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Processing plastic waste into fuel oil with pyrolysis technology. Research on plastic oil as an alternative fuel has been widely conducted. One of them is research on processing plastic bag waste into fuel oil with pyrolysis technology. In this study, a set of pyrolysis equipment was made by Lecturers and Students of UMNU Kebumen. The plastic waste used in this study was 1 kg of plastic bag. Meanwhile, the pyrolysis process used a temperature of 250oC-300oC. The fuel oil produced in the pyrolysis process of this study was approximately 400 ml. The average density of fuel oil from plastic bag waste was 0.733 gr/ml. The results of this density calculation are in the possibility of the density of gasoline, namely 0.710 gr/ml to 0.770 gr/ml. This pyrolysis process shows great potential for converting plastic waste into an environmentally friendly alternative energy source. Furthermore, the efficiency of this pyrolysis technology can be improved by adjusting the temperature and processing time, as well as by selecting a wider variety of plastic types. This technology has the potential to be applied more widely in plastic waste management within the community as a solution to reduce environmental pollution while generating renewable energy.

This study aims to describe the implementation of ecobrick activities as an environmentally friendly initiative and as a strategy to enhance fine motor development in early childhood aged 4-6 years in Jatirejo Village, Pasuruan Regency. This research employed a descriptive qualitative approach using observation, interviews, documentation, and hands-on ecobrick practice. The findings indicate that the ecobrick process-which includes collecting plastic waste, washing, drying, cutting, inserting plastic pieces into bottles, and compressing the contents-effectively improves children’s fine motor skills, particularly in hand-eye coordination, finger strength, accuracy, and cutting ability. Children demonstrated positive responses, including high enthusiasm, curiosity, and increased awareness of environmental preservation. The activity also strengthened children’s social development through cooperation, communication, and shared responsibility. Overall, ecobrick activities function not only as an innovative waste-management solution but also as an educational medium that holistically supports child development and instills environmental awareness from an early age.

Waste from used Polypropylene (PP) and High Impact Polystyrene (HIPS) plastic is problematic in its management. The purpose of this research is to obtain the fatigue life of a mixture of used PP and HIPS plastics in its pure plastic. The research method is through the stages of mixing pure PP and 50% volume of used PP, pure HIPS and 50% volume of used HIPS, injection molding of R.R. Moore standard fatigue test specimens for pure PP, pure HIPS, pure PP + used PP, and pure HIPS + used HIPS, checking the straightness and smoothness of the molded specimen surface, fatigue testing with increasing serial loads, analysis of the bending stress curve (S) against fatigue life (N). The results showed that mixing used PP and used HIPS in pure plastic affected the fatigue life at the test speed (n)=2100 rpm for recycled PP was 9.84% shorter than pure PP, and at n=1600 rpm for recycled PP it was 9.32% shorter than pure PP, while at n=2100 rpm for recycled HIPS it was 4.45% shorter than pure HIPS, and at n=1600 rpm for recycled HIPS is 4.77% shorter than pure HIPS, while the fatigue life of pure PP is 1627704 cycles and the fatigue life of pure HIPS is 1291636 cycles or the fatigue life of pure HIPS is 20.65% shorter than pure PP, the implication of which is that the addition of used PP and used HIPS reduces the fatigue life to 9.84% for PP and 4.45% for HIPS.

Fore Coffee's #FOREsponsible campaign prioritizes the principle of environmental conservation. They collaborate specifically with a company called Robries, which processes plastic waste into valuable products such as furniture and home decor. This study aims to determine how much influence the #FOREsponsible public relations campaign message has on Fore Coffee's brand image. The theory used is the Campaign Message theory (variable X) in accordance with Venus's research (2019), with indicators including Message Content, Message Structure, and Message Frame. Brand image (variable Y) is measured based on the dimensions of strength, favorability, and uniqueness in accordance with Keller's theory (2013). This study uses a quantitative approach with a survey method, namely by distributing questionnaires to 94 samples selected using the Slovin formula, probability sampling techniques, and simple random sampling methods. The collected data were then analyzed using simple linear regression techniques. The results of the analysis show the influence of variable X (Campaign Message) on variable Y (Brand Image). From the results of simple linear regression, the R Square value (coefficient of determination) was obtained at 63.3%, which means that approximately 63.3% of the influence on Fore Coffee's brand image comes from the #FOREsponsible campaign message on Instagram. While the remaining 37.7% is influenced by other factors not covered in this study. This proves that the campaign message has a significant influence on Fore Coffee's brand image.

