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Hydrogen fluoride damage to vegetation from peri-urban brick kilns in Asia: A growing but unrecognised problem?
2012
Ahmad, Muhammad Nauman | van den Berg, Leon J.L. | Shah, Hamid Ullah | Masood, Tariq | Büker, Patrick | Emberson, Lisa | Ashmore, Mike
The rapid urbanisation of many cities in south and south-east Asia has increased the demand for bricks, which are typically supplied from brick kilns in peri-urban areas. We report visible foliar damage to mango, apricot and plum trees in the vicinity of traditional Bull’s Trench brick kilns in Peshawar, Pakistan. Visible injury symptoms, hydrogen fluoride concentrations in air, and foliar fluoride concentrations were all greater in the vicinity of brick kilns than at more distant sites, indicating that fluoride emissions from brick kilns were the main cause of damage. Interviews with local farmers established the significant impact of this damage on their livelihoods. Since poorly regulated brick kilns are often found close to important peri-urban agricultural areas, we suggest that this may be a growing but unrecognised environmental problem in regions of Asia where emission control in brick kilns has not been improved.
Show more [+] Less [-]Heavy metals biosorption mechanism of partially delignified products derived from mango (Mangifera indica) and guava (Psidium guiag) barks
2021
Krishnani, Kishore Kumar | Choudhary, Khushboo | Boddu, Veera Mallu | Moon, Deok Hyun | Meng, Xiaoguang
This paper evaluates the biosorption of toxic metal ions onto the bioadsorbents derived from mango (Mangifera indica) and guava (Psidium guiag) barks and their metal fixation mechanisms. Maximum metal biosorption capacities of the mango bioadsorbent were found in the following increasing order (mg/g): Hg (16.24) < Cu (22.24) < Cd (25.86) < Pb (60.85). Maximum metal biosorption capacities of guava bioadsorbent follow similar order (mg/g): Hg (21.48) < Cu (30.36) < Cd (32.54) < Pb (70.25), but with slightly higher adsorption capacities. The removal mechanisms of heavy metals using bioadsorbents have been ascertained by studying their surface properties and functional groups using various spectrometric, spectroscopic, and microscopic methods. Whewellite (C₂CaO₄·H₂O) has been identified in bioadsorbents based on the characterization of their surface properties using X-ray techniques (XPS and XRD), facilitating the ion exchange of metal ions with Ca²⁺ bonded with carboxylate moieties. For both the bioadsorbents, the Pb²⁺, Cu²⁺, and Cd²⁺ are biosorbed completely by ion exchange with Ca²⁺ (89–94%) and Mg²⁺ (7–12%), whereas Hg²⁺ is biosorbed partially (57–66%) by ion exchange with Ca²⁺ (38–42%) and Mg²⁺ (19–24%) due to involvement of other cations in the ion exchange processes. Bioadsorbents contain lignin which act as electron donor and reduced Cr(VI) into Cr(III) (29.87 and 37.25 mg/g) in acidic medium. Anionic Cr(VI) was not adsorbed onto bioadsorbents at higher pH due to their electrostatic repulsion with negatively charged carboxylic functional groups.
Show more [+] Less [-]Removal of Silver Nanoparticles from Water Environment: Experimental, Mathematical Formulation, and Cost Analysis
2019
Syafiuddin, Achmad | Salmiati, Salmiati | Hadibarata, Tony | Salim, Mohd Razman | Kueh, Ahmad Beng Hong | Suhartono, Suhartono
This paper deals with the comprehensive analysis for the removal of silver nanoparticles (AgNPs) from water environment. A new activated carbon derived from an agricultural waste, water lily mango seed shells, was proposed as a low-cost adsorbent to remove AgNPs. In addition, a new simple kinetic model was mathematically formulated and then tested using primary and secondary experimental AgNP adsorption data on different adsorbents. Moreover, cost analysis for the activated carbon production and removal of AgNPs was also estimated. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and inductively coupled plasma mass spectroscopy (ICPMS) analyses were employed for the characterization. The proposed model evaluation was carried out using six statistical indicators, which are the coefficient of determination (R²), root mean squared error (RMSE), percentage of error in maximum estimated value (Eₘₐₓ), percentage of error in minimum estimated value (Eₘᵢₙ), mean absolute percent error (MAPE), and mean absolute deviation (MAD). This study found that the proposed activated carbon performed a rapid removal with a maximum percentage of up to 97%. It was also interesting to note that the proposed model outperformed existing kinetic models having the same number of parameters. Cost analysis carried out in this study exhibited that the activated carbon was highly economical compared with other water treatment technologies reported elsewhere.
Show more [+] Less [-]A Comparative Study on Activated Carbons Derived from a Broad Range of Agro-industrial Wastes in Removal of Large-Molecular-Size Organic Pollutants in Aqueous Phase [Erratum: November 2015, Vol.226(11), p.386]
2015
Cruz, G. J. F. | Matějová, L. | Pirilä, M. | Ainassaari, K. | Canepa, C. A. | Solis, J. | Cruz, J.F. | Šolcová, O. | Keiski, R. L.
