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Sintesis dan Karakterisasi Material Beton Hidrofobik dan Self Healing Berbasis Mikroorganisme Maulida, Yulia; Ratnawulan; Riri Jonuarti; Amir, Harman
Jurnal Penelitian Pendidikan IPA Vol 9 No 12 (2023): December
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v9i12.5841

Abstract

The high water absorption of concrete causes the concrete to easily experience cracking and damage. One way to increase the durability of concrete is by adding microbes which can fill the micro cavities in the concrete with the resulting Calcium Carbonate (CaCO3) deposits. However, the weakness of using microorganisms is that they are unable to withstand high hydration heat. Therefore, by varying the temperature in this research, it is possible to determine the effect of the metabolism of the bacteria produced. This research was carried out to avoid damage by creating a hydrophobic and self-healing layer which helps increase the durability and strength of the concrete. The concrete sample made resembles a cube measuring 5 cm x 5 cm x 5 cm. The manufacturing materials are Portland cement, Otawa sand, distilled water and a mixture of E. coli bacteria. Heating was carried out using an oven at temperatures of 30, 60, 90, and 120 oC. Characterization testing was carried out using a Cpmreson machine, XRD and contact angle testing.
Pengaruh Komposisi Nanosilika Terhadap Kinerja Mekanik Aspal Hibrida Berbasis Mikroorganisme Muhamad Khalid Khadafi; Ratnawulan, Ratnawulan; Riri Jonuarti; Syafri, Syafri
Journal of Science, Technology, and Innovation Vol 1 No 3 (2026): : April: Inventa: Journal of Science, Technology, and Innovation
Publisher : CV SCRIPTA INTELEKTUAL MANDIRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.65310/d4fyrk95

Abstract

The decline in pavement performance due to increasing traffic loads necessitates the development of advanced materials beyond conventional asphalt mixtures. This study investigates the effect of nanosilica composition on the mechanical performance of hybrid Asphalt Concrete-Wearing Course (AC-WC) modified with Escherichia coli as a biomineralization agent. The mixture was prepared using a fixed asphalt content of 6% and nanosilica variations of 0%, 3%, 5%, and 9% by asphalt weight, combined with bacterial concentration of 10³ cells/mL. Marshall testing was conducted in accordance with Bina Marga 2018 Revision 2 specifications. The results indicate that nanosilica addition leads to a gradual decrease in density from 2.472 to 2.453 g/cm³, while significantly increasing stability from 1,094 kg to 1,560 kg. Flow values ranged between 3.90 and 4.20 mm, with higher compositions exceeding specification limits. The 5% nanosilica composition demonstrated the most balanced performance across all parameters. The synergistic interaction between nanosilica and bacterial activity enhances interparticle bonding, offering a promising approach for developing durable and sustainable asphalt materials.
Pengaruh Variasi pH HCL dalam Pengasaman Montmorillonit Terhadap Hasil Bleaching Crude Palm Oil Tiara Fatika Sari; Riri Jonuarti
Journal of Science, Technology, and Innovation Vol 1 No 3 (2026): : April: Inventa: Journal of Science, Technology, and Innovation
Publisher : CV SCRIPTA INTELEKTUAL MANDIRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.65310/hjv1kg76

