation technology of green hydrogen are provided.

The global energy crisis is progressively escalating, accompanied by the growing severity of the climate change challenge. Meanwhile, China finds itself in a phase of rapid development, making it imperative to address the pressing issues of energy supply and demand, energy consumption, and the deteriorating ecological environment. The development and utilization of biomass resources can not only solve the environmental and climate problems of global warming caused by greenhouse gas emissions, but also be one of the important ways to solve the problem of energy shortage in China. As a high-quality biomass resource, energy crops have the advantages of low environmental requirements for carbon sequestration, large amounts of carbon sequestration, and high carbon sequestration efficiency. Based on the importance of the development and utilization of energy crops, this paper summarizes the types, characteristics and research status of energy crops at home and abroad, puts forward the needs of cultivation, land selection, collection, storage, transportation, and clean transformation in the process of development and utilization of energy crops. It also points out that the cultivation and utilization of energy crops have broad strategic application prospects in revitalizing rural energy supply and implementing the dual carbon goals. Looking forward to the future, green finance's support for the priority trading of biomass emission reductions in the carbon market is the key to the sustainable development of energy crops.

Under the strategic background of carbon peaking and carbon neutralization, biomass-derived carbon materials prepared from biomass as carbon sources are one of the most important ways to utilize biomass for resourcefulness, high value, and carbon reduction. Carbon derived from biomass is known as "black gold" and has broad application prospects in adsorption and purification, catalysis, and energy storage. Biomass-derived carbon's structural properties and applications are closely related to the raw materials, preparation, and modification methods. Based on the composition and structure of biomass-derived carbon, the commonly used preparation methods such as pyrolytic carbonization, hydrothermal carbonization, activated carbonization, and template method were introduced systematically in this paper. To improve the inherent defects of the original biomass-derived carbon to meet its needs in specific applications, acid-base modification, heteroatom doping modification, metal salt, and its oxide modification were summarized in terms of enhancing the performance of the biomass-derived carbon. Finally, the application of machine learning in predicting and regulating biomass-derived carbon was introduced, and the future research focus and development prospects were prospected, which can provide a reference for the development of the preparation and application of biomass-derived carbon materials.

Supercapacitors are considered to be one of the most ideal energy storage devices for their advantages of fast charging and discharging, good stability and long lifetime. Biomass-derived carbon with a certain pore structure and electrical conductivity is suitable as supercapacitor electrode material. The development of biomass-based supercapacitor carbon materials is an important way to achieve high-value-added use of biomass energy and energy sustainability. Based on the storage principle, supercapacitors are classified into electric double-layer capacitors and pseudocapacitors. Firstly, the preparation strategies of biomass-derived carbon as electrodes for electric double-layer supercapacitors are introduced from aspects such as biomass selection and pretreatment methods, with a focus on the carbonization methods, activation means of biomass and their pore-forming principles. Subsequently, the surface modification means of carbon materials are described, focusing on the advantages of coupling biocarbon and pseudocapacitor electrode materials to form a composite material as well as the preparation method. Finally, the challenges and future perspectives of preparing supercapacitor carbon materials from biomass are presented in the light of current research.

With the proposal of the strategy of building a maritime power and the dual carbon goals, the development of marine resources has become the core of China's scientific and technological development. Wave energy resource assessment is a method for gaining a deeper understanding of marine resources. The application scenarios of wave energy resource assessment were analyzed from three aspects: site planning and selection, feasibility studies, and design and development. The development status of the four methods for wave energy resource assessment was presented in chronological order. The current situation of wave energy resource assessment at home and abroad was discussed, and the sea areas where assessments have been carried out in China were statistically analyzed. Finally, through summary and comparative analysis, the differences in the assessment of wave energy resources are revealed in the performance evaluation of wave energy power generation systems. The research results can provide a reference and guidance for the development and utilization of wave energy, and contribute to China's marine construction.

