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This research aims to determine the development of the number of scientific publications in the field of particulate matter; the number of publications from each country that publish articles on heat transfer, nanoparticles, and automotive radiators; articles with the highest number of citations; and visualization publication development map based on keywords. To achieve this goal, quantitative descriptive research was carried out using bibliometric analysis with the help of the publish or perish (PoP) application to collect data and VOSviewer to visualize related research topics. The article data taken is limited to 2018-2023. In addition, the terms heat transfer, nanoparticles, and automotive radiators are used as keywords in collecting article data using the pop application. Research on heat transfer, nanoparticles, and automotive radiators has increased in 2020 and India has become one of the countries that has contributed many publications on this topic. From the mapping results, research on heat transfer, nanoparticles, and automotive radiators is still being carried out frequently, especially in early 2020-2021. This research can help academics determine which problems to research and can be used as a reference for further research.

This study aims to develop asbestos-free and environmentally friendly brake pads using apus bamboo powder (Gigantochloa apus). In the experiments, bamboo powder, resin, and catalyst were used as the raw materials and varied to ensure the quality of the prepared brake pads. To analyze the performance of brake pads, the fabricated brake pads are subjected to physicochemical tests (such as microscopic tests and functional group analysis) and mechanical tests (such as puncture tests, compression tests, and friction tests). The research results showed that adjusting the composition of the raw materials allowed a change in the performance of the brake pad, including porosity, morphological structure, and mechanical properties. Indeed, the condition of the low porosity on the inside of the brake pad strategically optimizes the compression strength of the material, making this design ideal for applications that require high resistance to compression loads. This study shows the possibility of apus bamboo powder as an alternative to asbestos in the production of non-asbestos brake pads, offering a safer and environmentally friendly solution as well as giving ideas for supporting current issues in the sustainable development goals (SDGs).

This study aimed to comprehensively analyze particulate matter (PM) emissions from vehicles, focusing on their sources based on combustion and non-combustion process, classification (PM10, PM2.5, PM0.1), and health implications (including PM transportation into lungs). Employing bibliometric analysis, we assessed the growth of scientific publications related to PM, identifying top-cited works based on citations, publisher, author, country, and affiliation. We also visually mapped the development of research in this field using keyword-based publication data from Scopus (2019-2023) with the keywords "particulate matter", "emission”, and "particle size" by utilizing Publish or Perish and VOSviewer software. Our findings underscore a significant uptrend in particulate matter research, shedding light on key areas of investigation. This study serves as a valuable resource for academics seeking research direction and a reference point for future investigations.

The purpose of this study was to determine the effect of silver nanoparticles (AgNPs) from different green synthesis medium and their various particle sizes on antibacterial activity. The article review method compares the results of 11 studies obtained from the PubMed database, Web of Science, and ScienceDirect indexed by Scopus in the last five years. The search was conducted based on the phrases nanoparticles, antibacterial, Green synthesis, and AgNPs. Green synthesis of AgNPs with various plant extracts produces different sizes of nanoparticles. The smallest size AgNPs were obtained in the range of 5-15 nm and an average of 13 nm extracted using the leaves of the Pacific Yew tree (Taxus brevifolia). Meanwhile, AgNPs with the best antibacterial effectiveness were obtained from the Blume flower extract (Wedelia urticifolia) measuring less than 30 nm providing a zone of inhibition for S. aureus, K. pneumoniae, E. coli, and P. aeruginosa bacteria.

The purpose of this study was to analyze the effect of a resin composition on the performance of brake pads with durian seeds (BDs) as the base material. Experiments were done by attaching saw-milled BD particles to a polymer matrix. Various resin compositions were used for preparing the brake pad, which was then tested (press test, puncture test, and friction test). Physical properties (i.e., particle size, surface roughness, morphology, and density), as well as mechanical properties (ie: hardness, wear rate, and friction coefficient properties), were investigated. Based on observations, the best mechanical properties were found in the highest resin mixture, reaching a compressive strength value of 2.4 MPa. The impact of the homogeneity of the brake pad filler particles is the main reason. The high resin composition causes more cross-links to be formed. This research demonstrates the prospective environmentally friendly and inexpensive brake pads used to replace current products that use hazardous materials.

This study aims to demonstrate the preparation of carbon microparticles obtained from red dragon fruit peel waste and their adsorption isotherm characteristics. The carbon microparticles were prepared by combining carbonization (at 250°C) and saw-milling process, and to get carbon microparticles with a specific size, sieve analysis was used. The adsorption isotherm was done by testing the adsorption ability of carbon microparticles with a specific size into curcumin solution in the batch-type reactor. The adsorption results were then compared to several standard isotherm models (i.e., Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models) for understanding what phenomena happen during the adsorption process. The adsorption analysis was also confirmed by testing several sizes of the carbon microparticles to predict the proposal mechanism in the adsorption process. The analysis results showed that the multilayer adsorption process occurs for all sizes in the micrometer range, and the process involves physical interactions between adsorbate and surface of adsorbent. The existence of multilayers is due to the possibility in the existence of porous structure in the carbon microparticles. This study is important for giving an alternative solution for reusable organic waste as well as supporting the fundamental researches in the further applications of carbon particles as catalyst and adsorbent.

