Papers by Keyword: Density

Abstract: The increasing demand for sustainable energy solutions has intensified research into biodiesel production, which relies on chemical catalysts that have an environmental impact. This study investigates the alternative methods of biodiesel production by utilizing agricultural waste, specifically rice husk, coconut husk, and chicken manure as a catalyst for biodiesel production. Laboratory experiments were conducted to extract metal oxide from agricultural waste to be used as a catalyst in the transesterification process. The obtained ash was characterized, and it was revealed that rice husk ash contained 98% SiO₂, coconut husk ash had 72.62% of K₂O, and chicken manure ash had 46.56% CaO, with higher metal oxide compositions in each material. The transesterification reaction was conducted by varying alcohol to oil ratio from 3:1, 6:1, 9:1, and 12:1, temperature (40-80°C), catalyst concentration (1.5-4.5%wt), and reaction time (20-120min) to assess catalyst efficiency. Pure CaO was used as a control catalyst for comparison. Characterization of the produced biodiesel from all catalysts was conducted and compared to ASTM D6751 standards. The results for acid value, moisture content, density, viscosity, free fatty acid, flash point, pour point, and cloud point were analyzed and found to comply with ASTM D6751 standards. On quantity determination of produced biodiesel, the most effective catalyst was chicken manure ash with a yield of 80% and the least effective catalyst was rice husk ash with 68% yield. Using agricultural waste reduces up to 40% production cost.

Abstract: This study investigates the rheological and optical properties of sustainable palm oil-based offset printing inks, comparing four formulations with varying pigment concentrations (Palm Ink-15, Palm Ink-16, Palm Ink-17, and Palm Ink-18) against a conventional ink sample. Through rheology testing, we analyzed viscosity, yield value, and shortness to understand ink flow characteristics. Optical density measurements and colorimetric assessments in CIE L*a*b* coordinates were conducted to evaluate ink performance across different film thicknesses. The results indicate that palm-based inks exhibit a superior balance between viscosity and yield value, allowing for effective ink transfer and enhanced color saturation. Palm Ink-17, in particular, demonstrated the most rapid color intensity buildup with increased thickness, making it optimal for applications requiring rich, saturated blue tones. These findings suggest that palm oil-based inks are not only environmentally friendly but also exhibit performance characteristics suitable for high-quality offset printing applications.

Abstract: One type of hot mix asphalt that is commonly in flexible pavement types is the Asphalt Concrete - Wearing Course (AC-WC), this type of hot mix asphalt is a type of wear layer pavement which means this type of pavement is applied to the surface layer.It is regulated in the General Specifications of Bina Marga Year 2018 Revision 2. The method used is to take samples in the field, then measure the thickness of the sample. After that, laboratory tests were carried out, namely density to get density and marshal test to get quality. Then a comparison was made between the test results and the JMF plan. From the research results, it was found that there was a correlation between the thickness, density, and stability of the asphalt mixture. and the highest stability value was also obtained from the Marsal test results which were still below the specified standard.

Abstract: This study delves into the nuanced challenges of additive manufacturing, specifically focusing on the application of sinter-based processes for reactive materials, with Titanium as the focal point. The thermal debinding and sintering processes, crucial steps in shaping, are analyzed with an emphasis on the intricate control required for the removal of polymeric binders, especially concerning the reactivity of metals during these processes. Historically, the emphasis has been on materials like 316L and 17-4-PH due to their straightforward thermal debinding and sintering processes. However, the shift to Titanium and its alloys introduces complexities, requiring special debinding and meticulous control of interstitial elements such as C and O to adhere to stringent material standards such as ASTM F2885-17. This research examines the various stages of shaping progressions, addressing specific requirements like green part strength, flexibility (filaments), flowability (Metal Injection Molding), and crosslinking (Stereolithography). The focus lies on achieving thermal removal with minimal residuals and reactivity, particularly in the context of reactive metals. Lithography-Based Metal Manufacturing (LMM) and Cold Metal Fusion (CMF) emerge as significant additive manufacturing processes for small to medium-sized batches of titanium parts, utilizing sinter-based production setups. Both processes not only serve as alternatives to Metal Injection Molding but also contribute to cost-effectiveness and sustainability through the efficient reuse of unused feedstock. The selection of the optimal shaping technology for individual parts becomes critical, considering mechanical properties, final density, acceptance of interstitials, complexity, wall thickness, overhangs, and internal structures. This presentation provides a detailed analysis of Lithography-Based Metal Manufacturing, comparing it with the Cold Metal Fusion process. Key considerations include mechanical properties, surface finishes, and cost, shedding light on the technical intricacies and trade-offs inherent in each technology.

Abstract: Indonesia is a country prone to hydrological disasters, with high potentials to mud flows in some areas. The mud flows need to be channeled to the appropriate place, and the piping system is one of the best alternatives. Through this research, the analysis of flow characteristics and changes in the density concentration in two-phase (liquid-solid) fluid systems is presented. One-inch diameter transparent PVC pipe was used as the test pipe. The pressure drop, experimental friction factor, and Reynolds number on the experimental variables show an interesting relation between the variables. At 10% ratio of liquid-solid discharge, the flow discharge ranges from 0.00000800 m³/s to 0.00001817 m³/s, while at 100% ratio, the discharge reaches 0.00002133 m³/s. The ratios of liquid-solid discharge ratio of 10% to 100% have influences on increasing pressure reduction (∆P). At increasing density from 1000 to 1010 (at mixture ratios of 10% to 20%), the pressure drop (∆P) also tends to increase. At 10%, the f value ranges from 0.0005004 to 0.0011364, where the experimental friction factor tends to be lower than the theoretical friction factor.

