Supercapacitors have received widespread attention for their high-power density, excellent multiplier performance, and good cycling stability among many energy storage elements. The main research direction nowadays is the use of low-cost, green and clean biomass with high carbon content as the raw material for electrodes. This paper reviews the adaptability of biochar preparation methods including pyrolysis, hydrothermal, and gasification to be used as raw materials for electrodes; analyzes the effects of properties such as specific surface area, pore structure, functional groups, conductivity, and vibrational density of biochar on the performance of supercapacitors; discusses the effects of modification methods such as physical activation, chemical activation, heteroatom doping, composite of conductive polymers and biochar, and composite of metal oxides and biochar on the supercapacitor performance enhancement; and compared the performance of common biomass types such as woody, marine, herbaceous, and fruit biomass in supercapacitor applications. Based on the above analysis, it is recommended that the development direction of biomass as supercapacitor electrode materials is to use pyrolysis as the common way of making charcoal, with a high specific surface area and suitable mesoporous-microporous ratio as the main objectives of structural modification, and to increase the specific capacitance by doping with heteroatoms or conductive polymers, etc. Among the many biomasses, the woody biomass has become the main target of the study due to its well-developed pore space, low ash content, high cellulose content, and other advantages. It can prepare biochar with a multistage porous structure and ultra-high carbon content and produce high-performance supercapacitor electrode materials.

A phosphorus/tin composite carbon fiber skeleton is designed to tackle the challenge of lithium dendrite growth. Sn serves as the nucleation site to reduce the nucleation barrier of Li⁺, while the P doped on the carbon fibers could promote the rapid transportation of Li⁺. Thus, the CFs@Sn-P enables the uniform deposition of lithium in the skeleton and inhibits the Li dendrite growth. The electrochemical performances demonstrated that the CFs@Sn-P could effectively elevate the Coulombic efficiency and mass transfer kinetics of Li⁺, and exhibit excellent cycle stability and rate performance. At the rate of 1 C and N/P ratio of 2.5, Li-CFs@Sn-P||NCM811 cells can stably cycle 250 times, and the average capacity decay rate is only 0.14%. Hence, a composite skeleton's design could guide the design and application of high-performance lithium metal anode.

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.

With the yearly increase in installed wind power, the disposal of retired wind turbine blades has become an urgent issue. In this study, a continuous microwave pyrolysis-oxidation system with a processing capacity of 30 kg/h was developed. The recovery efficiency of carbon fibers from carbon fiber reinforced plastics (CFRP) with a carbon fiber content of 65% was investigated under different microwave powers and oxidation temperatures. Thermal gravimetric (TG) analysis and scanning electron microscopy (SEM) were employed to compare the thermal decomposition behavior and surface morphology of fresh carbon fibers, pyrolysis products, and oxidation products, respectively. The results show that pyrolysis of CFRP with 18 kW microwave power for 90 mins followed by oxidation at 550 °C for 150 mins results in a carbon fiber recovery efficiency of 63.83%. TG results indicate that in the N₂ atmosphere the epoxy resin component of the CFRP undergoes thermal decomposition between 300 ℃ and 450 °C, with peaks at 366.8, 435.0, 561.6 and 870.3 ℃ in oxidation atmosphere. Fresh carbon fibers' initial decomposition and oxidation temperatures are 650 ℃ and 600 ℃, respectively. SEM results demonstrate that the surface morphology of carbon fibers recovered from pyrolysis with 18 kW microwave power followed by oxidation at 550 ℃ was basically the same as that of fresh carbon fibers. It shows that the device can remove the resin in the carbon fiber composite plate and recover high-quality carbon fiber under the operating conditions. This research provides valuable insights into the recycling utilization of retired carbon fiber wind turbine blades.

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.

