Background: The community service program conducted by OLE Research Group focuses on processing plastic waste using optical fiber technology to create handicrafts with economic value. The program is carried out in Popongan Village, Karanganyar Regency, and consists of two implementation phases. Objective: This activity aims to educate the community on transforming plastic waste, particularly used water jugs, into ornamental flower crafts enhancing the value through bouquets creation and integration of fiber optic as illuminated ornaments. Method: The program was conducted in two main phases, including outreach and training on making flowers from plastic water, followed by advanced practical in bouquets arrangement and installation of a simple fiber optic system. Program’s success was evaluated using a pre-test and post-test method. Results: The evaluation showed significant improvement in participants performance. Skills in making flowers increased from 30% in 85%. Ability to assemble simple fiber optic-based circuits improved from 0% to 65%, while confidence in participating in group creative activities rose from 40% to 90%. Conclusion: The program effectively enhanced both technical and non-technical skills of participants and supported the transformation of plastic waste into marketable product. Continued mentoring is needed ensure product consistency and strengthen marketing strategies.

Synthesis conditions strongly influence the morphology and crystallite size of ZnO, yet the coupled effects of OH- supply dynamics, precursor ratio, and reaction time on ZnO growth remain insufficiently understood. In this work, ZnO nanostructures were synthesized hydrothermally using zinc acetate and hexamethylenetetramine (HMTA), with and without NH4OH addition, to elucidate the mechanism governing morphology evolution. XRD confirmed the formation of phase-pure hexagonal wurtzite ZnO for all samples, while Williamson-Hall analysis revealed variations in lattice strain associated with the synthesis conditions. The addition of NH4OH significantly increased the OH- concentration, resulting in higher supersaturation, enhanced nucleation density, and smaller, more uniform crystallite sizes. This effect promoted the transition from agglomerated granular particles to well-defined anisotropic nanorods and hierarchical nanoflowers. In contrast, ZnO synthesized without NH4OH exhibited predominant grain coarsening and agglomeration with prolonged reaction time. Particle size distribution analysis further confirmed that alkaline conditions improved particle size uniformity, while TEM, HRTEM, and SAED observations verified the high crystallinity and preferential growth of anisotropic ZnO nanostructures. A simple crystal growth kinetics analysis indicated that NH4OH nearly doubled the apparent crystal growth rate constant, demonstrating that OH- availability governs both nucleation and subsequent crystal growth. These findings establish a unified mechanistic framework linking OH- supply dynamics, supersaturation, nucleation density, crystallite growth, and morphology evolution, providing practical guidelines for the rational design of ZnO nanostructures for photocatalytic, sensing, and optoelectronic applications.

ZIF-11/TiO2 heterojunction composite was successfully synthesized via a simple dispersion-mixing method, yielding a highly efficient photocatalyst for dye degradation. The integration of ZIF-11 and TiO2 formed a hybrid structure that combined the porous framework characteristics of ZIF-11 with the photoactive, semiconducting properties of TiO2, effectively overcoming the intrinsic limitations of each material, such as their wide band gaps and high electron-hole recombination rates. Characterization results revealed that anatase-phase TiO2 particles were uniformly distributed on the ZIF-11 surface, forming a Z-scheme heterojunction system that promotes efficient charge separation under UV irradiation. Photocatalytic evaluation demonstrated that the Z11T8 composite achieved an impressive 99.92 % degradation efficiency of indigo carmine within 180 min, a significant improvement over pure ZIF-11, which exhibited only 26.01 % efficiency. These findings confirm the synergistic effect between the adsorptive capability of ZIF-11 and the photocatalytic activity of TiO2, which operate in complementary ways. This study highlights a MOF-semiconductor heterostructure engineering strategy as an effective route for developing high-performance photocatalysts for the sustainable treatment of organic pollutants.