Partial Denture (GTSL) is an ideal option for patients with missing teeth, with various materials such as thermoplastic nylon (flexible denture), acrylic resin, and metal. Heat-cured acrylic resin and thermoplastic nylon are the two most commonly used materials for denture bases. Denture bases must have sufficient mechanical strength to withstand chewing forces. Acrylic resin, made from polymethyl methacrylate, has become the gold standard in prosthodontics due to its affordability, ease of fabrication, and satisfactory functional results. However, acrylic resin tends to be rigid, brittle, and may cause soft tissue irritation. As an alternative, thermoplastic nylon offers high physical strength, resistance to heat and chemicals, as well as plastic and flexible properties. However, thermoplastic nylon tends to absorb water, change color, and is difficult to repair. Thermoplastic nylon-based dentures provide comfort, aesthetics, and good marginal adaptation, with less soft tissue irritation compared to acrylic resin dentures. Although both materials have comparable characteristics in terms of retention, stability, and durability, flexible dentures are more attractive to patients who prioritize comfort and aesthetics.

Plastic waste detection in indoor environments is an essential challenge in the development of intelligent cleaning systems and robotic automation. Small and medium-sized plastic debris is often difficult to identify using conventional methods due to variations in color, shape, and reflectance. This study proposes an image-processing-based approach that combines thresholding and contour detection techniques to improve the accuracy of detecting plastic objects on floor surfaces. The initial stage involves converting the image into a color space that is more stable under varying illumination, such as HSV or grayscale, to reduce the influence of lighting intensity. Subsequently, adaptive thresholding is applied to separate plastic objects from the background by using dynamic threshold values tailored to the image’s conditions. The segmentation results are refined through morphological operations such as opening and closing, enabling the removal of small noise and enhancing the clarity of object boundaries. The core stage of the system employs contour detection to extract object shapes and areas, allowing the identification of plastic waste based on size, perimeter, and specific geometric characteristics. Experiments were conducted under different lighting conditions and various floor types, and the results demonstrate that the proposed approach successfully detects plastic debris with satisfactory accuracy and relatively fast processing time. Therefore, this method is suitable for implementation in robotic cleaning systems, indoor cleanliness monitoring devices, and other computer vision applications requiring real-time and efficient object detection.

Beton sebagai material utama konstruksi sering mengalami panas hidrasi yang menyebabkan perbedaan suhu permukaan dengan suhu inti, akan berpotensi retak dini dan penurunan kuat tekan. Penelitian ini menganalisis potensi air es dan fly ash 10% substitusi semen untuk memperkecil suhu beton mutu 35 MPa dengan aditif tipe D (retarder) dan F (superplasticizer), serta pengaruhnya terhadap kuat tekan. Metode deskriptif menggunakan data sekunder mix design tiga variasi: non fly ash, fly ash 10% dan fly ash 10%+air es 10°C. Suhu beton segar diukur dengan thermogun/thermometer lalu kuat tekan uji silinder diameter 150x300 mm umur 7 hari dan 28 hari dengan total 18 benda uji. Hasil menunjukkan suhu beton segar non fly ash berada pada rentang normal, beton fly ash 10% turun 1-2°C (reaksi pozzolanik lambat yang mengurangi panas hidrasi dari C2S, C3S, dan C3A), beton fly ash 10% + air es turun 5-6°C. Kuat tekan 7 hari menunjukkan beton non fly ash 33,69 MPa, beton fly ash 10% 34,14 MPa, beton fly ash 10%+air es 34,73 MPa. Pada umur 28 hari menunjukkan beton non fly ash 39,73 MPa, beton fly ash 10% 39,80 MPa, dan beton fly ash 10%+air es 39,65 MPa – semua melebihi mutu rencana.

The issue of inorganic waste such as plastic and used paper in industrial environments remains an important issue that affects the cleanliness and aesthetics of work areas. PT Pertamina Patra Niaga Fuel Terminal Rewulu faces challenges in managing non-hazardous solid waste due to limited sorting systems and waste transportation frequency. This Community Service activity aims to improve workers' understanding and skills through socialization and training in making ecobricks as a solution for utilizing inorganic waste. The methods used include pre-activity stages, socialization and hands-on practice, and evaluation through pre-tests and post-tests. The results of the activity showed a significant increase in participants' knowledge after the training, proving the effectiveness of interactive methods in strengthening understanding of the 3R (Reduce, Reuse, Recycle) concept. In addition to reducing waste volume, this activity also fostered awareness and participation among workers in creating a clean and sustainable work environment. The results of this community service are important as a first step in building a culture of independent waste management in industrial environments and can be replicated in other locations with a similar approach. Keywords: Implementation of Pancasila values, bullying prevention, character education, primary school, SDN 1 Jatisela, school environment, student behaviour.

