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19 pages, 3833 KB  
Article
Cucurbitacin B Inhibits Hepatocellular Carcinoma by Inducing Ferroptosis and Activating the cGAS-STING Pathway
by Huizhong Zhang, Aqian Chang, Xiaohan Xu, Hulinyue Peng, Ke Zhang, Jingwen Yang, Wenjing Li, Xinzhu Wang, Wenqi Wang, Xingbin Yin, Changhai Qu, Xiaoxv Dong and Jian Ni
Curr. Issues Mol. Biol. 2026, 48(2), 138; https://doi.org/10.3390/cimb48020138 - 27 Jan 2026
Abstract
The incidence of primary liver cancer is increasing annually, with extremely high mortality and suboptimal therapeutic outcomes. The inefficient presentation of tumor antigens and low infiltration of specific cytotoxic T lymphocytes (CTLs) result in insufficient immunogenicity, which limits the efficacy of immunotherapy. Despite [...] Read more.
The incidence of primary liver cancer is increasing annually, with extremely high mortality and suboptimal therapeutic outcomes. The inefficient presentation of tumor antigens and low infiltration of specific cytotoxic T lymphocytes (CTLs) result in insufficient immunogenicity, which limits the efficacy of immunotherapy. Despite the popularity of immune checkpoint inhibitors (ICIs), insufficient immune activation means only a small subset of hepatocellular carcinoma (HCC) patients exhibit clinical responses to ICIs, showing significant inter-individual variability. The activation of the cyclic GMP-AMP synthase(cGAS)- stimulator of interferon genes(STING) pathway initiates the expression of type I interferons (IFNs) and inflammatory cytokines, promoting the formation of a pro-inflammatory environment at the tumor site. This pathway enhances anti-tumor immune responses by facilitating antigen processing and presentation, T cell priming and activation, and remodeling of the immunosuppressive microenvironment. Our research found that cucurbitacin B (CuB), a natural component derived from traditional Chinese medicine, had significant anti-hepatocellular carcinoma properties and exerted anti-tumor effects through the cGAS-STING pathway. Specifically, CuB regulated ferroptosis by down-regulating the expression of Solute Carrier Family 7 Member 11 (SLC7A11) and Glutathione Peroxidase 4 (GPX4) and upregulating the expression of Transferrin Receptor Protein 1 (TFR1) and Long-chain Acyl-CoA Synthetase 4 (ACSL4). These actions involved lipid substrates, iron ion homeostasis, and antioxidant defense systems. The release of mitochondrial DNA (mtDNA) triggered by ferroptosis activated the cGAS-STING immune signaling pathway, leading to the up-regulation of cGAS, phosphorylated STING (p-STING), phosphorylated TANK-binding kinase 1 (TBK1), phosphorylated Interferon regulatory factor3 (IRF3), and Interferon-β (IFN-β). This cascade activation pattern provides new insights into the drug treatment of tumors. Full article
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11 pages, 322 KB  
Article
Gothelf’s Haplotype of COMT in Parkinson’s Disease: A Case–Control Study
by Zdenko Červenák, Ján Somorčík, Žaneta Zajacová, Andrea Gažová, Igor Straka, Zuzana André, Michal Minár and Ján Kyselovič
Biomedicines 2026, 14(2), 262; https://doi.org/10.3390/biomedicines14020262 - 23 Jan 2026
Viewed by 98
Abstract
Background: Catechol-O-methyltransferase (COMT) catalyzes catecholamine O-methylation and contributes to dopamine turnover, potentially influencing levodopa requirements in Parkinson’s disease (PD). We evaluated whether the Gothelf COMT haplotype—and its constituent variants rs2075507, rs4680 (Val158Met), and rs165599—differ in frequency between PD cases and controls. We then [...] Read more.