The objective of this research is to investigate the effect of pyrolysis temperature variation on the selectivity of gasoline fraction from polypropylene (PP) plastic waste. The pyrolysis process was conducted using a semi-batch stainless steel reactor at three different temperatures: 350, 400, and 450°C, each with a constant residence time of 60 min. The liquid products were condensed and analyzed using Fourier transform infrared spectroscopy (FTIR) and gas chromatography–mass spectrometry (GC-MS). Results show that the highest oil yield was obtained at 400°C (85.72 wt

The management of organic waste using an anaerobic reactor offers the potential for renewable energy production and nutrient recovery. This study evaluates the performance of a 3,000 L fiberglass anaerobic reactor designed to treat a mixture of kitchen waste, cow manure, and water in a 1:1:1 ratio. The process was conducted under mesophilic conditions (30–38 °C) over a 40-day batch cycle. The reactor produced a total of 63.75 m³ of biogas with an average methane content of 59.3%, equivalent to 0.193 m³ CH₄/kg VS. Additionally, the system produces approximately 2,700 kg/month of liquid effluent and 900 kg/month of stabilized solids. These results demonstrate the efficiency of substrate bioconversion and the potential for utilizing residues as organic fertilizer. This study emphasizes the technical feasibility of using a community-scale fiberglass reactor for organic waste treatment with measurable performance parameters.

Abstract Bismuth-lead glasses incorporated with different concentrations of P2O5 have been synthesized. The composition of the glasses is 53Bi2O3-28PbO-(19-x)B2O3-xP2O5 (BPBP) (x = 0, 0.25, 0.5, 0.75, 1.0, 1.25, and 1.5 mol%). All glasses were melted at 900°C for 40 minutes and subsequently annealed at 275°C for 8 hours and then cooled to room temperature at a cooling rate of 1°C/minute. Density measurements were carried out at room temperature using a pycnometer. It was shown that the density increases with increasing P2O5 concentration, that is, from 7.42 g/cm3 to 8.20 g/cm3. From the glasses composition and density data, several important physical properties of glasses were derived, i.e., P3+ ions concentration (Np), polar radius (rp), inter-ionic distance (ri), field strength (F), and oxygen packing density (OPD). With increasing P2O5 concentration, the Np value increases from 0 to 22.73 x 1021 ions/cm3the rp decreases from 0.2461 to 0.0383 Å, and the ri decreases from 0.9408 to 0.1446 Å. It was also shown that the OPD decreased from 56.10 mol/L to 62.19 mol/L, indicating that increasing P2O5 concentration raises the portion of Bridging Oxygen (BO) in the glass matrix.

This study was conducted to determine the impact of leachate pollution from landfills on the quality of well water around them and to map the leachate distribution. A total of eight sample locations were taken for laboratory testing, of the eight samples one was taken at the leachate outlet and the others were taken from wells around the Landfill. Laboratory tests were conducted to analyze the parameters of Potential Hydrogen (Ph), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Mercury (Hg), Cadmium (Cd), Lead (Pb), and Iron (Fe). The results of the test show that the pH and mercury parameters do not exceed the quality standards, however, other parameters such as BOD, COD, TSS, CD, PB, and FE show values ​​that exceed the quality standards. The standard for drinking water quality is based on the World Health Organization (WHO) and the Regulation of the Minister of Health (PERMENKES) of the Republic of Indonesia No. 02 of 2023 and PP No. 22 of 2021. The data creates a pollution distribution map showing areas with significant contamination levels. This finding indicates a significant influence of activities at the landfill on the quality of the surrounding groundwater. This study highlights the importance of proper leachate management to prevent further pollution. And to provide education to the community, especially those who use wells for consumption purposes, to carry out treatment first before consuming.