Solid acids represent an important class of heterogeneous catalysts and play a key role in biomass conversion processes. Compared to liquid acid catalysts, solid acids exhibit distinct advantages, including ease of separation and regeneration, high temperature tolerance, and environmental friendliness. However, industrial applications have mainly been hindered by issues such as poor hydrothermal stability and limited recyclability. This review systematically summarized design strategies and research progress in enhancing the hydrothermal stability of solid acids, focusing on three representative systems: metal oxides improve erosion resistance by constructing stable crystal phases and carbon coatings; zeolites enhance structural stability through adjustment of the silicon-to-aluminum ratio and composite modification; carbon-based solid acids stabilize acid sites via porous structure optimization, introduction of hydrophobic components, and novel sulfonation techniques. The research results will provide theoretical guidance for the design and development of high-performance solid acid catalysts.

To study the heat transfer performance of the coaxial casing heat exchanger in the medium and deep layers, considering the soil temperature gradient, geological stratification, and groundwater seepage simultaneously, an analytical and layered model was proposed to resolve the temperature response between the layers around the borehole and the fluid in the annular cavity. The results show that the temperature curve obtained by the layered model in the depth direction is closer to physical reality compared with the homogeneous model. The homogeneous model will underestimate the outlet temperature of geothermal wells, whether the seepage effect is considered or not. The maximum deviation in the predicted radial temperature of the outer casing wall caused by considering seepage is 0.40 °C. When the seepage layer is located 2 000 meters underground, the critical seepage velocity of heat conduction between the stratum and the pipe wall is 5 × 10⁻⁷ m/s, while the heat exchange between the stratum and the pipe wall is mainly carried out by thermal convection when the seepage velocity is greater than 1 × 10⁻⁵ m/s. Heat exchange between the formation and the pipe wall primarily occurs through thermal convection. Compared to the scenario without seepage flow, the local heat transfer rate of the annular fluid has increased by 56.7%. The vertical permeability of the seepage layer leads to an increase in the thermal conductivity of the region outside the boundary, thereby increasing the outlet temperature of the geothermal well. For the same heat extraction, considering the seepage effect can reduce the buried depth of the geothermal well.

The present study centers on a single-row burner for domestic gas water heaters, utilizing experimental approaches to investigate the effects of varying equivalence ratios (φ) and hydrogen blending ratios (γ) on the flame characteristics of the burner. Employing planar laser-induced fluorescence, the morphological features of the flame and the distribution of OH radicals under different φ and γ conditions were captured. A mobile thermocouple was utilized to probe the temperature field distribution under various experimental scenarios. The findings indicate that the equivalence ratio significantly influences the morphological characteristics of the flame and the distribution of OH radicals within it. As φ decreases, there is a drastic shortening of the flame height; when φ reaches 1.25, the flame becomes closely attached to the burner's outlet orifice surface, with the flame front exhibiting fine serrations influenced by the orifice structure. Under low equivalence ratio (φ = 1.25) conditions, an increase in the hydrogen blending ratio leads to a slight reduction in flame height, accompanied by a marked increase in the concentration of OH radicals in the flame. The flame temperature is primarily influenced by the equivalence ratio. At a hydrogen blending ratio of 20%, the temperature increases sharply near the flame root as the equivalence ratio decreases. In contrast, the temperature remains relatively stable at the flame center, consistently ranging within 1 400 ± 200 ℃. The research findings can provide reference for the design of gas mixing process parameters and burner structures for hydrogen-blended gas water heaters.

In recent years, lithium battery energy storage has been widely used as an important energy storage technology, but it needs to be equipped with a good thermal management system to control the temperature of lithium batteries to make them operate safely and stably. An air-cooled lithium battery thermal management system coupled with an inclined U-shaped micro heat pipe array was proposed in this study, and compared with the module without an inclined U-shaped micro heat pipe array, its heat dissipation performance under different ambient temperatures, different air volumes, and different charge-discharge rates was studied. The results show that when the ambient temperature is 25 °C and the charge-discharge rate is 1 C, the maximum temperature rise of the battery module coupled with an inclined U-shaped micro heat pipe array is reduced by up to 33.3%, and the maximum temperature difference of the single cell and the battery module is reduced by up to 65.8% and 35.8% compared with the module without an inclined U-shaped micro heat pipe array. Even under a 2 C charge-discharge rate, the maximum temperature of the battery module can be controlled at about 40 °C, and the maximum temperature difference of the single cell and the battery module is 1.59 °C and 2.46 °C, respectively.