To improve the efficiency of thermal energy storage and utilization, this study investigates the enhancement characteristics of efficient contact melting on the thermal performance of finned latent heat storage units. A fully coupled contact melting heat transfer model that considers solid conduction, natural convection, and solid phase change material motion is established based on a modified equivalent heat capacity method. It explores the evolution of the melting front morphology, convective heat transfer characteristics, and dynamic temperature performance of traditional constrained melting and contact melting processes in finned latent heat storage units. Additionally, an in-depth analysis is conducted on the influencing mechanisms of the heat transfer fluid's inlet temperature and volume flow rate on high-efficiency contact melting. The research findings indicate that both constrained melting and contact melting are initially dominated by heat conduction, while in the later stages of melting, natural convection and mixed convection heat transfer modes are induced in constrained melting and contact melting processes, respectively. Compared to constrained melting, the melting rate and heat transfer uniformity of contact melting are improved, with the complete melting time in the finned latent heat storage unit reduced by 36.7%. An increase in the inlet temperature enhances the performance of contact melting, but the degree of enhancement gradually diminishes. As the volume flow rate increases, the heat transfer performance of contact melting improves, but the extent of change is smaller than the effect of the inlet temperature. Furthermore, there is a critical volume flow rate beyond which the thermal performance of contact melting remains nearly unchanged.

A novel silicon oxycarbonitride (SiOCN) composite is synthesized through an aldimine condensation of 3-aminopropyltriethoxysilane with formaldhyde and simultaneous hydrolysis of alkoxy, followed by subsequent thermal pyrolysis. The electrochemical performance of SiOCN as anode material is comparatively studied with the addition of a commercial electrolyte additive of fluoroethylene carbonate (FEC) and a lab-made organic fluorosilane electrolyte additive (MFSM2) in the base electrolytes. In comparison to the base electrolyte, the initial reversible capacity increases from 614.6 mA∙h/g to 899.9 mA∙h/g and 886.9 mA∙h/g for the electrolyte with MFSM2 and FEC additive, respectively. Correspondingly, the initial coulombic efficiency increases from 58.3% to 62.2% and 62.8%. The results of cyclic voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy showed that the addition of additives reacted on the surface of the SiOCN electrode to form a stable, uniform, and dense solid electrolyte interphase, which reduced the interfacial impedance and increased the ion transport rate, thus improving the electrochemical performance of the SiOCN cell.

Ultra-high temperature steam heat pump is a highly promising industrial high-temperature heating and decarbonization technology. The working fluids used in steam heat pumps are becoming increasingly environmentally friendly. Natural working fluids such as water and hydrofluoroalkenes have become the research focus. R1336mzz-Z, R1234ze-Z, and R1233zd-E have the most promising commercial promotion prospects. Cascade compression, two-stage compression, and steam recompression are the main cycle forms that ensure the high-temperature output of steam heat pumps. Centrifugal compressors and screw compressors are the most widely used and promising types of compressors in steam heat pumps. The technology of adding vapor or water in the middle of the compressor has become an effective measure to reduce the compressor's discharge temperature and enhance its high-temperature stability. The test results of steam heat pump units show that the heating coefficient of performance (COP) of steam heat pump units decreases with the increase of temperature lift and output temperature. Currently, for most steam heat pumps, the steam production temperature is below 200 °C, the temperature rises below 60 °C, and the heating COP is between 2.5 and 3.2. With the increasing demand for carbon reduction technology in industrial enterprises, steam heat pumps have entered a period of rapid development opportunities in China. 120 °C steam heat pumps have become the mainstream of the industry. The future development goal of steam heat pump manufacturers is to produce higher-temperature steam.

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.

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 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 acoustic characteristics of hydrate-bearing sediments are influenced by factors such as hydrate saturation and micro-distribution modes, skeleton particle arrangement and shape, etc. Currently, there is a lack of research on the influence mechanisms of skeleton particle arrangement and particle shape. Finite-element numerical models of hydrate-bearing sediments were established based on the coupling modeling method of electrical-mechanical-acoustic multi-physics fields under conditions of different particle arrangement modes and particle shapes. The influences of skeleton particle arrangement modes and shapes on sediments' sound velocity and attenuation characteristics under different hydrate micro-distribution modes and saturation conditions were explored, and the mechanisms were discussed. It was demonstrated that: (1) when the hydrate saturation is low, the volumetric proportion of quartz sand particles in the diamond-arrangement model is higher than that in the cubic-arrangement model, thus the sound velocity of the diamond-arrangement model is higher; as the hydrate saturation increases, the difference in the volumetric proportion of hydrates between the two models increases and the volumetric proportion of hydrates in the cubic-arrangement model is higher, consequently the sound velocity growth rate in the diamond-arrangement model is lower; (2) the porosity of the diamond-arrangement model is smaller than that of the cubic-arrangement model, and the energy attenuation during the propagation of sound waves is lower; (3) compared with the spherical-particle model, the elliptical-particle model contains more pores with smaller aspect ratios, resulting in a smaller bulk modulus and lower sound velocity; (4) the ellipsoidal-particle model contains more and smaller pores, which results in lower wave-energy loss than that of the spherical particle model. This study provides theoretical support for the data interpretation of seismic exploration and sonic logging for natural gas hydrate reservoirs.