Background: Catechol-O-methyltransferase (COMT) catalyzes catecholamine O-methylation and contributes to dopamine turnover, potentially influencing levodopa requirements in Parkinson’s disease (PD). We evaluated whether the Gothelf COMT haplotype—and its constituent variants rs2075507, rs4680 (Val158Met), and rs165599—differ in frequency between PD cases and controls. We then tested associations between these variants and clinical phenotypes, with a prespecified focus on levodopa equivalent daily dose (LEDD). Finally, we examined whether haplotype structure and allele-specific context (e.g., background-dependent effects) help explain observed genotype–phenotype relationships in the PD cohort. Aim: Analysis of the rs2075507, rs4680 and rs165599 at individual and haplotype level between control and diseased groups. Furthermore, analysis of association of individual SNPs or haplotype level with clinical outcomes. Subjects and methods: Fifty-five individuals with Parkinson’s disease (PD) and fifty-three neurologically healthy controls were enrolled at a single center. Genomic DNA was isolated from peripheral blood, and three COMT variants—rs2075507 (promoter), rs4680/Val158Met (coding), and rs165599 (3′UTR)—were genotyped by Sanger sequencing. Allele, genotype, and tri-marker haplotype frequencies were estimated, and case–control differences were evaluated. Within the PD cohort, associations with clinical outcomes—primarily levodopa equivalent daily dose (LEDD)—were analyzed using multivariable linear models. Statistical tests were two-sided, with multiplicity control as specified in the corresponding tables. Results: The rs2075507 polymorphism showed a robust additive association with LEDD; each A allele predicted higher dose (LEDD ≈ +1331 mg/day, p = 0.001) after adjusting for age and sex. The tri-haplotype test did not show significant association with LEDD. Nevertheless, rs2075507 SNP strongly marked downstream backgrounds: in AA carriers, rs4680–rs165599 haplotypes were enriched for Val (G) and rs165599-G; in GG carriers, for rs165599-A with mixed Val/Met; and GA was A-loaded at both loci. Exact tests confirmed that AA and GG differed in rs4680–rs165599 composition, whereas GA vs. GG was not significant. Conclusions: The promoter variation at rs2075507 may represent the genetic contributor to levodopa dose requirements when modeled with SNP–SNP interactions, with its effect is modified mostly by rs165599 polymorphism. Tri-haplotypes do not independently predict LEDD. The rs4680 (coding) and rs165599 (3′UTR) context appears to fine-tune rather than determine dosing needs, mainly via interaction with rs2075507 SNP. Full article
(This article belongs to the Special Issue Advances in Parkinson’s Disease Research)
20 pages, 2303 KB  
Article
Numerical Investigation of Sustainable Diesel Engine Performance and Emissions Using Directly Integrated Steam Methane Reforming Syngas
by Tolga Bayramoğlu, Kubilay Bayramoğlu, Semih Yılmaz and Kerim Deniz Kaya
Sustainability 2026, 18(2), 1012; https://doi.org/10.3390/su18021012 - 19 Jan 2026
Viewed by 139
Abstract
The transition toward sustainable energy systems necessitates innovative solutions that reduce greenhouse gas emissions while improving fuel efficiency in existing combustion technologies. Hydrogen has emerged as a promising clean energy carrier; however, its widespread deployment is limited by challenges associated with large-scale transportation [...] Read more.
