► First nationwide data on metals in commercial fish from specific regions of the world. ► Greatest risk from different metal resided in different fish. ► Fish from these regions are within the ...safety levels. ► Useful to public health providers and state health officials to make guidance or standards.
Commercially important fresh (581) and frozen (292) marine fish samples of 10 species were collected from seafood factories and evaluated using AAS and ICP–OES. Metal levels significantly (p<0.05) varied within and between species. However, there were no significant correlations among metals. There were significant interspecific differences for all metals, and yellowfin tuna had the highest level of cadmium and mercury however, red seabream had maximum numbers above the standards. The metal accumulation significantly varied between bottom feeders of intermediately size locally caught fish. The mean cadmium level ranged from 0.0049 to 0.036mgkg−1 and 1.37% of the total samples exceeded the EU and FAO standards. Mean lead content varied between 0.029 and 0.196mgkg−1, few samples crossed the EU (2.63%) and FAO (1.6%) limits. Mean mercury level ranged from 0.015 to 0.101mgkg−1 and none of the samples exceeded the EU limit. Of the total samples analyzed red seabream (2.06%), yellowfin tuna (1.14%), emperor (0.34%), santer bream (0.22%), king fish (0.11%) and skipjack tuna (0.11%) samples crossed the EU limits. In general, fish from these regions are within the safety levels recommended by various organizations and do not pose a health risk in terms of human diet.
TEM image showed that MWCNTs are homogeneously decorated with Mn0.8Zn0.2Fe2O4 particles. The interaction seems to be sufficiently strong, as demonstrated by the absence of any free ferrite particles ...especially after prolonged sonication subsequent to TEM measurement. Display omitted
•Mn0.8Zn0.2Fe2O4 was prepared using spent Zn–C batteries through sucrose method.•MWCNTs/Mn0.8Zn0.2Fe2O4 nano-composite was prepared via same method.•The nano-composite was characterized and investigated to remove crystal violet dye.•After removal, the nano-composite can be easily separated using a normal magnet.•The optimum condition for the efficient removal was investigated and discussed.
In the present study, a simple, economic and environmentally friend method was utilized for the production of multi-walled carbon nanotubes (MWCNTs) decorated with Mn0.8Zn0.2Fe2O4 nanoparticles, synthesized via recycling process of Zn–C battery. The chemical composition and structure of the MWCNTs/Mn0.8Zn0.2Fe2O4 composite were confirmed by X-ray diffraction and Fourier transform infrared measurements. The morphology as well as the decoration process was characterized using transmission electron microscopy. The results showed that the MWCNTs are homogeneously decorated with cubic loosely agglomerated ferrite particles having mean crystallite size of 20nm. An appropriate decoration mechanism was suggested and discussed. The hysteresis measurements exhibited reasonable magnetic characteristics for the obtained composite which facilitate its separation from their dispersed solution using normal magnet. Surface area measurement indicates relatively large specific surface enhances its use in adsorption process. The adsorption capacity of the entire composite was investigated using crystal violet dye. The effect of composite mass, contact time, solution pH and solution temperature on the adsorption process was investigated. The adsorption process was found to follow a pseudo-second-order model. The calculated adsorption thermodynamic parameters (ΔG, ΔH and ΔS) suggested the spontaneity of the thermodynamically favorable adsorption process.
Pavement rehabilitation and reconstruction generates large quantities of reclaimed asphalt pavement (RAP) aggregate, and recycling into new asphalt paving mixtures is the predominant application. RAP ...acceptance in road bases and subbases has been limited, because of the lack of laboratory and field performance data. In the Sultanate of Oman, recycling of pavement materials is not practiced. A previous study conducted at Sultan Qaboos Univ. indicated that RAP-virgin aggregate mixtures could be utilized in the subbase layer rather than in the base course. This paper presents the results of a laboratory evaluation of cement stabilized RAP and RAP-virgin aggregate blends as base materials. Compaction and unconfined compressive strength tests were conducted on the following RAP/virgin aggregate mixtures: 100/0, 90/10, 80/20, 70/30, and 0/100%. Samples were prepared using 0, 3, 5, and 7% Type I portland cement and were cured for 3, 7, and 28 days in plastic bags at room temperature. A pavement design analysis of using various cement stabilized RAP-virgin aggregate mixtures as base materials was also undertaken. Results indicate that the optimum moisture content, maximum dry density, and strength of RAP will generally increase with the addition of virgin aggregate and cement. Longer curing periods will yield higher strength results. The ability of RAP aggregate to function as a structural component of the pavement is more pronounced when it is stabilized with cement rather than when blending with only virgin aggregate. A 100% RAP aggregate should not be recommended for use as a base material unless stabilized with cement. Cement stabilized RAP-virgin aggregate mixtures seem to be a viable alternative to dense-graded aggregate used in road base construction.