Beton merupakan material utama konstruksi yang masih memiliki kelemahan pada kuat tekan dan permeabilitas. Inovasi dengan penambahan Superplasticizer diharapkan mampu meningkatkan kualitas beton. Permasalahan penelitian ini adalah bagaimana pengaruh variasi dosis Superplasticizer (1%, 1,5%, dan 2% dari berat semen) terhadap kuat tekan dan permeabilitas beton dibandingkan beton normal. Penelitian ini menggunakan metode eksperimen dengan membuat 48 sampel beton silinder dan kubus yang diuji kuat tekan pada umur 7, 14, dan 28 hari serta permeabilitas pada umur 28 hari. Hasil penelitian menunjukkan bahwa penambahan Superplasticizer mampu meningkatkan kuat tekan dan menurunkan permeabilitas, sehingga dapat menghasilkan beton yang lebih kuat, kedap air, dan tahan lama.

This research proposes an alternative model for predicting the plasticity potential of clay soils, updating the previous model developed by Firincioglu and H. Bilsel. The alternative lies in the use of the fine fraction content (FC) as the predictive variable, replacing the percentage of sand fraction content (SC) previously suggested. The analysis was conducted on 61 low-plasticity clay (CL) soil samples, classified using the Casagrande and Moreno-Maroto systems, by examining the relationship between consistency limits (LL, PI), grain fractions (sand, silt, clay), and related parameters (FC, sand-silt-clay spectrum, and sand fraction ratio). The correlation analysis results show significant findings, including a strong positive correlation between sand content and the sand ratio (SR), as well as a negative correlation between sand content and FC, and between FC and SR. The performance of the substitute Casagrande quadratic model [2] reveals the best predictive accuracy among the proposed models ( [1], R² =0.90; [3], R²  0.89; [4], R² =0.43; [5], R² =0.93; [6], R² =0.93; [7], R² =0.89; [8], R² =0.89), with the highest R2 value of 0.93, MSE of ≈4.01, and MAE of ≈1.44–1.47. The equation is .

This research seeks to define polycyclic aromatic compounds, which are chemical compounds consisting of fused aromatic rings that do not contain heteroatoms or substituents. Many of these compounds are known to be carcinogenic and are primarily produced through the incomplete combustion of carbon-containing fuels such as wood, coal, diesel, grease, and tobacco. Pure polycyclic aromatic compounds generally appear as colorless, white, or pale green solids that often develop a yellowish tint over time. These substances are commonly found in coal tar, crude oil, creosote, and tar deposits in industrial and urban environments. Despite their widespread occurrence and potential health risks, only a limited number of polycyclic aromatic compounds are utilized in industrial applications, including the manufacture of medicines, dyes, plastics, and pesticides. Furthermore, this research examines the distribution, persistence, and accumulation of these compounds in the environment, as well as their toxicological effects on human health, ecosystems, and long-term environmental sustainability.

The global environmental crisis caused by plastic pollution has intensified in recent years, particularly in aquatic ecosystems such as rivers, lakes, and oceans, creating an urgent need for effective and sustainable solutions. This article explores the potential role of aquatic bacteria in degrading plastic polymers by reviewing the biological and molecular mechanisms these microorganisms use to break down complex synthetic materials. Special attention is given to key genes and enzymes involved in plastic degradation, including PETase and MHETase, which play a critical role in the decomposition of polyethylene terephthalate (PET). In addition, the article highlights advanced gene expression and analysis techniques, such as metagenomics, transcriptomics, and proteomics, to better understand bacterial activity and degradation dynamics in natural environments. The main problem addressed is the continuous and unsustainable production and consumption of plastics, which has resulted in extensive pollution of freshwater and marine systems, while conventional waste treatment methods remain largely ineffective. The objective of this article is to provide a comprehensive scientific review of biotechnological approaches used to analyze and utilize aquatic bacteria for plastic degradation, focusing on molecular aspects and environmental applications. Using a literature review method, studies published between 2018 and 2024 were analyzed to evaluate effective bacterial models, technological challenges, and future prospects. The findings indicate that aquatic bacteria offer promising potential as biological tools for mitigating plastic pollution through sustainable environmental strategies.