The energy conversion efficiency of Dye-sensitized solar cells (DSSCs) is still considered low, which is a challenge, especially in the developing of cheaper counter electrodes. A thin film of reduced Graphene Oxide-Cobalt Molybdenum Sulfide (rGO/CoMoS) composite was synthesized using the solvothermal method and used as a counter electrode to replace platinum in DSSCs. The present study investigated the impact of different annealing temperatures on the performance of DSSC after depositing rGO/CoMoS layers onto an FTO glass substrate using the slip-casting method. The study found that the increasing temperature annealing could enhance structural alignment, minimized imperfections, and strengthened intermolecular connections all play a role in improving electronic characteristics and catalytic performance. The DSSC performance test was found the highest efficiency at 6.71 %. The improved performance can be attributed to the synergistic effect between rGO and CoMoS, which provides high surface area and catalytic activity for electrolyte reduction. This study shows that rGO/CoMoS composite has excellent potential as a cost-effective and efficient counter-electrode material for next-generation DSSCs.

Composite rGO/ZnO NRs (NRs = nanorods) have been a photoanode material in DSSC solar cells. In this study, ZnO NRs were synthesized using a hydrothermal method with the addition of hexamethyl tetraamine (HMTA). The synthesized ZnO NRs was then composited with graphene oxide (GO) synthesized by the modified hummers method. The performance of rGO/ZnO NR composite material with various compositions of ZnO: GO ratio (w/w) as a photoanode has been investigated. The results show that graphene oxide is capable of decreasing the ZnO band gap energy. The composite of rGO/ZnO NRs shows its performance as a photoanode material in DSSCs. The composite with ZnO:GO (w/w) ratio of 1:2 showed better performance than the other rGO/ZnO NRs composite.

Abstract Boro-tellurite glasses composed of 57B2O3– (4-y)Na2O-–15Bi2O3-20TeO2–3TiO2–1Tm2O3-yHo2O3 (y = 0, 0.5, 1.0, 1.5, 2.0, and 2.5 mol%) were succesfully synthesised and the change in their absorption spectra in wavelength range 300-1100 nm were studied. All glasses were fabricated at the same melting temperature 1000°C and subsequenlty qunched and annnealled in the same manner. It can be seen that glass dopped with only Tm3+ ions (y = 0) shows three absorption peaks, i.e., 471, 686, and 792 nm. As Ho3+ ions were added, there were additional six new peaks appear, i.e., peaks located around 417, 450, 485, 538, and 642 nm. The study reveals that different peaks show difference of sensitivity to the additional Ho3+ ions concentration with peaks around 450 nm shows the most sensitive.

Problem Statement and Purpose. Groundwater is an important resource for agriculture, drinking water, and ecosystems in Sragen Regency, Central Java, Indonesia. However, the area is significantly water-stressed due to recurrent droughts, pollution, and unsustainable extraction methods. The aim of this study is to monitor the changes of groundwater storages during 2003-2024 using Gravity Recovery and Climate Experiment (GRACE) satellite mission and Global Land Data Assimilation System (GLDAS) products into Google Earth Engine (GEE) to advance Sustainable Development Goal 6 (Clean Water and Sanitation) and SDG 13 (Climate Action). Data and Method. The study employs GRACE data to analyze Total Water Storage (TWS) and the hydrological components -Soil Moisture SM and Snow Water Equivalent SWE- that GLDAS provides as a supplement. Merging these datasets within GEE seeks to understand groundwater trends from seasonal to long-term. Result and Discussion. The study observed an average decrease in groundwater storage, with observed stresses during drier-than-usual periods in 2015-2016 and 2018-2020. Whereas, contrary to this long-term declining trend, the groundwater generally rises during wet seasons and falls again during dry seasons, demonstrating seasonality in storage. Furthermore, quantitative analysis revealed a net groundwater storage decline of approximately 15-20% during the 2003-2024 period, with critical depletion phases correlating with events (2015-2016) and prolonged droughts (2018-2020). The GRACE-GLDAS-GEE integration demonstrated high efficacy in detecting seasonal recharge cycles (+8-12 cm equivalent water height during monsoon months) versus dry-season depletion (-10-15 cm), providing unprecedented spatial-temporal resolution for this tropical agricultural region. This approach offers a scalable model for implementing SDG 6.4 (sustainable water withdrawals) through precision aquifer management in developing economies facing climate stress. The results should hasten the consideration of better water management approaches to stop further depletion of groundwater through methods such as managed aquifer recharge and maximizing irrigation efficiencies. This study provides a good example of using GRACE and GLDAS data adoption for regional groundwater monitoring, thus setting a solid basis for interventions aimed at alleviating water scarcity for Sragen Regency and beyond. This information will also serve as input in making decision-supporting management, aligning with SDG 6 targets for sustainable freshwater resource allocation and addressing challenges posed by climate variability and increasing anthropogenic pressures under SDG 13.