Abstract

Crude Palm Oil (CPO) requires a bleaching process to reduce pigments and free fatty acids (FFA). Montmorillonite as an adsorbent needs acid activation to improve its adsorption capacity. This study aimed to investigate the effect of HCl activation at pH 2, 4, and 6 on the surface morphology of montmorillonite as characterized by Scanning Electron Microscopy (SEM) and its influence on CPO bleaching efficiency. Acid activation was performed using 0.01 M HCl with a slurry titration method. Particle size analysis was conducted using ImageJ software with the length parameter. Results showed that unactivated montmorillonite had a mean particle length of 1054.54 nm with dense and agglomerated morphology. Activation at pH 4 produced the most homogeneous particle distribution with a mean length of 1635.57 nm and a more open surface structure. Bleaching analysis demonstrated that montmorillonite activated at pH 4 generated the lowest FFA content of 1.4% compared to pH 2 and pH 6. These findings indicate that pH 4 activation provides the optimum balance between structural stability, pore opening, and adsorption effectiveness for CPO bleaching.    
Pengaruh Pelapisan Kaolin Pada Titanium Dioksida (TiO2) dan Zinc Oksida (ZnO) Terhadap Aktivitas Fotokatalitik Lapisan Tipis Okta Khairina; Riri Jonuarti
Journal of Science, Technology, and Innovation Vol 1 No 3 (2026): : April: Inventa: Journal of Science, Technology, and Innovation
Publisher : CV SCRIPTA INTELEKTUAL MANDIRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.65310/zmkk4495

Abstract

Titanium dioxide (TiO₂) and zinc oxide (ZnO) are widely applied as broad-spectrum ultraviolet protective agents; however, nanoscale modification that improves optical transparency may simultaneously increase photocatalytic activity and reactive oxygen species (ROS) generation. This study investigated the effect of kaolin coating on the photocatalytic behavior of TiO₂ and ZnO thin films fabricated through spin coating. Nanoparticles were reduced to sizes below 150 nm using high-energy ball milling and deposited into sandwich-structured nano-kaolin/TiO₂ and nano-kaolin/ZnO films with weight ratios of 0%:100% and 50%:50%. Photocatalytic performance was evaluated through methylene blue degradation under ultraviolet irradiation for 5 h at 664 nm. Pure TiO₂ and ZnO exhibited high photocatalytic degradation efficiencies of 72.77% and 68.51%, respectively. Incorporation of 50% kaolin significantly reduced degradation efficiencies to 22.10% for TiO₂/kaolin and 23.69% for ZnO/kaolin. Kaolin contributed to initial physical adsorption while suppressing ROS formation through active-site coverage and controlled charge-transfer pathways. The resulting sandwich-structured thin films demonstrated improved optical stability, reduced photocatalytic aggressiveness, and promising potential as multifunctional UV-protective nanomaterials for safer sunscreen-related applications.    
Pengaruh Jenis Asam Mineral Pada Sintesis Acid Activated Montmorillonite Terhadap Struktur, Morfologi, dan Performa Bleaching Earth Hanifah Sriamelia; Riri Jonuarti
Journal of Science, Technology, and Innovation Vol 1 No 3 (2026): : April: Inventa: Journal of Science, Technology, and Innovation
Publisher : CV SCRIPTA INTELEKTUAL MANDIRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.65310/qjnaem59

Abstract

Montmorillonite (MMT) is a clay mineral belonging to the smectite group, characterized by a large surface area, high cation exchange capacity, and a layered structure, making it a promising bleaching earth for palm oil refining. However, natural montmorillonite exhibits limitations, including a low number of active sites and limited porosity, thus requiring acid activation to enhance its performance. This study aims to analyze the effect of different mineral acids on the crystal structure, morphology, and bleaching performance of acid-activated montmorillonite. Activation was carried out using HCl, H₂SO₄, HNO₃, and H₃PO₄ at a concentration of 1 M for 3 hours. Characterization was conducted using X-ray diffraction (XRD) to determine crystallinity, scanning electron microscopy (SEM) to observe surface morphology, and UV–Vis spectrophotometry to evaluate bleaching performance. The XRD results revealed that sulfuric acid produced the largest crystal size (78.8 nm) with the highest degree of homogeneity. Activation with HCl resulted in a crystal size of 64.5 nm, H₃PO₄ yielded 68.3 nm, and HNO₃ produced 68.5 nm. SEM analysis showed the formation of new pores and a rougher surface texture after activation. HCl activation yielded the most favorable surface morphology. Bleaching tests demonstrated a significant reduction in color intensity and β-carotene content in palm oil.