To investigate the efficiency and energy recovery potential of thermophilic anaerobic membrane bioreactor (ThAnMBR) in treating various types of organic wastes, the effectiveness of ThAnMBR in the treatment of alcohol distillation wastewater, food wastewater, sludge, paper wastewater, and livestock waste was evaluated, and the energy efficiency difference between thermophilic and mesophilic treatment. The ThAnMBR perform excellently in terms of chemical oxygen demand (COD) removal rate and methane production, achieving over 90% COD removal efficiency and high biogas production rates. Furthermore, the system demonstrates the potential for energy self-sufficiency, contributing to the sustainable development of wastewater treatment. This study provides references for the development of ThAnMBR in China, and highlights its potential application value in treating high-temperature wastewater and promoting resource recovery.

MXene, with its excellent electronic conductivity and abundant surface functional groups, has been widely utilized as hosts for lithium metal anodes. However, MXene obtained by etching methods typically exhibits an accordion-like structure, which is not conducive to the uniform deposition of lithium ions and may restrict the exposure of functional groups, resulting in poor lithium affinity. As emerging two-dimensional multifunctional materials, covalent organic frameworks (COFs) possess adjustable chemical properties. The triazinyl COFs (TCOFs) structure with high-density redox-active units can provide more lithium-affinitive sites, effectively compensating for the weak lithium affinity of MXene. The stacking problem of MXene is addressed through intercalation with silane coupling agents, and the exposed functional groups on the intercalated MXene surface are utilized to construct lithiophilic TCOFs, leading to the preparation of a lithiophilic composite electrode (TCOFs@MXene-NH₂) with promising potential applications. The modified anode, TCOFs@MXene-NH₂, exhibits outstanding electrochemical performance, demonstrating stable cycling for over 1 200 h at a high current density of 3.0 mA/cm² in symmetric cell configurations. The LiFePO₄//TCOFs@MXene-NH₂ cells exhibit excellent cyclic stability at 1.0 C, maintaining a specific capacity of 132.8 mA⋅h/g even after 600 cycles (84.2% capacity retention rate). This exceptional electrochemical performance validates the reliability of this concept as host materials in lithium-metal batteries, providing insights for developing thin, conductive networks for high-performance energy storage devices.

To meet the decarbonization needs of the ceramic industry, a study was conducted on the hydrogen-enriched combustion characteristics of a high-power natural gas burner for ceramic kilns. The results indicate that hydrogen blending elongates the two localized high-temperature zones within the prechamber. Furthermore, a higher hydrogen proportion causes the bottom of the lower high-temperature zone to shift closer to the burner head, thus increasing the risk of high-temperature damage to the combustion chamber head. Due to the preferential reaction between H₂ and O₂, the CH₄ conversion rate in the prechamber exhibits a trend of initially decreasing and then increasing with hydrogen enrichment—being suppressed in the initial combustion stage and promoted in the high-temperature combustion stage. Concurrently, hydrogen blending inhibits the conversion of the intermediate combustion product CO, resulting in higher CO concentrations within the prechamber as the hydrogen blending ratio increases. In thermal tests, the burner achieved stable combustion with an efficiency of over 99.9% combustion across hydrogen blending ratios ranging from 0% to 50% by volume. Under constant power output, the maximum increases in kiln heating temperature and exhaust temperature were 28.5 K and 14.2 K, respectively, indicating a minor overall enhancement compared to operation with pure natural gas. When the hydrogen blending ratio was between 0% and 30%, the increase in NO_x emissions at the kiln exit ranged from 6% to 9%. However, as the hydrogen blending ratio increased from 30% to 50%, NO_x emissions rose sharply by up to 21%. The study demonstrates that hydrogen blending ratios of 0% to 50% can meet the heating temperature requirements of ceramic kilns when using this high-power natural gas burner. Nevertheless, excessive hydrogen blending exacerbates the risk of high-temperature damage to both the burner head and the prechamber head, while also leading to a dramatic increase in NO_x emissions.

