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A review on efficient electromagnetic interference shielding materials by recycling waste—a trio of land to lab to land concept
2021
Verma, Sarika | Mili, Medha | Dhangar, Manish | Jagatheesan, Krishnasamy | Paul, Sriparna | Bajpai, Harsh | Vedanti, Nimisha | Mallik, Jyotirmoy | Khan, Mohammed Akram | Bhargaw, Hari Narayan | Hashmi, Sayed Azhar Rasheed | Srivastava, Avanish Kumar
The materials used in electrical and electronic applications have great importance and broader applications, but they have severe electromagnetic interference (EMI). These materials have extensive applications in broadcasting, medical industries, research, defence sectors, communication and similar fields. The EMI can be addressed by using effective EMI shielding materials. This review presents a detailed, comprehensive description for making electromagnetic interference shielding material by recycling various wastes. It starts with highlighting the overview of electromagnetic interference shielding (EMI) and its theoretical aspects. It provides a comprehensive and detailed understanding of recent trends in the novel approaches towards fabricating EMI shielding from industrial waste, agricultural waste and other miscellaneous wastes. This paper critically reviews the works related to the recycling of wastes like red mud (waste from the aluminium refining industry), ground tyre rubber, tea waste (biowaste) from tea industries, bagasse (waste from sugar cane industry), peanut and hazelnut shells (agricultural waste), waste tissue paper and polyethylene and other miscellaneous wastes like hydrocarbon carbon black and ash for the fabrication of highly effective electromagnetic (EM) interference shielding materials. Highly effective results have been reported using red mud showing maximum efficiency of 51.4 dB in X-band range, various agricultural waste displaying reflection loss of up to − 87.117 dB (in the range 0.01 to 20 GHz) and miscellaneous waste giving EMI SE of 80 dB in X-band frequency. A separate section is dedicated to emphasizing future work and recommendations.
Afficher plus [+] Moins [-]Estimation of the water footprint of kiwifruit: in the areas transferred from hazelnut to kiwi
2022
Bilge Ozturk, Gulsah | Ozenen Kavlak, Mehtap | Cabuk, Saye Nihan | Çabuk, Alper | Cetin, Mehmet
Agriculture is the largest consumer of freshwater and plays a critical role in addressing global water scarcity. While numerous studies have focused on the water footprint (WF) of various agricultural products, little attention has been paid to changing cropping patterns and their impact on WF. Here, we investigate the impact of conversion from hazelnut fields to kiwi orchards on green, blue, and gray WF between 2010 and 2021 in Ordu, Turkey. Our results show a total increase of 803,901 tons WF for all green, blue, and gray WF. Compared to the previous situation, changing the agricultural product and growing kiwifruit on previously established hazelnut fields increases green WF by 372,106 tons and blue WF by 334,167 tons. Thus, the change of cultivation pattern could significantly contribute to the water scarcity in the area, and at the same time, the increase in WF. Although kiwi cultivation might be advantageous economically, this economic benefit might be an ecological disadvantage as kiwi production is highly dependent on limited blue water resources. Therefore, it is suggested to further promote the rain-fed product, the hazelnut.
Afficher plus [+] Moins [-]Metal concentration and health risk assessment of wild mushrooms collected from the Black Sea region of Turkey
2020
Sarikurkcu, Cengiz | Akata, Ilgaz | Guven, Gulsen | Tepe, Bektas
Mushrooms are rich sources of organic nutrients (especially proteins). However, they can excessively accumulate metals in their fruiting bodies that pose a risk to human health. The aim of this study was the determination of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn contents, daily intake, and health risk index values of some mushroom species collected from the eastern Black Sea region of Turkey (Arsin, Trabzon). The samples were collected from hazelnut gardens that are free from industrial pollution and have a low population density. As a result of elemental analysis, it was determined that the concentration ranges of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn in the mushrooms were as follows: 0.29–9.11, 0.04–3.70, 0.01–8.29, 0.18–20.82, 3.1–79.8, 5.2–673.0, 14.9–752.0, 63.0–7769.0 mg/kg dry weight. Daily intakes of all the elements were found to be below the reference dose in Fistulina hepatica, Hydnum repandum, Macrolepiota procera, and Tapinella atrotomentosa. Amanita caesarea, Agrocybe praecox, Amanita vaginata, Cantharellus cibarius, Craterellus cornucopioides, Daedalea quercina, Gymnopus dryophilus, Ganoderma lucidum, and Infundibulicybe gibba were found to have high risk index values especially with respect to Cd, Co, and Pb. According to Pearson correlation analysis, the correlations between Fe–Mn (0.840, p < 0.01) and Pb–Ni (0.7540, p < 0.01) couples are significant.
