Protech Biosystems Journal

The Effect of Pennisetum Purpureum Fiber Addition On The Tensile Strength and Morphology Of Polyester Composite

2026-04-13T03:56:00+00:00

This study analyze the effect of fiber volume fraction variation of elephant grass fibers on the tensile strength properties of polyester resin matrix composites. The research was conducted in five stages: fiber extraction, alkaline treatment using a 1% NaOH solution, composite fabrication with polyester resin at a ratio of 2% of resin volume, SEM analysis, and tensile strength testing. The highest tensile strength (21,934 MPa) was obtained at a fiber-resin ratio of 10/90. Variation of fiber 5/95, tensile strength of (21.737 Mpa), modulus of elasticity of (1776.9 MPa) and elongation of (2.1788 mm), shows the dominance of the resin matrix in supporting loads. Fiber variation of 20/80, decrease in tensile strength to (21.169 MPa) and elongation of (2.2255 mm) due to uneven resin distribution. The most significant decrease occurred in the 30/70 fiber variation, the total tensile strength was (18.833 Mpa), the modulus of elasticity was (1390.3 MPa), although the elongation increased to (2.606 mm). Increased elongation indicates weak interface bonds due to fiber agglomeration and increased void, making the composite more susceptible to deformation before breaking. The SEM results support the tensile test results, where the 10/90 variation, shows the most homogeneous structure with good fiber distribution and minimal void count. Overall, the composition of fiber and 10/90 resin is concluded to be the most optimal composition because it provides the best balance between tensile strength, rigidity, and deformation ability of the material.

Characteristics Of Coconut Husk Briquettes Using Tapioca And Rice Flour Binders At Various Concentrations

2026-06-01T00:50:53+00:00

This study aimed to evaluate the effects of binder type and concentration on the quality of coconut husk charcoal briquettes and to assess the potential of rice flour as an alternative binder to tapioca flour. A two factorial Completely Randomized Design (CRD) with three replications was employed. The first factor was binder type (tapioca flour and rice flour), while the second factor was binder concentration (10%, 15%, and 20%). The quality parameters evaluated were moisture content, ash content, and calorific value. Data were analyzed using two-way Analysis of Variance (ANOVA) followed by Duncan’s Multiple Range Test (DMRT) at a 5% significance level. The results showed that binder type and concentration significantly affected the quality characteristics of the briquettes (p < 0.05). Moisture content and ash content increased with increasing binder concentration, whereas calorific value decreased. Moisture content ranged from 6.6% to 7.7%, while ash content ranged from 6.5% to 7.9%. The highest calorific value was obtained from briquettes produced with 10% tapioca flour binder (5405 cal/g), whereas the lowest value was observed in briquettes produced with 20% rice flour binder (4780 cal/g).. All treatments met the moisture and ash content requirements of SNI 01-6235-2000, while only briquettes containing 10–15% binder satisfied the minimum calorific value standard. Overall, 10% tapioca flour binder produced the best briquette quality, although rice flour showed potential as an alternative binder at appropriate concentrations.

Kapok-Based Agricultural Biomass Inhibitor for Steel Corrosion Control in H₂SO₄: Kinetic and Thermodynamic Study

2026-06-01T00:48:36+00:00

Steel corrosion in acidic environments is a critical issue affecting material durability and service life. This study aims to analyze the effect of kapok peel extract inhibitor concentration on the corrosion rate of steel in sulfuric acid media and to determine kinetic and thermodynamic parameters using Arrhenius plots and transition state theory. The weight loss method was employed with inhibitor concentrations (blank, 1000, 2000, and 3000 ppm) and temperatures (27, 35, and 45°C). Results indicate that corrosion rate significantly decreases with increasing inhibitor concentration, achieving a maximum inhibition efficiency of 74.06% at 3000 ppm and 27°C. Conversely, higher temperatures increase the corrosion rate. Kinetic analysis shows linear relationships in ln(CR) vs 1/T and ln(CR/T) vs 1/T plots. Activation energy increased from 15.82 to 26.75 kJ/mol, while ΔH° increased and ΔS° was negative. These findings suggest an adsorption-controlled inhibition mechanism forming a protective layer on the steel surface, indicating that kapok peel extract is a promising eco-friendly corrosion inhibitor.