Driven by the carbon peaking and carbon neutrality goals, highly efficient and economical energy-storage technologies are urgently required. Supercapacitors have emerged as a current research focus due to their rapid charge-discharge capability, high efficiency, and ultra-long lifespan. Notably, electrode materials directly influence the performance of supercapacitors. Among the precursors selection of electrode materials, lignin stands out owing to its unique structural characteristics. However, lignin derived from different plant sources and via distinct separation technologies exhibits variations in chemical composition and microstructure, which may significantly affect its performance as an electrode material for supercapacitors. Currently, there is relatively limited research on the properties of lignin-based electrode materials. Therefore, this paper first introduces the characteristics of lignin-derived porous carbons obtained through different lignin types and pretreatment methods, as well as their applications in supercapacitors. It also summarized the electrochemical properties of lignin-based porous carbons prepared by various methods. Subsequently, the paper outlined the application status of lignin-based porous carbons in pseudocapacitors, employing strategies such as heteroatom doping and the use of conductive polymer composites. Finally, the directions for improving the performance of lignin-based electrode materials and their application prospects in composite electrode materials were prospected.

Lithium manganese iron phosphate (LiMn_xFe_1−xPO₄, LMFP) material has the advantages of high energy density, excellent safety, and low-temperature performance, which is under intensive development in the industry of lithium-ion batteries. However, the intrinsic electronic conductivity and lithium ion diffusion rate of LMFP are low, resulting in poor rate performance. Furthermore, the lattice distortion caused by the Jahn-Teller effect and the dissolution of Mn ions during charging and discharging result in a rapid decay of battery capacity. In this work, a novel organosilicon compound [3-(N, N-dimethylamino) dioxypropyl] pentamethyldisiloxane (DSON) electrolyte-added cathode film-forming additive was designed and synthesized to suppress the Jahn-Teller effect and improve the electrochemical performance of LMFP batteries. It was found that DSON could form a uniform and stable cathode electrolyte interfacial film, effectively inhibiting the side reaction between the cathode material and the electrolyte, and significantly improve the electrochemical performance at both room and high temperatures. At 25 °C, compared with the LMFP/Li cell using a base electrolyte, the capacity retention of the LMFP/Li cell with 0.2% DSON electrolyte increases from 81.8% to 85.3% after 200 cycles at 0.5 C. At 55 ^oC, the capacity retention of the cell with DSON electrolyte increased from 69.8% to 83.3% after 200 cycles at 0.5 C.

LiMn₂O₄ batteries have been widely used in the field of power batteries due to their advantages of high safety and low cost, but their cycling stability at high temperature remains a major challenge. A novel amine-functionalized trisiloxane electrolyte additive, [3-(N,N-dimethylamino)diethoxypropyl]heptamethyltrisiloxane (MTSON), is designed and synthesized to enhance the high-temperature performance of LiMn₂O₄ batteries. By using 0.5% MTSON, the capacity retention rate of LiMn₂O₄/Li cell increases to 95.2% after 200 cycles at 55 ℃ and 1 C rate, compared to 92.6% for the base electrolyte. X-ray photoelectron spectroscopy shows that MTSON could construct a stable cathode electrolyte interface film on the surface of the LiMn₂O₄ electrode. At the same time, MTSON additive inhibits the hydrolysis of LiPF₆ salts in the electrolyte, and the dissolution amount of manganese ions in LiMn₂O₄/Li cells is reduced by nearly 80% after 200 cycles at 55 ℃. This work shows that MTSON is a promising electrolyte additive to improve the high-temperature performance of LiMn₂O₄ batteries.

