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High strength concrete is currently a very important part in construction, namely construction that has very high strength. The strength of concrete depends on the material used and its size. The size of the concrete constituent materials affects the porosity of the resulting concrete because porosity affects the strength of the concrete. For this reason, efforts are made to use concrete constituent materials that can reduce porosity in concrete. Various materials can be used as additives to give concrete high strength. Among these materials are fly ash and silica fume. Fly ash is a product of coal combustion and functions as a substitute for pozzolanic materials in cement as much as 0, 5, 7.5, 10, 12.5, 15, and 17.5% because it has a very fine grain size < 350 mesh and silica fume ash, which functions as a substitute for fine aggregate 0, 10, 15, 20, 25, 30, and 35% which comes from the ashes of burning refined palm shells with a size < 350 mesh. Materials were prepared, namely: cement, fine aggregate, coarse aggregate, fly ash, silica fume, and weighing water. All the ingredients were stirred until homogeneous and put into a cube-shaped mold measuring 150 x 150 x 150 mm while compaction was carried out using an iron stick, then the mold was left for 24 hours, removed from the mold then soaked in water and soaked in water for 28 days. The compressive strength test and characterization of XRF and XRD and SEM were carried out. Based on the research as outlined in the graph, the maximum compressive strength of substitution of 12.5% fly ash into cement is 45.20 MPa, while the substitution of silica smoke from boiler slag into fine aggregate has a maximum compressive strength of 25% of 50.84 MPa. The results of the XRF characterization of high strength concrete showed that the dominant compounds were 54.60% CaO, and 32.50% SiO2, followed by other compounds. The results of the XRD test showed that the phases formed were calcite (Ca), quartz (SiO2), and anorthite (CaAl2Si2O8) and the distribution of C-S-H was fairly even in the concrete. Thus, fly ash and burning ash of palm shells can affect the compressive strength of concrete for the better, namely the strength increases higher than normal concrete. [ABSTRACT FROM AUTHOR]

Variation of fly ash and pulp paper composition at 110°C for 6 hours was carried out to discern the effect of fly ash and pulp paper addition in papercrete. sixth variations in paper pulp and fly ash composition were employed to perceive the characteristic that occurs in the sample. The papercrete material composition was weighed, mixed until it became homogeneous and then casted in a mold with a size of 18 x 5 x 2 cm3. Papercrete samples were allowed to stand within the mold at room temperature for 24 hours and released from the mold to stand again for the next 24 hours, after which it heated at 110°C for 6 hours. Characterization using XRF, SEM-EDX as well as Mechanical and physical tests carried out after the samples was cold. Papercrete with sample code K6 has the highest flexural strength and density value of 2.03 MPa and 2.4 gr/cm3 while papercrete with sample code K1 has the lowest flexural strength and porosity value of 0.4 MPa and 17.89%. Characterization shows that the chemical composition of the samples was dominated by the oxide compound CaO and SiO2 in papercrete. [ABSTRACT FROM AUTHOR]

The purpose of this research is to increase added value and maximize the potential for abundant availability of local basalt. The utilization of basalt needs to be a major concern in Indonesia. The additive effects on the crystallization and hardness of basalt glass-ceramics were studied. Eight specimens were modified by SiO2 (10 and 20 wt.%), MgO (5 and 8 wt.%), and CaO (7 and 10 wt.%). After melting at 1200℃ for 2h, it was quenched with pH 7 water at room temperature. The nucleation temperature was kept at 600℃ for 1hr and the crystallization temperature at 1050℃ for 3 h. According to the XRF results, the chemical composition of basalt glass-ceramics consist of 35-41.9 SiO2 + 12.21-25.9 Al2O3 + 9.6-16.4 Fe2O3 + 17.4-24.0 CaO+3.06-5.27 MgO by percent weight. In addition to the base crystal phase (anorthite, olivine, and pyroxene), diopside and cristobalite formed as the effect of the additive. The highest hardness of basalt glass-ceramics was 564 Hv0.1N, an increase of 50.4% compared with raw basalt. From the analysis of variance (ANOVA), the increase in hardness effect by SiO2 content had a 68% contribution and a P-value of 0.02. [ABSTRACT FROM AUTHOR]