Utilization of Water Hyacinth Biomass As a Reinforcement For Sustainable Polymer Composites: A Critical Review of Potential, Challenges, and Development Directions

2026-06-01T00:45:59+00:00

Water hyacinth (Eichhornia crassipes) is an invasive aquatic weed that often disrupts irrigation channels, water quality, and agricultural water resource management, but also has the potential to be a source of lignocellulosic biomass for the development of sustainable materials. This article presents a critical review of the utilization of water hyacinth fiber as a reinforcement for polymer-based composites by evaluating fiber characteristics, composite mechanical performance, technical challenges, and development opportunities. The results of the study indicate that despite water hyacinth fiber's low density, abundant availability, and relatively low cost, the improvement in the resulting composite's mechanical properties is still inconsistent due to weak fiber-matrix interfacial bonding, high porosity, and variability in fiber properties influenced by biological conditions and extraction methods. This review confirms that water hyacinth is more prospective for non-structural and semi-structural applications than as a primary structural reinforcement. In addition, fiber surface treatment, hybrid composite development, and filler integration are identified as key strategies to improve material performance. From a biosystems and agricultural engineering perspective, the use of water hyacinth as a composite raw material offers a promising approach in the management of aquatic weed biomass, the implementation of a circular economy, and the development of environmentally friendly materials with added value for the agricultural sector and sustainable management of biological resources.

The Effect of Npk Fertilizer Dosage on The Growth and Yield of Long Beans (Vigna Sinensis L.)

2026-06-07T05:29:09+00:00

Long beans (Vigna sinensis L.) are a horticultural crop with high nutritional and economic value. Long bean production can be increased through proper fertilization, particularly the use of NPK fertilizer containing the macronutrients nitrogen (N), phosphorus (P), and potassium (K). This study aims to determine the effect of various NPK fertilizer rates on the growth and yield of long beans. This study used a one-factor randomized block design (RBD) with four NPK fertilizer rates, namely 50 kg/ha, 100 kg/ha, 150 kg/ha, and 200 kg/ha, with three replications. The observed variables included the number of leaves, number of pods, pod length, and fresh pod weight. The data were analyzed using analysis of variance (ANOVA) at a significance level of 5%. The results of the study showed that the application of various NPK fertilizer doses had no significant effect on all growth parameters and yields of long beans. However, the 150 kg/ha dose tended to produce the highest number of pods (15.0 pods) and the longest pod length (73.4 cm), while the 200 kg/ha dose produced the highest fresh pod weight (418.3 g). The absence of a significant effect of the treatments is likely due to the high rainfall during the study, which caused nutrient leaching and reduced fertilizer effectiveness.

Physic, Chemical, Mechanic and Thermal Characterization of Cellulose Fiber From Balinese Pandan as Polymer Composites Reinfocement

2026-06-04T06:58:50+00:00

Natural fibers as reinforcements for biocomposites continue to be investigated from various sources that are beneficial to both humans and the environment. This study aims to investigate the characteristics of Cordyline australis fibers, or Balinese pandan fibers (CAf)—which are sustainable and eco-friendly—following treatment with a NaOH solution for use as reinforcements in polymer composites. Bali pandan leaves were soaked for 7–10 days until decomposition occurred and then combed with a steel comb to remove the fiber pulp. The Bali pandan fibers (CAf) were then soaked in a 5% (wt/v) NaOH solution for 2 hours and thoroughly washed until the pH reached neutral. The characteristics of raw CAf and 5% (wt/v) NaOH-treated CAf include physical, mechanical, chemical, and thermal properties. The findings of the investigation show that the tensile strength of CAf increased from 436.15 ± 35.5 MPa to 848.15 ± 57.46 MPa after treatment with 5% (wt/v) NaOH. The surface roughness of CAf reached 2.35 µm following treatment with 5% NaOH (wt/v) due to the dissolution of amorphous compounds and erosion of the wax layer. The thermal stability of CAf reached 700 °C with a char decomposition rate of 28.29%. These findings offer a new and renewable fiber option for use as a composite reinforcement.

