Toxic metal ion removal by terpolymer ion-exchanger from aqueous environments: synthesis,thermal degradation,batch separation,kinetic and isotherm studies

A novel chelating resin was synthesized and characterized by elemental, physico-chemical, GPC, NMR, and SEM analyses. Batch separation was adopted to study the recovery of selected metal ions with respect to the pH, time, concentrations, and electrolytes. From the results, it was observed that the order of the rate of metal ion uptake by the resin was Fe³⁺ > Cu²⁺ > Zn²⁺ > Ni²⁺ > Co²⁺ > Pb²⁺ ions. The adsorption kinetics follows first order, and isotherm models were also found to fit each other. The resin showed three-step thermal degradation, and its kinetic and thermodynamic parameters were also evaluated.     

Design and development of an efficient fluid mixing for 3D printed lab-on-a-chip

Microsystem Technologies - In this paper, we present elaborate study of design parameters of hybrid microfluidic mixer through numerical approach using finite element method and experimental...     

Optimized Schwarz method without overlap for the gravitational potential equation on cluster of graphics processing unit

Many engineering and scientific problems need to solve boundary value problems for partial differential equations or systems of them. For most cases, to obtain the solution with desired precision and in acceptable time, the only practical way is to harness the power of parallel processing. In this paper, we present some effective applications of parallel processing based on hybrid CPU/GPU domain decomposition method. Within the family of domain decomposition methods, the so-called optimized Schwarz methods have proven to have good convergence behaviour compared to classical Schwarz methods. The price for this feature is the need to transfer more physical information between subdomain interfaces. For solving large systems of linear algebraic equations resulting from the finite element discretization of the subproblem for each subdomain, Krylov method is often a good choice. Since the overall efficiency of such methods depends on effective calculation of sparse matrix–vector product, approaches that use graphics processing unit (GPU) instead of central processing unit (CPU) for such task look very promising. In this paper, we discuss effective implementation of algebraic operations for iterative Krylov methods on GPU. In order to ensure good performance for the non-overlapping Schwarz method, we propose to use optimized conditions obtained by a stochastic technique based on the covariance matrix adaptation evolution strategy. The performance, robustness, and accuracy of the proposed approach are demonstrated for the solution of the gravitational potential equation for the data acquired from the geological survey of Chicxulub crater.     

Efficient detection of counterfeit products in large-scale RFID systems using batch authentication protocols

RFID technology facilitates processing of product information, making it a promising technology for anti-counterfeiting. However, in large-scale RFID applications, such as supply chain, retail industry, pharmaceutical industry, total tag estimation and tag authentication are two major research issues. Though there are per-tag authentication protocols and probabilistic approaches for total tag estimation in RFID systems, the RFID authentication protocols are mainly per-tag-based where the reader authenticates one tag at each time. For a batch of tags, current RFID systems have to identify them and then authenticate each tag sequentially, one at a time. This increases the protocol execution time due to the large volume of authentication data. In this paper, we propose to detect counterfeit tags in large-scale system using efficient batch authentication protocol. We propose FSA-based protocol, FTest, to meet the requirements of prompt and reliable batch authentication in large-scale RFID applications. FTest can determine the validity of a batch of tags with minimal execution time which is a major goal of large-scale RFID systems. FTest can reduce protocol execution time by ensuring that the percentage of potential counterfeit products is under the user-defined threshold. The experimental result demonstrates that FTest performs significantly better than the existing counterfeit detection approaches, for example, existing authentication techniques.     

Operational characteristics of a top-heat-type long heat transport loop through a heat exchanger

Experimental studies are carried out on the operational characteristics of the top-heat-type long heat transport loop. This loop consists of a heated section, a cooled section, a reservoir, valves and tubes connecting these components. The heated section is about 3 m higher than the cooled section, and water is used as the working fluid inside the loop. Heat is applied from a detached heat source to the heated section by a heat transfer fluid through a heat exchanger, while the heat is discharged from the cooled section to a heat sink. It is confirmed that the temperatures and the pressures inside the loop vary cyclically corresponding to the valve operation, and the heat is transported downward continuously from the heated section to the cooled section. The experimental results are also shown on the effects of the liquid flow rate inside the heat exchanger and the temperatures of the heat source and the heat sink on the operational characteristics of the heat transport loop. Moreover, the discussion is made on the pressure difference inside the loop.     