Afficher plus [+] Moins [-]Biosorption of Tetracycline and Cephalexin onto Surfactant-Modified Waste Biomass Using Response Surface Methodology and Ecotoxicological Assessment: Phytotoxicity and Biotoxicity Studies
2022
Guler, Ulker Asli | Solmaz, Betül
Waste hazelnut shell was modified using hexadecyltrimethylammonium (HDTMA) to remove tetracycline and cephalexin from water and minimize the residual antimicrobial activity of tetracycline and cephalexin. Response surface methodology (RSM) was used to determine the effect of solution pH (3.0–6.0–9.0), initial pollutant concentration (5–52.5–100 mg/L), contact time (5–92.5–180 min), and temperature (20–35–50°C) on the removal efficiency of tetracycline and cephalexin. Comparison between model results and experimental data gave a high coefficient of determination (R²TC 0.94, R²CPX 0.99). The predicted removal efficiency of tetracycline and cephalexin by the RSM design was 37.34% and 83.07%, respectively. Langmuir, Freundlich, D-R, and Temkin isotherm were applied to equilibrium data. The Qᵒ values for tetracycline and cephalexin were 6.97 and 47.77, respectively. Acute tests were performed before and after biosorption using Lepidium sativum and Daphnia magna. IC₅₀, LC₅₀, and toxic unit were determined. IC₅₀ values for root and shoot for tetracycline and cephalexin were 50 mg/L, 50 mg/L, 140 mg/L, and 270 mg/L, respectively. LC₅₀ values of tetracycline and cephalexin were 58 mg/L and 37 mg/L for 48 h, respectively. There was a large decrease in mortality (%) after biosorption. This biosorbent was effective in the biosorption of tetracycline and cephalexin and in reducing toxicity.
Afficher plus [+] Moins [-]Geographic information system–assisted site quality assessment for hazelnut cultivation using multi-criteria decision analysis in the Black Sea region, Turkey
2022
Tercan, Emre | Dengiz, Orhan | Özkan, Barış | Dereli, Mehmet Ali | Öztekin, Yeşim Benal
Developing land suitability models for strategically critical agricultural products to expand sustainable agricultural policies and sensitive agriculture management has become a significant trend. This study aims to improve a unique land suitability model for hazelnut cultivation by applying the criteria set (7 main criteria, 35 sub-criteria) including qualitative and quantitative reasons, integrated fuzzy analytic hierarchy process, inverse distance weighting, multi-criteria decision analysis, geographic information system, and weighted linear combination approaches. The model developed in the present study was applied and tested in Ünye District of Ordu Province, where hazelnut production in the Eastern Black Sea region of Turkey is an important economic activity. While 71.17% of the study area is classified as very highly suitable, highly suitable, and moderately suitable, 28.83% of the study area has marginally suitable and unsuitable properties for hazelnut cultivation. Generally, it was determined that the coastal parts of the study area were the most suitable areas for hazelnut growing. The hazelnut land suitability model’s two main criteria impacting the final score values are climatic and topographic conditions, respectively. Heavy metal pollution and physical, chemical, and fertility conditions related to soil properties followed these, respectively. The first ten sub-criteria with the highest weight value were determined as elevation, annual average temperature, annual average precipitation, aspect, annual average relative humidity, nickel (pollution), slope, annual average maximum temperature, lead (pollution), and soil depth, respectively. Existing hazelnut cultivation areas were used to test the model. Of the existing cultivation areas, 75.59% coincided with the very highly suitable, highly suitable, and moderately suitable classes presented in this study, while 17.15% were in marginally suitable and 7.26% in unsuitable classes. The study results reveal that the hazelnut land suitability model developed is suitable in mild climate conditions. Using this model as a general transition model will be beneficial to test it in areas containing similar climatic conditions and various soil properties. This study will create a rational background in ensuring the sustainable food production system and security, agricultural land use planning, strategic planning and management of the hazelnut plant, increasing agricultural productivity and income, and the ecosystem.