Waste management remains one of the major challenges in urban areas, including Rungkut Menanggal Subdistrict, Surabaya. Although two active waste banks already exist, community participation and the optimization of social and material assets remain limited. This community empowerment program aims to optimize local potential through the strengthening of social and material assets based on waste bank activities using the Asset-Based Community Development (ABCD) approach. This approach emphasizes the utilization of existing community strengths and resources to create sustainable social transformation. The program was carried out through five participatory stages: discover, dream, design, define, and destiny. The results show a significant improvement in the community’s capacity for household waste management. Residents were able to process approximately 100 kg of organic waste into compost and create creative products such as decorative bags made from plastic waste. Moreover, collaboration among local institutions such as Karang Taruna Arkidli, PKK, Posga Venus, Posga Bumi, and KSH increased, strengthening collective action in environmental management. This program demonstrates that the ABCD approach effectively enhances social capital, increases community participation, and generates both economic and environmental benefits. Waste bank management based on local asset empowerment can serve as a model for inclusive and adaptive community development in urban environmental contexts.

Café retrorika is one of the cafes located in Batu City, Malang, which adopts a green marketing concept with a unique aesthetic touch, combining the concepts of “Retro” and “Eco-friendly”, where almost all of the café’s furniture and decorations are made from recycled materials, such as old windows, used motorcycle tanks, gas cylinders and rims, which are transformed into high-art decorative elements. Awareness of the importance of sustainable business is growing, including in the culinary sector. Cafes and restaurants now compete not only in terms of taste and service but also in their commitment to environmentally friendly concepts. Moreover, today’s consumers are increasingly selective in choosing places to eat that support local products, use environmentally friendly materials, and strive to reduce plastic waste. This is one of the reasons for building cafes with different concepts, as done by the owner and founder of Retrorika café. This study uses a qualitative approach with a case study research type. Data collection techniques include participant observation, interviews and documentation. The result show that Retrorika café was built based on the personal idealism of its owner as a green movement activist, rather than market calculations. The café’s “Retro” identity serves as physical evidence of sustainability practice through the use of used furniture while also creating a nostalgic experience. Its marketing strategy focuses on education through the Re-dukaci program, Retrorika goes to Halokes and Sa-Si-Su as an effort to prove the authenticity of green practices and mitigate greenwashing. These results can be concluded that the founder’s passion shapes the Green Corporate Identity and becomes a source of sustainable competitive advantage that is difficult to imitate.

Fasting as a spiritual and health practice has been practiced for thousands of years in various religious and cultural traditions around the world. In the last decade, researchers have shown increasing interest in the health aspects of fasting, not only from a physiological but also a psychological perspective. This phenomenon is interesting to study further, especially in the context of modern society which often faces stress, anxiety, and various mental disorders. The approach used in this study was a qualitative approach with a literature study method that analyzed in depth various reference sources related to the mental impact of fasting. The results of the review of several studies show that fasting has been proven to have an effect on mental health because it has a significant impact on overall mood improvements, with reduced anxiety levels and increased feelings of calm. Furthermore, another important aspect of mental health is cognitive function, which includes attention, concentration, memory, and executive function. It was found that cognitive alertness is generally maintained during short- to medium-term fasting, but begins to decline after longer fasting durations. Fasting also has an impact on extraordinary psychological resilience and good mental health despite advanced age. Researchers attribute this extraordinary mental resilience to the consistent practice of long-term fasting, which may have induced significant neuroplastic and psychological adaptations.

Indonesia is one of the countries with abundant availability of palm fiber composite, yet its application in advanced material technology remains limited. On the other hand, most motorcycle helmets available in the market are made from ABS plastic, which has limitations in impact energy absorption and may increase the risk of head injuries during accidents. This study aims to develop helmet composites based on palm fiber and epoxy resin by varying the fiber volume fractions (15%, 25%, and 35%) and alkali soaking durations (75, 150, 225, and 300 minutes). The impact strength test results showed that the combination of 35% fiber volume and 225-minute alkali soaking produced the highest specific impact energy (SIP) of 0.142 J/mm². As a comparison, SNI-compliant helmets made from ABS plastic only reached an EPS value of 0.00972 J/mm², indicating that palm fiber-based composite helmets could improve impact energy absorption efficiency by more than 14 times. The results conclude that increasing the fiber volume fraction and optimizing the alkali treatment duration significantly enhances the impact resistance, making ijuk-based composite helmets a promising alternative for safer and more eco-friendly protective gear.