Crop Production Prediction Model Using Fuzzy Associative Memory Based on Agroclimatic and Land Characteristic Variables

2026-06-16T16:54:54+00:00

Crop production prediction is important to support agricultural planning, resource allocation, and early decision-making in farming systems. Crop yield is influenced by various factors, including land characteristics and agroclimatic conditions. This study aims to develop a crop production prediction model based on agroclimatic and land variables using the Fuzzy Associative Memory (FAM) method. The study used secondary data from a crop production dataset containing land area, average air temperature, rainfall, and production variables. The modelling stages included determining input and output variables, constructing fuzzy sets, defining triangular membership functions, developing FAM rules, forming F AM matrices, performing model examination, and conducting defuzzification using the winner-takes-all approach. The input variables consisted of land area, air temperature, and rainfall, while the output variable was crop production classified into small, medium, and large categories. The results show that FAM can map linguistic input conditions into production categories through structured fuzzy rules. This model can be used as an initial approach for crop production prediction, especially when dealing with limited data and uncertain agroclimatic conditions.

Thermal Resistance And Morphological Characterization of Pennisetum Purpureum Fibers Treated With Naoh as A Composite Reinforcement Candidate

2026-06-16T17:21:10+00:00

Natural fibers are widely developed as composite reinforcing materials because they are environmentally friendly, lightweight, and have good mechanical potential. One of the natural fibers that has the potential to be used is elephant grass fiber (Pennisetum purpureum) because it has a high cellulose content and abundant availability. However, the content of lignin and hemicellulose on the surface of the fibers can affect the characteristics of the fibers so that alkaline treatment is required. This study aims to analyze the effect of variations in sodium hydroxide (NaOH) concentrations on the thermal characteristics, morphology, and chemical structure of elephant grass fibers. The research method used was an experimental method with 0%, 1%, and 3% NaOH treatment for 2 hours. Characterization was carried out using Thermogravimetric Analysis (TGA), Scanning Electron Microscope (SEM), and Fourier Transform Infrared Spectroscopy (FTIR). The results showed that alkaline treatment affects the thermal degradation pattern of fibers due to reduced hemicellulose and lignin. SEM observations showed that the fiber surface became rougher and cleaner after NaOH treatment, while FTIR results showed a change in function groups that indicated a reduction in non-cellulose components. The 3% NaOH treatment produced the most significant morphological changes, but began to show indications of damage to the fiber structure. Based on the results of the study, the alkaline treatment of NaOH affects the characteristics of elephant grass fibers so that it has the potential to be used as an environmentally friendly composite reinforcement material.

Implementation of Yolov8 For Digital Image-Based Classification of Mangosteen Fruit Ripeness Stages

2026-06-16T17:05:59+00:00

Manual determination of mangosteen (Garcinia mangostana) ripeness still relies on human visual observation, which may lead to subjective and inconsistent assessments. This study aimed to develop a YOLOv8-based model for detecting mangosteen ripeness stages. The research adopted the Cross Industry Standard Process for Data Mining (CRISP-DM) framework, which includes business understanding, data understanding, data preparation, modeling, evaluation, and deployment stages. The dataset consisted of 600 mangosteen images classified into six ripeness stages, namely Stage 1 to Stage 6, with 100 images in each class. Image annotation was performed using bounding boxes, and the dataset was divided into training, validation, and testing subsets using a 70:20:10 ratio. Five YOLOv8 variants, namely YOLOv8n, YOLOv8s, YOLOv8m, YOLOv8l, and YOLOv8xl, were trained and compared based on precision, recall, mAP50, and mAP50-95. The results showed that YOLOv8m achieved the best performance, with a precision of 0.772, recall of 0.941, mAP50 of 0.933, and mAP50-95 of 0.919. YOLOv8m was selected as the best model because it obtained the highest mAP and recall values, indicating its ability to detect mangosteen ripeness stages more effectively. These findings demonstrate that YOLOv8 has the potential to be used as a supporting system for automatic mangosteen sorting based on ripeness stage.