The transition toward sustainable energy systems necessitates innovative solutions that reduce greenhouse gas emissions while improving fuel efficiency in existing combustion technologies. Hydrogen has emerged as a promising clean energy carrier; however, its widespread deployment is limited by challenges associated with large-scale transportation and storage. This study investigates a practical alternative in which hydrogen-rich syngas produced via steam methane reforming (SMR) is directly integrated into the diesel engine intake, thereby eliminating the need for fuel transport, storage, and separation while supporting a more sustainable fuel pathway. A validated computational fluid dynamics (CFD) model was developed to examine the effects of varying SMR gas mixture ratios (0–20%) on engine combustion, performance, and emissions. The findings reveal that increasing the SMR fraction enhances in-cylinder pressure by up to 15.7%, heat release rate by 100%, and engine power output by 102.5% compared to conventional diesel operation. Additionally, under SMR20 conditions, CO2 emissions are reduced by approximately 12%, demonstrating the potential contribution of this approach to decarbonization and climate mitigation efforts. However, the rise in in-cylinder temperatures was found to increase NOx formation, indicating the necessity for complementary emission control strategies. Overall, the results suggest that direct SMR syngas integration offers a promising pathway to improve the environmental and performance characteristics of conventional diesel engines while supporting cleaner energy transitions. Full article
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14 pages, 1110 KB  
Article
Rheological and Stability Assessment of Alternative Polymer Modifiers for Coal Dust Combustion
by Krystian Czernek, Andżelika Krupińska, Kamil Makowski, Marek Ochowiak, Magdalena Matuszak, Zdzisław Bielecki, Ivan Pavlenko and Sylwia Włodarczak
Appl. Sci. 2026, 16(2), 956; https://doi.org/10.3390/app16020956 - 16 Jan 2026
Viewed by 121
Abstract
This study focuses on the development and physicochemical evaluation of an alternative liquid carrier for coal dust combustion modifiers containing solid catalyst particles. A commercially used acrylic-polymer-based carrier, whose viscosity is regulated by sodium hydroxide addition, was investigated and compared with a proposed [...] Read more.
This study focuses on the development and physicochemical evaluation of an alternative liquid carrier for coal dust combustion modifiers containing solid catalyst particles. A commercially used acrylic-polymer-based carrier, whose viscosity is regulated by sodium hydroxide addition, was investigated and compared with a proposed safer substitute based on an aqueous sodium carboxymethyl cellulose (Na-CMC) solution. Rheological properties were measured in the shear-rate range relevant to industrial transport and injection systems, while sedimentation behavior was assessed using image-based analysis. The results show that the Na-CMC carrier exhibits shear-thinning behavior and viscosity levels comparable to the commercial formulation, enabling stable suspension of catalyst particles without the need for alkali additives. Unlike the reference system, the alternative carrier does not generate gas during storage, eliminating potential safety hazards associated with hydrogen evolution. Although no direct combustion experiments were performed, the obtained rheological and stability characteristics indicate that the proposed Na-CMC-based carrier is suitable for short-term storage and injection of catalyst-containing modifiers in coal dust combustion systems. Direct validation of combustion performance is planned in future work. Full article
(This article belongs to the Special Issue Recent Research on Heat and Mass Transfer)
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17 pages, 8061 KB  
Article
Simulation Study on NH3 Combustion and NOx Emissions Under Gas Turbine-Relevant Conditions
by Kumeesha Arumawadu, Braxton Wiggins and Ziyu Wang
Fire 2026, 9(1), 38; https://doi.org/10.3390/fire9010038 - 14 Jan 2026
Viewed by 255
Abstract
Ammonia (NH3) is a zero-carbon fuel and an attractive hydrogen (H2) carrier for gas turbine power generation due to its high energy density, ease of storage, and transportation. This study numerically investigates NH3/air combustion using a hybrid [...] Read more.
Ammonia (NH3) is a zero-carbon fuel and an attractive hydrogen (H2) carrier for gas turbine power generation due to its high energy density, ease of storage, and transportation. This study numerically investigates NH3/air combustion using a hybrid Well-Stirred Reactor (WSR) and Plug Flow Reactor (PFR) model in Cantera at pressures of 1–20 atm, temperatures of 1850–2150 K, and equivalence ratios (ϕ) of 0.7–1.2. The effects of pressure, equivalence ratio, and temperature on NH3 conversion and NO formation are examined. Results show that NH3 exhibits a non-monotonic conversion curve with pressure after the WSR, reaching a minimum near 5 atm, whereas NO formation decreases monotonically from 1 to 20 atm. Equivalence ratio sweeps show that NO decreases steeply as ϕ increases from 0.7 to ~1.1 as nitrogen is redirected toward N2 and oxidizer availability declines; residual NH3 increases rapidly for ϕ > 1.0, especially at high pressure. Increasing temperature accelerates NH3 oxidation and raises NO formation, most strongly at low pressure where thermal and NH/OH pathways are least inhibited. These results indicate that co-tuning pressure and equivalence ratio near rich operation enables low-NOx ammonia combustion suitable for advanced gas turbine applications. Full article
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19 pages, 4319 KB  
Article
Numerical Simulation of Tritiated Water Transfer by Moist Air in Nuclear Power Station
by Yifan Cheng, Xi Xu, Kefeng Lyu, Yang Li, Kun Hu, Yongfang Xia and Xudan Ma
Processes 2026, 14(2), 286; https://doi.org/10.3390/pr14020286 - 14 Jan 2026
Viewed by 164
Abstract
This study investigates the dispersion and condensation behavior of tritiated water vapor released into the atmosphere using moist air as a carrier, with an emphasis on safety optimization for nuclear power plant effluent discharge. A coupled heat and mass transfer model was developed [...] Read more.
