Biosorption of Cu(II) ions from industrial effluents by rice husk: experiment, statistical, and ANN modeling

Heavy metal removal from wastewater is a significant research area and recommends sustainable development. The heavy metals cause harmful health effects, increase environmental toxicity. Adsorption is a very effective method for heavy metal removal. A fixed bed for Cu(II) removal using rice hush, an agricultural waste, is reported in this paper. The study was carried out to determine the breakthrough curves with varying operating variables like influent concentration (10–30 mg/L), flow rate (10–40 ml/min), and bed height (4–10 cm) at pH 6. The variation of the process variables like influent concentration, flow rate, and bed height were investigated. The experimental data shows that adsorption capacity increases with the rise of influent concentration. The maximum value of adsorption capacity is 10.93 mg/g at a flow rate of 10 ml/min, bed height 4 cm, and influent concentration 30 mg/L. The applicability of the MLR and ANN modeling has also been successfully carried out. ANN has better predictability than MLR. The findings revealed that rice husk could be used to treat copper-containing industrial effluents

Learning Behavioural Context

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Numerical modelling of dissipation energy of high tensile steel frames against cyclic earthquake excitations

The design of steel structures for ductile response requires (a) materialductility, (b) cross section and member ductility, and (c) structural ductility. Dissipating the earthquake input energy by means of plastic excursions has to be compatible with the plastic deformation capacity of the structure. This work concerns incremental approach of modeling for elastoplastic analysis of structural members subjected to harmonically varying severe earthquake loads and their parametric responses over a range of applied frequencies and amplitudes. Investigations have been carried out in respect of stable and reliable hysteretic energy dissipation mechanisms of high rise steel structures against typical time-history loading of four hypothetical frequencies. Eigen-buckling responses for high rise steel structures subjected to earthquake forces are derived using general purpose software (STAAD). Finally critical structural component is identified for the high rise steel structure for estimation of available in-elastic dissipation energy from material ductility against earthquake excitations. The novelty allows for a very useful generalized formulation for the basic analysis procedures adopted in non-linear material problems. All essential features of a non-linear finite element solution are described in relation to one dimensional model for elasto-plastic beam bending. Solutions techniques are programmed in FORTRAN 90 for Newton-Raphson iteration for non-linear finite element analysis to derive hysteretic energy dissipation of high rise steel structures

Microstructural Characterization of Precipitation Process in a Nickel-Alloy by Non-linear Ultrasonic

The nonlinear ultrasonic technique, using the amplitude ratio of higher harmonic frequencies and fundamental frequency, has been found to be strongly sensitive to the microstructure of bulk materials. It was reported earlier that in Al 2024 alloy the nonlinearity parameter increased with the generation of coherency precipitates. Similarly, Hurley et al reported that the nonlinear parameter linearly increases as a function of inhomogeneous strain due to the generation of a precipitate in low alloy steel. In contrast to these studies, in which researchers have studied ultrasonic nonlinearity in the context of single crystals and simple metals, we would like to study structural materials for the purpose of structural health monitoring. In order to characterize the material properties in facilities and during operation, one needs to understand the relation between the material degradation of structural materials and the features of the NDE parameters. Therefore, in the present study we attempted to assess the thermal degradation in one such structural material namely: Nimonic-263, nickel based precipitation hardenable alloy using the nonlinear technique. From the present study it was found that the response of the non-linear ultrasonic parameter b is faster and larger compared to the normal velocity measurements

FLEET: Butterfly Estimation from a Bipartite Graph Stream

We consider space-efficient single-pass estimation of the number of butterflies, a fundamental bipartite graph motif, from a massive bipartite graph stream where each edge represents a connection between entities in two different partitions. We present a space lower bound for any streaming algorithm that can estimate the number of butterflies accurately, as well as FLEET, a suite of algorithms for accurately estimating the number of butterflies in the graph stream. Estimates returned by the algorithms come with provable guarantees on the approximation error, and experiments show good tradeoffs between the space used and the accuracy of approximation. We also present space-efficient algorithms for estimating the number of butterflies within a sliding window of the most recent elements in the stream. While there is a significant body of work on counting subgraphs such as triangles in a unipartite graph stream, our work seems to be one of the few to tackle the case of bipartite graph streams.Comment: This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in Seyed-Vahid Sanei-Mehri, Yu Zhang, Ahmet Erdem Sariyuce and Srikanta Tirthapura. "FLEET: Butterfly Estimation from a Bipartite Graph Stream". The 28th ACM International Conference on Information and Knowledge Managemen

Asymmetry to symmetry transition of Fano line-shape: Analytical derivation

An analytical derivation of Fano line-shape asymmetry ratio has been presented here for a general case. It is shown that Fano line-shape becomes less asymmetric as \q is increased and finally becomes completely symmetric in the limiting condition of q equal to infinity. Asymmetry ratios of Fano line-shapes have been calculated and are found to be in good consonance with the reported expressions for asymmetry ratio as a function of Fano parameter. Application of this derivation is also mentioned for explanation of asymmetry to symmetry transition of Fano line-shape in quantum confined silicon nanostructures.Comment: 3 figures, Latex files, Theoretica

Large electric-field induced strain in BiFeO3 ceramics

Large bipolar strain of up to 0.36% (peak-to-peak value) was measured in BiFeO3 ceramics at low frequency (0.1 Hz) and large amplitude (140 kV/cm) of the driving field. This strain is comparable to that achievable in highly efficient Pb-based perovskite ceramics, such as Pb(Zr,Ti)O3 and Pb(Mg,Nb)O3-PbTiO3. The strain showed a strong dependence on the field frequency and is likely largely associated with domain switching involving predominantly non-180{\deg} domain walls. In addition, rearrangement of charged defects by applying electric field of low frequency depins these domain walls, resulting in a more efficient switching and, consequently, an increased response

Fabrication of 108^{108}Cd target for the astrophysical p-process studies

The detailed process of preparing enriched $^{108}$Cd targets on mylar and copper backing using the vacuum evaporation technique is described. These targets were employed in an experiment to measure the proton capture cross-section at energies significantly below the Coulomb barrier, for the astrophysical p-process studies. Due to the low melting point and high vapor pressure of cadmium, some adjustments were implemented in the Telemark multipocket e-beam setup. The target thickness was determined through the measurement of alpha particle energy loss from a triple alpha source and also by RBS measurements. The thickness of the $^{108}$Cd films varies between 290 to 660 $\mu$g/cm$^2$, with a non-uniformity of approximately 10$\%$. X-ray Photoelectron Spectroscopy (XPS) and X-ray Fluorescence (XRF) analyses were conducted to examine the presence of impurities and to assess surface morphology, phase, and chemical composition

Nonlinear Lamb wave for the assessment of ratcheting behavior in IF steel

This work demonstrates the use of nonlinear Lamb wave for characterizing the ratcheting behavior in interstitial free (IF) steel. Lamb wave has been used to measure the generated second harmonic component during ratcheting fatigue. A pair of wedge transducers is used to generate and detect the fundamental and second harmonic component of Lamb wave at various interruption of damage and correlation is made with nonlinear ultrasonic parameter. It is seen that acoustic nonlinear parameter evaluated using Lamb wave is very much sensitive to plasticity that has been induced during ratcheting