Microporous–mesoporous activated carbons from five different types of agro-industrial wastes were produced using chemical activation with ZnCl₂ and carbonization at mild conditions of 600 °C, comprehensively characterized and investigated for removal of methylene blue (MB) in aqueous solution, a model large-molecular-size organic pollutant. The external part of the mango pit (mango seed husk) was used for the production of activated carbon (AC) for the first time. Despite that the raw agro-materials exhibited significantly different porosity, all activated carbons produced possessed well-developed microporous–mesoporous structures showing high surface areas and micropore volumes. Further, it was revealed that the pore size distribution of raw agro-material is a more important property in development of microporous–mesoporous structure of produced ACs than their overall porosity. All activated carbons produced adsorbed MB, reaching in most cases 100 % removal from the aqueous phase. Adsorption data were fitted well to a pseudo-second-order kinetic model. For MB adsorption, the mesoporosity and the ratio of micropores accessible for MB were the key factors since there exists the size-selectivity effect on MB adsorption due to MB molecular dimensions. The molecular dimensions of MB were estimated via DFT calculations to 1.66 × 0.82 × 0.54 nm, and this parameter was correlated with determined micropore size distributions of activated carbons.
Show more [+] Less [-]Biosorption of Zn (II) onto the Surface of Non-living Biomasses: A Comparative Study of Adsorbent Particle Size and Removal Capacity of Three Different Biomasses
2010
Mishra, Vishal | Balomajumder, Chandrajit | Agarwal, Vijay Kumar
Present research has delineated the biosorption potential of three different nonliving biomasses namely eucalyptus bark saw dust, mango bark saw dust, and pineapple fruit peel with respect to Zn (II) ion removal from liquid phase through batch experiments. The efficacy of Zn (II) ion biosorption onto surface of biosorbents was judged and correlated with biosorbent particle size, surface chemistry, and surface texture. Maximum metal ion uptake capacity, percentage removal, and minimum equilibrium concentration as 1.688 mg/g, 84.4%, and 1.56 mg/l, respectively, was obtained using eucalyptus bark saw dust mediated biosorption followed by mango bark saw dust as 1.028 mg/g, 51.4%, and 4.867 mg/l and pineapple fruit peel as 0.45 mg/g, 22.9%, and 7.71 mg/l, respectively, at a particle size of 0.5 mm. Additionally, present investigation also proved that biosorption efficiency and metal ion interaction with adsorbent surface also depends upon presence of functional groups involved in metal ion adsorption and surface porosity.
Show more [+] Less [-]Local fruit wastes driven benthic microbial fuel cell: a sustainable approach to toxic metal removal and bioelectricity generation
2022
Yaqoob, Asim Ali | Guerrero–Barajas, Claudia | Ibrahim, Mohamad Nasir Mohamad | Omar, Khalid | Yaakop, Amira Suriaty
The present work focused on the utilization of three local wastes, i.e., rambutan (Nephelium lappaceum), langsat (Lansium parasiticum), and mango (Mangifera indica) wastes, as organic substrates in a benthic microbial fuel cell (BMFC) to reduce the cadmium and lead concentrations from synthetic water. Out of the three wastes, the mango waste promoted a maximum current density (87.71 mA/m²) along with 78% and 80% removal efficiencies for Cd²⁺ and Pb²⁺, respectively. The bacterial identification proved that Klebsiella pneumoniae, Enterobacter, and Citrobacter were responsible for metal removal and energy generation. In the present work, the BMFC mechanism, current challenges, and future recommendations are also enclosed.
Show more [+] Less [-]Persistence evaluation of fluopyram + tebuconazole residues on mango and pomegranate and their risk assessment
2022
Tripathy, Vandana | Sharma, Krishan Kumar | Mohapatra, Soudamini | Siddamallaiah, Lekha | Matadha, Nagapooja Yogendraiah | Patil, Chidanand Shiveshankar | Saindane, Yogesh Subhash | Deore, Bhaidas | Rao, Cherukuri Sreenivasa | Parmar, Kaushik D. | Litoriya, Nitesh S. | Shah, Paresh G. | Sharma, Khushbu
The persistence of combination formulation of fluopyram 200 + tebuconazole 200–400 SC was evaluated across different agro-climates in India for the management of fungal diseases in two commercially important fruit crops, mango and pomegranate. The residues were extracted using quick easy cheap effective rugged and safe (QuEChERS) method and quantification was done on liquid chromatography-tandem mass spectrometry (LC–MS/MS). The fungicide degradation followed 1st-order kinetics and the half-lives were 2.9–6.4 days for mango, and 3.5–7.4 days for pomegranate for both the fungicides. On the basis of Organisation for Economic Co-operation and Development (OECD) maximum residue limit (MRL) calculation, 1.0 mg kg⁻¹ MRL was obtained for fluopyram while for tebuconazole, it was 0.5 mg kg⁻¹ on mango, at the pre-harvest interval (PHI) of 5 days. For pomegranate, the respective MRLs were 1.0 mg kg⁻¹ and 0.7 mg kg⁻¹ at PHI of 7 days. The dietary risk assessment study indicated that % acceptable daily intake (% ADI) and % acute reference dose (% ARfD) were much lower than 100; thus, the application of fluopyram and tebuconazole on mango and pomegranate is unlikely to present public health concern.