A pressure difference-based method for polymer hydrogen permeation testing is proposed, and an apparatus is developed to elucidate the permeation behavior of hydrogen in polymer pipes. In this apparatus, the high-pressure side tank is used to fill hydrogen and set the test pressure. The permeation side tank is equipped with a hydrogen concentration detection sensor, enabling real-time in-situ monitoring of the hydrogen permeation concentration. Hydrogen permeation tests were conducted on high-density polyethylene (HDPE) and polypropylene (PP) under varying hydrogen pressures ranging from 1 MPa to 4 MPa, and sample thicknesses ranging from 2 mm to 6 mm at ambient temperature. The crystallinity of the HDPE and PP samples was characterized using X-ray diffraction analysis. The results indicate that the steady-state hydrogen permeation rates of HDPE and PP increase with rising hydrogen pressure, yet decrease as thickness increases. The hydrogen permeability coefficients for both materials remain largely consistent at the same thickness across varying pressures. The hydrogen permeability coefficients obtained in this study are of the same order of magnitude as those reported in existing literature. The crystallinity of HDPE is higher than that of PP, resulting in a lower steady-state hydrogen permeation rate. These findings validate the rationality of the testing methodology employed in this study. They can offer valuable technical guidance for the selection and design of non-metallic hydrogen transport pipes and elastomeric seals.

High-solid anaerobic digestion of pig manure offers the advantage of producing minimal liquid digestate. However, the anaerobic decomposition of organic matter can be hindered by potential mass transfer limitations when high-solid pig manure is used. It remains uncertain whether the commonly employed continuously stirring reactor is effective for high-solid pig manure. To address this issue, this study operated 131 d mesophilic continuous anaerobic digestion reactor treating pig manure with a total solid (TS) content of up to 15%, with a hydraulic retention time set at 90 days. The decomposition of organic matter and the reaction kinetics were investigated. The results indicated that the pig manure contained 0.91 g and 1.27 g of chemical oxygen demand (COD) per gram of total solids and volatile solids (VS), respectively. High-solid pig manure was effectively decomposed, yielding methane production of 0.31 L/g, which was very close to the experimental results of methane production potential. Approximately 53% of VS and 55% of COD were decomposed. The total volatile fatty acids concentration remained below 100 mg/L, demonstrating high decomposition efficiency and strong process stability. Material balance analysis revealed that approximately 52% of carbohydrates and 31% of proteins were decomposed. The research results indicate that high concentration pig manure with a TS concentration of 15% can be fermented using a fully mixed fermentation process, which is feasible for industrial application.

It is crucial to develop and utilize sustainable clean energy to achieve the goals of carbon peaking and carbon neutrality. In particular, the utilization of hydrogen fuel cells represents a significant technological approach towards enhancing the cyclical regeneration. With the development of anion exchange membranes and platinum-free catalysts for cathodic oxygen reduction under alkaline conditions, anion exchange membrane fuel cells (AEMFCs) have shown excellent application prospects. Among them, anodic hydrogen oxidation reaction (HOR) emerges as a pivotal constraint on performance, predominantly attributed to the diminished kinetic rates observed in alkaline environments. Ruthenium (Ru) has been regarded as a potential substitute for platinum in fuel cells due to its suitable hydrogen binding energy, oxygen affinity, and relatively low cost. Therefore, elucidating the catalytic mechanism of ruthenium-based catalysts for HOR in alkaline media is of significant importance for the development of highly efficient and stable catalysts. This article first introduces the basic mechanism of electrocatalytic HOR under alkaline conditions. Subsequently, a systematic classification and summary of reasonable design strategies for ruthenium-based HOR catalysts were conducted from the perspective of activity descriptors. Additionally, the practical application of ruthenium-based catalysts in fuel cells was introduced. Finally, prospects were created for the development of low-cost, stable, and efficient synthesis strategies for ruthenium-based HOR catalysts.

