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Gorontalo Province possesses significant mineral resource potential, particularly gold, silver, and copper, positioning the mining sector as a key driver of regional economic growth. However, a shortage of skilled local labor and the scarcity of vocational educational institutions in the mining field severely hamper human resource development in this sector. This study aims to design a Mining Polytechnic Campus in Gorontalo by applying sustainable architecture principles, encompassing energy efficiency, environmentally friendly materials, sound wastewater management, and user comfort. The research approach involves literature studies, field observations, interviews with relevant stakeholders, and quantitative data analysis regarding resource potential, the number of senior high school students, and educational space requirements. The design results emphasize site arrangement, building mass configuration, utility systems, and interior and exterior spaces that support academic, social, and community activities. The application of sustainable architecture principles is expected to create a campus that not only meets the needs of mining vocational education but also contributes to environmental conservation and sustainable regional development.

The increasingly complex global energy problem drives the need for efficient, low-cost, and environmentally friendly energy storage systems. This study aims to analyze the power performance of two symmetric supercapacitor prototypes using Nitrogen-doped Graphene-Like Carbon (N-GLC) as the electrode material and 1 M  as the electrolyte, with different electrode substrates: aluminum and copper. Both prototypes were tested through charging and discharging processes using resistive loads of 470 ohms and 560 ohms for 5 minutes. The analyzed parameters include voltage, current, power, and output energy. The results show that the aluminum electrode achieved a higher maximum charging power of up to 18 mW; however, its energy discharge efficiency was very low at only 0.87%. In contrast, the copper electrode demonstrated a more balanced charging and discharging performance with an energy discharge efficiency of 19.4%. Analysis also indicates that the copper substrate maintains better voltage stability after 6 hours of storage compared to aluminum, which experienced significant degradation. Thus, the copper electrode is superior in maintaining the power and stability of a simple N-GLC-based symmetric supercapacitor system.

Ballast water plays a crucial role in maintaining ship stability during shipping, but it also carries environmental and human health risks due to the heavy metals it carries. This study aims to examine the health risks posed by exposure to heavy metals in ballast water and to assess the effectiveness of management practices implemented in the maritime industry. Using a literature review method, this study examines various scientific sources related to the content of heavy metals such as lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) in ballast water, as well as their impacts on human health and marine ecosystems. The results indicate that heavy metals in ballast water can cause long-term toxic effects such as neurological disorders, kidney damage, and respiratory and reproductive disorders. The greatest risk is experienced by maritime workers who are directly exposed through inhalation or skin contact during the ballast water sampling and processing process. To minimize these risks, strict work safety protocols, improved ballast water treatment technology, and regular monitoring of heavy metal levels are required. Thus, this study emphasizes the importance of strengthening ballast water management policies and practices that are oriented towards human health and environmental sustainability.  

With growing antimicrobial resistance becoming a major health concern, there is an urgent need to explore alternative treatment options. This study examined the efficacy of copper sulfate pentahydrate (CSP) against eight microorganisms commonly implicated in vaginal infections. We tested three Candida species (C. albicans, C. glabrata, and C. tropicalis) along with five bacterial species, including Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Gardnerella vaginalis, and Pseudomonas aeruginosa. The agar dilution test was performed at concentrations ranging from 0.0001M to 0.7M of CSP. We obtained an effect of CSP antimicrobial, which was concentration-dependent. Concentrations low ( ≤ 0.007M) did not influence growth significantly. We observed partial growth inhibition at medium concentrations (0.05-0.07M, equivalent to approximately 780 -1092 µg/ml) of the solution. The growth of bacteria and yeasts was fully inhibited at 0.05M and 0.07M, respectively. The dose required to kill the organisms (not merely inhibit their growth) was 0.25M (approximately 2014 µg/ml) across all microorganisms used, and we verified this by observing no growth when samples were inoculated into fresh media. These findings have indicated that CSP possesses good antimicrobial efficacy against typical vaginal pathogens at doses that may be applied in topical therapies. However, some additional research is required, especially the research that will investigate the toxicity on human cells and the production of suitable formulations to be used clinically.

