• Proceedings of the Safety Management and Science Conference
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• 2007.04a
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• pp.197-203
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• 2007

Teshima has been a quiet and beautiful island, but started to be imaged as an "island of wastes" because of the 600,000 tons of industrial wastes thrown there illegally. Now it symbolizes the problem of industrial wastes in Japan. Teshima development company, an industrial waste disposer, started to dispose industrial wastes illegally in the west side of the island, since the late 1970s. Hyogo Police Station exposed this illegal act, and arrested 6 persons of the company, including its president, in charge of having violated the Waste Disposal and Public Cleansing Law in 1991. This illegal disposition has continued for 13years until it was exposed by the police. Teshima case of industrial wastes are introduced in this paper.

• Journal of Powder Materials
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• v.30 no.6
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• pp.528-535
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• 2023

Since their initial development in 2012, triboelectric nanogenerators (TENGs) have gained popularity worldwide as a desired option for harnessing energy. The urgent demand for TENGs is attributed to their novel structural design, low cost, and use of large-scale materials. The output performance of a TENG depends on the surface charge density of the friction layers. Several recycled and biowaste materials have been explored as friction layers to enhance the output performance of TENGs. Natural and oceanic biomaterials have also been investigated as alternatives for improving the performance of TENG devices. Moreover, structural innovations have been made in TENGs to develop highly efficient devices. This review summarizes the recent developments in recycling and biowaste materials for TENG devices. The potential of natural and oceanic biowaste materials is also discussed. Finally, future outlooks for the structural developments in TENG devices are presented.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.236-241
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• 2024

Due to the recent emphasis on carbon neutrality and environmental regulations, the global electric vehicle (EV) market is experiencing rapid growth. This surge has raised concerns about the recycling and disposal methods for EV batteries. Unlike traditional internal combustion engine vehicles, EVs require unique and safe methods for the recovery and disposal of their batteries. In this process, predicting the lifespan of the battery is essential. Impedance and State of Charge (SOC) analysis are commonly used methods for this purpose. However, predicting the lifespan of batteries with complex chemical characteristics through electrical measurements presents significant challenges. To enhance the accuracy and precision of existing measurement methods, this paper proposes using a Long Short-Term Memory (LSTM) model, a type of deep learning-based recurrent neural network, to diagnose battery performance. The goal is to achieve safe classification through this model. The designed structure was evaluated, yielding results with a Mean Absolute Error (MAE) of 0.8451, a Root Mean Square Error (RMSE) of 1.3448, and an accuracy of 0.984, demonstrating excellent performance.

• Journal of Environmental Science International
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• v.29 no.11
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• pp.1015-1024
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• 2020

Using the waste(sand wastr and boiler ash) in fluidized bed inciverator, lightweight aggregate concrete was produced and a recycling plan was prepated. The first, the result of the leaching test shows that the waste fluid sand and boiler ash did not exceed the effluent standard. This indicates that there is no harmful effect for recycling. The second, in the lightweight aggregate test using waste fluid sand and boiler ash, the sample that combined cement, waste fluid sand, and sand showed the highest compressive strength, and the mix proportion was 10: 7: 3. Lightweight aggregate concrete that combined cement, waste fluid sand, boiler ash, and sand had a low compressive strength by and large. The third, the same results were identified in the relation between the content of SiO₂ and that of Na₂O. As the SiO₂ content is lowered, the overall viscosity and plasticity of the concrete also decrease, which is not a good condition to form concrete. As for Na₂O, as the content increases, the viscosity of the sample and the viscosity of the cement are remarkably lowered, and the strength of the finished concrete is lowered. Therefore, it was concluded that the higher the content of SiO₂ and the lower the content of Na₂O, the more suitable it is to mix with cement to produce concrete. Fourth, from the fluidized bed incinerator currently operated by company A in city B, a total of 14,188 tons/year were discharged as of 2016, including 8,355 tons/year of bottom ash (including waste fluid sand) and 5,853 tons/year of boiler ash. The cost for landfill bottom ash and boiler ash discharged is 51,000 won/ton, and the total annual landfill cost is 723,588,000 won/ year. Assuming that the landfill tax to be applied from the year 2018 is about 10,000 won/ton, and if there is no reduction in waste disposal charge, an additional landfill tax of 141,880,000 won/year will be imposed. Consequently, the sum total of the annual landfill cost will be 865,468,000 won/year. Therefore, if the entire amount is used for recycling, the annual savings of about 8.7 billion won can be expected.