Geopolymers have become one of the alternative materials for environmentally friendly concrete. Pozzolan materials with high alumina-silicate content such as fly ash and bottom ash (FABA), basalt, and clay are potential materials for geopolymer concrete synthesis. In Indonesia, the amount of FABA, basalt, and clay is very abundant. The purpose of this study was to determine the properties and character of geopolymer concrete with the composition to which additives were added. Geopolymers were activated using a mixture of NaOH and Na2SiO3. The mixture of activator and geopolymer material was cured at a temperature of 80°C for 12 hours. Concrete samples are formed in cubes for compressive strength tests and molded beams for flexural strength tests. Variations in the use of fibers in flexural strength test samples are applied to determine the effect of fibers on the deflection threshold of geopolymer concrete. The results of the cube concrete compressive strength test ranged from 0.04–0.47 MPa with the highest compressive strength at the C3 variation of 0.47 MPa. The flexural strength ranges from 0.11–2.15 MPa with the highest flexural strength at variation C3 of 2.15 MPa. The use of fibers can provide a better deflection threshold despite reducing the maximum flexural strength. The use of fibers needs to be regulated to obtain a good flexural strength with a proportional deflection threshold. [ABSTRACT FROM AUTHOR]

High water hardness levels will have several negative health effects, which can lead to blockage of blood vessels and problems with kidney disease. The people in the surrounding of java-sea faced clean water crisis caused by saltwater intrusion. In the preliminary study, the well water contained 890 mg/l of hardness, 4460 mg/l of Total Dissolved Solids (TDS), and 0.0709 mg/l of lead metal. The study aims to investigate the effect of the combination of activated carbon with various Iodine numbers and Coconut fiber on improving the quality of well water. The method used is filtration with three filters consisting of coconut fiber with depth of 10 cm and activated carbon with thickness of 60 also three various Iodine numbers are 650 mg/ g, 800 mg/g, and 1000 mg/g also operating times are 0, 15, 30 and 45 minutes. The filters have three kinds i.e. filter A contains Iodine of 650 mg/g, filter B consists of 800 mg/g, and filter C includes 1000 mg/g. It operates for 45 minutes with each sampling for 15 minutes. The parameters studied were hardness, TDS, and lead metal content. Filtration on the three filters has met the Regulation of the Minister of Health number 32 of 2017 with the highest filter efficiency on filter C. The decreasing efficiency of hardness is 60.78%, TDS is 89.90%, and Pb is 84.90%. Combining Iodine number of 1000 mg/g and coconut fiber with 15 minutes of operating time generates high performance to remove the chemical compound. [ABSTRACT FROM AUTHOR]

Stability on the slope can be disrupted due to the influence of nature, climate, and human activities, so it can cause landslides due to the imbalance of forces acting on the slope or the force in the slope area that is greater than the restraining force on the slope. Landslides are natural disasters that often occur in Indonesia. Landslide disaster is also one of the natural disasters that cause property losses and casualties and cause damage to transportation facilities and infrastructure. Slope loosening usually occurs during the rainy season due to an increase in pore water on the slope. One of the areas in Indonesia located at the foot of Mount Sumbing is one of the area's most vulnerable to landslides based on the Landslide Threat Map in Indonesia. The height of this area is located at 400 to 3200 Mdpl, in addition to having steep reliefs this region also has a high potential for landslide hazards. This research was carried out with observations to take slope measurements with theodolite measuring instruments supported by the help of google earth and ArcGIS for contour map/making and soil sampling in the field. Furthermore, soil testing is carried out based on soil parameter data and slope measurements that will be analyzed against Safety Factors (FK). Based on the existing analysis, the results of slope stability analysis of the six slopes reviewed showed FK>1 values for dry soil and wet soil. Meanwhile, the condition of saturated soil shows the number FK<1, with an unstable slope state [ABSTRACT FROM AUTHOR]

