Removal of heavy metals by adsorption on Pleurotus ostreatus

The present study explores the adsorption potential of Pleurotus ostreatus (a macro-fungus) to remove copper, nickel, zinc and chromium from water all together. Different operational parameters such as the effect of pH, biomass dose, equilibrium time, stirring intensity, temperature and initial metal ion concentrations were studied. Maximum adsorption of Ni(II), Cu(II) and Zn(II) took place in the pH range 4.5-5.0, whereas for Cr(VI) ion, best results were achieved at pH 2.5. Nearly 150 min are required to gain sorption equilibrium. Temperature has no significant effect on biosorption in the range of 20-45 °C. The maximum biosorption capacity of fungus was 8.06, 20.40, 3.22 and 10.75 mg g⁻¹ for Cu(II), Ni(II), Zn(II) and Cr(VI) in that order. FTIR analysis pointed out the involvement of amine (-NH₂) and carboxylic (-COOH) groups in the adsorption process. Simple and adjusted Langmuir and Freundlich isotherm models were used to explain the sorption phenomenon. For real effluents of electroplating, biosorption capacities were 2.73, 8.45, 0.88 and 4.45 mg g⁻¹ for Cu(II), Ni(II), Zn(II) and Cr(VI) ions, respectively. Moreover, used P. ostreatus was recycled repeatedly and used many times to evaluate the adsorption efficacy on reuse, but findings pointed out that capacity decreased, to some extent, on recycling.     

Exact solution for thermoelastoplastic behavior of thick-walled functionally graded sphere under combined pressure and temperature gradient loading

Considering the combined uniform pressure and thermal loading condition, a closed form analytical thermoelastoplastic solution for thick-walled spheres made of functionally graded materials (FGMs) is presented in this article. Taking into account three different scenarios for the onset of yielding, the formulas to determine stress field in both elastic and plastic zones of FG sphere are generated and the radius of the plastic zone is obtained for combined loading. It is shown that the effective stress in the sphere subjected to combined loading decreases significantly when the FG materials are used. Moreover, the FG sphere is simulated entirely using ABAQUS/Explicit software. Based on the good agreement between the results from present theoretical analysis and those from finite element simulation, the accuracy of the present analysis is verified.     

A highly sensitive method for simultaneous determination of ultra trace levels of copper and cadmium in food and water samples with luminol as a chelating agent by adsorptive stripping voltammetry

In the present study a selective method is presented for the simultaneous determination of copper and cadmium in food samples by adsorptive stripping voltammetry. In preliminary studies, it has been proven that the copper and cadmium react with 3-aminophthalhydrazide (luminol), giving rise to the formation of these complexes. These complexes have adsorptive characteristics on hanging mercury drop electrode (HMDE) and can be reduced in a reduction step. In this study the optimum reaction parameters and conditions studies are investigated. The calibration graphs were linear in the concentration range of 0.5–105.0 and 0.8–70.0 ng/ml for copper and cadmium, respectively. The limit of detection of the method was 0.04 ng/ml for Cu²⁺ and 0.02 ng/ml for Cd²⁺. The interference of some common ions was studied and it was concluded that application of this method for the determination of copper (II) and cadmium in food and water samples led to satisfactory results.     

Quantification of oxytocin residues in dairy milk from Sindh,Pakistan

In this study, a total of 84 milk samples (60 nonbranded and 24 branded) were analysed for occurrence of oxytocin (OT) residues by ELISA. OT level was detected in the range of 39.29–456.55 pg mL^?1 with mean value of 138.53 ng L^?1. In branded milk samples, OT residues were minimal as compared to nonbranded milk samples. Nonbranded milk samples had higher prevalence of OT residues; 16.67% had OT level in the range of ≤500 ng L^?1. The average daily intake of OT was found 0.087 μg day^?1 per person. It was concluded that the OT concentration was relatively higher in samples obtained from dairy farm, dairy shop and milk man than that in ultra‐high temperature (UHT) and powder milk samples. In addition, there are no reports subjected to standardising a permissible OT level in dairy milk category, although OT is considered detrimental to both human and animal life.     

A Combo Smart Model of Blockchain with the Internet of Things (IoT) for the Transformation of Agriculture Sector

Wireless Personal Communications - Nowadays traditional techniques of living and earning are being transformed to modern smart technologies, taking their inspiration from the emerging trends....     

Towards sensor array materials: can failure be delayed?

Further to prior development in enhancing structural health using smart materials, an innovative class of materials characterized by the ability to feel senses like humans, i.e. ‘nervous materials’, is discussed. Designed at all scales, these materials will enhance personnel and public safety, and secure greater reliability of products. Materials may fail suddenly, but any system wishes that failure is known in good time and delayed until safe conditions are reached. Nervous materials are expected to be the solution to this statement. This new class of materials is based on the novel concept of materials capable of feeling multiple structural and external stimuli, e.g. stress, force, pressure and temperature, while feeding information back to a controller for appropriate real-time action. The strain–stress state is developed in real time with the identified and characterized source of stimulus, with optimized time response to retrieve initial specified conditions, e.g. shape and strength. Sensors are volumetrically embedded and distributed, emulating the human nervous system. Immediate applications are in aircraft, cars, nuclear energy and robotics. Such materials will reduce maintenance costs, detect initial failures and delay them with self-healing. This article reviews the common aspects and challenges surrounding this new class of materials with types of sensors to be embedded seamlessly or inherently, including appropriate embedding manufacturing techniques with modeling and simulation methods.     

CFRP Prestressed High-Strength Concrete Prisms Subjected to Direct Tension

This paper describes the behavior of carbon fiber-reinforced polymer (CFRP) prestressed high-strength concrete prisms under direct tension. Seven prestressed concrete prisms with different levels of prestressing were cast and tested. Prisms were 50×50?mm in cross section and their lengths varied between 1,400 and 2,000?mm. Concrete compressive strength was as high as 147?MPa. Tension stiffening, crack width, and crack spacing in prisms were investigated. Concrete properties, such as the stress–strain relationship under direct tension and bond strength, were also determined. Test results revealed that tension stiffening in CFRP prestressed high-strength concrete is significant when higher concrete strength and higher prestressing level are applied. Tension stiffening factors are proposed based on the postcracking behavior of concrete. Experimental results also showed that increasing the prestressing level increases the amount of tension stiffening and reduces the number of cracks, which delays their appearance. However, cracks widened at a faster rate in the prisms with higher prestressing levels. Experimental results were compared with Comite Euro-International du Beton and American Concrete Institute proposed equations. Modifications were suggested for the above-mentioned equations to account for use of CFRP bars in prestressed sections.     

A noniterative greedy algorithm for multiframe point correspondence

This work presents a framework for finding point correspondences in monocular image sequences over multiple frames. The general problem of multiframe point correspondence is NP-hard for three or more frames. A polynomial time algorithm for a restriction of this problem is presented and is used as the basis of the proposed greedy algorithm for the general problem. The greedy nature of the proposed algorithm allows it to be used in real-time systems for tracking and surveillance, etc. In addition, the proposed algorithm deals with the problems of occlusion, missed detections, and false positives by using a single noniterative greedy optimization scheme and, hence, reduces the complexity of the overall algorithm as compared to most existing approaches where multiple heuristics are used for the same purpose. While most greedy algorithms for point tracking do not allow the entry and exit of the points from the scene, this is not a limitation for the proposed algorithm. Experiments with real and synthetic data over a wide range of scenarios and system parameters are presented to validate the claims about the performance of the proposed algorithm.