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Subsurface Profile Mapping for Infrastructure Foundation Laying
Full text linkProper evaluation of soil layers is crucial to prevent potential construction issues. The selection of the layer for the foundation of a construction project impacts the loading, stability, and fundamental behaviour of the structure. In this study, we will map the geological structure and lithology of the subsurface layers of the earth to identify a suitable location for the foundation of infrastructure. The resistivity geoelectric method was utilized for predicting structural conditions beneath the soil's surface layer by measuring a material's specific resistance. The obtained results were refined by conducting geological and geophysical analysis. The study site's resistivity values ranged from 16.8 Ωm to 584 Ωm and were interpreted as layers of mud, sand, and gravel. The investigation determined that the suitable layers for foundation construction consist of sand and gravel situated beyond a depth of 37.06 meters beneath the surface
The Subsurface Rock Modeling with Half Slope Inversion of Reduce to the Pole Geomagnetic Anomaly in Hot Spring Natar-Lampung Area
No full textThe research in South Lampung's Natar area assesses geothermal heat source potential using the magnetic method with 89 measurement points along the Lampung-Panjang Fault line in a 3 km^2 area. Reduce To The Pole filtering enhances magnetic data accuracy. The Peter Half Slope method is employed, revealing depth ranges for different underground indicators (82.63 m to 144.25 m for very thin bodies, 61.97 m to 108.19 m for intermediate bodies, and 49.57 m to 86.55 m for very thick bodies). Geological analysis of the Lampung-Panjang fault area correlates with the Tanjungkarang Sheet Map, indicating various rock types within the Lampung Formation. The study underscores the Peter Half Slope method's effectiveness in determining subsurface anomaly depth through magnetic data
Effect of Calcination Temperature on Characteristics of Hydroxyapatite from Milkfish Bone (Chanos chanos)
Full text linkThis study investigates the synthesis of bioceramic hydroxyapatite (HAp) from milkfish bone (Chanos chanos) for medical applications. Due to its high bioactive properties and biocompatibility, HAp is becoming a main selection in biomaterials. Milkfish bone, a biological source abundant in calcium, phosphorus, and carbonate, was utilized in this study due to its high potential in the preparation of biocompatible and economical HAp. Applying various calcination temperatures, this study aims to optimize the HAp synthesis process, analyze the effect of temperature on the crystallinity, phase, and particle size of HAp, and evaluate its chemical composition and crystal structure through XRD and FTIR analysis. Results of this research are aimed to provide new solutions in the development of biomaterials from natural resources that are sustainable and biodegradable for medical applications
The Identification of Aquifer Layers Using Geoelectric Resistivity Method in Jono Oge Village, Sigi Biromaru District, Sigi District
No full textResearch has been carried out in Jono Oge Village to find out the distribution of aquifer layers after liquefaction caused by the earthquake on 28 September 2018. This research uses Automatic Array Scanning method with a total of 5 passes. Data collection was carried out on 5 tracks, with a total length of each measurement track of 240 meters. The results obtained show that the aquifer layer has a specific resistance value of 59.70 - 149.24 Ωm with a formation factor value of 2 - 5. It is thought to be an aquifer layer consisting of sand and gravel. This layer is at a depth of ± 18 – 39 m below the ground surface with a thickness of around ± 10 – 20 m, so this aquifer layer is thought to have experienced a decrease or change in depth of around ± 10 m after the liquefaction disaster
Subsurface Utility Mapping on SYT Road Segment, Yogyakarta Using Ground Penetrating Radar (GPR) Frequency 500 Mhz
Full text linkThis research was carried out aimed to detect the presence of subsurface utilities and map the utilities contained in the SYT road segment, Yogyakarta. This aims to prevent damage and leakage when planting new utilities in the future. Ground Penetrating Radar (GPR) method with a frequency of 500 MHz measure in 12 lines, processed using ReflexW. The result shows the utilities consist of cable and pipe utilities. The wires will provide a nested hyperbolic anomaly response, while the pipe provides a single hyperbole anomaly. The continuity anomaly is suspected as a utility network. The continuity is seen based on the depth and dimensions of the hyperbola are similar. The utilities contained in the SYT road segment; Yogyakarta are at a depth of 0.5 m - 2.8 m. Where there is continuity which is suspected as a cable and pipe network
Measurement of the Sound Absorption Coefficient of Rice Straw (Oryza Sativa) Acoustic Material as Noise Dampener