As a manufacturing company engaged in the processing of copper and wire products, PT Tembaga Mulia Semanan, Tbk requires human resources with optimal performance to support the achievement of organizational goals. This study aims to examine the effect of work motivation and work environment on employee performance at PT Tembaga Mulia Semanan, Tbk. This research employed a quantitative approach with data collection conducted through questionnaire distribution. The research population consisted of all employees of the South Continuous Rod (SCR) Division, totaling 65 employees, with a sample of 42 respondents. The collected data were analyzed using multiple linear regression analysis with the assistance of SPSS software. The results of the t-test indicate that work motivation partially has a positive and significant effect on employee performance, as shown by a t-value of 4.265 which is greater than the t-table value of 2.022, with a significance level of 0.000 < 0.05. The work environment also partially has a positive and significant effect on employee performance, indicated by a t-value of 6.080 which is greater than the t-table value of 2.022 and a significance value of 0.000 < 0.05. Furthermore, the F-test results show that work motivation and work environment simultaneously have a positive and significant effect on employee performance. The coefficient of determination (R²) of 63.52% indicates that variations in employee performance can be explained by work motivation and work environment, while the remaining percentage is influenced by other factors outside this study.

This in-depth study explores the comprehensive marketing strategies implemented by CV. Logam Jaya Gallery, a leading copper and brass craft business entity in Tumang Village, Boyolali. The research aims to identify the key factors behind the company's resilience in the face of intense industry competition. Using a qualitative approach, operational data was obtained in depth. The results show that the company integrates direct marketing through national and international exhibitions, while optimizing digital channels and e-commerce for broader global market penetration. Despite its success, CV. Logam Jaya Gallery faces significant obstacles such as market demand fluctuations, limitations in manual production technology, and competitive pressures. As a mitigation measure, the company diversifies its products and adopts contemporary technology to efficiently increase its operational capacity. Strategic synergies with the government and the private sector were also strengthened to expand promotional access. This success was also supported by fundamental pillars in the form of cultural heritage and intergenerational craftsmanship. Through a combination of organized management, sustainable design innovation, and adaptation to market dynamics, the company has succeeded in establishing itself as a competitive creative industry player on the national and global stage.

This in-depth study explores the comprehensive marketing strategies implemented by CV. Logam Jaya Gallery, a leading copper and brass craft business entity in Tumang Village, Boyolali. The research aims to identify the key factors behind the company's resilience in the face of intense industry competition. Using a qualitative approach, operational data was obtained in depth. The results show that the company integrates direct marketing through national and international exhibitions, while optimizing digital channels and e-commerce for broader global market penetration. Despite its success, CV. Logam Jaya Gallery faces significant obstacles such as market demand fluctuations, limitations in manual production technology, and competitive pressures. As a mitigation measure, the company diversifies its products and adopts contemporary technology to efficiently increase its operational capacity. Strategic synergies with the government and the private sector were also strengthened to expand promotional access. This success was also supported by fundamental pillars in the form of cultural heritage and intergenerational craftsmanship. Through a combination of organized management, sustainable design innovation, and adaptation to market dynamics, the company has succeeded in establishing itself as a competitive creative industry player on the national and global stage.

Asset management and equipment maintenance are crucial aspects in supporting smooth business operations, particularly in the copper crafts industry. Merapi Karya Cipta, located in Dusun III, Tumang, Cepogo District, Boyolali Regency, owns various production equipment assets that play a direct role in the work process, yet their management remains rudimentary and unplanned. This community service activity aims to increase copper craftsmen's understanding and awareness of the importance of asset management and equipment maintenance to improve operational efficiency. Qualitative methods were used through observation, interviews, and direct outreach to the craftsmen. The results of the activity demonstrated increased knowledge and a shift in participants' perspectives on business management, particularly regarding equipment maintenance and division of labor. The craftsmen began to understand that routine maintenance can be performed simply and does not always require significant costs. Therefore, this activity is expected to help maintain the continuity of the production process, reduce the risk of equipment damage, and support increased productivity and the well-being of the local community.

