ABSTRACT Cooking oil is an indispensable ingredient in everyday family cooking. The oil after use is often discharged directly into wastewater systems, leading to risks of environmental pollution, water pollution, clogging of drainage systems... In recent years, water hyacinth plants have been considered weeds, floating on rivers, canals, ponds and lakes, obstructing the circulation of boats and preventing water flow. Water hyacinth plants are often found in large rivers and almost no one cares about their uses, making them truly wasteful. Realizing the flexibility of water hyacinth when dried, it can be woven into pieces with good absorbent properties, our team has researched using water hyacinth as a material to absorb used cooking oil that is discarded into the environment. school. The research uses the main methods of experimental method and sample analysis method in its research. The result is that a product that absorbs discarded cooking oil scum is formed and is tested for cooking oil contaminated water with results consistent with QCVN 14:2008/BTNMT. The purpose of the research is to find effective products to absorb discarded cooking oil to save costs and contribute to environmental protection. The problem of using naturally available materials to create products that absorb cooking oil scum at the same time solves two current environmental problems. The research is a preliminary result, so there are still many shortcomings. We hope that in the future there will be further research to make the product more and more perfect

ABSTRACT Nowadays, parents' needs are increasing to choose toys, especially painting colors, that are both beautiful, ensure their children's health, and are also environmentally friendly. In the production of industrial painting colors, waste from steps in the watercolor production line, if not treated to meet environmental standards according to regulations, will become a huge hazard to the environment and human health. human. Including causing skin, eye, digestive, and respiratory allergies. Causes poisoning, disease, cancer... Destroys the aquatic environment, trees, pollutes rivers and lakes. When building an industrial painting colors production line and putting it into use, if you do not think about solutions to treat wastewater from the production process, it will not be able to operate long term. Wastewater from color factories is mainly heavy metals contained in painting colors such as lead carbonate, oxide, and metal salts containing cadmium chromate. These substances cause mass death of organisms in the water, and polluted water cannot be used for agriculture. This research uses two main methods: experimental research to create products; combined with the questionnaire survey method to get customer opinions after using the painting colors test. Research results show that painting colors products made from fruits and vegetables combined with beeswax and coconut oil are very eye-catching and receive positive feedback from customers. With the im of protecting children in the future and responding to the green environmental message in the world, we hope that safe painting colors products from vegetables and fruits will be popularized in the community in the future. Keywords: vegetables, painting colors, environmental protection, safe products, beeswax.

Abstract: Urban agriculture is a highly concerned issue during the period of rapid urbanization in Vietnam. Research aims to propose a cultivation process for cultivating oyster mushrooms, utilizing coffee grounds from coffee businesses as a resource. This approach promotes circular economy principles, generating economic benefits for households while protecting the environment and being suitable for urban areas. The study conducted experiments on grey oyster mushrooms using different mixtures of coffee grounds and rubber wood sawdust at the following ratios: 0%, 25%, 50%, 75%, and 100% coffee grounds/rubber wood sawdust, filled into bags with a weight of 1.2kg. The research results showed that disease infection rates were mild in the 0% and 25% mixture ratios, while the remaining ratios exhibited moderate to severe infection levels. The highest mushroom yield was observed in the mixture ratio of 25% coffee grounds, with an average number of mushroom ears per bag reaching 29.7grams/bag, the dry weight is 63.8 grams/bag, with an average size ranging from 3 to 14 cm and a moisture content of 79.5%. The fastest colonization speed on the substrate is achieved by 25%, 50% coffee grounds blend, which fully colonizes the bag in a period of 25 to 35 days, the shortest time compared to the 75% and 100% coffee grounds blends, which take 40 to 45 days. The experimental results show that the 25% coffee grounds: 75% rubber sawdust blend is suitable for urban mushroom cultivation models and can be expanded on a large-scale farm, contributing to minimizing environmental pollution, utilizing limited urban land area, and providing high economic efficiency.

The present study aims to investigate the possibility of domestic wastewater treatment using biological system combined with chemical-physical processes, including Upflow Sludge Blanket Filtration (USBF) technology and PolyAluminium Chloride (PAC). Experimental results showed that the added PAC content plays an essential role in improving the treatment efficiency and reached National Technical Regulation on domestic wastewater QCVN 14:2008/BTNMT (Column A). With Jar-test results, the optimal pH of 7.0 and the PAC dosage of 170 mg/L were recorded with the highest removal efficiencies for suspended solids and organic matter. In the modified USBF bioreactor, the findings illustrated the pollutant removal efficiencies such as Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and Suspended Solids (SS) were equal to 96.2 ± 1.4%, 85.8 ± 4.4% and 99.3 ± 2.1%, respectively. The parameters of BOD5 and SS met QCVN 14:2008/BTNMT - Column A. In the future, this advanced filtration technology can be helpful for wastewater reclamation and reuse to cope with water scarcity.