Afficher plus [+] Moins [-]Adsorption of U(VI) from aqueous solution by using KMnO4-modified hazelnut shell activated carbon: characterisation and artificial neural network modelling
2021
Zhu, Mijia | Li, Fanxiu | Chen, Wu | Yin, Xianqing | Yi, Zhengji | Zhang, Shuyong
This study is based on U(VI) removal from wastewater by KMnO₄-modified hazelnut shell activated carbon (KM–HSAC) using adsorption technology. A characterisation study of KM–HSAC was conducted through scanning electron microscope and energy-dispersive X-ray spectroscopy (EDS) analysis. The rough surface of KM–HSAC contains many irregular microspores. The EDS pattern confirmed the U(VI) adsorption on the KM–HSAC. A batch study experiment gave optimum results for U(VI) at pH 6, contact time of 160 min, initial U(VI) concentration of 155.56 mg/L and KM–HSAC dosage of 4 g/L, with a maximum adsorption capacity of 22.27 mg/g. The prediction performance of artificial neural network models was validated through the low values of statistical error (2.708 and 8.241 for RMSE of training and testing data, respectively) and the high determination coefficient value (0.987 and 0.906 for training and testing data, respectively). Experimental results suggest that KM–HSAC has a high potential for the removal of U(VI) from wastewater.
Afficher plus [+] Moins [-]Biosorption of Methylene Blue from Aqueous Solutions by Hazelnut Shells: Equilibrium, Parameters and Isotherms
2008
Doğan, Mehmet | Abak, Harun | Alkan, Mahir
This paper presents a study on the batch adsorption of a basic dye, methylene blue (MB), from aqueous solution onto ground hazelnut shell in order to explore its potential use as a low-cost adsorbent for wastewater dye removal. A contact time of 24 h was required to reach equilibrium. Batch adsorption studies were carried out by varying initial dye concentration, initial pH value (3-9), ionic strength (0.0-0.1 mol L⁻¹), particle size (0-200 μm) and temperature (25-55°C). The extent of the MB removal increased with increasing in the solution pH, ionic strength and temperature but decreased with increase in the particle size. The equilibrium data were analysed using the Langmuir and Freundlich isotherms. The characteristic parameters for each isotherm were determined. By considering the experimental results and adsorption models applied in this study, it can be concluded that equilibrium data were represented well by Langmuir isotherm equation. The maximum adsorption capacities for MB were 2.14 x 10⁻⁴, 2.17 x 10⁻⁴, 2.20 x 10⁻⁴ and 2.31 x 10⁻⁴ mol g⁻¹ at temperature of 25, 35, 45 and 55°C, respectively. Adsorption heat revealed that the adsorption of MB is endothermic in nature. The results indicated that the MB strongly interacts with the hazelnut shell powder.