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.

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.

Lithium-ion batteries have the risk of thermal runaway under abusive conditions, which can easily lead to fire and even explosion accidents. Preventing thermal runaway in lithium-ion batteries is important for their safe application. This study selected the 147 A∙h square ternary lithium-ion batteries as the experimental object, and utilized various types of thermal insulation materials, such as phase change thermal insulation materials, glass fiber aerogel, and basalt fiber aerogel to inhibit the thermal runaway propagation of battery packs. This paper explored the influence of different types and thicknesses of heat mitigation materials on the behavior of thermal runaway propagation. Additionally, a commercial thermal runaway warning sensor was used for monitoring and early warning. The results indicated that the 2.5 mm phase change thermal insulation materials and glass fiber aerogel plate could not block the thermal runaway propagation. However, the thermal runaway propagation process can be suppressed using the basalt fiber aerogel plates with 2.0, 2.5, and 3.0 mm thicknesses. The maximum temperature of the downstream battery rear surface is 134.0, 185.9, and 102.5 ℃, respectively. When using a 3.0 mm basalt fiber aerogel plate, the heat runaway early warning sensor successfully realizes early warning, and the downstream battery still has the ability to discharge normally. This study provides a design basis and theoretical guidance for the safe design of lithium-ion battery packs and the development of thermal runaway propagation barrier technology.

With the escalating global carbon dioxide emissions, the incessant rise in greenhouse gas concentrations has profoundly impacted human beings and the earth's ecosystems. Hydrogen energy, renowned for its abundant reserves, high energy efficiency, and zero carbon emissions, is a pivotal means to achieve carbon peaking and neutrality goals, instigating a profound energy revolution. This research paper aims to provide an overview of the key aspects of the hydrogen energy industry, encompassing hydrogen production, storage and transportation, refueling, and utilization, specifically emphasizing the application of artificial intelligence (AI). Furthermore, this paper delves into the future trends and prospects of fusion development between hydrogen energy and AI technologies.

Wave energy is a green and clean energy source, abundant wave energy resources are found around the island. In recent years, with wave energy utilization technology development, many new types of technology have appeared, and some technologies are becoming mature. Applying of wave energy technology has gradually become a hot spot in the industry. Taking wave energy generation technology as the starting point, the new wave energy generation technology emerging recently is summarized, and the application of wave energy generation technology on islands in China is summarized. Based on the above analysis, the future development direction of wave energy technology in China is prospected from system theory, technology maturity, and technology application.

Micro light-emitting diode (Micro LED) display is a novel display technology composed of micro-level semiconductor light-emitting pixel arrays, a comprehensive technology that integrates display and LED technology. Compared with liquid crystal displays and organic light-emitting diode displays, Micro LED has the advantages of high contrast, low power consumption, long life, and fast response time. However, due to the low absorption cross-section caused by the shrinking LED chip size to less than 20 μm, traditional phosphor color conversion cannot provide sufficient brightness and does not support high-resolution displays. Quantum dot materials are expected to be the best materials to replace phosphors due to their high quantum yield, wide color gamut, and adjustable colors. Micro LED optoelectronic devices combined with quantum dot color conversion technology have the advantages of high brightness, high efficiency, and wide color gamut, and they have broad application prospects in the display field. Researchers in academia and industry have conducted in-depth research on Micro LED with full-color display and gradually realized the commercialization of Micro LED. This paper briefly reviews significant research findings on the synthesis and excellent properties of quantum dot materials widely used in the display field. Furthermore, it summarizes the full-color display strategies as well as the performance advantages and disadvantages of Micro LED based on quantum dot color conversion technology by classifying four outstanding color conversion layer deposition processes—printing technology, lithography technology, microfluidic technology, and laser writing technology. Finally, the application prospects of Micro LED optoelectronic devices based on quantum dot color conversion layers are discussed.