This study investigates the dispersion and condensation behavior of tritiated water vapor released into the atmosphere using moist air as a carrier, with an emphasis on safety optimization for nuclear power plant effluent discharge. A coupled heat and mass transfer model was developed and implemented in CFD simulations to analyze the evolution of temperature and relative humidity during the mixing of exhaust moist air with ambient air. The effects of key atmospheric and operational parameters—including the ambient wind speed, turbulence intensity, ambient temperature, relative humidity, and exhaust velocity—were systematically examined. The results indicate that the temperature difference between the exhaust gas and ambient air is the primary factor governing condensation risk. Low wind speeds and weak turbulence favor near-field humidity accumulation, while higher wind speeds and turbulence intensities enhance mixing and dilution, thereby reducing local humidity peaks but extending the downwind impact range. Increasing exhaust velocity strengthens plume rise and long-range transport due to enhanced momentum and latent heat release, mitigating accumulation near the chimney outlet. Furthermore, high ambient temperatures significantly increase the air’s moisture-holding capacity, allowing higher exhaust humidity without inducing condensation. Full article
(This article belongs to the Section Process Safety and Risk Management)
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28 pages, 3256 KB  
Article
Comparative Analysis of Sonication, Microfluidics, and High-Turbulence Microreactors for the Fabrication and Scaling-Up of Diclofenac-Loaded Liposomes
by Iria Naveira-Souto, Roger Fabrega Alsina, Elisabet Rosell-Vives, Eloy Pena-Rodríguez, Francisco Fernandez-Campos, Jessica Malavia, Xavier Julia Camprodon, Maximilian Schelden, Nazende Günday-Türeli, Andrés Cruz-Conesa and Maria Lajarin-Reinares
Pharmaceutics 2026, 18(1), 105; https://doi.org/10.3390/pharmaceutics18010105 - 13 Jan 2026
Viewed by 302
Abstract
Background: Liposomes are attractive topical carriers, yet translating laboratory fabrication to scalable, well-controlled processes remains challenging. Objectives: We compared three manufacturing methods for diclofenac-loaded liposomes: probe sonication, microfluidic mixing, and a high-turbulence microreactor, under a Quality-by-Design framework. Methods: Differential scanning [...] Read more.
