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Copyright of Afyon Kocatepe University Journal of Science & Engineering / Afyon Kocatepe Üniversitesi Fen Ve Mühendislik Bilimleri Dergisi is the property of Afyon Kocatepe University, Faculty of Science & Literature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Mining activities can produce large amounts of heavy metals that are discharged uncontrollably, causing widespread ecosystem pollution. Heavy metal pollution is a serious problem, as heavy metals are toxic and non-degradable, polluting air, water and soil. Although some heavy metals are considered essential for normal physiological functions, concentrations that exceed the prescribed limits can have negative impacts on human health and biota. Exposure to heavy metals can cause toxicity to various tissues, organs and systems such as circulatory, respiratory, endocrine, immune, nervous, urinary and reproductive systems. Due to the differences in toxicity of heavy metals, risk assessment is very important in environmental management. Objective: To describe the probabilistic simulation and sensitivity of health risks due to Nickel and Cobalt deposition around the mine using monte carlo simulation. Methods: The method used in this study was literature review. Data collection was done through searching online databases such as: Pubmed and Science Direct. The keywords used in the article search were "Heavy Metal Toxicity", "Heavy Metal Effects", "Heavy metal risk analysis" and "Monte Carlo Simulation". Inclusion criteria were quantitative or qualitative research, target population was heavy metals Nickel and Cobalt, published in the last 10 years (2013-2023) articles in English and articles in original, fulltext and open access. Exclusion criteria are articles that are not relevant to the topic of discussion. Results: 14 articles were found, of which 3 articles on diseases or health problems caused by nickel, 3 articles on nickel risk analysis, 5 articles on diseases or health problems caused by cobalt, 3 articles on cobalt risk analysis. Conclusion: The environment around the mine shows a high level of toxicity, caused by the presence of heavy metals. This can result in serious environmental pollution and pose a great threat to human health. Chronic exposure to heavy metals can cause various health problems, such as mutagenesis, carcinogenesis, teratogenesis, deformation and organ damage. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop metal-metal composites reinforced with nickel powder using an AA5083 aluminium alloy matrix by powder metallurgy methods and to investigate their properties. In order to analyse the influence of different amounts of nickel particles on the AA5083-Ni composite, specimens were prepared by incorporating nickel at 5%, 10% and 15% by weight. To achieve a uniform distribution of nickel particles, the matrix and composite powders were mixed in ball mills for five hours. These powders were then hot pressed at 500°C under a pressure of 500 MPa for two hours in an argon gas atmosphere to produce the samples. These samples were then tested for microstructure, hardness, density, tensile properties and corrosion behaviour to assess the effect of varying nickel content on the AA5083-Ni metal-metal composites. [ABSTRACT FROM AUTHOR]

Smelting atau peleburan adalah proses mengekstraksi bijih logam murni dari dalam tanah. Dengan kata lain, ini adalah proses pemisahan logam murni dari bijih yang mengandungnya. Untuk mengekstraksi logam, bijih dipanaskan hingga suhu tinggi (di atas titik lelehnya). Untuk proses ini digunakan smelter yang dalam prosesnya akan menghasilkan limbah cair dan limbah padat (sludge). Sludge tersebut biasanya digunakan sebagai penutup lubang bekas tambang. Sludge digunakan sebagai material dasar pembentuk paving block untuk mengurangi limbah dan peningkatan nilai ekonomis. Pada penelitian ini sludge atau lumpur digunakan sebagai pengganti pasir pada produksi paving block. Kadar sludge yang digunakan adalah 10%, 25% dan 50% menggantikan volume pasir, paving block tanpa sludge sebagai benda uji kontrol. Untuk mengetahui mutu paving block yang dihasilkan dilakukan pengujian kuat tekan dan penyerapan. Hasil penelitian menunjukkan bahwa paving block dengan kadar 10% menghasilkan paving block mutu B, pada kadar 25% dan 50% menghasilkan paving block mutu C.

In this study, new poly(HEMA-co-GMA) or pHEMA-GMA support solid structures were prepared to help protein purification. The surface of the prepared pHEMA-GMA building materials was modified by binding different functional groups such as IDA and NTA. Nickel (Ni II) metal ion was passed through the modified cryogel structures. The monolithic cryogel structure chelated with Ni metal was characterized by SEM and FT-IR. GFP fluorescent protein binding studies of metal chelated cryogel structures were performed using UV-vis and fluorescence spectrophotometry. These cryogels were determined to bind 45% and 75% protein by UV-vis and fluorescence spectrophotometry. And these results were supported by visualization with the SDS PAGE method. [ABSTRACT FROM AUTHOR]

In this study, a series of adsorption studies were carried out for the concentration range of 18.08 - 183.95 mg/L Ni(II) in metal plating industry wastewater using graphene oxide. Under constant stirring speed of 200 rpm, optimum pH=6 and optimum contact time was found to be 90 minutes. Temkin isotherm as a pseudo 2nd order kinetic isotherm was chosen as the appropriate model for adsorption kinetics. The optimum amount of graphene oxide as adsorbent was determined as 0.016 mg/L and accordingly the maximum adsorption capacity was 112.56 mg/g. Considering the literature comparisons; it was concluded that graphene oxide can be used as an improvable adsorbent, however, high efficiency cannot be obtained alone, but high efficiency can be achieved with graphene oxide if it is functionalized. [ABSTRACT FROM AUTHOR]

Bimetallic catalysts based on ZSM-5 zeolite modified with ytterbium and nickel have been prepared. The influence of the concentration of ytterbium (1.7-5.0 wt.%) and nickel (1.0-1.5 wt.%) on the acidic, textural and catalytic properties of the zeolite in the reaction of alkylation of toluene with isopropanol in the temperature range of 300-350℃ was studied. It has been shown that the unmodified zeolite HZSM-5 exhibits low selectivity (54.6-58.2%) for isopropyltoluenes (3-IPT, 4-IPT, and 2-IPT) than the modified catalysts. In addition, the content of the valuable 4-IPT isomer does not exceed 44.2%. Modification of HZSM-5 with ytterbium in an amount of 5.0 wt.% leads to an increase in the selectivity for isopropyltoluenes up to 68.7%, and the selectivity for 4-IPT up to 68.8%. Additional modification of the 3%-Yb-HZSM-5 catalyst with nickel in the amount of 1.0 wt.% prevents the formation of 2-IPT and promotes an increase in the yield of 4-IPT. The modified catalysts were characterized by XPA, BET, BJH, and ammonia TPD. Modification, calcination, and successive treatment of the catalyst with air and hydrogen leads to a dispersed distribution of Yb2O3 and metallic nickel oxide nanoparticles in the outer surface and in the pores of the zeolite, which causes a decrease in the specific surface area, total pore volume, and an increase in the fraction of mesopore volume. As a result of the interaction of modifiers with acidic OH groups of the zeolite, the concentration of strong Brønsted acid sites decreases and new, stronger Lewis acid sites form. All this has a decisive effect on the selectivity of 4-IPT formation and the stability of the bimetallic catalyst. The maximum selectivity for 4-IPT on a 3% Yb 1.0% Ni/HZSM-5 bimetallic catalyst is achieved at 3300C and is 71.5% at a toluene conversion of 24.6%. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Hubungan Internasional is the property of Universitas Airlangga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)