Mathematical model of heat transfer and feasibility test of improved cooking stoves in Bangladesh

Improved cooking stoves (ICSs) advance the cooking system significantly in Bangladesh. However, the comparative performance analyses of ICSs of Bangladesh are not available in the literature. In this study, heat loss through the stoves was investigated by using ANSYS simulation. From the simulation result, it was found that the average temperature of the wall of ICSs was less than the conventional stove. The maximum thermal efficiencies of some ICSs were found 30%, which is better than other conventional stoves. In addition to this, a feasibility study of ICSs has been carried out by considering cost, greenhouse gas emission and effectiveness of the ICSs. Taken all into consideration, this study would contribute to the literature for further improvement of the stove and guide the consumer to select the appropriate ICS.     

A novel IoT–fog–cloud-based healthcare system for monitoring and predicting COVID-19 outspread

The Journal of Supercomputing - Rapid communication of viral sicknesses is an arising public medical issue across the globe. Out of these, COVID-19 is viewed as the most critical and novel...     

Effects of cathode ray tube display formats on quality‐assurance auditor's performance

The auditing process is a necessary and integral part of a quality‐assurance system. The tendency of using computers in the auditing process is a necessity. This work describes three experiments designed to explore the effects of presenting written material variables on reading speed and comprehension. Five graduate students who consented to participate first completed the font style selection process among six Arabic font styles. “Simplified,” “Traditional,” and “Koufi” font styles were selected from the typography style selection process to be implemented in the next two experiments. Eleven auditors and fourteen undergraduate students with and without knowledge of using computers participated in the second and the third experiments. The font types (Simplified Arabic, Traditional Arabic, and Monotype Koufi) and the font sizes (10, 13, and 16 point) were independent variables in the second experiment. Color combinations (white/black, black/white, blue/white, and white/blue), column types (one and two columns) that are crossed within auditors and naive students were the independent variables in the third experiment. Reading speed, comprehension levels in terms of accuracy of answering recognition and recall questions, and discomfort subjective measures were the dependent variables in both experiments. Results showed that the quality‐assurance auditors were superior to students at reading speed and comprehension. A 13‐point Simplified Arabic font type was better than other font type and font size combinations in terms of reading comprehension and discomfort measure. In addition, white characters on a black background screen color was superior to other character\screen color combinations in terms of reading speed, reading comprehension, and discomfort measure. © 2009 Wiley Periodicals, Inc.     

Transition Metal Complexes of a Novel Polymeric Ligand: Thermal Degradation Kinetics and In Vitro Antibacterial Applications

A novel polymeric ligand poly(2-amino-3-((2-methyl-4-nitrophenylamino)methyl)benzoic acid) was synthesized using solution condensation technique in acid medium. Metal complexes were prepared using the polymer as ligand. The synthesized ligand and its metal complexes were characterized by FTIR, electronic, ESR and NMR (¹H and ¹³C) spectroscopy. The number, weight, size average molecular weights of the ligand were calculated by gel permeation chromatography. The surface morphology and the nature of the synthesized compounds were examined by SEM and XRD. The thermal behavior of the compounds was determined by thermogravimetric analysis. Thermal degradation kinetics such as activation energy (E_a), order of reaction (n) and thermodynamics viz. entropy change (ΔS), apparent entropy (S*), frequency factor (Z) and free energy change (ΔF) were also evaluated for the ligand and its metal complexes by Freeman–Carroll, Sharp–Wentworth methods. Thermal degradation mechanistic model was also proposed by Phadnis–Deshpande method. In vitro antibacterial assay was analyzed for the synthesized compounds against various pathogenic bacterial strains such as Shigella sonnei, Escherichia coli, Klebseilla species, Staphylococcus aureus, Bacillus subtilis and Salmonella typhimurium species. From the assay, the ligand and its metal complexes possess commendable antibacterial activity and hence the synthesized compounds can act as potential antibacterial agents.