Full text linkThis study determines the sound absorption coefficient values of rice straw acoustic material as a noise reducer using the two-microphone impedance tube method based on ISO 10534-2:1998 standards. Two test variables were employed in this research. Composition variation consisting of three samples and thickness variation also comprising three samples. Composition variation was conducted to evaluate the ability of rice straw as a sound absorber, while thickness variation was used to determine the effect of thickness on the sound absorption coefficient of rice straw acoustic material. All test samples obtained the highest absorption coefficient values at a frequency of 1600 Hz. The acoustic material in the composition variation achieved the highest absorption coefficient values of 0.30, 0.34, and 0.37, respectively. The thickness variation obtained the highest absorption coefficient values of 0.73, 0.79, and 0.95, respectively. The obtained sound absorption coefficient values meet the standards established by the International Standardization Organization 11654
Evaluating the Stability of Red Dragon Fruit (Hylocereus polyrhizus) as Natural Dyes: Impact of Concentration, pH and Storage Duration
Full text linkThis reseach explores the application of Hylocereus polyrhizus extracts as natural dyes, emphasizing anthocyanin content, stability, and light absorption under varying conditions. The findings indicate that undiluted extracts attain maximum light absorption in the 520-550 nm spectrum, aligning with the anthocyanin pigments that impart the fruit's vivid color. Increased dilution results in diminished absorbance, attributable to reduced anthocyanin levels. The research highlights the importance of pH on pigment stability, with optimal absorption at pH 3-4, while elevated pH leads to decreased absorption due to anthocyanin structural alterations. Notably, a rise in absorbance on Day 15 of a 15-day storage period may indicate pigment stabilization, potentially through copigmentation with phenolic compounds. Nonetheless, a general decline in total anthocyanin content across samples is noted, likely influenced by environmental conditions and extraction inefficiencies. This investigation underscores the potential of red dragon fruit extracts as viable, sustainable dye sources for DSSCs and other applications
Effect of Calcination Temperature Variation on Hydroxyapatite of Cuttlefish Shell Waste (Sepia Sp.)
Full text linkThis study aims to determine the effect of calcination temperature variations on hydroxyapatite from cuttlefish shell waste. Extraction of calcium carbonate (CaCO3) into calcium oxide (CaO) using the calcination method with temperature variations 600C, 800C, and 1000C for 5 hours. The results showed that calcination temperature affects the synthesis of hydroxyapatite compounds. Based on FTIR characterization, the optimum calcination temperature is at 1000°C. Based on SEM analysis result, hydroxyapatite particles from cuttlefish shells appear homogeneous with an average particle diameter of 0.57 µm. EDX result shows that Ca/P ratio of hydroxyapatite from cuttlefish shell waste is 2.08. It can be concluded that the cuttlefish shell waste in this study can be used for biomedical applications, such us a bone implant material because it has a Ca/P ratio of more than 1 so it is not easily dissolved and can be accepted by the body
ZnO-Ag Synthesis Nanoparticles: Liquid Laser Ablation for Photocatalyst Degradation Of Textile Industrial Waste Dyes
Full text linkThe highest absorption optimization occurred in the photocatalyst degradation test under UV light. The highest percentage of photocatalyst degradation was 72.14% in the ZnO/Ag 5 sample. It was adjusted according to the FESEM results for the morphology of the ZnO/Ag nanoparticles and the crystal size on XRD. The synthesis process was carried out using a two-step method in laser ablation in liquid (PLAL). The laser method supports photocatalytic performance to degrade textile dye waste. The lowest percentage of degradation was obtained in the UV-Visible t test of 12.37% as a comparison test, the Dark test was carried out at an interval of 0 and 8 hours and observed using a UV spectrometer. The degradation resistance in the dark is 7.61% on ZnO/Ag at 8 hours
Identification of the distribution of golf mineral carrier rocks using the geomagnetic method in Pujut Lombok
Full text linkLombok Island is one of Indonesia's regions that has high gold potential. The purpose of this study was to determine the distribution and potential of rocks containing gold in Pujut, Central Lombok. The method used is geomagnetic. The results showed that the moderate geomagnetic anomaly was the response of the gold mineral host rock scattered in the center of the study area. The 2D inversion model shows that the rock layers in the study area consist of sandstone, claystone, tuff, tuff breccia, basalt, cracks, intrusions, and faults. This type of rock is thought to be a carrier of gold minerals, except for clay, basalt and breccia. The depth of the gold-bearing rock layer is 0 m to 230 m from the ground surface, with a volume of 1.22x109 m3 in an area of 12 km2. In the future it is necessary to drill and analyze the gold content.