Many used ABS plastic wastes have problems in their management. The aim of this research is to obtain a prediction of the fatigue life of a mixture of ABS plastic and used ABS as an injection molding product. The research method is carried out through the stages of mixing used ABS with a volume of 10%, 20%, and 30% in ABS grade A and grade B; making fatigue test specimen molds according to R. R. Moore standards, injection molding of a mixture of used ABS and ABS grade A and grade B, checking the straightness and smoothness of the specimen surface, fatigue testing with increasing serial loads, analysis and making a graph of bending stress (S) against fatigue life (N) (S-N Curve). The results of the study showed that the addition of used ABS had an effect on the fatigue life of both grade A and grade B of ABS, where the fatigue life of grade A of ABS increased with the addition of the volume percentage from 0% -30% of used ABS with the highest value at the addition of 30%, namely 43698.9 cycles, while in grade B of ABS, the fatigue life decreased with the increase in volume from 0% -30% with the highest fatigue life in grade B of ABS plastic without a mixture or 0%, namely 41377.5 cycles, the implication of which is that the addition of 0% -30% of used ABS in grade A can increase the fatigue life, but grade B of ABS actually decreases its fatigue life.

The demand for lightweight materials with high mechanical strength has driven the development of aluminum alloys, particularly Al-Mg-Si, through deformation processes such as cold rolling. This study aims to analyze the effect of varying degrees of cold rolling deformation on the grain aspect ratio and macrohardness of homogenized Al-Mg-Si alloys. Deformation was applied at three thickness reduction levels—5%, 10%, and 20%—followed by microstructural characterization using optical microscopy and macrohardness testing in accordance with ASTM E-18 standards. The results show that increasing deformation levels lead to elongated grain morphology, with the grain aspect ratio rising from 1.16 to 2.07 and macrohardness increasing from 46.64 HRE to 62 HRE. The emergence of slip lines and grain flattening indicates the occurrence of intense plastic deformation, while work hardening results from dislocation accumulation that impedes further slip motion. These findings confirm a strong correlation between microstructural evolution and mechanical property enhancement in cold-deformed Al-Mg-Si alloys. This research contributes to the optimization of cold rolling parameters to produce engineering materials with a desirable balance of strength, formability, and fatigue resistance for applications in the mining and heavy manufacturing industries.

This study aims to investigate the impact of packaging type and storage temperature on the physical, chemical, and sensory properties of chili blocks during storage. Additionally, the study aims to identify the optimal packaging and storage temperature combination, as well as to characterize the quality attributes of chili blocks. The experimental design employed was a Completely Randomized Design (CRD) in a factorial arrangement with two factors: packaging type and storage temperature. In this study, using aluminum foil as primary packaging, PP plastic packaging, and paper as secondary packaging, and 3 treatment storage temperatures, each repeated as many as 3 trials, so that it has 18 experimental units. Data analysis using ANOVA with Duncan's Multiple Range Test (DMRT)at a significant level of 5% using the SPSS18 program. The results showed that secondary packaging types and storage temperatures did not significantly affect physical properties (moisture content) and organoleptic properties (color, aroma, texture), but significantly affected the chemical properties (pH, vitamin C, ash content) and secondary packaging types the good for chili block is alufo + plastic packaging and refrigerator storage temperature (10oC), and good chili block characteristics are: Refrigerator storage (temperature 10oC) with alufo + plastic packaging: lowest physical properties (moisture content) 27.29, chemical properties (lowest pH 5.23, Vitamin C 12.91 and ash content 6.35).

This study comprehensively examines the concept of Sharia law by highlighting the main divisions within Islamic law: taklifi law and wadh'I law. Taklifi law encompasses five normative categories: obligation, recommendation, permissibility, makruh, and prohibition, which serve to regulate individual behavior in accordance with Sharia principles. Meanwhile, wadh'iy law emphasizes the causes, conditions, and requirements for the validity of a legal act, thus forming a normative framework that guarantees the validity of an action from an Islamic legal perspective. This study uses a normative approach through a literature review of primary sources of Islamic law, such as the Qur'an, Hadith, and classical and contemporary fiqh literature. The results of the study indicate that the division between taklifi and wadh'iy law is crucial for understanding the structure and complexity of Sharia law, both in terms of the vertical relationship between humans and God and the horizontal relationships between individuals. This study also examines the contemporary issue of plastic surgery from an Islamic legal perspective.  Plastic surgery is permissible for medical purposes, such as reconstruction following an accident, congenital defect, or impaired bodily function, as it aligns with the principles of preserving benefit and eliminating harm. However, plastic surgery solely for aesthetic purposes is considered forbidden, as it constitutes altering God's creation without a sharia (Islamic) justification. This finding confirms that the division of sharia law is not merely theoretical but also relevant in addressing modern issues, including in medical practice, and has important implications for the development of contemporary Islamic law and its application within the national legal context.