Abstract: Strontium Calcium Titanate (Sr_0.9Ca_0.1TiO₃) ceramic powders were synthesised using a solid sintering technique and were uniaxially pressed and sintered at different temperatures of 1100 °C, 1150 °C, 1200 °C, 1250 °C, and 1300 °C for three hours. Physical, phase, microstructure and dielectric properties were studied. Perovskite Cubic Strontium Calcium Titanate phase was crystallized. With an increase in sintering temperature, the density and grain size of Sr_0.9Ca_0.1TiO₃ ceramics increased. Grain boundaries were observed in the microstructure of Sr_0.9Ca_0.1TiO₃ sintered at higher temperatures. At room temperature, the dielectric constant and dielectric loss are observed to increase with the increase in sintering temperature. AC conductivity enhanced with sintering temperature.

Abstract: Good Handling Practices (GPH) for fish will have an impact on the quality of fish catches. Therefore the addition of material as a good insulator in the hatch of a fishing vessel is needed. Polyurethane as an insulator material can be used as one of the additional materials in the hatch of a fishing vessel. This study aimed to compare the thermal conductivity properties of the composition and thickness of polyurethane. The results will find out how the influence of composition and thickness of polyurethane affect the insulation of the fishing vessel hatch. The ideal polyurethane insulation should have a material density ρ ≥ 30kg/m³. Density values from testing variations in polyurethane composition show density values in the range of 40kg/m³-100kg/m³, this outcome meets the criteria for a high-quality polyurethane insulating material.

Abstract: The purpose of this study is to investigate the influence of variations in the alkali activator to binder ratio (Al/Bi) on the workability, density, and compressive strength of geopolymer mortar. This study used an experimental approach to assess mortar compressive strength and workability utilizing a flow table in accordance with SNI 03-6825-2002, as well as mortar density in accordance with SNI 1973-2016. Variations in the Al/Bi ratio used are 0.40, 0.45, 0.50, and 0.55, with a slag content of 20% and a ratio of sodium silicate to sodium hydroxide (SS/SH) 1.5. The materials used in this research are fly ash type F, slag, fine aggregate, and an alkali activator consisting of sodium hydroxide (SH) and sodium silicate (SS). The specimen is in the shape of a cube with dimensions of 50x50x50 mm and a total of 16 test objects. The results show that the higher the Al/Bi ratio, the workability of the geopolymer mortar increases, but the density decreases. The higher the Al/Bi ratio, the compressive strength of the geopolymer mortar increases to an optimal Al/Bi ratio of 0.50. At an Al/Bi ratio of 0.40, it has workability in accordance with SNI 03-6825-2002 standards. All variations of the Al/Bi ratio produce density that meets the SNI 1973-2016 standards. The maximum compressive strength of the geopolymer mortar was 12.15 MPa at an Al/Bi ratio of 0.50.

Abstract: This research was carried out to compare the performance of ANFO and Ammonium Nitrate on fragment size distribution by using the ANFO and AN as the column charge in blasting operations, measuring the fragmentation size after each blasting operation, characterizing the fumes evolving from the blasting operation in each case and compare the performance of the ANFO and AN. The densities of the rock deposit were derived as 2.638 g/m³ and 2.622 g/m³ for Block A and Block B respectively. The rebound hardness tests ranged from 47 to 61 for Block A and Block B from 48 to 54. The total explosive charge used for each of the blocks was 0.1 kg. The muckpile magnification ratio for Block A was 0.008 and Block B was 0.004. The fragmentation sizes for Block A range from 1.869 cm to 19.411 cm and Block B from 2.414 cm to 37.177 cm. The magnification ratio and fragment sizes show that Block A has better fragmentation than Block B. Ammonia gas was not present in the area of study before blasting but the fume emitted after first blasting with ANFO produced 0.08% of Ammonia gas and after the second blasting with AN 0.07% were produced. The oxygen level was reduced from 20.9% before blasting to 19.2% after the first blasting and 19.1% after the second blasting. It was deduced that blasting with ANFO generated more Ammonia gas than blasting with AN but the Oxygen level when ANFO is used was higher than when AN is used. Keywords: Blasting, density, explosive, fragmentation, magnification ratio

Abstract: Abstract. Much trash, similar to clay bricks, concrete, and mortar, is made when things are built or torn down. A cheap and eco-friendly way to eliminate this trash is to recycle it into new building materials. Construction and removal waste is turned into recycled aggregates after being smashed, ground, dried, and graded. This paper shows the findings of a study that looked into using crushed bricks as aggregates. The bricks were taken from the demolition of different places and then crushed until they were no bigger than 10 mm. Micro steel fibres (1% by volume of the concrete) and crushed bricks (25% and 50%) of the original reactive powder concrete were added to the mix instead of fine sand and micro steel fibres before the casting. To look into several properties of the standard and reactive powder concrete, including their density, compressive strength , and Flexural strength . compressive strength of modified reactive powder concrete ( MRPC) with 25% crushed bricks increased by 7.22% and 6.73% more than compressive strength of the standard reactive powder concrete at age 7 days and 28 days of testing respectively and Flexural strength increasing by 33.96%and 27.6% more than Flexural strength of the standard reactive powder concrete at age 7 days and 28 days of testing respectively . The compressive strength slightly decreasing by 8.43% and 7.69% at age 7 days and 28 days of testing respectively when 50% crushed bricks were used instead sand and Flexural strength decreasing by 16.03% and 14.92% less than reference mixture when 50% crushed brick incorporated. Moreover, modified reactive powder concrete was less dense than the reactive powder concrete that was first made.