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Recent studies have shown the potential of zinc oxide as an additive in diesel engines because of its favorable properties. Goethite, as a metal additive, exhibits good thermodynamic stability and acts as a catalyst carrier to reduce environmental pollution. Incorporating zinc oxide microparticles and goethite nanoparticles into pure palm oil (PPaO) has great potential to improve the fuel properties. Therefore, in this study, the effects of adding zinc oxide microparticles and goethite nanoparticles into PPaO on the engine performance, spray characteristics, and smoke opacity of a diesel engine were investigated. A high-speed camera was used for the spray experiments. The results showed that the use of PPaO significantly increased the smoke opacity by ∼127.89 % compared with diesel fuel (DF). However, the use of PPaO with zinc oxide microparticles (PPaOZnO) and PPaO with goethite nanoparticles (PPaOGOE) significantly reduced the smoke opacity. The reduction in smoke opacity was most pronounced for the PPaOGOE fuel blend, with a value of 60 %, relative to the smoke opacity for DF. The PPaOZnO fuel blend significantly increased the specific fuel consumption by 37.1 %, with an average increase of ∼24.21 %, compared with DF at an engine load of 40 %. Moreover, the use of PPaOZnO and PPaOGOE fuel blends improved spray penetration 2 times compared to PPaO, although the relative viscosity and spray angle were similar to those for PPaO. These findings suggest that zinc oxide and goethite have great potential as additives for PPaO fuel, thereby enhancing the efficiency and performance of diesel engines.

Fuel additives are recognized for their potential to make diesel engines cleaner and more efficient. However, the use of Pure Palm Oil (PPaO) as a fuel faces challenges due to its inherent combustion inefficiencies. This study explores how Acetylene Black (AB), as an additive, affects the combustion performance and spray characteristics of a diesel engine. Observations of spray phenomena were conducted using a High-Speed Camera Phantom C110. The addition of AB to PPaO resulted in an increase in engine power and torque by 11.43 % at a 60 % load, averaging a 2.97 % improvement over diesel fuel (DF). PPaO demonstrated the most significant improvement in Specific Fuel Consumption (SFC) by 17.2 % at a 40 % load, averaging an 8.2 % increase. For PPaO with AB (PPaOAB), the greatest enhancement in SFC occurred at a 10 % load, showing a 9.2 % improvement over DF, with an average increase of 2.1 %. The study also found that thermal efficiency was optimally enhanced with PPaOAB at a 20 % load, achieving a remarkable 17.7 % improvement compared to DF. Notably, the inclusion of PPaOAB significantly reduced the thickness of carbon deposits on the pistons and cylinder head by 51.8 % and 3.9 %, respectively, and improved spray angle and penetration compared to PPaO. These findings suggest that AB could be a promising additive for PPaO, sparking further research interest in the application of AB in other fuels.

As one of the largest sources of CO2 emissions, the integration of non-carbon fuels in coal-fired power plants will significantly impact the global decarbonisation strategy. Hydrogen is a potential non-carbon fuel, and ammonia is a promising hydrogen carrier fuel. In this study, the effect of ammonia co-firing in a low-rank coal-fired power plant is thermodynamically modelled and evaluated in Aspen Plus V12.1. The integrated co-firing system is modelled in two different cases. The first case is made to maintain the combustion process, resulting in constant excess oxygen content in the flue gas. The second case is to minimise the fan modification in the power plant by maintaining the maximum air flow rate. The results show that increasing fraction of ammonia reduced CO2 and SOx emissions due to the decreasing coal fraction. NOx emission proportionally changes with the furnace temperature, which increases at constant excess oxygen case and decreases at constant airflow case. It was also shown that both cases’ boiler efficiency is relatively similar on the same ammonia fraction. The thermodynamic analysis provides an initial assessment of the implementation of ammonia co-firing in coal-fired power plants as an effort of decarbonisation in the energy sector.