• Resources Recycling
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• v.28 no.3
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• pp.15-20
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• 2019

The recovery of struvite using nitrogen and phosphorus in wastewaters is useful for prevention of eutrophication and use as fertilizer, but there are theoretical and technical issues to be resolved. Through the detailed literature review, this study discusses the possible reasonable prediction of struvite formation reaction by setting a feasible reaction equation with some theoretical considerations. In a technical aspect, the purity of struvite in solid precipitates can be promoted by excluding Ca in an effective way. As for the struvite reaction prediction issue, selection of proper equilibrium reaction as well as its reaction equilibrium coefficient is significant in the neutral and basic pH regions. The equilibrium reaction agrees well with the experimental batch test results. Considering the charge balance of the ions, the pH drop along struvite formation in a diluted solution can be predicted. Also, improvement of struvite purity through elimination of Ca can be expected by providing a highly concentrated ${NH_4}^+-N$ relative to ${HPO_4}^{2-}-P$ because ${NH_4}^+$ can enhance the thermodynamic driving force toward favorable struvite formation. Even though the phosphate reacts rapidly with Ca to form a solid precipitate, the thermodynamic driving force due to the high ${NH_4}^+$ activity can dissociate the phosphate-calcium precipitates and produce struvite.

• Journal of Aquaculture
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• v.16 no.2
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• pp.76-83
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• 2003

To improve the efficiency of removal of bacteria and virus with DynaSand Filters used for treatment of recycling wastewater from aquaculture, effect of biofilm formation on bacterial transport through coated sand was estimated. At the neutral pH (pH 7.0), the coated sand was positive of zeta potential (surface charge). Column experiments were also carried out to test the effect of uncoated sand as well as coated sand with Al and Fe. The coated sand influenced more significantly the surface properties, adsorption and transport than the uncoated sand. The leaching batch system investigated for synthetic water showed concentrations of 7.47, 4.80, 20.89 and 7.23 mg/L for the uncoated sand, coated sand with Al, Fe and Al+Fe, respectively. Hence there are significant differences among the tested coatings with reference to bacterial transport and surface properties.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.99-103
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• 2006

Use of recycled fibers in papermaking has been increased for economical and environmental reasons. Recycled panels are major liber resources for brown grades and newsprints. Since the recycled fibers have disadvantageous properties as raw materials for papermaking it is of great importance to optimize the use of these recycled fibers. OCC (Old Corrugated Containers) is the major fiber source for linerboards and corrugating mediums that require diverse specification in strength properties. Many studies have been focused to overcome the problems of strength reduction of brown grades when recycled fibers are used as raw materials. The problem of strength loss for papers made from recycled fibers is closely associated with the increased amount of fines in recycled fibers and hornification of fibers. Fines contained in the recycled fiber resources cause problems not only in paper properties but also in process runnability. This shows that the optimal management and proper use of fines in recycling papermaking system are critical to get most benefits of using recycled fibers. In this study some approaches for optimal use of fiber fines in recycled paper mill have been investigated. Stock samples, prepared in the laboratory and obtained from a recycling plant were used. Fractionation of these samples was made using Sweco screen. And the effect of the addition of polyelectrolytes including cationic PAM and PEI on drainage and retention was evaluated. Different methods of polymer addition were compared to find the most effective ways of treating recycled fiber stocks with polyelectrolytes. Addition of polyelectrolytes to the short fiber fraction was most effective in retention and drainage. The influence of the charge and molecular weight of these two polymers has been examined and discussed.

• Resources Recycling
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• v.16 no.6
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• pp.61-67
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• 2007

Teshima is a quiet and beautiful island, but started to be imaged as an "island of wastes" because of the 600,000 tons of industrial wastes thrown there illegally. Now it symbolizes the problem of industrial wastes in Japan. Teshima development company, an industrial waste disposer, started to dispose industrial wastes illegally in the west side of the island, since the late 1970s. Police Station exposed this illegal act, and arrested 6 persons of the company, including its president, in charge of having violated the Waste Disposal and Public Cleansing Law in 1991. This illegal disposition has continued for 13years until it was exposed by the police. Teshima case of industrial wastes are introduced in this paper.

• Resources Recycling
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• v.13 no.2
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• pp.24-32
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• 2004

Solvent extraction equilibria of Gd with PC88A from chloride solutions were analyzed by considering chemical equilibria. phase equilibria, mass and charge balance equations. The following solvent extraction reaction and equilibrium constant were evaluated from the experimental data performed in this study. $Gd^{3+}$ $+2H_2$$A_2$,$or=GdA_3$HA.or+3 $H^{+}$ , K=3.3 A procedure was suggested to calculate the initial concentration of chloride ion from initial pH and initial concentration of Gd. By applying ionic equilibria, the distribution of Gd complexes with Gd and HCl concentration was obtained. The predicted distribution coefficients of Gd agreed well with the experimental results.

• Resources Recycling
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• v.26 no.5
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• pp.48-53
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• 2017

During steelmaking on EAF, 1 ~ 2% of dust is generated. EAF Dust contains 20 ~ 30% of Zn and Fe. Dust contained in Off-gas is passed through combustion tower and cooling tower, and then captured in bag filter. About 15 wt.% of dust is dropped at the bottom of Combustion tower by its specific gravity, which was also carried out to recycle company with more higher charge than Bag filter dust. This study is focused on the combustion tower dust, and seperation as a function of operation period and particle size. As a result, Zn and Fe content of dust is more affected by size factor than operation period.