Five boro-tellurite glasses with chemical formula 55TeO 2 -(12-x)B 2 O 3 -32ZnO-(1+x)Na 2 O (TZBN), (x= 0; 1; 2; 3; 4; mole%) were successfully synthesized by conventional melt-quenching technique. The physical properties of the glass was studied to understand effect of partial substitution between B 2 O 3 and Na 2 O. The density was measured using pycnometer based on Archimedes law. The other physical properties can be obtained by assisted some mathematical equation. Refer to the measurement, the density was found decreased by 4.905 to 4.590 gr/cm 3 because the molecular weight difference between B 2 O 3 and Na 2 O. Meanwhile the molar volume increased by 25.05 to 27.11 cm 3 /mole due to higher atomic radii of Na rather than B which raise NBO inside the glass network. Meanwhile, OPD , V o , polaron radius, inter-ionic distance, packing density,and number of bond per unit volume consequently have been decreased. While the Field strength has increase due to stronger Na-O bonds. Reflects from the results the TZBN glasses could be used as active material for laser.

Demographic growth, urbanization, economic development, agriculture, and consumption per capita have increased the demand for water resources. The population density of Surakarta affects the city’s ability to fulfil its residents’ clean water requirements. As an urban region, Surakarta may be impacted by development activities that degrade the quality and quantity of groundwater. This growing demand should be balanced against effective management of water source regions. This research aims to investigate groundwater vulnerability in Surakarta City. We employed the DRASTIC and GOD methods and compared both results. These methods used the overlay and indexing approaches using GIS based on field data and secondary data such as drill, rainfall, and topographic data. The results of DRASTIC show three types of vulnerability: high (0.21%; 9.87 ha), moderate (94.22%; 4,355.98 ha), and low (5.56%; 257.25 ha), while GOD method results in high (7.03%; 324.96 ha), moderate (52.90%; 2,445.84 ha), low (38.69%; 1,788.81 ha), and negligible (1.37%; 63.49 ha). Based on both methods, we identified Banjarsari district as a location with high groundwater vulnerability. The correlation coefficient between the two methods is 0.511. This value shows that the correlation criteria are acceptable and comparable. This research can be used by local authorities and policymakers to manage groundwater resources. Play This Podcast Article

Increasing population growth has resulted in increased vehicle ownership and the need for parking facilities, including in basements. This study aimed to explore the efficacy of palm shell activated carbon panels in reducing CO, NO2, HC, Pb, and noise. The experiment was conducted in a 4 m x 3 m x 2.1 m room using three treatments: without installed activated carbon panels; with 1 cm x 20 cm x 20 cm activated carbon panels; and with 2 cm x 20 cm x 20 cm activated carbon panels. During the measurement, three motorcycles were turned on and kept in idle mode. The concentrations of CO, NO2, HC, ambient Pb, and noise were measured. The results showed that the activated carbon panels were able to reduce CO, NO2, Pb, HC, and noise. The highest performance was obtained for 2-cm thickness of activated carbon panels, with CO, NO2, HC, Pb, and noise decreasing to 824 µg/m3, 8.4 µg/m3, 4.4 µg/m3, 0.2 µg/m3, and 87.44 dB, respectively. Following the adsorption process, the carbon content and pore size of the activated carbon panels had changed from 68.32% to 90.95% and 0.17-3.652 µm to 0.34-5.56 µm respectively for testing with 2-cm thickness panels.