This paper aims to evaluate the economic feasibility of Fe 3 O 4 nanoparticle production from a laboratory scale to an industrial scale feasibility. The evaluation was conducted using 2 models of feasibility studies, namely: technical analysis and economic evaluation. Technical analysis provides information on the potential for large-scale production and the results of this process can be applied using commercially available and inexpensive equipment. Economic evaluation is based on a comparison of the Cumulative Net Present Value graph in an ideal condition and the graph when parameters changing are made (such as changes in the dollar exchange rate, the quantity of sales products, and the value of employee salaries). From the evaluation results, all parameter changes give a positive value indicating that the project is feasible to run commercially and on a large scale. This is because the evaluation results provide a stable index of profit for some changes in parameter values. This study shows that Fe 3 O 4 fabrication can provide promising profits in developing countries and can attract foreign investors to work together on Fe 3 O 4 fabrication.

The purpose of this study is to analyze the production of copper nanoparticles (Cu NPs) on an industrial scale in an engineering perspective and economic evaluation perspective. Energy is needed because of various energy related applications. Evaluation of Cu nanoparticle production in an engineering perspective is carried out from the selection of processes that are adapted to industrial scale, calculation of mass balance, to the adjustment of commercially available equipment. Evaluation of production from an economic point of view is done by calculating economic parameters: Gross Profit Margin, Internal Return Rate, Payback Period, Cumulative Net Present Value, Profitability Index, and Break Even Point. Briefly from the production process, we use Copper acetate hydrate (CuAc2.2H2O) (as a source of Cu), Tween 80 (polyoxyethylene-(80)-sorbitan monooleate) and ethylene glycol (as a reducing agent). The engineering viewpoint shows this process is capable of producing Cu nanoparticles which can be used as conductive nanoionic. Economic evaluation determines the process is beneficial, discussing with positive values ​​all economic parameters. However, for some variations this process is not profitable, so economic evaluation is needed.

Indonesia has an abundance of biomass from agricultural, plantation, and domestic waste products. Biomass can be converted into fuels and chemicals that are environmentally friendly. Empty fruit bunches (EFB) are biomass from abundant palm oil processing. Pyrolysis was a thermal process with free oxygen at temperatures between 400-600°C. Generally, pyrolysis was carried out under fast pyrolysis to produce a product that leads to bio-crude oil. One of the main components of bio-crude oil was phenol, which had been produced from further processing of crude oil. With the limitations of crude oil, the production of phenol from biomass pyrolysis was an option for the future, especially for fuels and fuel additives. Thus, it is necessary to investigate the effect of heating rate, temperature pyrolysis, and holding time on pyrolysis products including phenols in bio-crude oil. Slow pyrolysis of EFB was performed at various parameters, including temperatures (400, 450, and 500°C) and holding time (5, 10, and 15 min). Slow pyrolysis of oil palm EFB with variations in temperature and holding time has been carried out by producing liquid between (40 - 42 %weight), gas (19 – 21 % weight), and solid products (38 – 39 % weight). Biocrude oil liquid product showed the highest yield compared to biochar and bio pyrolysis gas. Temperature plays an important role in controlling the production of bio-crude oil as a liquid product, including a component in bio-crude oil. Phenol recovery was more affected by temperature instead of holding time.

A brake pad is the most crucial component in motorized vehicles. Many ways have been done and reported on how to prepare resin-based brake pads, but information relating to the economic analysis of resin-based brake pads on a large-scale production is still rare. This study aimed to report a literature review of brake pad production from biomass and agricultural wastes, optimal design of brake pad, and techno-economic analysis of resin-based brake pad production from rice husk. This study was also completed with a literature review on brake pad production using agricultural waste and current reports on techno-economic analysis. In the techno-economic analysis, we focused on engineering and economic perspectives. Engineering analysis was conducted by calculating the mass balance in the resin-brake pad production process. To support the analysis, economic parameters including gross profit margin (GPM), payback period (PBP), break-even point (BEP), cumulative net present value (CNPV), profitability index (PI), internal rate return (IRR), and return on investment (ROI) were calculated to predict the feasibility of project under ideal condition. We also calculated the techno-economic analysis for the worst cases in the project, calculating the internal problems (i.e., raw materials, sales, utility, labor, employee, fixed cost, variable cost, and production capacity) and the external issues (i.e., taxes and subsidiaries). Based on the engineering evaluation, the resin-based brake pad project is perspective. From economic evaluation, GPM, PBP, BEP, CNPV, PI, IRR, and ROI showed positive results, indicating that the project is perspective in the large-scale production. This work has demonstrated the importance of the projects for further development and can be used as a reference for further production of brake pads made from agricultural waste.

This study aims to investigate the effect of rice husks’ particle size on resin-based brake pad performance (i.e. compressive strength, puncture strength, mass loss, wear rate, friction coefficient, and heat resistance). Bisphenol A-epichlorohydrin and cycloaliphatic amine were mixed to form resin and used as the brake pad's base material. In the experiment, rice husk with a specific particle size (i.e., 250, 500, dan 1000 μm) was added to the resin. Rice husk has received considerable interest due to its lignin, cellulose, and silica content, making it suitable as friction material due to its ceramic-like behavior. The experimental results showed small rice husk particles improved compressive strength, puncture strength, and bulk density. This can be obtained from the analysis of the maximum compressive strength for brake pad supported by particles with sizes of 250, 500, and 1000 μm having values of 0.238; 0.173; and 0.144 MPa, respectively. In contrast, large particles formed coarse surfaces and pores, decreased mass loss rate, and improve friction properties (i.e. wear rate, friction coefficient). The friction coefficient values of brake pad supported by particles with sizes of 250, 500, and 1000 µm were, respectively, 0.2075; 0.2070; and 0.3379. Particle size affected interpacking, interfacial bonding, pores number and size, thermal softening, mechanical properties, and friction properties of the brake pad. Comparison between the prepared resin-based and commercial brake pad was also done, confirming the utilization of agro-waste as a potential alternative for friction material in the brake pad.