The present work represents a comparative study for removing acid green dye 50 by anodic oxidation and electrocoagulation using a new batch self gas stirred electrochemical cell. The effect of ...operating parameters such as current density, initial dye concentration, NaCl concentration and pH on the efficiency of colour removal has been examined. The chemical oxygen demand (COD) reduction under suitable operating conditions was also calculated and found to be reduced by 68% and 87% in case of electrochemical oxidation and electrocoagulation methods, respectively. The results indicate that electrocoagulation is more economic than anodic oxidation, energy consumption ranged from 2.8 to 12.8
kWh/kg dye removed in case of electrocoagulation while in case of anodic oxidation it ranged from 3.31 to 16.97
kWh/kg dye removed. Although the mechanisms of electrocoagulation and anodic oxidation are different, results show that the first-order rate equation provides the best correlation for the decolourization rate of acid green 50 by the two methods.
Background
The main object of the present study is the industrial wastewater effluent treatment resulting from a solar cell manufacturing process, which is a Joint Egyptian Chinese Renewable Energy ...laboratory, in Sohag Governorate. Fluoric and hydrochloric acids are the main pollutants causing a pH of 1 to 3. The effluent is neutralized by the addition of both potassium hydroxide and calcium hydroxide to permit the precipitation of the resulting sparingly soluble calcium fluoride. The chlorides are partially precipitated as calcium chloride, and the further addition of hydrated aluminum sulfate is used to precipitate the remaining extra chloride as an insoluble complex to reach the allowable chloride concentration in the treated effluent. Set of experiments at bench and pilot scales were run to achieve the optimum conditions for defluorination and dichlorination taking into consideration not exceeding the allowable ranges of pollutants as soluble salts in the final effluent.
Results
Experimental results showed that the performance of a pilot scale was satisfactory in fluorides, chlorides, and dissolved solids by 97.64, 78.85, and 79.4% removal, respectively. Based on these results a full-scale industrial treatment unit was designed for construction and operation as a treatment unit for industrial wastewater contaminated with fluorides as main pollutant.
Conclusions
The recommended treatment procedure succeeded in the removal of fluorides and chlorides as main contaminants in the effluent which permit the use of treated water in the irrigation of non-edible plants, according to Egyptian Code No. (501/2015).
Bagasse pith, which is the main waste from sugarcane industry in Egypt, has been used as a raw material for the preparation of different activated carbons. Activated carbons were prepared from ...bagasse pith by chemical activation with 28% H
3PO
4 (AC1), 50% ZnCl
2 (AC2) followed by pyrolysis at 600°C and by physical activation at 600°C in absence of air (AC3). Different activated carbons have been used for the removal of reactive orange (RO) dye from aqueous solutions. Batch adsorption experiments were performed as a function of initial dye concentration, contact time, adsorbent dose and pH. Adsorption data were modeled using the Langmuir and Freundlich adsorption isotherms. Adsorption kinetic data were tested using pseudo-first-order, pseudo-second-order and intraparticle diffusion models. Kinetic studies showed that the adsorption followed pseudo-second-order reaction with regard to the intraparticle diffusion rate.
► The reactor used in the study was a rotating cylinder packed with cation exchange resin. ► The experimental data were analyzed using different isotherms. ► The equilibrium data fit well in the ...Langmuir isotherm. ► The experimental data were analyzed using four sorption kinetic models. ► Results show that the Elovich equation provides the best correlation for the biosorption process.
The present study is concerned with the mass transfer and kinetics study of zinc ions removal from aqueous solution using a cation exchange resin packed in a rotating cylindrical basket reactor. The effect of various experimental parameters on the rate of zinc ion removal, such as initial zinc ion concentration, packed bed rotation speed and temperature has been investigated. In addition to find a suitable equilibrium isotherm and kinetic model for the zinc ion removal in a batch reactor. The experimental isotherm data were analyzed using the Langmuir, Freundlich and D–R equations. The equilibrium data fit well in the Langmuir isotherm. The experimental data were analyzed using four sorption kinetic models, pseudo-first and second-order equations, the Elovich and the intraparticle diffusion model equation, to determine the best fit equation for the biosorption of zinc ions onto purolite C-100 MH resin. Results show that the Elovich equation provides the best correlation for the biosorption process.
Cellulose nanocrystal (CNC) is a unique nanomaterial that have received considerable attention due to its good individual mechanical properties and was proven as a good reinforcing filler to various ...polymer matrix. Thermoplastic polyurethane (TPU), have been widely used for lots of application like automobile, aerospace and medical industries. However, because of its chemical structure, TPU have significant deficiencies like low tensile strength as working with high force application. Thus, CNC has been used to overcome this limitation. This research was conducted to investigate the rheological properties of CNC in TPU and water matrix. CNC were obtained from microcrystalline cellulose (MCC) via sulphuric (CNC-S) and phosphoric (CNC-P) acid hydrolysis. CNCs (1 wt%, 2 wt% and 5 wt%) were dispersed in TPU and water matrix. CNC produced and its suspension were undergoing Field Emission Scanning Electron Microscopy (FESEM) and rheological test to identify the morphology and rheological behaviour respectively. CNC-S obtained has diameter of 17 ± 4 nm and length of 225 ± 100 nm, while CNC-P has diameter of 20 ± 5 nm and length of 231 ± 127 nm. The aspect ratio for CNC-P and CNC-S are 11 and 13 respectively. The rheology properties like viscosity of CNC-S were compared to CNC-P in both matrices. The viscosity of the TPU/CNC-S and TPU/CNC-P solutions recorded highest value at 5 wt% of CNC loading similar result was recorded as well in water matrix. In TPU, at shear rate of 0.1 s−1, the viscosity of TPU/CNC-S is 192.1 Pa.S and TPU/CNC-P solution is 173.4 Pa.S. Meanwhile, in aqueous suspension, at shear rate of 0.1 s−1, the viscosity of CNC-P recorded higher value than CNC-S suspension at 772,800 Pa.S and 1045 Pa.S respectively. This has proven that type of acid in CNC production and suspension matrix influence the rheological properties of CNC suspension.