A Effect of Elephant Grass Fiber Volume Fraction on the Tensile Strength and Morphology of Agricultural Biomass-Based Epoxy Matrix Composites

2026-06-16T17:18:42+00:00

This study investigates the effect of elephant grass fiber (Pennisetum purpureum) volume fraction (5%, 10%, 20%, and 30%) on the mechanical and morphological properties of epoxy matrix composites. While conventionally limited to livestock feed, this research explores the fiber's potential as a sustainable engineering reinforcement. The composites were fabricated using the hand lay-up method after treating the fibers with a 5% NaOH solution for 2 hours. Tensile testing was performed according to ASTM D3039, and morphological analysis was conducted using Scanning Electron Microscopy (SEM). The results showed that increasing the fiber volume fraction improved tensile strength and elastic modulus up to an optimum value at 20% fiber content, reaching 13.02 N/mm² and 772.90 MPa, respectively. Conversely, elongation decreased with higher fiber content. SEM analysis revealed that the 30% fiber fraction led to decreased mechanical properties due to voids, fiber pull-out, and uneven fiber distribution. This study concludes that the 20% volume fraction provides the optimum mechanical performance, offering great potential for agricultural engineering applications, such as lightweight structural components and post-harvest machinery panels.

The Effect Of Starter Concentration Variation (Rhizopus oligosporus) On The Quality of Virgin Coconut Oil

2026-06-25T06:10:06+00:00

Coconut is an agricultural commodity with significant development potential, as it can be processed into various high-value products, one of which is Virgin Coconut Oil (VCO). VCO can be produced through a fermentation method by adding tempeh yeast (Rhizopus oligosporus), which plays a role in breaking down the coconut milk emulsion, thereby facilitating the oil separation process. This study aimed to determine the effect of varying concentrations of tempeh yeast on the quality of Virgin Coconut Oil (VCO) produced through the fermentation method. The research was conducted using an experimental method with a Completely Randomized Design (CRD) consisting of one factor, namely variations in tempeh yeast concentration at 0.2%, 1.1%, and 2%, with a fermentation time of 36 hours. The quality parameters analyzed included yield, color, aroma, taste, moisture content, and free fatty acid (FFA) content. The data obtained were statistically analyzed to determine the effect of treatments on VCO quality. The results showed that variations in tempeh yeast concentration had a significant effect on the aroma and yield of VCO, but did not significantly affect color and taste. The highest yield was obtained at the 2% tempeh yeast treatment, reaching 26.8%. The concentration of tempeh yeast also affected the moisture content of VCO, with the lowest moisture content observed at the 2% treatment. All treatments met the requirements of the Indonesian National Standard (SNI 7381:2022), with a maximum moisture content limit of 0.2%. The free fatty acid (FFA) content tended to increase with higher tempeh yeast concentrations, with the lowest value obtained at the 0.2% treatment (0.066%). All treatments remained within the acceptable limits of SNI 7381:2022. Based on these results, the 2% tempeh yeast treatment was determined to be the best treatment, as it produced the highest yield and lowest moisture content while maintaining chemical quality in accordance with the established standard.

Effect Of Variation In Coconut Shell Activated Carbon On The Characteristics Of Household-Scale Filtration Water

2026-06-25T06:06:58+00:00

Water is a fundamental requirement for human liFe; therefore, water intended for consumption must be clean and meet established quality standards. In Indonesia, clean water quality standards are regulated under the Regulation of the Minister of Health of the Republic of Indonesia Number 2 of 2023, which defines the criteria for water to be considered saFe and suitable for drinking. To obtain water that meets these standards, an efFective filtration process is required. In this study, activated carbon derived from coconut shell waste was utilized as the filtration medium. The preparation of activated carbon was conducted in two stages: carbonization through controlled combustion to produce charcoal, followed by chemical activation using a 15% sodium hydroxide (NaOH) solution for 24 hours at room temperature. This research aimed to characterize the performance of a portable water filtration device using difFerent masses of activated carbon. The experimental design employed three replications for each activated carbon variation. The evaluated parameters included pH, total dissolved solids (TDS), taste, odor, iron (Fe), fluoride, and nitrate concentrations. The results demonstrated that the optimal performance was achieved with 1000 grams of activated carbon, producing a pH value of 7.4, TDS of 297 mg/L, taste score of 4, and odor score of 4, with other measured parameters meeting the applicable quality standards. Activated carbon addition at varying dosages effectively removed metallic (Fe) and non-metallic (nitrate and fluoride) contaminants, reducing their concentrations to below detectable limits in all treatments and producing filtered water that complied with drinking water quality standards.These findings indicate that the portable water filtration device incorporating 1000 grams of activated carbon provides optimal treatment performance and shows significant potential for community application in supplying drinking water that complies with the Regulation of the Minister of Health of the Republic of Indonesia Number 2 of 2023.