Gravitasi

Effect of Magnetic Field on Germination of Purple Eggplant (Solanum melongena L) using Helmholtz Coils

Sun, 09 Jun 2024 00:00:00 +0000

Research has been carried out on the effect of magnetic field on the germination of purple eggplant (Solanus Melongena L) using Helmholtz coil. This research aims to determine the effect of exposure to a magnetic field and exposure time on the germination of purple eggplant. This study used 100 samples of purple eggplant seeds, of which 10 samples were controls (0 mT) and 90 samples were exposed to a magnetic field 0,3 mT, 0,4 mT and 0,5 mT which was divided into three exposure treatments, namely 15 minutes/day, 25 minutes/day and 35 minutes/day for 7 days. Based on the data obtained, it is proven that the strength of the magnetic field and the long exposure time have an effect on the growth and increase in the length of purple eggplant seed sprouts. The optimum magnetic field strength and exposure time is 0.4 mT and exposure time is 25 minutes/day.

Analysis of Lead Content in Cereal-Based Foods Using Atomic Absorption Spectrometer (AAS)

Sahat Maruli Tua Haloho, Idha Royani, Dita Herfiani — Sun, 09 Jun 2024 13:14:56 +0000

Cereals-based foods are foods with the highest level of consumers because they have high levels of carbohydrates. Food is also the largest contributor to heavy metal contamination that enters the human body, especially heavy metal Pb reaching 90%. Pb heavy metals with too high levels in humans can damage human organs and cause death. Research related to the analysis of heavy metal content in cereal foods, especially vermicelli has been carried out. The analysis method uses GFAAAS (Graphite Furnace Analysis Atomic Absorption Spectrometer). Some solution that must be prepared include vermicelli sample solution, working standards, and aquadem as a diluent. Based on BPOM regulation No. 5 of 2018 states that lead content in vermicelli must be less than 0.25 mg/Kg. Results indicate that First sample has an ineligible status, but second and third samples are qualified because they are negative at the time of rough determination heavy metal lead (Pb).

Subsurface Profile Mapping for Infrastructure Foundation Laying

Nurhasanah Nurhasanah, O. Ivansyah — Sun, 09 Jun 2024 13:15:30 +0000

Proper 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.

Effect of Filter and Thickness Variation on Entrance Skin Exposure (ESE) Values of Thorax Organs

Alda Saharani, Sri Zelviani, Sitti Nurrahmi, Nurul Fuadi, N. Muthmainnah — Sun, 09 Jun 2024 13:16:32 +0000

the aim of this research are to knowing the effect of using variations and thickness of Al, Cu and Pb filters on ESE values using thorax examination phantoms and to determine the effect of variations in irradiation time-current on the use of variations and thickness of Al, Cu and Pb filters on ESE values using thorax examination phantoms. The results showed that the thicker the filter used, the ESE value obtained decreased, and vice versa. While the results obtained for the irradiation time-current are the greater the time-current used, the ESE value obtained increases, and vice versa. Filters that enter the tolerance limit of thorax examination are Aluminum (Al) filters with a thickness of 1.5 mm and a time-current of 8 mAs, which is 0.089594 mGy. This is influenced by several factors including the thickness of the filter used, the irradiation time-current performed and the density of the filter.

The Identification of Aquifer Layers Using Geoelectric Resistivity Method in Jono Oge Village, Sigi Biromaru District, Sigi District

Muhammad Dahlan Th. Musa, Jamidun, Sandra Sandra, Dinda Anita Putri — Sun, 09 Jun 2024 13:17:14 +0000

Research 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.