Wei Sun^1,2, Yanqing Feng^1,2,*, Yuan Wang^1,2, Zengping Zhao^1,2, Qian Wang², Xiangyun Li³, Dong Feng⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.22, No.1, 2026, DOI:10.32604/fdmp.2026.075630 - 06 February 2026

Abstract Significant differences exist between deep and medium-shallow coalbed methane (CBM) reservoirs. The unclear understanding of flowback and production behavior severely constrains the development of deep CBM resources. To address this challenge, guided by the gas-liquid two-phase flow theory in ultra-low permeability reservoirs, and integrating theoretical analysis, numerical simulation, and insights from production practices, this study classifies the flowback and production stages of deep CBM well considering the Daning-Jixian Block, Eastern Ordos Basin as a representative case. We summarize the flowback characteristics for each stage and establish a standard flowback production type curve, aiming to guide… More > Graphic Abstract

Zhirong Jin^1,*, Xiaorui Hou¹, Yanrong Ge¹, Tiankui Guo², Ming Chen², Shuyi Li², Tianyu Niu²

Energy Engineering, Vol.123, No.2, 2026, DOI:10.32604/ee.2025.070750 - 27 January 2026

Abstract Hydraulic fracturing serves as a critical technology for reservoir stimulation in deep coalbed methane (CBM) development, where the mechanical properties of gangue layers exert a significant control on fracture propagation behavior. To address the unclear mechanisms governing fracture penetration across coal-gangue interfaces, this study employs the Continuum-Discontinuum Element Method (CDEM) to simulate and analyze the vertical propagation of hydraulic fractures initiating within coal seams, based on geomechanical parameters derived from the deep Benxi Formation coal seams in the southeastern Ordos Basin. The investigation systematically examines the influence of geological and operational parameters on cross-interfacial fracture… More >

Dexiecia Anak Francis¹, Jalal Tavalaei¹, Hadi Nabipour Afrouzi^2,*

Energy Engineering, Vol.123, No.2, 2026, DOI:10.32604/ee.2025.070501 - 27 January 2026

Abstract Wave energy is a promising form of marine renewable energy that offers a sustainable pathway for electricity generation in coastal regions. Despite Malaysia’s extensive coastline, the exploration of wave energy in Sarawak remains limited due to economic, technical, and environmental challenges that hinder its implementation. Compared to other renewable energy sources, wave energy is underutilized largely because of cost uncertainties and the lack of local performance data. This research aims to identify the most suitable coastal zone in Sarawak that achieves an optimal balance between energy potential, cost-effectiveness, and environmental impact, particularly in relation to… More >

Li Wang¹, Xuesong Xing¹, Yanan Hou¹, Heng Wen¹, Ying Zhu¹, Jingyu Zi¹, Qingwei Zeng^2,3,*

Energy Engineering, Vol.123, No.2, 2026, DOI:10.32604/ee.2025.068653 - 27 January 2026

Abstract The deep coal reservoir in Linxing-Shenfu block of Ordos Basin is an important part of China’s coalbed methane resources. In the process of reservoir reconstruction, the artificial fracture morphology of coal seam with gangue interaction is significantly different, which affects the efficient development of coalbed methane resources in this area. In this paper, the surface outcrop of Linxing-Shenfu block is selected, and three kinds of interaction modes between gangue and coal seam are set up, including single-component coal rock sample, coal rock sample with different thicknesses of gangue layer and coal rock sample with different… More >

Yunpeng Wen^1,*, Bingyang Ke², Junrong Ding³

Chalcogenide Letters, Vol.23, No.1, 2026, DOI:10.32604/cl.2026.076587 - 26 January 2026

Abstract This study reports an active learning (AL)-guided strategy to optimize the sulfurization–selenization processing conditions of Sb₂(S,Se)₃ thin-film photovoltaic absorbers for enhanced power conversion efficiency (PCE). By coupling Gaussian process modeling with iterative experimental feedback, we explored 20 targeted annealing conditions across the full compositional spectrum (x = 0–1) and identified an optimal S/(S + Se) ratio of 0.40 (x = 0.60), which yielded a band gap (Eg) of ~1.34 eV, close to the theoretical Shockley–Queisser optimum. The optimized process employed a controlled two-step 420°C anneal with sequential H₂Se→H₂S exposure, which produced large plate-like grains (300–500 nm)… More >