To explore the energy-saving effects of spiral flat tubes in ventilation systems, a certain clean laboratory energy recovery device is taken as the research object, with a focus on analyzing the performance characteristics of spiral flat tubes with different long-short axis ratios, including the flow field, heat transfer performance, heat exchange efficiency, resistance, and the performance factor of the energy recovery device. The study employs the numerical simulation method to conduct an in-depth exploration of the of the energy recovery device's performance and validates the model's reliability through real-time test data. The research findings indicate that, compared with the conventional round tubes, the heat transfer coefficient of spiral flat tubes is increased by 1.29 times, the heat exchange efficiency is enhanced by 8.6%, the performance factor is augmented by 1.14 times, effectively improving the energy recovery efficiency. The heat exchange efficiency of the spiral flat tubes energy recovery device in winter and summer reaches 78.5% and 73.2%, respectively, providing some references and more options for the design and optimization of clean laboratory ventilation systems.

Poly(butylene succinate-cobutylene furandicarboxylate) copolyester (PBSF) with different alcohol-acid molar ratios was synthesized by direct esterification using 2,5-furandicarboxylic acid, 1,4-succinic acid, and 1,4-butanediol as raw materials, tetrabutyl titanate as catalyst, and triphenyl phosphite as stabilizer. The structure of polyesters was characterized by nuclear magnetic resonance hydrogen spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction, and the results showed that the feedstock alcohol-acid molar ratios had less influence on the structure and crystalline structure of PBSF. The chain structure of PBSF was mainly dominated by the PBF chain segments that contained a rigid ring. PBSF exhibited typical thermoplastic elastomer characteristics; its glass transition temperature (0.27-6.81 °C) was lower than room temperature. Moreover, PBSF showed good thermal stability, with an initial thermal decomposition temperature higher than 347 °C. The tensile test results indicate that the alcohol-acid molar ratios of the raw material have a large influence on the mechanical properties of PBSF. The Young's modulus, the tensile strength, and the elongation at break decreased and then increased with the alcohol-acid molar ratios of raw material. The best tensile properties of PBSF-2.50 are obtained when the alcohol-acid molar ratio of raw material is 2.50, with tensile strength and the elongation at break of 19.93 MPa and 932.94%, respectively. Therefore, PBSF can be used as thermoplastics, as well as elastomers or impact modifiers.

Power transformers generate significant waste heat during operation. If this part of the waste heat can be recovered and utilized, it will effectively help the realization of the low-carbon operation goal of the power system. A dry-type transformer model is established to explore the feasibility of waste heat utilization of the transformer, and its operating temperature distribution is simulated. First, the influences of wind speed of the cooling fan, ambient temperature, and load rate on temperature distribution of dry-type transformers are discussed and analyzed, respectively. Furthermore, the orthogonal experiment is designed to train the neural network based on the simulation data of the temperature distribution, and a general mathematical model for calculating the temperature distribution of the dry-type transformer is obtained. Last, in the case study, simulation tests are carried out on the two positions related to waste heat utilization. The Bayes-GRU model achieves mean absolute percentage error (MAPE) values of 2.24% and 2.73%, with corresponding R² scores of 0.99 and 0.97, demonstrating significantly enhanced calculation accuracy compared to single neural network models and reflecting superior accuracy and universality. This research can provide the theoretical basis for the engineering application of transformer waste heat utilization.

Ammonia is one of the most important chemical raw materials, an ideal hydrogen storage material, and a carbon-free fuel. Its industrial production mainly relies on the Haber-Bosch process driven by fossil fuels. Given the implementation of carbon peaking and carbon neutrality goals, developing a new low-carbon synthetic ammonia process driven by renewable energy is necessary. Mechanochemical synthesis of ammonia is a mild-condition synthetic ammonia technology that has emerged in recent years and has great potential for development. This article introduces the reported process of mechanochemical synthesis of ammonia, predicts possible process routes by comparing the feasibility of the processes, and makes prospects for future development directions. Hopefully, this paper will provide some reference to understand the current development of mechanochemical ammonia synthesis and conduct further research.