Growing attention to the environmental aspect has urged the effort to reduce CO2 emission as one of the greenhouse gases. The cement industry is one of the biggest CO2 emitters in this world. Alternative fuel is one of the challenging issues in cement production due to the limited fossil fuel resources and environmental concerns. Meanwhile, hydrogen (H2) has been reported as a promising non-carbon fuel, with ammonia (NH3) as the main candidate for chemical storage methods. In this work, an integrated system of cement production with an alternative H2-based fuel is proposed, consisting of the dehydrogenation process of NH3 and the H2 combustion to provide the required thermal energy for clinker production. Different catalysts are employed and evaluated to analyze the specific energy input (SEI). The result shows that the conversion rate strongly determines the SEI, with minimum SEI (3829.8 MJ t-clinker−1) achieved by Ni-Pt-based catalyst at a reaction temperature of 600 ºC. Compared to the conventional fuel of coal, the H2-based integrated cement production system shows a significant decrease of 44% in CO2 emission due to carbon-free combustion using H2 as the fuel. The current study on the proposed integrated system of H2-based cement production also provides an initial thermodynamic analysis and basic observation for the adoption of non-carbon-based H2, including the storage system of NH3, in the cement production process.

Floating solar still is a suitable technology for remote or rural coastal area applications. The device should be made of low-cost materials available locally to provide more access to the broader community. However, the low-cost materials usually do not have the best physical properties, decreasing the overall solar still performance. This work demonstrated a low-cost floating solar still prototype entirely made of locally available materials. To further understand the influence of different parameters on the solar still performance and guide the prototyping process, we also performed the system's heat and mass transfer analysis. Our experimental results indicate a high absorber temperature (59.5 °C), even on a cloudy day. Our model also fits the temperature measurement reasonably. However, the recorded overall efficiency still suffers mainly due to the collection system, which decreases the overall performance; an example of a practical challenge, which is often overlooked but plays a crucial role in increasing the readiness level of the prototype.

In the last decades of electric vehicle (EV) development, battery thermal management has become one of the remaining issues that must be appropriately handled to ensure robust EV design. Starting from researching safer and more durable battery cells that can resist thermal exposure, battery packing design has also become important to avoid thermal events causing an explosion or at least to prevent fatal loss if the explosion occurs. An optimal battery packing design can maintain the battery cell temperature at the most favorable range, i.e., 25–40 °C, with a temperature difference in each battery cell of 5 °C at the maximum, which is considered the best working temperature. The design must also consider environmental temperature and humidity effects. Many design strategies have been reported, including novel battery pack constructions, a better selection of coolant materials, and a robust battery management system. However, those endeavors are faced with the main challenges in terms of design constraints that must be fulfilled, such as material and manufacturing costs, limited available battery space and weight, and low energy consumption requirements. This work reviewed and analyzed the recent progress and current state-of-the-art in designing battery packs for superior thermal management. The narration focused on significant findings that have solved the battery thermal management design problem as well as the remaining issues and opportunities to obtain more reliable and enduring batteries for EVs. Furthermore, some recommendations for future research topics supporting the advancement of battery thermal management design were also discussed.

In the roadmaps of the automotive industry, the electric vehicle (EV) is regarded as a crucial technology for the future of automotive power systems. The EV has become a top priority of major global car manufacturers and is expected to disrupt the road transportation sector. In Malaysia and Indonesia, EVs just started as an important force. However, in Malaysia, the lack of EV infrastructure, along with its strong dependency on fossil fuels, poses an enormous challenge. The situation is very similar in Indonesia. Indonesia has huge potential as Southeast Asia’s largest vehicle market and a major nickel producer, an important EV battery ingredient. Therefore, this article addresses several critical issues in implementing EVs in Malaysia and Indonesia. In preparing this review, we have thoroughly selected very important EV keywords that are frequently asked. We have also interviewed some prominent figures in the field of EV to address the most critical aspects worth including in the paper. In doing so, we plan to provide content that will be beneficial not only to the academic world but also to the automotive industry in general. Firstly, a summary of the EV adoption scenario in each country was presented. Afterwards, the types of EVs and battery capacities available in both countries were explained. The next section focused on the adoption rate of EVs, followed by the discussion of EVs charging infrastructure. In addition to that, issues pertaining to vehicle tax credit were also addressed. The opportunities and challenges of EV were then addressed in depth before concluding remarks were given.

