The performance of activated carbon/NiFe2O4 magnetic composite to retain heavy metal ions from aqueous solution

A novel magnetic activated carbon composite(AC/NiF) was synthesized by a precipitation method and applied in retention of Cu(Ⅱ),and Zn(Ⅱ) ions from aqueous solutions.The impact of different sorption parameters such as:equilibration time,solution pH value,competing cations and ionic strength on the amount sorbed of Cu(Ⅱ),and Zn(Ⅱ) was clarified.Results illustrated that the magnetic composite had retention ability towards both metal ions significantly higher than that of activated carbon(AC).The magnetic composite exhibited an affinity to adsorb Cu(Ⅱ) higher than Zn(Ⅱ) ions.The maximum sorption capacities(Q_(max)) of the applied magnetic composite(AC/NiF)towards Cu(Ⅱ) and Zn(Ⅱ) were 105.8 and 75.1 mg·g~(-1),respectively.Retention of Cu(Ⅱ) and Zn(Ⅱ) was proposed to be achieved though an ion exchange and surface adsorption in neutral conditions,while precipitation was believed to be the relevant mechanism in their removal from basic solutions.The kinetic studies showed that sorption process followed the kinetics of pseudo-second-order reactions with rate constant of 3 × 10~(-3) and 2 × 10~(-3) min~(-1)for sorption of Cu(Ⅱ) and Zn(Ⅱ) onto AC/NiF composite.Removal of Cu(Ⅱ) slightly decreased with increasing the ionic strength of aqueous solution,using NaCl as a background electrolyte.In contrast,presence of Mn(Ⅱ),Mg(Ⅱ)and Co(Ⅱ) in reaction solutions highly depressed the sorption of Cu(Ⅱ) and Zn(Ⅱ) with a competing efficiency followed the order:Mg(Ⅱ) Mn(Ⅱ) Co(Ⅱ).The magnetic composite was rapidly recovered from aqueous solution by an external magnetic field,and effectively regenerated using 0.1 mol L~(-1) HCl and 0.1 mol L~(-1) FeCl_3 as eluents.Sorption of Cu(Ⅱ) and Zn(Ⅱ) onto the surface of AC/NiF composite occurred via a spontaneous reaction.And thermodynamically favorable process had ΔH~o values of 30.9 kJ·mol~(-1) and 19.7 kJ·mol~(-1),respectively.The results confirm that the magnetic composite can be viewed as a promising novel composite opens new opportunities for the attainment of required adsorption and operative magnetic separation.     

Breast cancer diagnosis system based on wavelet analysis and fuzzy-neural

The high incidence of breast cancer in women has increased significantly in the recent years. The most familiar breast tumors types are mass and microcalcification. Mammograms—breast X-ray—are considered the most reliable method in early detection of breast cancer. Computer-aided diagnosis system can be very helpful for radiologist in detection and diagnosing abnormalities earlier and faster than traditional screening programs. Several techniques can be used to accomplish this task. In this paper, two techniques are proposed based on wavelet analysis and fuzzy-neural approaches. These techniques are mammography classifier based on globally processed image and mammography classifier based on locally processed image (region of interest). The system is classified normal from abnormal, mass for microcalcification and abnormal severity (benign or malignant). The evaluation of the system is carried out on Mammography Image Analysis Society (MIAS) dataset. The accuracy achieved is satisfied.     

Precursor Effects of the Giant Magnetoresistance Regime in Calcium Doped Manganites

Inelastic neutron scattering has been used on La_1–x Ca _x MnO₃ compound 0with 0x0.10 to describe their dynamic magnetic properties. In addition to super exchange coupling between Mn ions (ferromagnetic (F) in (a, b) planes and antiferromagnetic (AF) along the c direction), a new type of F coupling is found, induced by mobile carriers between magnetic Mn ions. It is revealed by well-defined propagative spin wave modes with a gap and a nearly isotropic dispersion law: =₀+Dq ². The q-evolution of the instantaneous spin pair correlations remind F inhomogeneities embedded in the mean AF lattice. These results could be understood in a frame of an electronic phase separation.     

Materials for multifunctional balloon catheters with capabilities in cardiac electrophysiological mapping and ablation therapy

Developing advanced surgical tools for minimally invasive procedures represents an activity of central importance to improving human health. A key challenge is in establishing biocompatible interfaces between the classes of semiconductor device and sensor technologies that might be most useful in this context and the soft, curvilinear surfaces of the body. This paper describes a solution based on materials that integrate directly with the thin elastic membranes of otherwise conventional balloon catheters, to provide diverse, multimodal functionality suitable for clinical use. As examples, we present sensors for measuring temperature, flow, tactile, optical and electrophysiological data, together with radiofrequency electrodes for controlled, local ablation of tissue. Use of such 'instrumented' balloon catheters in live animal models illustrates their operation, as well as their specific utility in cardiac ablation therapy. The same concepts can be applied to other substrates of interest, such as surgical gloves.     

Enhancement of mechanical properties of high modulus polypropylene grade for multilayer sewage pipes applications

Advances in technology have provided fresh generations of stiff polypropylene block copolymers for gravity sewerage applications. The aim of this study is to further enhance the stiffness of these materials through the incorporation of inorganic fillers. In this study, three talc filled PP and one glass fiber filled PP composites were characterized in order to be used as a middle layer in a three-layer sewage pipe. The obtained results showed an increase of approximately more than 100% and 250% in tensile and flexural moduli by the use of 30%–50 wt% talc-filled PP and 30 wt.% glass fiber-filled PP, respectively. This high increase in the rigidity of the material would allow manufacturing pipes with improving ring stiffness. Composites filled with 30 wt% talc or glass fiber showed good filler-matrix interaction and good filler distribution and dispersion. However, reduced filler-matrix interaction was observed in the case of the composite filled with 50 wt% talc. In addition, the use of Differential Scanning Calorimetry analysis revealed that the addition of fillers enhanced the crystallization temperature of the polypropylene matrix. Furthermore, Thermogravimetric Analysis showed that the high modulus PP grade retained its thermal stability in the various composites.     