Background: Liposomes are attractive topical carriers, yet translating laboratory fabrication to scalable, well-controlled processes remains challenging. Objectives: We compared three manufacturing methods for diclofenac-loaded liposomes: probe sonication, microfluidic mixing, and a high-turbulence microreactor, under a Quality-by-Design framework. Methods: Differential scanning calorimetry (DSC) was used to define a processing-relevant liquid-crystalline temperature window for the lipid excipients. For sonication scale-up, a Plackett-Burman screening design identified key process factors and supported an energy-density (W·s·L−1) control approach. For microfluidics, the effects of flow-rate ratio (FRR) and total flow rate (TFR) were mapped and optimized using a desirability function. Microreactor trials were performed at elevated throughput. Residual ethanol during post-processing was monitored at-line by Raman spectroscopy calibrated against gas chromatography (GC). Particle size and dispersity were measured by DLS and morphology assessed by cryo-TEM. Results: DSC supported a 70–85 °C processing window. Sonication scale-up using an energy-density target (~11,000 W·s·L−1) reproduced lab-scale quality at 8 L (Z-average ~87–92 nm; PDI 0.16–0.23; %EE 86–94%). Microfluidics optimization selected FRR 3:1/TFR 4 mL·min−1, yielding ~64 nm liposomes with PDI ~0.13 and %EE ~93%. The microreactor achieved ~50 nm liposomes with %EE ~95% at 50 mL·min−1. Cryo-TEM corroborated size trends and showed no evident aggregates. Conclusions: All three routes met topical CQAs (~50–100 nm; PDI ≤ 0.30; high %EE). Method selection should be guided by target size/dispersity and operational constraints: sonication enables energy-based scale-up, microfluidics offers precise size control, and microreactors provide higher throughput. Full article
(This article belongs to the Section Pharmaceutical Technology, Manufacturing and Devices)
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9 pages, 1881 KB  
Proceeding Paper
An Assessment of Diesel Engine Performance Using a Dual-Fuel Diesel—Ammonia Injection
by Lucian Miron, Vlad-Alexandru Ungureanu, Radu Ionescu and Radu Chiriac
Eng. Proc. 2026, 121(1), 10; https://doi.org/10.3390/engproc2025121010 - 13 Jan 2026
Viewed by 256
Abstract
In the context of promoting strategies to mitigate the global warming effect resulting from greenhouse gas emissions produced by human activities, ammonia stands out as an important player in the decarbonization of various sectors, including transportation, energy, and other industries. Ammonia is an [...] Read more.
In the context of promoting strategies to mitigate the global warming effect resulting from greenhouse gas emissions produced by human activities, ammonia stands out as an important player in the decarbonization of various sectors, including transportation, energy, and other industries. Ammonia is an effective carrier of hydrogen, having three times the volumetric energy density of hydrogen itself. In this study, the authors present findings obtained from a group of experiments and simulations conducted on a diesel engine operating at a constant speed and under different loads, using a dual-fuel method in which ammonia was injected into the intake manifold to partially replace the original diesel fuel. The results demonstrate that it is possible to reduce fuel consumption and CO2 emissions. NOx dropped by 40.8% and soot by 13.4% under heavy load, while under light load, they dropped by 50.5% and 23.3%, respectively. Full article
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36 pages, 4465 KB  
Review
Earth-Driven Hydrogen: Integrating Geothermal Energy with Methane Pyrolysis Reactors
by Ayann Tiam, Sarath Poda and Marshall Watson
Hydrogen 2026, 7(1), 10; https://doi.org/10.3390/hydrogen7010010 - 13 Jan 2026
Viewed by 263
Abstract
The increasing global demand for clean hydrogen necessitates production methods that minimize greenhouse gas emissions while being scalable and economically viable. Hydrogen has a very high gravimetric energy density of about 142 MJ/kg, which makes it a very promising energy carrier for many [...] Read more.
The increasing global demand for clean hydrogen necessitates production methods that minimize greenhouse gas emissions while being scalable and economically viable. Hydrogen has a very high gravimetric energy density of about 142 MJ/kg, which makes it a very promising energy carrier for many uses, such as transportation, industrial processes, and fuel cells. Methane pyrolysis has emerged as an attractive low-carbon alternative, decomposing methane (CH4) into hydrogen and solid carbon while circumventing direct CO2 emissions. Still, the process is very endothermic and has always depended on fossil-fuel heat sources, which limits its ability to run without releasing any carbon. This review examines the integration of geothermal energy and methane pyrolysis as a sustainable heat source, with a focus on Enhanced Geothermal Systems (EGS) and Closed-Loop Geothermal (CLG) technologies. Geothermal heat is a stable, carbon-free source of heat that can be used to preheat methane and start reactions. This makes energy use more efficient and lowers operating costs. Also, using flared natural gas from remote oil and gas fields can turn methane that would otherwise be thrown away into useful hydrogen and solid carbon. This review brings together the most recent progress in pyrolysis reactors, catalysts, carbon management, geothermal–thermochemical coupling, and techno-economic feasibility. The conversation centers on major problems and future research paths, with a focus on the potential of geothermal-assisted methane pyrolysis as a viable way to make hydrogen without adding to the carbon footprint. Full article
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12 pages, 2717 KB  
Article
Photoconductive Gain Behavior of Ni/β-Ga2O3 Schottky Barrier Diode-Based UV Detectors
by Viktor V. Kopyev, Nikita N. Yakovlev, Alexander V. Tsymbalov, Dmitry A. Almaev and Pavel V. Kosmachev
Micromachines 2026, 17(1), 100; https://doi.org/10.3390/mi17010100 - 12 Jan 2026
Viewed by 412
Abstract
A vertical Ni/β-Ga2O3 Schottky barrier diode was fabricated on an unintentionally doped bulk (−201)-oriented β-Ga2O3 single crystal and investigated with a focus on the underlying photoresponse mechanisms. The device exhibits well-defined rectifying behavior, characterized by a Schottky [...] Read more.