In this study, two kinds of catalysts called LaNiMo-NZ and LaNiZn-NZ catalysts were synthesized using natural zeolite from Lampung as support by the incipient wetness impregnation method. The characterization of catalysts were carried out by Brunaeur-Emmet-Teller (BET), X-ray Diffraction (XRD), and X-ray Fluorescence (XRF). The hydrocracking reactions were carried out in a batch reactor at the reaction temperature of 310 oC and hydrogen pressure of 20 bar. The liquid product was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The catalysts were applied for biofuel production from palm oil by hydrocracking reaction. The results showed that the highest product contained hydrocarbon in the range C10−C26 (4.51 area%) using LaNiMo-NZ catalyst with the most compounds of olefin and normal paraffin. The catalyst was potential for biofuel production by hydrocracking reaction. [ABSTRACT FROM AUTHOR]

A practical and rapid analytical method for determining macromineral cations (sodium, ammonium, potassium, magnesium, and calcium) compositions in nutmeg species (Myristica spp.) aqueous extracts of tropical fruits potentially for electrolyte supplement by ion chromatography is presented. All nutmeg species were collected from the tropical plantation nutmeg area in Ternate and Tidore, North Maluku. The determination method is reliable and based on direct conductometric detection with non-suppressed ion chromatography systems. The method performed 8.0 mM HNO3 containing 0.02 mM Na2 EDTA as the mixture eluent and Metrosep C4-150/4.0 as the separation column in all macromineral determinations. Macromineral cations were completely eluted on the separation column within 12 min. The limit of detection (LOD) at S/N=3 using standard samples was 0.036, 0.053, 0.068, 0.093, 0.062, and 0.086 ppm (mg/l) for lithium, sodium, ammonium, potassium, magnesium, and calcium, respectively. The relative standard deviations (RSD) were less than 3% for peak height, area, and retention time. The coefficient correlation with peak heights versus the concentration range is linear with R2≥0.999. Potassium cation was the highest macromineral composition in all examined nutmeg species, both in fruit flesh and seeds. The highest and lowest potassium concentrations were found in Myristica succedanea (2870.4 mg/Kg) and Myristica argentea (2090.1 mg/Kg). The highest concentration of total macromineral cations in studied samples was Myristica succedanea (3933.5 mg/Kg). [ABSTRACT FROM AUTHOR]

As disasters continue to occur, various efforts are made to deal with them. In this digital era, technology plays an essential role in disaster mitigation and management efforts. In addition, society is increasingly adapting to technology. This research aimed to 1) identify the technology of disaster mitigation from disaster management institutions in Indonesia and 2) analyze transformation disaster mitigation technology for GeoHazard disaster risk reduction. This study applies a literature study approach to explore disaster technology data in several disaster management agencies. Research objects from five non-departmental government institutions that manage disasters in Indonesia. Secondary data was collected from websites of disaster management agencies, journal articles, activity reports, and books related to technology and disasters. Data analysis was carried out by descriptive and comparative analysis. Each non-departmental agency that manages disaster data manages specific data that can support analysis, evaluation, and prediction of disasters in Indonesia. Disaster technology as a disaster mitigation effort is published to the wider community to reduce disaster risk. Technologies used for disaster mitigation in Indonesia include Web-MobileGIS and Data Sources (WebGIS) InaRisk, Tsunami Early Warning System (INATEWS) 4.0, Indonesia Tsunami Early Warning System (InaTEWS), Landslide Early Warning System (LEWS), MAGMA Indonesia, and Geospatial Technology (InaGeoportal). The transformation of disaster technology is continuously used for disaster risk reduction in Indonesia. [ABSTRACT FROM AUTHOR]