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.

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.

Wind energy plays a crucial role in the renewable energy system. However, as the number of discarded wind turbine blades increases annually, recycle ing and utilizing these blades has become an urgent necessity. The pyrolysis-oxidation treatment of wind turbine blades has the advantages of reducing volume and recycling reinforced fiber from the blades. While research on recovering carbon fiber when used as reinforced fiber is available, few research pays attention to recycling glass fiber. To improve the mechanic strength of the recovered glass fiber and reduce energy consumption in this process, in this paper, key parameters in the pyrolysis-oxidation process, including the decarburization temperature, holding time, and heating rate, are optimized based on the response surface method with the fracture load of the recycled glass fiber as the response value to achieve the best mechanical properties of the recycled fiber, and the interaction between the three key parameters was also explored. The results show that the decarburization temperature plays most significant role in the fracture load, and the holding time and heating rate also play the important roles in the fracture load. The optimized process parameters are a decarburization temperature of 452.45 °C, a reaction time of 43.20 min, and a heating rate of 11.12 °C/min. The experimental results proved that those values are most suitable; the fracture load of the recycled fiber obtained after optimization achieved 51.2% of the new material, and the optimized process is more energy effective.

Improving wind speed prediction accuracy is important for timely adjustments in power system scheduling plans and enhancing competitiveness in the wind energy market. This paper presents an ultra-short-term wind speed forecasting method based on an ensemble of convolutional neural network (CNN), long short-term memory network (LSTM), and autoregressive integrated moving average (ARIMA). Firstly, CNN convolutional layers capture patterns and local features in time series data. Subsequently, it utilizes LSTM models to learn and train on the extracted features. Based on the CNN-LSTM composite architecture model, it predicts future wind speeds and compares them with actual data to obtain residuals. Finally, it employs ARIMA to analyze historical residuals to correct future prediction errors, achieving ultra-short-term wind speed forecasting. Using measured wind speed data from a wind farm in Turkey as an example, it predicts wind speeds for the next 10 minutes. The results indicate that compared to traditional neural network models like CNN-LSTM and LSTM-LSTM, the CNN-LSTM-ARIMA model has reduced the mean absolute error in wind speed forecasting by 16.40% and 26.92%, respectively, significantly enhancing the prediction accuracy.

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.

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.

The Gobi desert wind farm cluster is characterized by large diurnal temperature differences, susceptibility to atmospheric stability, and a lack of representative wind measurement data. It is urgent to assess the wind resource characteristics of the Gobi desert wind farm. This study focused on the wind farm in Inner Mongolia's Alxa League, which was under construction then. Weather research and forecasting models were utilized for numerical simulation. Wind measurement data was employed to validate the model's accuracy, emphasizing the spatial and temporal distribution characteristics of atmospheric stability and its impact on wind speed. The research indicates that wind speed and wind power density in the region are higher from November to May of the following year, particularly affected by the northwest monsoon, with a sharp decrease in wind power accompanying the passage of cold waves. The proportion of neutral atmospheric conditions peaks in winter, and wind speeds are optimal under neutral conditions. Compared to flat terrain, mountainous regions exhibit a significant decrease in the proportion of strongly stable and strongly unstable atmospheric states, with a corresponding increase in the proportion of neutral atmospheric stability. Specifically, the proportion of neutral atmospheric conditions in mountainous regions during winter can reach 48.4%, providing theoretical and technical support for the micro-site selection of the Gobi desert wind farm cluster.

The technology of obtaining gasoline from non-petroleum resources by Fischer-Tropsch synthesis is an effective way to develop the efficient and profitable use of carbon-containing resources, the key of which is the catalyst. In view of the problems of low utilization efficiency of biomass syngas and the need to improve hydrocarbon selectivity of C₅ - C₁₁ by Fischer-Tropsch catalysts, a bifocal catalyst system with Fe₂O₃ as Fischer-Tropsch synthesis site and fractionated porous zeolite as pyrolysis site was constructed in this study, with a view to coupling C₅₊ hydrocarbon synthesis and C₁₂₊ hydrocarbon cracking in one step. The highly selective synthesis of C₅ - C₁₁ hydrocarbons was achieved. It was found that the catalyst introduced by molecular sieve showed better catalytic performance than that of zeolite-free catalyst. The Fe₂O₃ + HZSM5 catalyst showed the best catalytic performance, the ferric time yield of the Fischer-Tropsch reaction for 24 h was 42.3 μmol∙g⁻¹∙s⁻¹, and the C₅₊ product yield was 3.74 × 10⁻³ g∙g⁻¹∙s⁻¹. The selectivity of C₅₊ was 63.6%, the selectivity of iso-alkane was 42.0%, and the conversion of CO was 73.1%.