Show more [+] Less [-]Review on solar dryers for drying fish, fruits, and vegetables
2022
Natarajan, Sendhil Kumar | Elangovan, Elavarasan | Elavarasan, Rajvikram Madurai | Balaraman, Anand | Sundaram, Senthilarasu
India is one of the highly developing countries in the world and it has the second-largest agricultural source of income, which covers 61% of the entire income of the country. The most valuable income group, by giving the appropriate training in this technology, will make their entire country to become one of the most highly developing counties in the world. In recent years, many developing, developed, and underdeveloped countries face shortages of fish, fruits, and vegetables due to natural disasters like earthquakes, tsunami, and any other unexpected events. Now the main issue of this paper is to preserve the food products from post-harvest to consumer-level, which cover 60% of losses due to the unavailability of preservative methods. This paper mainly focused on the conventional methods to advanced solar drying technologies for perseverating fish, fruits, and vegetables and also it discusses the technology used for drying the yield range of fish like Atheriniformes, Catfish, Chilwa, etc. Fruits like banana, mango, and papaya, and vegetables like bitter gourd, cabbage, and cocoa beans have been reviewed and also discussed some problems along with their solutions in concern with food products drying, thereby the selection of dryer for drying products will be made easy by this review article. On the whole, this investigation would help researchers in fish drying to choose the better drying methods for acquiring better results for particular fish, fruits, and vegetables that enable any entrepreneur to select the appropriate method reducing the cost and time.
Show more [+] Less [-]Persistence and dissipation study of azoxystrobin, buprofezin, dinocap and hexaconazole on mango (Mangifera indica L.)
2020
Mohapatra, Soudamini | Siddamallaiah, Lekha | Matadha, Nagapooja Yogendraiah | Gadigeppa, Shambulinga | Raja, Danish Poothotathil | Udupi, Veena Rao
Azoxystrobin, buprofezin, dinocap and hexaconazole are widely used in crop protection of mango from flowering to harvest. Residue assessment of these chemicals on mango fruits was done following treatments at the recommended and double doses as per good agricultural practices (GAP). Mango fruit and soil sample preparation was done by QuEChERS, and analysis was done using LC-MS/MS (liquid chromatography mass spectrometry). Using these techniques, the limit of detection (LOD) determined was 1.5 μg kg⁻¹ and limit of quantification (LOQ) was 0.005 mg kg⁻¹ for all analytes. The residue levels on mango initially were 0.265 and 0.55 mg kg⁻¹ for azoxystrobin, 0.63 and 0.974 mg kg⁻¹ for buprofezin, 0.635 and 0.98 mg kg⁻¹ for dinocap and 0.203 and 0.35 mg kg⁻¹ for hexaconazole from standard and double dose treatments, respectively. The dissipation rate of the pesticides on mango fruits was about the same except for azoxystrobin, which dissipated slowly compared with others. The half-life of degradation (DT₅₀) of azoxystrobin was 10.4–12.1 days; buprofezin, 5.8–8.5 days; dinocap, 5.4–6.2 days; and hexaconazole, 4.4–6.1 days. The pre-harvest interval (PHI) based on European Union (EU) MRL (maximum residue limit) requirements were 1 day for azoxystrobin, 15 and 26 days for buprofezin, 27 and 34 days for dinocap, and 19 and 30 days for hexaconazole. The results of this study can be used to produce mango fruits safe for consumption and to meet the regulatory requirements for export of mango fruits from India.
Show more [+] Less [-]Chromium (VI) remediation in aqueous solution by waste products (peel and seed) of mango (Mangifera indica L.) cultivars
2019
De Goes Sampaio, Caroline | Silva, Juliana Gaspar Alan E | De Brito, Edy Sousa | Becker, Helena | Trevisan, Maria Teresa Salles | Owen, Robert W.
The surface group characteristics of mango cultivar peels and seeds were evaluated by infrared spectra, PZC, and functional group composition. The adsorption/reduction of chromium (VI) in aqueous solutions was investigated by varying pH, contact time, initial Cr(VI) concentration, and adsorbent amount. The results show that both peel and seed powders of the mango cultivars showed significant adsorption/reduction capacity for Cr(VI) and that the desorption process obeys pseudo-second-order kinetics. Optimal adsorption occurred at pH 1.0, using a Cr(VI) concentration of 100 mg/L. On average, at pH 1.0, and a concentration of 3 g/L, the maximum adsorption/reduction capacity of Cr(VI) was 83% (peels 76%, seeds 90%). Of the mango powders tested, the most efficient were Tommy seed (100%) and Coite peel (98%) followed by Coite seed (96%) and Tommy peel powders (95%). The adsorption/reduction of Cr(VI) was complete (100%) by the mango seed, in comparison to the peel powders (97%) after 180 min. The data indicates that mango waste products, such as seed and peel powders, are both excellent candidates for the remediation of Cr(VI) from aqueous systems and due to the higher concentration of gallates and galloyl glucosides, the mango seed powders should be the powders of choice for future remediation projects.
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