Haiwen Ge

Dedicated Hybrid Engines (DHEs) represent a paradigm shift: engine’s purpose designed to operate within electrified powertrains, enabling them to achieve brake thermal efficiencies (BTE) of 45% and beyond – a level once considered unattainable for spark ignition (SI) engines. This chapter traces the technological evolution from the classic Otto cycle to today’s highly optimized DHEs. It explains how the Atkinson/Miller cycle, combined with advanced combustion strategies such as lean burn, cooled exhaust gas recirculation, and prechamber ignition, synergize with hybrid electrification to dramatically improve efficiency. Key enabling technologies – including high compression ratio, friction reduction, thermal management, and novel ignition systems – are examined through industrial case studies. It discusses the compatibility of DHEs with carbon neutral fuels (ethanol, synthetic fuels, hydrogen, etc.), positioning them as a cornerstone of sustainable mobility well into the future. Furthermore, data oriented approach for controls is explored to tackle uncertain dynamics through physics informed neural network (PINN) to further raise the engine performance. This chapter directly addresses the book’s core themes: Internal combustion engine design – focusing on DHEs optimized for hybrid operations; combustion technologies – covering prechamber ignition, advanced ignition systems, and controls; low carbon and alternative fuels – discussing ethanol, and hydrogen; engine controls with application of PINN. The chapter builds on the authors’ industrial and academic expertise, integrates recent research, and provides a forward looking perspective that will be valuable for researchers, engineers, and policymakers.

To enhance understanding of the biotoxicity of inhaled lunar dust (LD) and safeguard astronaut health during future crewed lunar missions, we performed coarse-grained molecular dynamics simulations of nine silica nanoparticle (SiNP) aggregates─the primary component of LD─varying in size (3 and 6 nm), shape (sphere, ellipsoid, and cube), and surface features (0, 1, and 3 bulges) interacting with a pulmonary surfactant (PS) monolayer. The key findings are (1) shape, not size, governs aggregate architecture and fate: cubic SiNPs yield the most aspherical, rapidly forming aggregates and switch translocation from penetration to embedding when present as 6 nm members, and aggregation time scales as cube > ellipsoid > sphere. (2) Aggregates induce greater PS disturbance than equal-volume single SiNP, and the DPPC order parameter S_z falls to 0.678-0.706 and is driven lower (0.587-0.720) when nonspherical SiNPs dominate the aggregates. (3) Surface bulges normally hinder translocation, yet once their size and number exceed a threshold, they locally rupture the PS monolayer and shorten translocation while still increasing PS adsorption and S_z. These findings establish that aggregate morphology, rather than mass, exacerbates PS monolayer disturbance and provide quantitative benchmarks for guiding dust-mitigation strategies for future lunar missions.

Additive manufacturing (AM), also known as three-dimensional (3D) printing, has emerged as a revolutionary digital near-net-shape manufacturing technology, offering innovative solutions for the design and fabrication of complex, high-performance structures and equipment. This paper reviews the recent advancements and applications of metal AM technologies in the marine sector. Firstly, the principles and characteristics of three most widely adopted metal AM processes in this field are introduced: laser powder bed fusion (L-PBF), directed energy deposition (DED), and wire arc additive manufacturing (WAAM). Subsequently, the application status of metal AM is summarized in four key marine sectors: propulsion systems, underwater vehicle housings and structures, hull structures and shipboard equipment and components, as well as marine equipment repair and emergency support. Building on this, the major challenges for metal AM applications in the marine environment are further discussed, including the fabrication of large-scale components, standardization of materials and processes, integration of smart manufacturing and digital technologies, and sustainability and circular manufacturing. Finally, future trends are projected toward higher efficiency, intelligence, and environmental sustainability. It is indicated that metal AM will fundamentally reshape the manufacturing mode of marine equipment and support its high-performance, low-cost, intelligent and rapid-response development.

Efficient and accurate modeling of photoresist spin coating plays a crucial role in controlling film uniformity and optimizing lithography processes in semiconductor manufacturing. However, wafer-scale coating simulation remains challenging due to its high computational cost and the difficulty in resolving localized interfacial dynamics. This paper presents a two-dimensional model for simulating photoresist spin coating in an axisymmetric wedge-shaped domain. To improve both accuracy and computational efficiency, a two-dimensional adaptive mesh refinement (2D AMR) technique is developed to capture the photoresist-air interface through local mesh refinement. The proposed AMR method is capable of handling specialized wedge-shaped mesh configurations composed of pentahedral prism and hexahedral elements, which are challenging for conventional approaches. In addition, a dynamic load balancing (DLB) algorithm is introduced to improve parallel performance by mitigating workload imbalance caused by localized mesh refinement. The results show that the 2D AMR approach reduces computational effort by nearly 80% compared with full-domain uniform refinement. When combined with the DLB strategy, the computation time is further reduced by up to 65%, significantly improving simulation efficiency. The proposed approach enables efficient and accurate prediction of coating flow behavior and provides a practical computational tool for process optimization in lithography.