A vertical Ni/β-Ga2O3 Schottky barrier diode was fabricated on an unintentionally doped bulk (−201)-oriented β-Ga2O3 single crystal and investigated with a focus on the underlying photoresponse mechanisms. The device exhibits well-defined rectifying behavior, characterized by a Schottky barrier height of 1.63 eV, an ideality factor of 1.39, and a high rectification ratio of ~9.7 × 106 arb. un. at an applied bias of ±2 V. The structures demonstrate pronounced sensitivity to deep-ultraviolet radiation (λ ≤ 280 nm), with maximum responsivity observed at 255 nm, consistent with the wide bandgap of β-Ga2O3. Under 254 nm illumination at a power density of 620 μW/cm2, the device operates in a self-powered mode, generating an open-circuit voltage of 50 mV and a short-circuit current of 47 pA, confirming efficient separation of photogenerated carriers by the built-in electric field of the Schottky junction. The responsivity and detectivity of the structures increase from 0.18 to 3.87 A/W and from 9.8 × 108 to 4.3 × 1011 Hz0.5cmW−1, respectively, as the reverse bias rises from 0 to −45 V. The detectors exhibit high-speed performance, with rise and decay times not exceeding 29 ms and 59 ms, respectively, at an applied voltage of 10 V. The studied structures demonstrate internal gain, with the external quantum efficiency reaching 1.8 × 103%. Full article
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26 pages, 5509 KB  
Article
Reducing Ship Emissions Through Specialized Maintenance: A Case Study Based on Real Data
by Sonia Zaragoza, Julio Barreiro Montes, Julio Z. Seoane and Feliciano Fraguela Díaz
J. Mar. Sci. Eng. 2026, 14(2), 160; https://doi.org/10.3390/jmse14020160 - 12 Jan 2026
Viewed by 205
Abstract
Maintenance operations represent one of the most underutilized opportunities to reduce emissions and improve the energy efficiency of ships. This study proposes an innovative approach that analyzes such interventions from a holistic perspective of energy, environment, and economics using real operational data from [...] Read more.
Maintenance operations represent one of the most underutilized opportunities to reduce emissions and improve the energy efficiency of ships. This study proposes an innovative approach that analyzes such interventions from a holistic perspective of energy, environment, and economics using real operational data from two liquefied natural gas (LNG) carriers before and after their maintenance operations. The results show that comprehensive actions such as complete hull and propeller cleaning can reduce fuel consumption by more than 30% and CO2 emissions by more than 15%, in addition to improving propulsive efficiency by between 18% and 34%. In contrast, minor interventions, such as underwater propeller cleaning, have a limited effect with very specific improvements in fuel savings at certain speed ranges, but no significant effect on emissions or shaft power. In particular, the study demonstrates that a single comprehensive maintenance operation can change the Carbon Intensity Indicator (CII) rating from category E to D, reinforcing the strategic role of maintenance in the decarbonization and revaluation of maritime transport. Full article
(This article belongs to the Section Marine Environmental Science)
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12 pages, 2983 KB  
Article
Characterization of a Bow-Tie Antenna Integrated UTC-Photodiode on Silicon Carbide for Terahertz Wave Generation
by Hussein Ssali, Yoshiki Kamiura, Tatsuro Maeda and Kazutoshi Kato
Telecom 2026, 7(1), 9; https://doi.org/10.3390/telecom7010009 - 12 Jan 2026
Viewed by 205
Abstract
This work presents the fabrication and characterization of a bow-tie antenna integrated uni-traveling carrier photodiode (UTC-PD) on a silicon carbide (SiC) substrate for efficient terahertz (THz) wave generation. The proposed device exploits the superior thermal conductivity and mechanical robustness of SiC to overcome [...] Read more.