Mn1−xZnxFe2O4 (x=0.2–0.8) nano-crystals, synthesized from recycling of Zn–C batteries, were successfully self-assembled alongside multi-walled carbon nanotubes (MWCNTs) via an environmentally friend ...sucrose auto-combustion method. The effect of Zn-content on structural and magnetic properties were investigated and discussed. XRD revealed the formation of single-phase ferrites. DTA–TG experiment showed that the auto-combustion reaction finished at about 350°C. TEM exhibited that the MWCNTs are well decorated with ferrite particles. Hysteresis loop measurements revealed ferromagnetic behavior, with saturation magnetization decrease by the addition of MWCNTs or increasing Zn-Content. The kinetics of methylene blue dye (MB) removal using MWCNTs/Mn0.8Zn0.2Fe2O nano-composite was investigated and discussed.
TEM image of MWCNTs/Mn0.8Zn0.2Fe2O4 nano-composite showed that the MWCNTs were completely decorated with magnetic nanoparticles. The decoration passed through nucleation and growth processes in which nucleation of ferrite nanoparticles first takes place on the surface of MWCNTs followed by a subsequent growth of these nuclei.
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•Mn-Zn-ferrites were obtained via recycling process of spent Zn-C batteries.•Mn1−xZnxFe2O4/MWCNTS nano-composites were synthesized via sucrose combustion route.•Zn-substitution effect on structural and magnetic properties was investigated.•MWCNTs/Mn0.8Zn0.2Fe2O4 was investigated to remove MB dye from aqueous media.
Cyclone Gonu storm surge in Oman Fritz, Hermann M.; Blount, Christopher D.; Albusaidi, Fawzi B. ...
Estuarine, coastal and shelf science,
2010, 2010-1-00, 20100101, Letnik:
86, Številka:
1
Journal Article
Recenzirano
Super Cyclone Gonu is the strongest tropical cyclone on record in the Arabian Sea. Gonu caused coastal damage due to storm surge and storm wave impact as well as wadi flooding. High water marks, ...overland flow depths, and inundation distances were measured in the coastal flood zones along the Gulf of Oman from 1 to 4 August 2007. The high water marks peaked at Ras al-Hadd at the eastern tip of Oman exceeding 5
m. The storm surge of Gonu is modeled using the Advanced Circulation Model (ADCIRC). The multi-hazard aspect is analyzed by comparing observations from Cyclone Gonu with the 2004 Indian Ocean Tsunami.
Trigger finger is uncommon among children and often caused by various lesions. We report a 5-year old girl who presented with chronic painless triggering of the right ring finger and normal X-ray. ...She underwent exploration of the finger flexor tendons and release of the A1 pulley. Lack of obvious pathology dictated further wound exploration which revealed a hidden osteochondroma of the proximal phalanx. We believe that adequate surgical wound exposure is necessary if no obvious cause of triggering could be seen in order to rule out an atypical osteochondroma even in the presence of normal X-rays.
In the present study, Mn0.8Zn0.2Fe2O4 nanoparticles, synthesized from spent Zn–C batteries extract, were successfully used for decoration of multi-walled carbon nanotubes (MWCNTs). This ...MWCNTs/Mn0.8Zn0.2Fe2O4 magnetic nano-composites were prepared by the addition of MWCNTs during the preparation of the entire ferrite using sucrose combustion method. The effect of MWCNTs content (0–70%) on the structural, morphological and magnetic properties of entire ferrite was investigated and discussed. The results showed that high purity Mn0.8Zn0.2Fe2O4 nano-crystallites were completely decorated on the sidewalls of the MWCNTs up to 30% content and the decoration behavior, shape and density are dependent on the composition. The saturation magnetization was observed to decrease with increasing MWCNTs content while coercivity showed a particle size dependent behavior. The composition with 70% MWCNTs was examined as adsorbent for methylene blue dye (MB) from aqueous media based on its relatively high surface area and the capability of removing the nano-composite after adsorption process using normal magnet. The nano-composite showed a very high adsorption capacity and the kinetic as well as the thermodynamics of adsorption/removal process were investigated and discussed. Repeated testing showed the applicability of the nano-composite for the removal of MB from aqueous solution frequently with acceptable efficiencies.
•Mn0.8Zn0.2Fe2O4 was prepared using spent Zn–C batteries through sucrose method.•MWCNTs/Mn0.8Zn0.2Fe2O4 nano-composite was prepared via the same method.•Compositional effect (0–70% MWCNTs) on structural and magnetic properties was studied.•Nano-composite was investigated to remove methylene blue dye from the aqueous media.•The nano-composite is efficient for the removal of MB from aqueous solution frequently.
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