This work presents a benchmarking study between Lagamine, an in-house developed finite element (FE) code, and COMSOL Multiphysics® (Comsol) commercial software in thermal analyses to investigate their capability in modeling complex manufacturing processes. For this purpose, two case studies, including a NAFEMS benchmark for heat transfer with convection and a Directed Energy Deposition (DED) of a bulk sample, were used as test cases. The simulation models using Lagamine and Comsol solvers for each case were described. The underlying algorithms and theories, as well as the soft-ware development, are investigated. The computational results indicate slight differ-ences between Lagamine and Comsol solutions in both case studies. For the NAFEMS test case, the results obtained with Comsol solver appear to be less dependent on the mesh size than those obtained with Lagamine. For the DED test case, within the chosen configurations of Lagamine and Comsol codes, the maximum difference in the highest peak temperatures obtained from the two codes is about 20%. From an engineering point of view, it is suggested to determine parameters of the FE model consistently with the selected FE code to provide the best match with experimental observations.

The study was undertaken to compare the lead accumulation and removal of Dracaena sanderiana, Dracaena reflexa, and Dracaena deremensis on artificial lead solutions to apply plants in lead pollution treatment. The experiment consisted of 6 treatments corresponding to 3 investigated species of Dracaena. Each treatment was grown on 2 types of solution with Pb and without Pb used as control. The results indicated that the growth of D. sanderiana, D. reflexa, and D. deremensis was not affected at Pb concentrations of 100 ppm. All three plant species had the ability to absorb and accumulate Pb. In which D. sanderiana was a typical lead excluder because the lead concentration in roots (1952.14 mg/kg), shoots (221.78 mg/kg), and leaves (166.46 mg/kg) of the plants were the highest among the three plants tested. The most of lead accumulated in the root, and transportation of lead in D. sanderiana, D. reflexa, and D. deremensis from root to shoot was restricted. Besides, the highest % removal of Pb was found at D. sanderiana (93.16%) and the minimum of 66.77% at D. reflexa. D. sanderiana is the best choice among the three Dracaena species used for phytoremediation of lead contaminated wastewater.

Heavy metals are the most dangerous substances in the environment, have caused deleterious effect not only to the environment but also to the public’s health. Different studies have demonstrated that plants have a high removal capacity for lead ions from pollution sources. However, these plant species were rather limited. Thus, the project aimed to find out plant species that represent its lead removal ability to reduce environmental pollution. The experiment was carried out factorially as a randomized complete design in hydroponic systems with four treatments (0, 100, 200, and 300 mg/l of Pb) and three replications. The results indicated that the growth of the Dracaena sanderiana plant is well in Pb concentration of 100 mg/l, with less growth while the increasing lead concentration of 200 mg/l and 300 mg/l. The amount of lead in the water of three treatments 100 mg/l, 200 mg/l, and 300 mg/l after 30 days of the experiment decreased by 91.5%, 86.8%, and 86.4%, respectively. It was found that Dracaena sanderiana exhibited high lead treatment efficiency in the water. Moreover, results showed that the accumulation of lead in the roots of Dracaena sanderiana is quite large with treatments of 100 mg/l, 200 mg/l, and 300 mg/l lead concentrations were 5073.8 mg/kg, 5134.0 mg/kg, 7054.0 mg/kg, respectively. In contrast, the ability to lead accumulation in plant leaves and stems is lower. cultivated in hydroponic systems with four treatments and three replications. Four levels of Pb(NO3)2 (0, 100, 200, and 300 ppm) were used. The monitoring indicators include the contents of lead in water, the growth target of Dracaena sanderiana, and the accumulation of lead contents in different organs of Dracaena sanderiana. The results indicated that: the growth of the Dracaena sanderiana plant is well in Pb concentration of 100 ppm, with less growth while the increasing lead concentration of 200 ppm and 300 ppm. The amount of lead in the water of three treatments 100 ppm, 200 ppm, and 300 ppm after 30 days of the experiment decreased by 91.5%, 86.8%, and 86.4%, respectively. It was found that Dracaena sanderiana exhibited high lead treatment efficiency in the water. Moreover, results show that the accumulation of lead in the roots of Dracaena sanderiana is quite large with treatments of 100 ppm, 200 ppm, and 300 ppm lead concentrations were 5073.8 mg/kg, 5134.0 mg/kg, 7054.0 mg/kg, respectively. In contrast, the ability to lead accumulation in plant leaves and stems is much lower.