This study examines the impact of industrial activities in Bontang City, a major center for natural gas processing and fertilizer production, which potentially increases heavy metal contamination in coastal waters. Specifically, the research focuses on the accumulation of lead (Pb) and copper (Cu) in Anadara granosa, a benthic bivalve selected as a bioindicator due to its capacity to accumulate pollutants. The study aims to analyze Pb and Cu concentrations in Anadara granosa tissues collected from the waters of Selangan Hamlet, Bontang City, as an indicator of local environmental quality. The research was conducted over a six-month period, involving shellfish and water sampling from four observation stations. Heavy metal analysis was performed using Atomic Absorption Spectrophotometry, and the results were evaluated against relevant environmental quality standards, including Government Regulation of the Republic of Indonesia Number 22 of 2021. The findings revealed the presence of Pb and Cu at all sampling stations, with varying concentrations. The highest Pb and Cu levels were recorded at the South Station, while the lowest concentrations were observed at the East and North Stations. Overall, the measured concentrations of both metals significantly exceeded established safety limits, indicating serious risks to aquatic ecosystems and human health. These results confirm Anadara granosa as an effective bioindicator of heavy metal pollution and highlight the urgent need for further studies and mitigation efforts.

The decline in the performance of the die casting machine in 1998 after a long period of producing copper terminals showed dimensional defects and instability in product quality, especially in nozzle clogging, reduced copper flow, crust buildup on the gooseneck, plunger movement obstruction, and hydraulic pressure leaks. The purpose of planning the replacement and repair of die-casting machine components is to obtain replacement and repair costs, replacement and repair schedules for the period 2026, and the ratio of maintenance costs to profits. The replacement and repair planning method includes collecting previous maintenance data, applying the inspection-replace-repair-overhaul (IRRO) method, evaluating component conditions, predicting component service life, predicting labor costs, predicting supporting equipment to be used in maintenance, predicting the time to replace spare parts or reinstall repaired components, estimating replacement and repair costs for the period 2026, and calculating the ratio of replacement and repair costs to profits. The planning results obtained replacement and repair costs for the 2026 period are 75.770.000,- IDR with an estimated die casting machine rental rate of  1,500,000 IDR/hour which has the potential to be rented for 1,200 hours/year, and the ratio of maintenance costs to profits is 10,02 % which implies that the die casting machine with a capacity of 40 units/hour is still suitable for use and has the prospect of generating profits for the next few years.

This research focuses on the synthesis and characterization of the double salt copper(II) ammonium sulfate hexahydrate, Cu(NH4)2(SO4)2·6H2O. The study aims to obtain the compound in crystalline form and evaluate its properties through yield calculation, solubility testing, and Fourier Transform Infrared (FTIR) spectroscopy. The synthesis involved reacting copper(II) sulfate pentahydrate (CuSO4·5H2O) with ammonium sulfate ((NH4)2SO4) under controlled conditions, followed by crystallization. The process produced 10.84 grams of crystalline Cu(NH4)2(SO4)2·6H2O with an 86.23% yield, indicating efficient synthesis. Solubility tests showed that the crystals were polar, soluble in polar solvents like water and hydrochloric acid (HCl), partially soluble in ammonium hydroxide (NH4OH), and insoluble in less polar solvents like ethanol and chloroform (CHCl3). FTIR analysis confirmed the presence of functional groups such as O–H, N–H, and S–O stretching vibrations, supporting the proposed molecular structure. The findings demonstrate that Cu(NH4)2(SO4)2·6H2O can be efficiently synthesized, and its physicochemical properties align with theoretical expectations. This study contributes to the understanding of double salt synthesis and characterization, relevant for inorganic chemistry, material science, and potential applications in catalysis and coordination chemistry.

Trace elements such as copper, zinc, selenium, and chromium play essential roles in various enzymatic reactions, antioxidant defense mechanisms, and overall metabolic regulation, making them crucial for maternal and fetal health. During pregnancy, the demand for these micronutrients increases significantly due to physiological changes and the needs of the developing fetus. Inadequate or excessive levels of these trace elements can lead to altered fetal development and may impact neonatal outcomes immediately after birth. Given the sensitive developmental window of gestation, the intrauterine environment—including micronutrient status—has been hypothesized to influence neonatal physiological parameters such as heart rate, respiratory rate, and Apgar scores, which are commonly used to assess neonatal wellbeing in the early minutes of life. This study attempts to explore the impact of maternal trace element status—specifically copper, zinc, selenium, and chromium—along with selected maternal parameters (BMI, parity, gravida) on indicators of neonatal wellbeing, including heart rate, respiratory rate, and 5-minute Apgar score. A cross-sectional study was conducted in the Delivery Room of the Obstetric Hospital in Al-Diwaniya City, Iraq, involving 50 mother-infant pairs. Data collection occurred from December 1, 2024, to February 10, 2025. Maternal blood samples were analyzed using atomic absorption spectrophotometry to determine serum concentrations of copper, zinc, selenium, and chromium. Neonatal outcomes were assessed via standard clinical evaluations: heart rate and respiratory rate were measured immediately postpartum, and Apgar scores were recorded at five minutes. Statistical analyses included Pearson correlation and multiple linear regression to assess associations between maternal factors and neonatal outcomes. Bivariate and multivariate analyses indicated limited but noteworthy associations. Maternal serum chromium levels were significantly associated with increased neonatal respiratory rate (p = 0.026), suggesting a possible stimulatory or stress-related effect.