The permeation behavior of hydrogen and helium in the liner of a type IV high-pressure hydrogen storage vessel, specifically nylon 6 (PA6), was studied. The effects of temperature on the permeation behavior and the differences between the two gases were analyzed. Within the test temperature range of 15-55 °C, the permeation coefficient of hydrogen was higher than that of helium, and both increased with temperature. However, comparing the activation energy for permeation, it was found that helium had a stronger dependence on temperature increase. By comparing the permeation coefficients of the two gases under the same test conditions, the range of conversion coefficients for the two gases was obtained, providing data support for the replacement of hydrogen by helium.

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.

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.

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.

Ice slurry is a typical solid-liquid two-phase fluid that generates significant friction on the pipe wall during flow. It is also a clean and pollution-free medium, making it ideal for pipeline cleaning. The particle size, flow rate, and ice packing factor of ice slurry greatly impact the flow characteristics of ice slurry, which in turn affects the pipeline cleaning ability. This paper first investigates the changes in particle size of ice slurry during the aging process through experimental methods, and then studies the influencing factors of the flow characteristics of ice slurry in pipelines using the Euler-Euler model simulation method. The results indicate that after the ice slurry flow with 40% ice packing factor is fully developed, the ice packing factor at the bottom can reach 25%, resulting in better cleaning at the bottom. In addition, flow velocity is the most significant factor affecting ice slurry flow shear stress. Adjusting the initial conditions of ice slurry based on influencing factors can guide actual pipeline cleaning work.

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.

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.

The natural convection of locally heated air outside a vertical cylinder was investigated to explore the gas flow of the steady smoldering of a vertical rod fuel. The influences of cylinder diameter, length of high-temperature zone, and heating temperature on natural air convection were analyzed based on the verification of the calculation method. The results show that the air mass flow rate increases in a quadratic relationship with the increasing diameter of the cylinder and in a linear relationship with the length of the high-temperature zone. When the cylinder diameter increased from 3 mm to 11 mm, the air mass flow rate increased by 3.54 times. When the length of the high-temperature zone increased from 5 mm to 13 mm, the air mass flow rate increased by 1.97 times. The calculated variation is larger than the influence of the reaction zone size on the smoldering rate.

The hydrate method for carbon capture and storage (CCS) of flue gas is a clean and efficient approach. This paper analyzed and calculated the CO₂ capture efficiency and energy consumption of the hydrate-based separation process using liquid/gas molar ratio, driving force, subcooling, CO₂ concentration of the gas mixture, and phase equilibrium condition as key parameters. The results indicated an optimal liquid/gas molar ratio in the hydrate separation process of flue gas with different CO₂ concentrations, which corresponded to minimum unit energy consumption. The hydrate-based separation process of flue gas containing 20% CO₂ had an optimal liquid/gas molar ratio of 5.5, which can obtain a minimum unit energy consumption of 1.10 kW∙h/kg. The CO₂ recovery rate and CO₂ concentration of CO₂-rich gas were 97% and 73%, respectively. The higher the driving force, the lower the CO₂ concentration and recovery rate. While increased subcooling can increase CO₂ capture, the higher driving force or subcooling was unbeneficial to separation results. Although increasing the CO₂ concentration of the gas mixture can save the compressor's energy consumption, the refrigeration energy consumption has significantly increased. The CO₂ concentration increased from 10% to 40%, and the refrigeration energy consumption increased from 19% to 47%. By analyzing the influence of phase equilibrium conditions corresponding to 274 K and 278 K on separation energy consumption, it was found that the separation efficiency and unit energy consumption under 274 K conditions were better than those under 278 K. Therefore, low-temperature separation condition was advantageous for separation results.