Afficher plus [+] Moins [-]A critical approach to the toxic metal ion removal by hazelnut and almond shells
2018
Cataldo, Salvatore | Gianguzza, Antonio | Milea, Demetrio | Muratore, Nicola | Pettignano, Alberto | Sammartano, Silvio
The adsorption capacity of ground hazelnut (HS) and almond (AS) shells towards Pb(II) and Cd(II) has been studied at pH = 5, in NaNO₃ and NaCl ionic media, in the ionic strength range 0.05–0.5 mol L⁻¹. Kinetic and equilibrium experiments were carried out by using the Differential Pulse Anodic Stripping Voltammetry technique to check the amount of the metal ion removed by HS and AS materials. Different kinetic and equilibrium equations were used to fit experimental data and a statistical study was done to establish the suitable model for the data fitting. A speciation study of the metal ions in solution was also done in order to evaluate the influence of the ionic medium on the adsorption process. TGA-DSC, FT-IR, and SEM-EDX techniques were used to characterize the adsorbent materials. The mechanism of metal ions adsorption was explained on the basis of the results obtained by the metal ions speciation study and the characterization of materials.
Afficher plus [+] Moins [-]Authentication of an Italian PDO hazelnut (“Nocciola Romana”) by NIR spectroscopy
2018
Biancolillo, Alessandra | De Luca, Silvia | Bassi, Sebastian | Roudier, Léa | Bucci, Remo | Magrì, Andrea D. | Marini, Federico
Common hazelnuts are widely present in human diet all over the world, and their beneficial effects on the health have been extensively investigated and demonstrated. Different in-depth researches have highlighted that the harvesting area can define small variations in the chemical composition of the fruits, affecting their quality. As a consequence, it has become relevant to develop methodologies which would allow authenticating and tracing hazelnuts. In the light of this, the present work aims to develop a non-destructive method for the authentication of a specific high-quality Italian hazelnut, “Nocciola Romana,” registered with a protected designation of origin (PDO). Thus, different samples of this fruit have been analyzed by near-infrared (NIR) spectroscopy and then classification models have been built, in order to distinguish between the PDO fruits and the hazelnuts not coming from the designated region. In particular, two different classification approaches have been tested, a discriminant one, partial least squares-discriminant analysis, and a class-modeling one, soft independent modeling of class analogies. Both methods led to very high prediction capability in external validation on a test set (classification accuracy in one case, and sensitivity and specificity in the other, all higher than 92%), suggesting that the proposed methodologies are suitable for a rapid and non-destructive authentication of the product.
Afficher plus [+] Moins [-]The hierarchical porous structure bio-char assessments produced by co-pyrolysis of municipal sewage sludge and hazelnut shell and Cu(II) adsorption kinetics
2018
Zhao, Bing | Xu, Xinyang | Zeng, Fanqiang | Li, Haibo | Chen, Xi
The co-pyrolysis technology was applied to municipal sewage sludge (MSS) and hazelnut shell with alkaline activating agent K₂CO₃ under N₂ atmosphere. The innovative bio-char produced by co-pyrolysis had significant physical and chemical characteristics. The specific surface area reached 1990.23 m²/g, and the iodine absorption number was 1068.22 mg/g after co-pyrolysis at 850 °C. Although hazelnut shell was a kind of solid waste, it also had abundant cellulose resource, which could contribute to porous structure of bio-char during co-pyrolysis with MSS and decrease total heavy metals contents of raw material to increase security of bio-chars. Meanwhile, the residual fractions of heavy metals in bio-char were above 92.95% after co-pyrolysis at 900 °C except Cd to prevent heavy metals digestion, and the bio-char presented significant immobilization behavior from co-pyrolysis technology. Moreover, the yield and the iodine absorption number of bio-chars under different process variables were analyzed, and it was confirmed that appropriate process variables could contribute the yield and the iodine absorption number of bio-char and prevent to etch pore structure excessively to collapse. The changes of surface functional groups and crystallographic structure before and after co-pyrolysis were analyzed by FTIR and XRD, respectively. The hierarchical porous structure of bio-char was presented by SEM and N₂ adsorption-desorption isotherm. The Cu(II) adsorption capacity of the bio-char was 42.28 mg/g after 24 h, and surface functional groups acted as active binding sites for Cu(II) adsorption. Langmuir model and pseudo-second-order model can describe process of Cu(II) adsorption well.
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