In this study anodic oxidation of Cr
2
(SO
4
)
3
was carried out in an air-sparged divided parallel plate cell. Variables studied were current density, Cr
2
(SO
4
)
3
concentration, and superficial ...air velocity. The rate constant of Cr
2
(SO
4
)
3
oxidation was found to increase with increasing current density and Cr
2
(SO
4
)
3
concentration. The effect of air sparging was found to depend on Cr
2
(SO
4
)
3
concentrations, at high Cr
2
(SO
4
)
3
concentration (> 0.1 M) air sparging does not affect the rate constant of the reaction denoting that the reaction is charge transfer controlled. As Cr
2
(SO
4
)
3
concentration decreases below 0.1 M the reaction becomes under mixed diffusion and chemical control and the rate constant increases with increasing air superficial velocity, the lower Cr
2
(SO
4
)
3
concentration the higher the contribution of diffusion to the reaction rate. The current efficiency of the process ranged from 20 to 85% depending on current density and Cr
2
(SO
4
)
3
concentration. Electrical energy consumption which ranged from 1.8 to 14.4 kW h/kg of Cr
6+
was found to increase with increasing current density and decreases with increasing Cr
2
(SO
4
)
3
concentration. Air sparging was found to decrease electrical energy consumption in the case of dilute solutions << 0.1 M Cr
2
(SO
4
)
3
.
RECONSTRUCTION OF 3D ACCIDENT SCENE FROM MULTIROTOR UAV PLATFORM Mat Amin, M. A.; Abdullah, S.; Abdul Mukti, S. N. ...
International archives of the photogrammetry, remote sensing and spatial information sciences.,
08/2020, Letnik:
XLIII-B2-2020
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Traffic accidents are one of the major causes of fatality in developing countries. The aim of the study is to reconstruct accident scenes by using UAV photogrammetry. The methodology of this study is ...organised into four main phases which consist of preliminary work, flight planning, 3D model processing and analysis of the results. The 3D model was successfully generated by using Point of Interest (POI) flight planning. The 3D model showed that the results of the process produced good 3D texture where the two vehicles had good shapes and could be seen clearly from an oblique view. In addition, the effect of the tyres on the road could also be seen clearly and had good shape which were generated accurately. The accuracy values obtained from the POI technique and waypoint technique were 0.059m and 0.043m, respectively. Due to the availability of UAVs in the market at reasonable costs, photogrammetry offers the best alternative technique to other methods that have been used to reconstruct the accident scene.
Background: Exposure to chronic stress induces oxidative damage which alters the dynamic balance between antioxidant and pro-oxidant activities in the brain. Tualang honey (TH) is a Malaysian wild ...multifloral honey which has been shown to contain high amount antioxidants. DHA-rich fish oil is a form of omega-3 fatty acids found in fish which also possesses some antioxidant activity. This study aimed to evaluate anti-stress activity of DHA-rich fish oil, TH and their combination on several parameters of oxidative stress in chronic stress rat model. Methods: Fifty male Sprague Dawley rats were divided into (i) control, (ii) stress-exposed, (iii) stress-exposed and treated with TH (1 g/kg body weight twice daily), (iv) stress-exposed and treated with DHA-rich fish oil (450 mg/kg body weight twice daily), and (v) stress-exposed and treated with a combination of TH and DHA-rich fish oil. The chronic stress regimen consisted of a combination of restraint stress and a swim stress test for 28 days. Results: DHA-rich fish oil and TH significantly (p ＜ 0.05) supressed stress-induced elevation of serum corticosterone and lipid peroxidation, and caused a significant increase in total antioxidant capacity. For glutathione status, only TH significantly reduced stress-induced elevation of oxidised glutathione (GSSG) and normalised GSH/GSSG ratio. Conclusion: Both DHA-rich fish oil and TH have protective effects against brain oxidative stress but consuming these substances together does not seem to provide an additional benefit compared to consuming them separately.
Shelf life of biocomposite can be monitored by many preservation methods such as drying of biocomposite. Upon drying, water molecule will be removed due to evaporation to surrounding and effect the ...biocomposite quality, chemical and mechanical properties. Over drying process will lead to the reduction of chemical and mechanical properties of biocomposite. In this work, determination of the best drying time for carrageenan biocomposite hard capsule was performed and compared with commercial hard capsules which are gelatine (GHC) and hydroxypropyl methylcellulose (HPMC). Carrageenan was mixed with crosslinker, cellulose nanocrystal (CNC) and toughening agent at various drying time. The colloid solution was dipped using size "1" dipping bar and dried at 60 0C for various drying time from 40 to 60 minutes in an oven. The carrageenan hard capsule (CHC) was analysed for weight variation, functional group and capsule hardness test. The result showed that increasing the drying time decreased the properties of the CHC. The CHC had higher hydroxyl group absorbance area in comparison to GHC and HPMC. Meanwhile, the GHC had the highest hardness load followed by HPMC and CHC. Material hardening occurred in CHC biocomposite upon increasing drying time thus lead to material shrinkage and water loss from the sample.
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