Cordyceps has long been considered as a valuable medicinal herb known to possess numerous biological activities, including anti-microbial, anti-cancer, anti-metastasis and immunomodulatory effects. With its benefits, many studies on optimizing the cultivation and production of C. militaris have been carried out. In addition, extraction methods have also been improved to intense efficiency extract the medicinal substances contained in this rare fungi. In this study, the aim was to optimize the process of C. militaris extraction from fruiting bodies based on 17 experimental data using water extraction method. The factors that affects to the extraction productivity such as: extraction temperature, extraction time and water/fungi ratio were investigated within a certain range. The experiments were arranged according to the Box-Behnken design, and then the results was optimized by Design expert software (version 13). In the optimal condition, the maximum productivity can be up to 32.23% with the extraction temperature is at 98oC, the water/fungi ratio is 18:1 and the extraction time is 4 hours.

In the new era, paper is still the main source of raw materials for daily life and production activities. Therefore, the research team explored recycling paper from bagasse to reduce waste and limit the depletion of available resources. The main material is bagasse with binders of aloe vera, corn starch, and CaCO3 in certain proportions to create paper products. From the methods of data collection, experiment, quality control, and meta-analysis to make paper from sugarcane applied to daily life. The disintegration test showed about three hours of paper dissolving in water. The product is tearable and has good adhesion. The product is handmade, so the thickness can be adjusted depending on the purpose of use. The product has a certain curvature and high strength. In addition, it is possible to create from this recycled paper into products that are applied in life such as decorative cards, bags, etc.

Research results show that compost was created at the rate of C / N: 25/1 by mixing ingredients 2.5 grams of cow manure, 3g of organic waste, 0.01g of coir based on calculation of content. C and N in each material; With the humidity of 60% based on the calculation of the moisture content from the compost materials combined with the amount of water to add is 670ml, from which a Compost fertilizer has been produced. Determination of the optimal values for the mixratio and function has been verified on experimental crops. Research also shows that the use of probiotics in composting will shorten the compost time, limit the odor escaping from the compost.

SARSCOV-2 virus and new strains have been spreading in most countries and regions around the world, the COVID-19 epidemic it causes has infected millions of people, the urgent need is to prevent their spread. On the market there are many types of hand wash equipment automatically spray disinfectant solution used with many different sensors and operating principles, but most are still using AC power. In this topic, we design automatic hand washing equipment by applying the transmitter and receiver principle of the moving infrared sensor circuit and delay relay circuit to detect someone appearing in the observation area, click activating the MP3 reader circuit plays the “5K” propaganda sound about Covid -19 disease prevention and the position sensor activates the mini-pump to spray the hand-washing gel within a certain detecting distance. We have conducted experiments and completed our projects with devices that use energy from solar cells, through charging circuits and storage batteries with the goal of using renewable energy, minimizing impact of the greenhouse effect.

Corrosion of the bottom of the petroleum tank may lead to a product leak that could cause a fire or explosion resulting in damage to people and the environment, therefore the test of tank bottom corrosion is necessary to be conducted periodically to prevent the occurrence of the above problems. In non-destructive inspection, the Magnetic Flux Leakage (MFL) method relies on the variation of fluxes caused by defects on the surface of materials to detect corrosion, pitting, or imperfections, which is proved quite effectively with low cost. The project was implemented to develop a prototype of the MFL bottom detection device based on the research results in the world to improve corrosion survey capacity in industrial equipment, as well as to improve the expertise in the Research Team of electronics and automation in the fields of magnetic fields and sensors. As a result, an MFL model using permanent magnets and Hall sensors were fabricated. Survey experiments showed that the machine could detect corrosion defects up to 20% of steel wall thickness in the scanning speed range from 500 mm/s to 1130 mm/s. However, to meet the actual survey needs, the team must continue to improve the device in terms of sensitivity, scanning speed, the ability to operate automatically or semi-automatically, and register for a fire safety inspection.