Peningkatan volume sampah yang disebabkan oleh pertumbuhan penduduk dan aktifitas ekonomi menjadi permasalahan bagi semua pihak mulai dari hal pelaksanaan di lapangan, tata kelola teknis hingga sudut pandang manajerial. Penelitian ini bertujuan untuk menghasilkan alat bantu untuk mengatasi salah satu permasalahan dalam pendukung pengambilan keputusan yang disebabkan oleh kurangnya alat bantu dalam mengolah data untuk memudahkan dalam mendapatkan pengetahuan. Data volume sampah dalam penelitian ini menggunakan data sampah kota surakarta tahun 2017 sampai dengan tahun 2023. Segmentasi pada data volume sampah tersebut bertujuan untuk mengenali pola sumber penghasil sampah terbesar, sedang dan kecil. Pengetahuan terhadap segmen tersebut dapat digunakan sebagai pendukung dalam pengambilan keputusan strategis pengelolaan sampah kota surakarta. Adanya alat bantu ini, diharapkan pengelolaan sampah dapat menjadi lebih efektif dan efisien, serta memberikan solusi jangka panjang yang berkelanjutan bagi kota surakarta dan generasi di masa mendatang.

The waste problem is a problem for all parties because the negative impacts caused by waste are very diverse. Increase in waste volume caused by community activities. Research related to waste management that utilizes information technology and data mining is currently still widely open. It is hoped that the use of this technology can support decision-making in sustainable development. As a complement to this research, it also reveals that the public's perception of waste management regarding waste volume is a negative perception, which shows that the more people know about information about waste management, it has an impact on reducing waste volume. On the other hand, the positive perception shows that there is less Information about waste management has an impact on increasing the volume of waste. Both the results of the data mining process and public perception are in agreement. It is hoped that this suitability can be used as support for decision-making regarding waste management to maintain the sustainability of abiotic, biotic and cultural factors

The impact of the increasing volume of waste in the Putri Cempo TPA causes the emergence of pollutants in the form of liquid, gas or solid. Gas is a dangerous pollutant because it can cause respiratory disease and even death. methane gas (CH4), sulfurdioxide (SO2), ammonia (NH3), and hydrogen sulfide (H2S), so that it can be the cause of respiratory (respiratory)-related diseases cardiovascular, and physiological changes such as pulmonary function and blood pressure. This study tries to identify pollutant gases that arise in the Putri Cempo TPA and the detection method uses ZnO-TiO2-GO Material which previously used an adsorbent solution. The use of this material has the advantages of being practical, safer and easier to recycle. The gas identification carried out includes SO2, O3, NO2, H2S and NH3 gases. ZnO-TiO2 and GO materials were varied into variation A, B, C ,D And E. The results showed that The results show that the composition of TiO2; ZnO Graphene C (45%; 45%, 10%) shows better results for detecting NO2 gas than the p-aminodimethylaniline working solution used for laboratory measurements. The results show that the composition of TiO2; ZnO Graphene E (60%; 30%, 10%) shows the composition's ability to detect 10 times more H2S gas than the p-aminodimethylaniline working solution but the ability to detect NH3 is lower than the p-aminodimethylaniline working solution. composition variations in TiO2; ZnO ; Graphene B (30%; 60%, 10%), and D (80%; 15%, 5%) can detect exposure to SO2 and O3 gases 6 times more than p-aminodimethylaniline solution. From various compositions, it shows that TiO2, ZnO, Graphene materials are more dominant than aminodimethylaniline solution except for the detection of NH3 pollutant. The results of the research recommendations need to be developed prototypes for the detection of the five pollutant gases without having to go through laboratory testing. The development of a prototype of the pollutant gas detection tool can speed up the measurement of gas pollutants. So that it is easier for analysts to measure gas pollutants. It is necessary to develop the effect of the concentration of adsorbed pollutant gas on the composition of materials with various conductivity of material compositions for further research