Low air pressure fuel cells can be used for household combined heat and power systems and distributed energy systems. However, the transport of reactant gases and water within the micro-porous layer of low air pressure fuel cells are easily obstructed, leading to large voltage fluctuations and poor output performance. To enhance the gas-liquid transport in the cathode micro-porous layer and improve the power generation performance of fuel cells under a low air pressure condition of 15 kPa, this study established a three-dimensional multiphase fuel cell model. The model analyzed the effects of porosities, thicknesses, multilayer structures, and non-uniform gradient micro-porous layers on the gas-liquid transport and output performance of fuel cells. It also considered the impact of micro-porous layer porosity and thickness on conductivity, and investigated the influence of multi-parameter coupling on output performance. The results show that under a low air pressure condition of 15 kPa, the fuel cell achieves the best performance when the micro-porous layer has a porosity of 60% and a thickness of 60 µm. The use of multilayer and non-uniform gradient structures in the micro-porous layer can enhance mass transport and improve the output performance of fuel cells. The developed model can be used for analysis and prediction in the development of micro-porous layers for low air pressure fuel cells.

Geothermal energy stands out as a promising low-carbon energy source under the dual-carbon goals. In recent years, the rapid development of artificial intelligence (AI) technology has empowered the geothermal industry through its integrated applications, drawing significant attention and having a profound impact. This paper systematically summarizes the latest advancements and achievements of AI technology in various stages of geothermal exploration, development, and utilization. It is observed that AI technology is gradually extending its applications to various technical directions within the geothermal industry. With the continuous evolution of new-generation AI technologies, the integration of AI and geothermal energy will accelerate further, promoting the development and utilization of geothermal resources towards real-time allocation, dynamic adjustment, and multi-system collaboration. It is anticipated that within 8-10 years, an integrated intelligent complex encompassing geothermal exploration, development, and utilization will be established, forming a closed-loop intelligent system for the entire industry chain of geothermal energy. This will lead to a new pattern of complementary and synergistic development and efficient utilization of geothermal and multiple energy sources.

As a downhole heat exchanger (DHE), super-long gravity heat pipe (SLGHP) performance is closely related to the subsurface heat transfer characteristics. Nevertheless, the relevant studies only considered heat conduction in rock formations and have used a two-dimensional axisymmetric model. In this work, a three-dimensional numerical model is established to simulate the heat extraction performance of SLHGP in the presence of groundwater seepage flow in geothermal resources. The key parameters, such as different seepage flow rates in the aquifer and different aquifer thicknesses and locations are investigated. Furthermore, a comparison is conducted with the coaxial downhole heat exchanger (CDHE) geothermal system under the same conditions. The results show that the larger seepage flow rate can provide a higher temperature boundary on the outer surface of the DHE, which can significantly improve the heat extraction of the system; the increase of aquifer thickness can effectively increase the heat convection area of DHE, thus improve the heat extraction performance; the closer the aquifer is to the bottom of earth, the better thermal performance of DHE due to the higher formation temperature; compared with the CDHE, under the same geothermal conditions, SLGHP has a better temperature homogenization performance, higher heat extraction, and does not consume pump power during operation. Therefore, it has significant advantages for efficiently extracting geothermal energy.

As the global demand for clean energy increases, photovoltaic power generation, as a renewable and environmentally friendly energy form, is gradually receiving attention. Floating photovoltaics, as one of the forms, has broad market prospects due to its advantages, such as higher power generation efficiency and reduced land occupation. By submersing part of the structure into the water, the semi-submersible floating structure can reduce the impact of environmental factors such as wind and waves and improve the operating efficiency and safety of floating photovoltaics. This paper uses Sesam software to perform numerical simulations to compare the effects of different significant wave heights, spectral peak periods, and wave incident angles on the hydrodynamic characteristics of the semi-submersible floating system. The results show that the structure has better stability under conditions of lower wave height, longer period, and along-wave motion. This article aims to provide the numerical basis for the design and performance optimization of semi-submersible floating structures through numerical simulation research and further promote the development of floating photovoltaic systems.