Astaxanthin is an essential class of lutein carotenoids widely used in food, cosmetics, and pharmaceuticals due to its exceptional antioxidant qualities and distinct molecular structure. Natural astaxanthin and synthetic astaxanthin are the two types of astaxanthin, where the antioxidant properties of natural astaxanthin are higher than those of synthetic astaxanthin, and there is an increasing consumer preference and demand for natural astaxanthin. Thus, extracting of natural astaxanthin from bioresources has great market value and application potential. Because of their high solubility, low volatility, recyclability, and structural designability, ionic liquids have achieved remarkable research results in natural astaxanthin extraction compared to organic solvents as extractants. This paper first introduces the structural cosmetics, applications, and sources of natural astaxanthin, then reviews the commonly used extraction methods of astaxanthin, and elaborates on the research advances of natural astaxanthin extraction by ionic liquid systems in recent years to provide a reference value for the in-depth research and development application of natural astaxanthin extraction.

Finding environmentally friendly and efficient hydrate inhibitors is crucial for preventing hydrate formation in oil and gas pipelines, ensuring flow safety, and promoting the development of green oilfields. Natural products such as amino acids and their short peptides are gaining attention due to their biodegradable and environmentally friendly properties. This study employed molecular dynamics simulations to investigate the inhibitory effects of glycine and its short peptides on methane hydrate growth at 250 K and 50 MPa. It compared them with the inhibitory effects of poly(N-vinylcaprolactam) (PVCap) on methane hydrate growth. The simulation results showed that the inhibitory effect of glycine pentapeptide was comparable to PVCap, followed by glycine tripeptide, while the inhibitory effect of glycine monomer was relatively weak. Furthermore, analysis of parameters such as mean square displacement, radial distribution function, and hydrogen bonding revealed the mechanism of action of amino acid inhibitors: the H atoms of the carboxyl group in glycine and its short peptides interacted with water molecules to disturb the structure of the hydrate cages, while the double-bond O atoms of the carboxyl group interacted with the H atoms of water molecules to disrupt the structure of water molecules. Compared to amino acid monomers, the carbon chains of short peptides prevented methane and water molecules from moving to the surface of the hydrates, thereby exhibiting stronger inhibitory effects on hydrate growth. The research findings provide a theoretical basis and data support for guiding the design and screening of green hydrate dynamic inhibitors.

The active power compensation device has addressed the issue of output power pulsation in the hydraulic autonomous control mode of wave energy converters during the startup or shutdown of the generator set. However, a problem arises with the overcharging or over-discharging of its energy storage system. In order to reduce battery capacity while maintaining the battery's high-power charging and discharging capabilities at any time, a method for configuring a small-capacity energy storage system and a management strategy for dividing interval energy trends are proposed. Based on the characteristics of the hydraulic power generation system and the working principle of the active power compensation device, the energy storage system is configured with the minimum capacity as the target, taking the smoothing of the maximum pulsating power of the unit as a benchmark. The charging status and voltage of the energy storage system are divided into intervals, and the trend power is determined to automatically adjust the state of charge of the energy storage system towards the trend. This ensures that the system can always absorb and compensate, avoiding overcharging or over-discharging. A simulation model for smoothing the grid power fluctuation of the hydraulic power generation unit was established, and simulation results indicate that the energy trend management strategy can maintain the energy storage system in a reasonable operating range for an extended period, validating the rationality of the interval energy trend management strategy.

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 optimization of wind turbine structure is of paramount importance for enhancing energy conversion efficiency. To explore the influence of four structural parameters—number of blades (n), radius (R), aspect ratio (μ), and installation angle (β)—on the aerodynamic performance of vertical-axis wind turbines at a low cost, an orthogonal experimental design based on the Taguchi method and a modified additive model were employed. This approach determined the optimal design parameters for maximizing the wind turbine's power output and conducted CFD numerical validation studies. The results indicate that the combination of the Taguchi method and the modified additive model can accurately determine the optimal parameter combination and assess the extent of influence each factor has on aerodynamic performance. The analysis indicates that the wind turbine exhibits the strongest performance at n = 3, R = 2.5 m, μ = 8, β = -3°, and the weakest performance at n = 5, R = 1.0 m, μ = 5, β = 0°. The average power coefficient of the optimal configuration is 66.12% greater than that of the worst configuration. Furthermore, the magnitude of the influence of each factor on the efficiency of the vertical axis wind turbine is R > n > β > μ.