Haoxuanye Ji^*, Zhiliang Chen, Pengfei Jiang, Ziyue Wang, Ting Yu, Wei Zhang

CMC-Computers, Materials & Continua, Vol.86, No.3, 2026, DOI:10.32604/cmc.2025.071880 - 12 January 2026

Abstract Foreign body classification on coal conveyor belts is a critical component of intelligent coal mining systems. Previous approaches have primarily utilized convolutional neural networks (CNNs) to effectively integrate spatial and semantic information. However, the performance of CNN-based methods remains limited in classification accuracy, primarily due to insufficient exploration of local image characteristics. Unlike CNNs, Vision Transformer (ViT) captures discriminative features by modeling relationships between local image patches. However, such methods typically require a large number of training samples to perform effectively. In the context of foreign body classification on coal conveyor belts, the limited availability… More >

Xia Yan¹, Wei Wang¹, Kai Shen^2,*, Yanqing Feng¹, Junyi Sun¹, Xiaogang Li¹, Wentao Zhu¹, Binbin Shi¹, Guanglong Sheng^2,3

Energy Engineering, Vol.123, No.1, 2026, DOI:10.32604/ee.2025.070360 - 27 December 2025

Abstract In the development of coalbed methane (CBM) reservoirs using multistage fractured horizontal wells, there often exist areas that are either repeatedly stimulated or completely unstimulated between fracturing stages, leading to suboptimal reservoir performance. Currently, there is no well-established method for accurately evaluating the effectiveness of such stimulation. This study introduces, for the first time, the concept of the Fracture Network Bridging Coefficient (FNBC) as a novel metric to assess stimulation performance. By quantitatively coupling the proportions of unstimulated and overstimulated volumes, the FNBC effectively characterizes the connectivity and efficiency of the fracture network. A background… More >

Marija Macenić, Tomislav Kurevija^*, Tin Herbst

Energy Engineering, Vol.123, No.1, 2026, DOI:10.32604/ee.2025.067067 - 27 December 2025

Abstract The increased interest in geothermal energy is evident, along with the exploitation of traditional hydrothermal systems, in the growing research and projects developing around the reuse of already-drilled oil, gas, and exploration wells. The Republic of Croatia has around 4000 wells, however, due to a long period since most of these wells were drilled and completed, there is uncertainty about how many are available for retrofitting as deep-borehole heat exchangers. Nevertheless, as hydrocarbon production decreases, it is expected that the number of wells available for the revitalization and exploitation of geothermal energy will increase. The… More >

Ghinwa Al Mimar¹, Natrah Kamaruzaman^1,*, Kamil Talib Alkhateeb²

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1933-1956, 2025, DOI:10.32604/fhmt.2025.070118 - 31 December 2025

Abstract The pivotal role microchannels play in the thermal management of electronic components has, in recent decades, prompted extensive research into methods for enhancing their heat transfer performance. Among these methods, surface wettability modification was found to be highly effective owing to its significant influence on boiling dynamics and heat transfer mechanisms. In this study, we modified surface wettability using a nanocomposite coating composed of graphene nano plate (GNPs) and multi-walled carbon nanotubes (MWCNT) and then examined how the modification affected the transfer of boiling heat in microchannels. The resultant heat transfer coefficients for hydrophilic and… More >

Luthfi Hakim^1,*, Yunida Syafriani Lubis², Apri Heri Iswanto¹, Harisyah Manurung¹, Jayusman², Widya Fatriasari³, Petar Antov⁴, Tomasz Rogoziński⁵, Lee Seng Hua⁶, Nur Izyan Wan Azelee⁷

Journal of Renewable Materials, Vol.13, No.12, pp. 2355-2373, 2025, DOI:10.32604/jrm.2025.02025-0078 - 23 December 2025

Abstract Activated charcoals were synthesized from sugar palm bunches (SPB) of the native tree of Arenga longipes in Indonesia. The synthesized activated charcoal (AC) was characterized, and utilized as an absorbent for heavy metals (lead/Pb and copper/Cu) through thermal activation. The synthesis of AC was accomplished through furnace activation at temperatures of 500°C, 600°C, 700°C, and 800°C. Acid chlorides were blended with the SPB-AC samples at 5% impregnation level and subsequently subjected to washing for activation, resulting in the elimination of volatile substances and ash content, which facilitates the development of a porous structure in the activated… More >