Underwater compressed air energy storage can solve the energy storage problem for large-scale offshore wind power. However, the performance of underwater gas pipelines is not fully understood at present. To understand the performance of the gas pipeline, the thermodynamic model of the energy storage and release process is built, and the effects of the diameter, length, and roughness of the gas pipeline are analyzed. The results show that: (1) the generating capacity of expander, energy recovery efficiency, and energy storage density for isobaric and isochoric compressed air energy storage are respectively 304.72 MW∙h, 65.73%, 6.09 kW∙h/m³ and 146.87 MW∙h, 59.45%, 2.94 kW∙h/m³ for gas pipeline diameter of 0.5 m, absolute roughness of 0.030 mm and energy storage depth of 500 m, showing that underwater compressed air energy storage has excellent performance; (2) the generating capacity of expander and energy recovery efficiency are respectively 580.28 MW∙h, 51.61%, 758.55 MW∙h, 68.34% and 794.63 MW∙h, 69.45% at energy storage depth of 1 000 m with gas pipeline diameter of 0.5 m, 0.7 m and ignoring gas pipeline resistance, indicating that the diameter of gas pipeline has an important effect on the energy storage system; (3) at energy storage depth of 500 m, the generating capacity of expander is reduced from 319.16 to 313.94 MW∙h and the energy recovery efficiency is also reduced from 69.23% to 67.94% when roughness varied from 0.005 to 0.250 mm, demonstrating that the roughness of gas pipeline has little effect on the energy storage system. The research results show that priority should be given to diameter rather than roughness when designing and selecting the underwater gas pipeline of underwater compressed air energy storage.

The development of natural gas hydrate inhibitors, especially combined inhibitors, has attracted significant attention to prevent the formation of natural gas hydrate in oil and gas extraction and transportation pipelines. This paper investigated the synergistic inhibition of glycine and polyvinylpyrrolidone (PVP) on the formation of methane hydrate and the influence of phase equilibrium. The methane hydrate formation experiment was carried out in a high-pressure reactor, and the inhibitory performance of kinetic inhibitors was evaluated by induction time. Experiment results show that glycine and PVP exhibit significant kinetic synergistic inhibition effects. When the concentration of PVP remains constant, an increase in the glycine concentration significantly prolongs the induction time of methane hydrate. The induction time of a system with a mass concentration of 5% PVP is 2.4 h, while that of 5% glycine + 5% PVP and 10% glycine + 5% PVP is 5.5 h and 10.5 h, respectively. The phase equilibrium conditions of methane hydrate formation in the presence of combined inhibitors of glycine and PVP were measured by differential scanning calorimetry at high pressure and low temperature. The methane hydrate phase equilibrium in the 13% glycine + 5% PVP system is 1.59 K lower compared with the pure water system. The hydrate structure was characterized by powder X-ray diffractometer and laser confocal micro Raman spectrometer. Glycine and PVP do not change the structural characteristics of methane hydrate.

Developing biodegradable materials from biomass is a key strategy in utilizing biomass resources. As the most important derivative of the furan ring system, furfural exhibits high chemical reactivity and adjustability. It can be used to prepare various types of degradable materials through multiple reactions. A new catalyst with a magnetic core-shell structure is developed, which is platinum-loaded onto a graphene-like shell and is applied to the catalytic hydrogenation of furfural in a water environment. Under different conditions, it is possible to selectively prepare furfuryl alcohol, tetrahydrofurfuryl alcohol, cyclopentanone, and cyclopentanol according to demand. This method provides an effective way for the high-value transformation of biomass waste, enabling the efficient synthesis of polymer materials and high-value-added pharmaceutical chemicals and demonstrating significant potential application value.