This work presents the fabrication and characterization of a bow-tie antenna integrated uni-traveling carrier photodiode (UTC-PD) on a silicon carbide (SiC) substrate for efficient terahertz (THz) wave generation. The proposed device exploits the superior thermal conductivity and mechanical robustness of SiC to overcome the self-heating limitations associated with conventional indium phosphide (InP)-based photodiodes. An epitaxial layer transfer technique was utilized to bond InP/InGaAs UTC-PD structures onto SiC. The study systematically examines the influence of critical geometric parameters, specifically the mesa diameter and length between the antenna arms, on the emitted THz intensity in the 300 GHz frequency band. Experimental results show that the THz radiation efficiency is primarily governed by the mesa diameter, reflecting the trade-off between light absorption, device capacitance, and bandwidth, while the length between the antenna arms exhibits only a weak influence within the investigated parameter range. The fabricated device demonstrates strong linearity between photocurrent and THz output power up to 7.5 mA, after which saturation occurs due to space-charge effects. This work provides crucial insights for optimizing SiC-based bow-tie antenna integrated UTC-PD devices to realize robust, high-power THz sources vital for future high-data-rate wireless communication systems such as beyond 5G and 6G networks. Full article
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19 pages, 3650 KB  
Article
Impacts of Hydrogen Blending on High-Rise Building Gas Distribution Systems: Case Studies in Weifang, China
by Yitong Xie, Xiaomei Huang, Haidong Xu, Guohong Zhang, Binji Wang, Yilin Zhao and Fengwen Pan
Buildings 2026, 16(2), 294; https://doi.org/10.3390/buildings16020294 - 10 Jan 2026
Viewed by 155
Abstract
Hydrogen is widely regarded as a promising clean energy carrier, and blending hydrogen into existing natural gas pipelines is considered a cost-effective and practical pathway for large-scale deployment. Supplying hydrogen-enriched natural gas to buildings requires careful consideration of the safe operation of pipelines [...] Read more.
Hydrogen is widely regarded as a promising clean energy carrier, and blending hydrogen into existing natural gas pipelines is considered a cost-effective and practical pathway for large-scale deployment. Supplying hydrogen-enriched natural gas to buildings requires careful consideration of the safe operation of pipelines and appliances without introducing new risks. In this study, on-site demonstrations and experimental tests were conducted in two high-rise buildings in Weifang to evaluate the impact of hydrogen addition on high-rise building natural gas distribution systems. The results indicate that hydrogen blending up to 20% by volume does not cause stratification in building risers and leads only to a relatively minor increase in additional pressure, approximately 0.56 Pa/m for every 10% increase in hydrogen addition. While hydrogen addition may increase leakage primarily in aging indoor gas systems, gas meter leakage rates under a 10% hydrogen blend remain below 3 mL/h, satisfying safety requirements. In addition, in-service domestic gas alarms remain effective under hydrogen ratios of 0–20%, with average response times of approximately 19–20 s. These findings help clarify the safety performance of hydrogen-blended natural gas in high-rise building distribution systems and provide practical adjustment measures to support future hydrogen injection projects. Full article
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27 pages, 3313 KB  
Article
Weather Routing Optimisation for Ships with Wind-Assisted Propulsion
by Ageliki Kytariolou and Nikos Themelis
J. Mar. Sci. Eng. 2026, 14(2), 148; https://doi.org/10.3390/jmse14020148 - 9 Jan 2026
Viewed by 220
Abstract
Wind-assisted ship propulsion (WASP) has gained considerable interest as a means of reducing fuel consumption and Greenhouse Gas (GHG) emissions, with further benefits when combined with weather-optimized routing. This study employs and extends a National Technical University of Athens (NTUA) weather-routing optimization tool [...] Read more.