Most of the highly efficient luminescent silicon nanocrystals (SiNCs) reported to date consist of organically capped silicon cores. Here, we report a method of obtaining Si/SiO2 core/shell nanoparticles emitting at a peak energy of 1.5 eV with very high quantum yields (53–61%). The same method led to quantum yields of ~30% for porous silicon powder emitting at 1.9 eV. The SiNCs were very stable under continuous excitation for several hours. The lifetime at 1.5 eV was over 232 μs, the longest ever reported for SiNCs, consistent with the very high luminescence efficiency. The SiNCs were first fabricated by non-thermal plasma synthesis or anodization in the case of porous silicon. Then, a thin oxide shell (~1 nm) was grown using high-pressure water vapor annealing. This oxidation process allows for the growth of very good quality oxide with low defect concentration and low stress, resulting in very good surface passivation, which explains the very high quantum yields obtained.

A design for the fail-safe mechanism of a guide vane in a Francis-type hydro turbine is proposed and analyzed. The mechanism that is based on a shear pin as a sacrificial component was designed to remain simple. Unlike the requirements of conventional designs, a shear pin must be able to withstand static and dynamic loads but must fail under a certain overload that could damage a guide vane. An accurate load determination and selection of the shear pin material were demonstrated. The static load for various opening angles of the guide vane were calculated using the computational fluid dynamics Fluent and finite element method Ansys programs. Furthermore, simulations for overload and dynamic load due to the waterhammer phenomenon were also conducted. The results of load calculations were used to select an appropriate shear pin material. Quasi-static shear tests were performed for two shear pins of aluminum alloy Al2024 subjected to different aging treatments (i.e. artificial and natural aging). The test results indicated that the Al2024 treated by natural aging is an appropriate material for a shear pin designed to function as a fail-safe mechanism for the guide vanes of a Francis-type hydro turbine.

Silicon-based nanostructured materials have been studied to utilize and observe the novel properties of silicon nanoparticles (SiNPs). Nonthermal plasma was employed to synthesize SiNPs, producing particles below 10 nm with narrow size distribution. The synthesis process of nonthermal plasma is discussed including the parameters that determine the particle size, yield and crystallinity of SiNPs. In this study, nanostructured material of SiNP/polystyrene (PS) nanocomposite has been observed to have a significant decrease in thermal conductivity. In this paper, post-processing of thermal annealing was applied, and the thermal conductivity measurement result shows the increase of thermal conductivity values. Although there is no significant enhancement of SiNP dispersion in the PS matrix, the thermal annealing induced molecular structure change, resulting in thermal transport enhancement at the interfacial region. The preservation of unique properties of nanoscale materials and low-cost fabrication by a silicon ink process at room temperature provide the promising potential of the SiNP-based nanostructured material. In addition, the combination of interfacial region engineering and post-processing provides controllable thermal transport properties for application in heat transfer management. [ABSTRACT FROM AUTHOR]

Silicon nanocrystals (SiNCs) are well known for their size-dependent optical and electronic properties; they also have the potential for low yet controllable thermal properties. As a silicon-based low-thermal conductivity material is required in microdevice applications, SiNCs can be utilized for thermal insulation. In this paper, SiNCs and polymer nanocomposites were produced, and their thermal conductivity, including the density and specific heat, was measured. Measurement results were compared with thermal conductivity models for composite materials, and the comparison shows a decreasing value of the thermal conductivity, indicating the effect of the size and presence of the nanostructure on the thermal conductivity. Moreover, employing silicon inks at room temperature during the fabrication process enables a low cost of fabrication and preserves the unique properties of SiNCs. [ABSTRACT FROM AUTHOR]