The expanding biomedical applications of nanomaterials have raised concerns about their inhalation toxicity. Nanoparticle (NP) interactions with the pulmonary surfactant (PS) monolayer are central to understanding this risk. Despite extensive knowledge of the interaction mechanisms between a single NP and the PS monolayer, the synergistic effects of multiple NPs on their translocation remain poorly understood. Here, coarse-grained molecular dynamics simulations were employed to systematically explore the translocation characteristics of silica nanoparticles (SiO₂NPs)─varying in size (2, 4, 6, and 8 nm), morphological complexity (spherical and cubic), and arrangement (linear and matrix)─across the PS monolayer, as well as their impacts on PS monolayer structure. The results show that (1) Morphological synergy─an increasing proportion of cubic SiO₂NPs enhances the inter-NP aggregation but reduces overall penetration ability. (2) Architectural damage signatures─matrix arrangement causes more significant damage to the PS monolayer compared to the linear arrangement, primarily manifesting as partial structural disorder and channel formation, whereas the linear arrangement is more likely to cause changes in monolayer curvature. (3) Critical size window phenomenon─two critical thresholds (α: 4-6 nm; β: 6-8 nm) define a maximum disruption zone where same-sized NP groups exert peak destabilizing effects on PS integrity. (4) Size hierarchy dominance─in SiO₂NP groups with large size disparity, larger SiO₂NPs dominate the overall behavior and significantly inhibit monolayer penetration. This work provides a systematic simulation framework for relating multi-NP architecture to translocation and PS disruption and may help generate testable hypotheses to guide future inhalation toxicology studies and nanomaterial research.

Nanosilica lunar dust (NSLD) particles pose significant respiratory hazards to astronauts, with their aggregation in the pulmonary surfactant (PS) monolayer exacerbating pulmonary nanotoxicity. However, the underlying aggregation mechanisms and translocation characteristics of NSLDs in the PS monolayer remain unclear. Here, by performing coarse-grained molecular dynamics simulations, we investigate them and consider different sizes (3 and 6 nm), shapes (sphere, ellipsoid, and cube), and morphological complexity (with and without bulges). The key findings are as follows: (1) the movement patterns of spherical and ellipsoidal NSLDs contrast with those of cubic NSLDs. Consequently, the translocation time, embedding depth, aggregation state, and penetration characteristics of aggregates composed of spherical and ellipsoidal NSLDs exhibit opposite trends to those of aggregates composed of cubic NSLDs. (2) The impact of aggregates composed of spherical and ellipsoidal NSLDs on the S_z value also contrasts with that of aggregates composed of cubic NSLDs. For PS monolayer area, aggregates containing one or two shapes of NSLDs show a decreasing trend with the number of 6 nm NSLDs increases. In contrast, when the aggregates include three different shapes of NSLDs, this trend is reversed. (3) As the number of bulges increases, the aggregation and translocation characteristics of NSLDs in the PS monolayer become more complex, exhibiting different trends depending on the specific situation. In general, the aggregation and translocation characteristics of aggregates composed of spherical and ellipsoidal NSLDs contrast with those of aggregates composed of cubic NSLDs, and the presence of bulges adds complexity to the overall behavior of these aggregates.

To understand and prevent the toxic effects of lunar dust on astronauts' health in future manned lunar exploration missions, the translocation characteristics of paired nonspherical silica nanoparticles (P-NS-SiNPs) across a pulmonary surfactant (PS) monolayer are studied using a coarse-grained molecular dynamics method considering both ellipsoidal and cubic SiNPs with/without bugles. The key findings are as follows: (1) Compared with an individual SiNP, the translocation times for 4 and 6 nm ellipsoidal P-SiNPs decrease by 25-50% and 7.7-30.7% respectively, while those for 4 and 6 nm cubic P-SiNPs increase by 428.6% and 44.4% respectively, due to cooperative effects. (2) As initial minimum distance increases, the crossing times for ellipsoidal P-SiNPs first decrease and then increase, while embedding times for cubic P-SiNPs first increase and then decrease, due to different local curvature. (3) In the combinations of ellipsoidal-coupled cubic P-SiNPs, the translocation times for the 4 nm combination decrease by 25% and 14.3% respectively, while those for the 6 nm combination increase by 30.8% and 88.9%, respectively. (4) As the number of bulges on P-SiNPs increases, the average crossing times for 4 and 6 nm ellipsoidal-type P-SiNPs increase by 40%, 20%, as well as 14.3% and 219.1% respectively, while the embedding times for 4 nm cubic-type P-SiNPs decrease by 60.8% and 68.9% respectively, and those for 6 nm cubic-type P-SiNPs increase by 80.8% and 46.2%, respectively. In conclusion, due to the differences in contact area and local curvature, the translocation characteristics of ellipsoidal and cubic P-SiNPs exhibit two opposite trends under varying situations.