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Copolymerization of eugenol with EGDMA is a cationic addition polymerization reaction. The results of the copolymerization can increase the number of active sites on the polymer, namely the benzene ring and hydroxyl group, causing a higher molecular weight. This study aims to synthesize 8% Copoly-Eugenol Ethylene Glycol Dimethacrylate (Co-EEGDMA) as a carrier in the process of separating phenol pollutants using liquid membrane techniques. Co-EEGDMA synthesis was carried out through a copolymerization reaction between eugenol and 8% EGDMA using boron trifluoride diethyl ether (BF3O(C2H5)2) as a catalyst. The results of the synthesis of carrier were characterized using Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM), and Thermogravimetry-Differential Thermal Analysis (TG-DTA). The 8% Co-EEGDMA produced was a reddish-brown powder. The results of characterization with FT-IR showed the loss of allyl groups and vinyl groups at wave numbers 1636 cm-1 and 995.2 cm-1, this condition is a parameter of the success of the synthesis. The results of SEM characterization showed that the morphology of Co-EEGDMA 8% was lumpy, round, and the distribution was uneven. Characterization with TG-DTA was carried out at a temperature range of 50-900. At 300 °C the samples of Co-EEGDMA carrier were degraded while at 400 °C the samples of Co-EEGDMA carrier experienced mass stability. The results of characterization with TG-DTA showed that the carrier was capable of being used to transport phenol at high temperatures. [ABSTRACT FROM AUTHOR]

Determination of the heavy metal content of Pb, Cd, and Mn in vannamei shrimp (Litopenaeus vannamei) in the waters of Labuhan Maringgai, East Lampung Regency. This research was conducted to determine the heavy metal contamination in the waters of Labuhan Maringgai, East Lampung Regency. Vannamei shrimp (Litopenaeus vannamei) was an aquatic biota that has the highest role in the absorption of heavy metals and had still commonly found in the waters of Labuhan Maringgai, so it was chosen as a bioindicator of heavy metal pollution. Shrimp sampling had been done by purposive random sampling method. Heavy metal analysis was carried out using Atomic Absorption Spectrophotometer (AAS) with wet digestion method which was carried out during sample preparation using HNO3 68% and H2O2 30%. The results of the analysis of metal concentrations of Pb, Cd and Mn in the vannamei shrimp samples, showed that the levels of Pb, Cd, and Mn metals had exceeded the safe limits set by BPOM RI No.5 of 2018. [ABSTRACT FROM AUTHOR]

Lampung is one of the provinces in Indonesia with an area of 34,623.85 km2 and has 15 districts/cities. Air pollution in Lampung Province has shown a significant increase, causing a decrease in air quality and environmental carrying capacity. This is based on the Lampung Province Regional Regulation Number 20 of 2014 concerning air pollution control. One of the most common inorganic air pollutants is sulfur dioxide (SO2). This study aims to determine the concentration of ambient air quality Sulfur dioxide (SO2) in the dry and rainy seasons and to compare the air quality in 15 districts in Lampung Province from the results of measurements using the Passive sampler method. Sampling was carried out in the rainy season (January) and dry season (August). The mean concentration was used as the annual mean value, and then data analysis was performed using a two-way ANOVA. Based on the two-way ANOVA test, the researchers found that the concentration of SO2 was not significantly different (p-value >α) between the average concentration of SO2 in each district/city for two consecutive years. This indicates that there is no difference in the average SO2 between the dry season and the rainy season, in other words that the dry and rainy seasons have no effect on SO2 pollutant levels. [ABSTRACT FROM AUTHOR]

The increase in Covid-19 is increasingly significant, especially in Jakarta. The increase in Covid-19 cases in Jakarta today touched 849,843 new cases as of August 30, 2021. The high increase in Covid-19 cases is due to the presence of this new variant of the Covid-19 virus, namely the lambda variant which is more deadly than the previous Covid-19 virus. Based on the data on the increase in the Covid-19 virus, a website was created regarding hotels that have self-isolation facilities. The purpose of this website is to help people who need a place to self-isolate. Researchers took 30 samples of hotels spread across Jakarta, and Tangerang and have self-isolation facilities, making this website using QGIS technology which has Geographic Information System technology. [ABSTRACT FROM AUTHOR]

The ability to solve problems is very important that students must have in solving a problem, and be able to develop it in a better direction. This study aims to analyze the ability to solve problems in the pythagorean theorem material based on the APOS theory in grade VIII students of SMP Muhammadiyah 7 Surakarta in terms of learning motivation. This research uses qualitative descriptive method. Data collection techniques use questionnaires, written tests, and interviews. The results of this study show that student learning motivation is in the high, medium, and low categories. Students with high learning motivation reach all the stages of APOS theory and can solve problems correctly. Students with medium learning motivation reach the stage of APOS theory, that are as action, processes and objects. As well as being able to solve the problem correctly. At low learning motivation, it reach the stage of APOS theory, that are as action and processes. The subject has not been able to answer the questions correctly. [ABSTRACT FROM AUTHOR]

Mining activities and community activities around the Way Umpu River have the potential to be the main source of the decline in the water quality of the Way Umpu River. Therefore, to determine the level of pollution in the Way Umpu River, it is necessary to test the quality of river water using several chemical and physical parameters such as TSS (Total Suspended Solid), DO (Dissolved Oxygen), BOD (Biological Oxygen Demand), COD (Chemical Oxygen Demand), and Phosphate. The study aims to study the differences in levels of TSS, DO, BOD, COD, and phosphate in river water before and after the mining location. The research is an observational study. Samples were taken from two points, namely the upstream (before the mining location) and the downstream (after the mining location). The average result after the analysis test is then compared with the river water quality standard in accordance with the provisions of Government Regulation no. 11 of 2012 concerning class III river water quality standards. There is no significant difference before and after mining location for the average levels of TSS, DO, BOD, and Phosphate parameters (p-value > 0.05). In the COD parameter, there is a significant difference (p-value < 0.05). Overall, the average yields of TSS, DO, BOD, COD, and Phosphate after the mining location have met the quality standards set out in accordance with Government Regulation. Therefore, it can be concluded that mining activities and community activities around the Way Umpu River have not completely decreased the water quality of the Way Umpu River in the last four years. [ABSTRACT FROM AUTHOR]