Influence of gamma-irradiation and maize lipids on the production of aflatoxin B1 by Aspergillus flavus

The effect of gamma-irradiation and maize lipids on aflatoxin B1 production by Aspergillus flavus artificially inoculated into sterilized maize at reduced water activity (aw 0.84) was investigated. By increasing the irradiation doses the total viable population of A. flavus decreased and the fungus was completely inhibited at 3.0 kGy. The amounts of aflatoxin B1 were enhanced at irradiation dose levels 1.0 and 1.5 kGy in both full-fat maize (FM) and defatted maize (DM) media and no aflatoxin B1 production at 3.0 kGy gamma-irradiation over 45 days of storage was observed. The level in free lipids of FM decreased gradually, whereas free fatty acid values and fungal lipase activity increased markedly by increasing the storage periods. The free fatty acid values decreased by increasing the irradiation dose levels and there was a significant enhancement of fungal lipase activity at doses of 1.0 and 1.50 kGy. The ability of A. flavus to grow at aw 0.84 and produce aflatoxin B1 is related to the lipid composition of maize. The enhancement of aflatoxin B1 at low doses was correlated to the enhancement of fungal lipase activity.     

Investigation into the multi-stage ring rolling of aluminium bicycle wheel rims

A method of producing bicycle wheel rims by expanding small diameter ring blanks in a ring rolling mill offers potential advantages over existing methods of rim production, which involve the circling and jointing of lengths of extruded section. The paper describes feasibility studies of the ring rolling method, the work having been sponsored by a cycle manufacturer. The required rim profile could not be formed in one rolling stage, from a simple form of ring blank, and a multi-stage rolling process was developed. The design of the forming rolls is described and problems encountered in achieving sound products of the required accuracy are discussed.     

Experimental investigation on the hysteresis behavior of the wire rope isolators

Vibration isolation has been widely applied to filter the external excitation energy and impact forces in building structures and equipment. Wire rope isolator (WRI), a kind of isolator for vibration and shock isolation, shows a better performance in attenuating these forces. WRIs are able to deviate these external forces through their mechanical configuration and high-energy dissipative capabilities. The application of WRI demands knowledge of its behavior and the relation between various geometrical properties and input force. The present work investigates the influence of geometrical parameters, such as wire rope diameter, number of coils, and displacement amplitude on the hysteresis behavior of WRI under quasi-static loading in both vertical and horizontal directions. The hysteresis behavior of different WRIs was evaluated using the calculated parameters from hysteresis force-displacement curves: energy loss ratio (ELR), and effective stiffness. The study indicates that the geometric properties significantly influence the effective stiffness than the energy loss ratio. It is observed that, increased displacement amplitude results in decreased ELR and hence damping capabilities. The study also confirms that the wire rope isolator possesses a good ability in damping through its stiffness and high-energy dissipation capability.     

Convalescent-plasma-transfusion intelligent framework for rescuing COVID-19 patients across centralised/decentralised telemedicine hospitals based on AHP-group TOPSIS and matching component

As coronavirus disease 2019 (COVID-19) spreads across the world, the transfusion of efficient convalescent plasma (CP) to the most critical patients can be the primary approach to preventing the virus spread and treating the disease, and this strategy is considered as an intelligent computing concern. In providing an automated intelligent computing solution to select the appropriate CP for the most critical patients with COVID-19, two challenges aspects are bound to be faced: (1) distributed hospital management aspects (including scalability and management issues for prioritising COVID-19 patients and donors simultaneously), and (2) technical aspects (including the lack of COVID-19 dataset availability of patients and donors and an accurate matching process amongst them considering all blood types). Based on previous reports, no study has provided a solution for CP-transfusion-rescue intelligent framework during this pandemic that has addressed said challenges and issues. This study aimed to propose a novel CP-transfusion intelligent framework for rescuing COVID-19 patients across centralised/decentralised telemedicine hospitals based on the matching component process to provide an efficient CP from eligible donors to the most critical patients using multicriteria decision-making (MCDM) methods. A dataset, including COVID-19 patients/donors that have met the important criteria in the virology field, must be augmented to improve the developed framework. Four consecutive phases conclude the methodology. In the first phase, a new COVID-19 dataset is generated on the basis of medical-reference ranges by specialised experts in the virology field. The simulation data are classified into 80 patients and 80 donors on the basis of the five biomarker criteria with four blood types (i.e., A, B, AB, and O) and produced for COVID-19 case study. In the second phase, the identification scenario of patient/donor distributions across four centralised/decentralised telemedicine hospitals is identified ‘as a proof of concept’. In the third phase, three stages are conducted to develop a CP-transfusion-rescue framework. In the first stage, two decision matrices are adopted and developed on the basis of the five ‘serological/protein biomarker’ criteria for the prioritisation of patient/donor lists. In the second stage, MCDM techniques are analysed to adopt individual and group decision making based on integrated AHP-TOPSIS as suitable methods. In the third stage, the intelligent matching components amongst patients/donors are developed on the basis of four distinct rules. In the final phase, the guideline of the objective validation steps is reported. The intelligent framework implies the benefits and strength weights of biomarker criteria to the priority configuration results and can obtain efficient CPs for the most critical patients. The execution of matching components possesses the scalability and balancing presentation within centralised/decentralised hospitals. The objective validation results indicate that the ranking is valid.