Wind-assisted ship propulsion (WASP) has gained considerable interest as a means of reducing fuel consumption and Greenhouse Gas (GHG) emissions, with further benefits when combined with weather-optimized routing. This study employs and extends a National Technical University of Athens (NTUA) weather-routing optimization tool to more realistically assess WASP performance through integrated modeling. The original tool minimized fuel consumption using forecasted weather data and a physics-based performance model. A previous extension to account for the WASP effect introduced a 1-Degree Of Freedom (DOF) model that accounted only for longitudinal hydrodynamic and aerodynamic forces, estimating the reduced main-engine power required to maintain speed in given conditions. The current study incorporates a 3-DOF model that includes side forces and yaw moments, capturing resulting drift and rudder deflection effects. A Kamsarmax bulk carrier equipped with suction sails served as the case study. Initial simulations across various operating and weather conditions compared the two models. The 1-DOF model predicted fuel-saving potential up to 26% for the tested apparent wind speed and the range of possible headings, whereas the 3-DOF model indicated that transverse effects reduce WASP benefits by 2–7%. Differences in Main Engine (ME) power estimates between the two models reached up to 7% Maximum Continuous Rating (MCR) depending on the speed of wind. The study then applied both models within a weather-routing optimization framework to assess whether the optimal routes produced by each model differ and to quantify performance losses. It was found that the revised optimal route derived from the 3-DOF model improved total Fuel Oil Consumption (FOC) savings by 1.25% compared with the route optimized using the 1-DOF model when both were evaluated with the 3-DOF model. Full article
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22 pages, 4986 KB  
Article
Towards Sustainable Energy Generation Using Hybrid Methane Iron Powder Combustion: Gas Emissions and Nanoparticle Formation Analysis
by Zakaria Mansouri and Amine Koched
Sustainability 2026, 18(2), 704; https://doi.org/10.3390/su18020704 - 9 Jan 2026
Viewed by 219
Abstract
Iron powder represents a promising carbon-free, sustainable fuel, yet its practical utilisation in combustion has not yet been realised. Achieving stable, efficient iron-only flames is challenging, and the environmental impact of hybrid iron-hydrocarbon combustion, including particle emissions, is not fully understood. This study [...] Read more.
Iron powder represents a promising carbon-free, sustainable fuel, yet its practical utilisation in combustion has not yet been realised. Achieving stable, efficient iron-only flames is challenging, and the environmental impact of hybrid iron-hydrocarbon combustion, including particle emissions, is not fully understood. This study investigates hybrid methane–iron powder flames to assess iron’s role in modifying gas and particle phase emissions and its potential as a sustainable energy carrier. The combustion of iron was investigated at both the single particle and powder flow scales. Experimental diagnostics combined high-speed and microscopic imaging, ex situ particle sizing, in situ gas analysis, and aerosol measurements using an Aerodynamic Particle Sizer (APS™) and a Scanning Mobility Particle Sizer (SMPS™). For single particle combustion, high-speed imaging revealed rapid particle heating, oxide shell growth, cavity formation, micro-explosions, and nanoparticle release. For powder combustion, at 0.5 g/min and 1.26 g/min, the experiment yielded oxidation fractions of 15.15% and 23.43%, respectively, and increased CO2 emissions by 0.22–0.35 vol% relative to methane–air flames, while NOx changes were negligible. Aerosol analysis showed a supermicron mode at ~2 µm and submicron ultrafine particles of 89% <100 nm with a modal diameter of ~56 nm. The observed ultrafine particle emissions highlight the need to evaluate health, material-loss, and fuel-recycling implications. Burner optimisation or premixed strategies could reduce CO2 emissions while enhancing iron oxidation efficiency. Full article
(This article belongs to the Section Energy Sustainability)
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