The addition of Lampung - Indonesia natural zeolite material as an added material for the manufacture of geopolymer concrete has been carried out. Geopolymer is made by heating at various temperatures of 50, 70, 110, and 130°C with holding times of 6, 9, and 12 hrs. Analysis of chemical composition using x-ray fluorescence while the crystal phase using x-ray diffraction. The mechanical properties to determine the compressive strength of geopolymer concrete. While the physical properties in terms of density. The test results obtained the highest compressive strength of 13.53 Mpa from 130°C with a holding time of 6 hrs. The density of geopolymer concrete is between 1.255 to 1.874 kg/mm3, which is influenced by the composition of the concrete forming material. Lampung natural zeolite with a dominant composition of 67.15% SiO2 and 13.19% Al2°3 is very suitable to be used as a substitute for cement in geopolymer concrete. The crystalline phases formed in all concrete are quartz and albite. While at temperature variations, there are other crystalline phases. These different crystalline phases are influenced by the K, Na, Al, and Si bonds formed. [ABSTRACT FROM AUTHOR]

Kinetic leaching on recovery of cobalt (Co) and lithium (Li) from spent lithium-ion battery (LIB) cathode using tannic acid-acetic acid as leaching agent was carried out to discern the leaching mechanism in terms of acid concentration and temperature. Three kinetic models, i.e. shrinking core model (SCM) chemical reaction and product layer diffusion and shrinking particle model (SPM) film diffusion was employed to perceive the possible mechanism of Co and Li dissolution. Fitting experimental data using the models revealed that increasing acetic acid concentration caused the dissolution mechanism to follow SCM product layer diffusion. This was probably due to the molar ratio of acetic acid to Co was not sufficient to control the passivation of the Co(OH)2 product layer. In the case of tannic acid, increasing concentration obeyed SPM film diffusion model. Due to excess concentration of tannic acid in the liquid phase, dissolution was more influenced by the reduction rate of Co by tannic acid on the solid-liquid interface rather than mass transfer through the boundary layer (insoluble layer). Dissolution of Co and Li at elevating temperature obeyed SCM product layer diffusion, indicating higher temperature encourages the reduction rate to produce Co(OH)2 passivation layer. Still, at the same time, increasing temperature boosted ion movement and encouraged the diffusion through product layer. Activation energy (Ea) calculation yielded 5.53 kJ/mol and 26.8 kJ/mol for Co at 30-60 °C and 60-80 °C, respectively, while Li was 21.51 kJ/mol. Relatively low Ea (< 40 kJ/mol) indicated the physical interaction was more prominent than chemical reaction control. The plot between rate constant and reactant concentration showed that the effect of tannic acid and acetic acid concentration was significant for Co dissolution rate (order 0.927 and 0.638 for tannic acid and acetic acid concentration). For Li, the reaction order was 0.451 for tannic acid and 0.021 for acetic acid concentration, implying less influence of reactant concentration on Li dissolution. Although Li dissolution was less affected by reactant conditions, the recovery of Li and Co was almost identical in each experiment, which suggested the Li dissolution was controlled by Co dissolution through product layer passivation. [ABSTRACT FROM AUTHOR]

The strain gauge contains a tool to measure deflection and strain. In this design, the 4 strain gauge sensors are utilized, calculated on an aluminum shaft with a Wheatstone Full Bridge series of bridges. Each strain gauge sensor presents a resistor value of 350. The design of this measurement system applies a strain gauge sensor, provided an INA125 amplifier, processed by Arduino to produce data that will be displayed directly on the LCD. The output data was generated on measurements using a full bridge strain gauge sensor, which is BIT (Binary Digit) data, converted into Volts and processed into strain. The loadings were varied (10, 15, 20, and 25 kg). Experimental strain data processing under 10 kg loading conditions obtained the strain of 0.002345 GPa, proportional to the magnitude of the load. At the highest loading of 25 kg, the strain was also obtained at 0.002345 GPa. From these data, our acquisition system design for stress-strain measurement on aluminum shafts could properly function. [ABSTRACT FROM AUTHOR]