UD. Indokarya Brass is a company engaged in the brass handicraft industry with its main products being door handles and bells. The main raw materials used in the production process include brass, copper, tin, and aluminum, which are obtained from suppliers both within and outside the city. On average, raw materials are received weekly with quantities of 50–100 kg of brass, 7–10 kg of copper, 10–15 kg of tin, and 3–5 kg of aluminum. In addition, the company also uses additional materials in the form of thinner and epoxy purchased from nearby hardware stores with less frequent purchases, namely 5–10 liters of thinner every month and around 5 kg of epoxy every two months. To date, the company has not had a structured policy for procurement and control of raw material inventory. This condition results in excess inventory of several types of raw materials which actually incurs high costs, both in terms of storage costs and warehouse maintenance costs. This excess inventory ultimately has an impact on reduced efficiency and decreased company profits. This study was conducted to analyze the existing inventory system and compare the company's current policy with a proposed method for more optimal inventory control. The calculation results show that the proposed method is able to provide significant inventory cost savings, namely 83.25% in brass raw materials, 15.28% in copper, 14.6% in tin, 43.37% in aluminum, 4.66% in epoxy, 4.2% in thinner, and 40.7% in other raw materials. Thus, the implementation of the right inventory control method can improve operational efficiency and help companies reduce cost burdens, so that profits can be more optimal.

In response to increasing competition in the manufacturing sector, PT X—a copper busbar manufacturing company—implemented Lean Manufacturing supported by Value Stream Mapping (VSM) to improve production efficiency and reduce supply chain costs. This study utilizes VSM, Value Stream Analysis Tools (VALSAT), and Root Cause Analysis (5 Whys) to identify sources of waste and formulate improvement strategies. The analysis identified three dominant wastes: waiting time, product defects, and excess inventory. These were mainly caused by the lack of standardized material procedures, inadequate supporting equipment, and poor integration between the incoming inspection process and the Enterprise Resource Planning (ERP) system. To address these issues, the study proposes installing silica rolls, providing air wipers and flatness tools, developing standardized work instructions, and integrating Internet of Things (IoT) technology with the ERP system for real-time monitoring. As a result of implementing these solutions, PT X successfully reduced its defect rate from 6.23% to 1.32%, decreased lead time, and achieved notable savings in supply chain costs. The findings demonstrate that integrating Lean Manufacturing principles with VSM can effectively eliminate non-value-added activities, streamline production processes, and enhance overall competitiveness. This study reinforces the strategic value of Lean tools in continuous improvement initiatives within the manufacturing industry.

Adding too many electrical components to a vehicle can cause a lack of electrical energy. To overcome this, the capacity of the charging system needs to be improved. One method is by changing the diameter and number of turns of the copper wire in the stator coil. This study tested various combinations of wire diameter and turns to examine their effects on the voltage and temperature produced by the stator coil. The test used wire diameters of 0.7 mm, 0.9 mm, and 1.1 mm, with 50, 60, and 70 turns, at a constant engine speed of 3000 RPM for 5 minutes. The lowest voltage was recorded with a 0.7 mm diameter and 50 turns 26.5 V at the start and 25.7 V at the end. The highest voltage came from the 1.1 mm diameter with 70 turns 51 V at the start and 48.6 V at the end. The starting temperature for all variations was 36 °C. The lowest end temperature was 47.3 °C (0.7 mm, 50 turns), and the highest was 48.8 °C (1.1 mm, 70 turns). The results show that increasing both diameter and the number of turns raises voltage output, while temperature also increases slightly.

Using a descriptive method with a triangulation approach including observation, document analysis, and interviews this study ensures data reliability. Daily monitoring is conducted on wastewater flow and pH levels, while monthly laboratory analysis covers eight key parameters: Total Suspended Solids (TSS), iron (Fe), copper (Cu), zinc (Zn), total chromium (Cr), phosphate (PO³), oil and grease, and pH to evaluate the perfomance of the treatment system. The treatment process begins with the inflow of 960 m³ of wastewater per day into the storage pond, where aeration is applied to ensure homogenization before being transferred to the neutralization unit. pH adjustment is carried out by adding NaOH or HCl before the wastewater undergoes coagulation and flocculation stages. The study’s findings indicate that the WWTP meets the environmental quality standards established in accordance with the Decree of the Head of the Investment Coordinating Board of the Republic of Indonesia (2020), Number SK.214/1/KLHK/2020 concerning the Permit for Wastewater Disposal into the Sea on Behalf of PT Pembangkit Jawa Bali Unit Pembangkitan Gresik. This study emphasizes the importance of systematic monitoring and treatment in wastewater management.

Afghanistan, often called a "geological treasure trove," is richly endowed with vast mineral deposits worth over $3 trillion. The minerals, including copper, lithium, iron, gold, and rare earths, can be used to resurrect the nation's economy, reduce dependence on foreign aid, and bring about political stability. However, three decades of conflict, political turmoil, corruption, and inadequate infrastructure have been a hindrance to the effective exploitation of the resources. This paper examines the role of mining in Afghanistan's economic and political development, distilling the opportunities and challenges in the industry. Drawing on comparative case studies from resource-rich countries like Botswana and Chile, the study highlights the importance of open government, robust regulatory institutions, and strategic foreign partnerships. The evidence suggests that an efficiently operated mining sector would be a driver of sustainable development, provided that Afghanistan addresses deep-seated systemic evils in the form of corruption, insecurity, and environmental degradation. The research concludes with policy imperatives aimed at maximizing the contribution of the sector to national development.

In the curcumin compound there are aromatic compounds that have electronic spins on each side of the benzene. In previous research, the concentration of curcumin and H2O as coatings on copper coils could provide physical changes to the characteristics of copper coils, namely increasing the strength of the magnetic field and increasing the electric current in the coil. The fuzzification process can be described using membership variables with concentrations of curcumin and H2O as input, magnetic field strength and current as output. It is known that the greatest concentration of curcumin indicates increased magnetic field strength and electric current. Simulation of the aromatic spin on the curcumin compound as an Op Amp shows that the highest curcumin concentration value results in an increase in the output voltage (Vout).                                                                                                

The increase in human activities, such as industrialization, urbanization, and transportation, has led to air pollution, including heavy metal contamination such as lead (Pb). Lead originates from vehicle emissions, industrial activities, and fossil fuel combustion, which have detrimental effects on the environment and human health. One effective method for monitoring air pollution is biomonitoring using bioindicators, such as lichen. Lichen is sensitive to air quality and can absorb pollutants, including heavy metals, through its surface. This study uses a literature review to analyze the role of lichen as a bioindicator of heavy metal pollution, specifically lead. Several lichen species, such as *Xanthoparmelia xanthofarinosa* and *Canoparmelia aptata*, are known to accumulate heavy metals from the environment. The results show that the lead content in lichen varies depending on the pollution level in the location. Areas with high traffic have higher lead concentrations compared to areas with low traffic. The advantages of using lichen as a bioindicator include low cost, practicality, and its ability to provide long-term data on air quality. With this understanding, lichen data can be used for pollution mitigation and evidence-based policies to reduce the impact of air pollution. Further research is recommended to explore the potential of lichen in detecting other heavy metals, such as cadmium (Cd) and copper (Cu).  

Sustainable water resource management in Indonesian villages is essential to address poor water quality and low public awareness. This program aims to enhance the knowledge and skills of the community regarding sustainable water resource management. The methods used include training and water quality testing across 14 parameters, such as lead, copper, iron, chromium, pH, and free chlorine, in accordance with the standards set by the Ministry of Health Regulation. Results showed a 40% increase in community understanding after training, with all tested water parameters found to be within safe limits. The program successfully engaged the community in water quality monitoring, raising awareness and encouraging participation in sustainable water resource management. Although some participants initially faced difficulties in using the testing tools, intensive guidance was provided to overcome these challenges. In conclusion, the program positively contributed to improving the community's knowledge, skills, and participation in maintaining better water quality in the village.