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In this paper, the free vibration behavior of functionally graded (FG) flat panels subjected to temperature gradient along the thickness direction is investigated by utilizing the temperature independent as well as dependent material properties. The FG panels are modeled using ANSYS commercial package in the framework of first-order shear deformation theory. The convergence and the validity of the present model have been established by comparing the present results with the benchmark results available in published literature. Subsequently, the influence of elevated temperature load, aspect ratio, thickness ratio, and support conditions on the non-dimensional fundamental frequency is investigated by varying the gradient index of the FG panel. The temperature and the consideration of the temperature dependence of the material properties is found have significant influence on the fundamental frequency of the FG panel. The effect of other design parameters on the natural frequency of the FG flat panel under thermal environment has also been examined and discussed in detail.

This study presents the responses of natural frequency on adhesive bonded T-joint structure. For this purpose, free vibration analysis in the T-joint structure have been performed with a three-dimensional finite element method using ANSYS parametric design language (APDL) code. Using Solid 185 element type the structure has been modelled. To verify the accuracy and stability of the present formulation, intensive comparisons are made with existing results available in the literature and good agreements are obtained. Additionally, Influence of various geometrical and material parameters on the dynamic responses of joint structure has been investigated and discussed in detail. It is observed that the natural frequency increases with increase in aspect ratio of the joint structure. Also, the joint made up of Glass fiber/epoxy indicates more resistance towards free vibration.

Polypyrrole, a special class of smart material has gained attention as artificial muscle actuator propulsor due to its promising properties like light weight, flexibility, large dimensional changes with low operating voltage and natural muscle like working and performances. In this paper, a Polypyrrole actuator is fabricated and studied its behaviour and performances in underwater environment experimentally. The actuator is synthesized by electrochemical polymerization and fabricated as a trilayer strip actuator by using layer by layer deposition technique. Following the fabrication, the hydrodynamic bending performances like tip displacement, force and frequency and propulsion characteristics like thrust, power and efficiency are estimated by carried out the bending experiment in a water tank with zero flow velocity. Here the stiffness of the actuator also estimated from dynamic mechanical analysis as it is one of the key parameter which affects the thrust generation. The operation life of the actuator is estimated for underwater operation and analyzes the various parameters and their relation with PPy actuator performances to find the primary controlling parameters. Finally, the present actuator is compared with existing smart material based underwater actuator to study the feasibility of the actuator. From the present study, it can be believe that the proposed PPy actuator propulsor is suitable for underwater bio-inspired robotics motion and may use for various applications like scanning, surveillance and exploration.

An account of three species of Acanthus L. (Acanthaceae) occurring in Bhitarkanika National Park, Odisha is presented in this paper . Acanthus ebracteatus Vahl turned out to be a new distributional record for the Flora of Bhitarkanika National Park and as well as for Odisha state. [ABSTRACT FROM AUTHOR]

This article presents the vibro-acoustic modeling and analysis of un-baffled laminated composite conical shell panels with varying thickness subjected to harmonic point load. The variation of thickness is considered to be unidirectional. A simulation model for the vibrating panel is developed using the commercial finite element package (ABAQUS). The natural frequencies are computed and compared with available published values for validation purpose. Then, the modal values are exported to LMS Virtual.Lab environment where an indirect boundary element approach has been adopted to extract the coupled vibro-acoustic responses. The sound power radiated by the vibrating structure computed using the present scheme is compared with the results available in the published literature. A comprehensive study has been performed to highlight the effect of thickness variation, excitation location, lamination scheme and support conditions on the acoustic radiation responses of the laminated conical shell panel. The variation of thickness is observed to greatly influence the mode shapes of the panel thereby influencing the sound radiation characteristics. The stiffness of the panels is affected by the lamination scheme, which in addition to stiffness variation due to varying thickness alters the radiation characteristics of the panels significantly.

In this paper, the free vibration behavior of functionally graded ceramic-metal sandwich flat panels is investigated. The sandwich panels are considered to be composed of metal rich face layers with varying composition and a homogenous isotropic ceramic core layer. The kinematics of the panels is modeled using ANSYS commercial package. The convergence and the validity of the present model have been established by comparing the present results with the benchmark results available in published literature. Subsequently, the influence of power index, symmetry type and the support conditions on the non-dimensional fundamental frequency is investigated. The fundamental frequency is found to decrease with increasing power index value and increase with number of constraints at the support. The stiffness of the panels is affected by core thickness and the panels with higher core-to-face thickness ratio are observed to have lower fundamental frequency.

In this article, we investigate the thermomechanical deflection characteristics of the debonded composite plate structure using an isoparametric type of higher-order finite element model. The current formulation is derived using higher-order kinematic theory and the displacement variables described as constant along the thickness direction whereas varying nonlinearly for the in-plane directions. The present mid-plane kinematic model mainly obsoletes the use of shear correction factor as in the other lower-order theories. The separation between the adjacent layers is modeled via the sub-laminate technique and the intermittent continuity conditions imposed to avoid the mathematical ill conditions. The governing equation of equilibrium of the damaged plate structure under the combined state of loading are obtained using the variational principle and solved numerically to compute the deflection values. Further, the convergence test has been performed by refining the numbers of elements and validated through comparing the present results with available published values. The usefulness of the proposed formulation has been discussed by solving the different kind of numerical examples including the size, location and position of delamination.

In this study, rutile phase of TiO2 particles have been synthesized by co-precipitation method and is used as an adsorbent for removal of toxic azo dye Eriochrome black-T (EBT) from aqueous solution. The rutile phase of TiO2 was confirmed by the X-ray powder diffraction pattern. Effect of initial dye concentration, adsorbent dose, pH, agitation speed and temperature on the adsorption process of EBT was examined. Removal of EBT was increased by increasing in adsorbent dose and decrease in initial dye concentration and pH. The optimum conditions resulted were: 25 ppm initial dye concentration, 20 mg adsorbent dose and pH of 2. Using Langmuir, Freundlich and Temkin isotherm models, equilibrium data was determined. The Freundlich model showed the best fit for uptake of the EBT dye, which evident that the process of adsorption of EBT dye onto TiO2 particles was heterogeneous. The kinetic data were analyzed using pseudo-first order, pseudo-second order and intraparticle diffusion equation. The pseudo-second order showed the best fit for the kinetic studies (R2 = 0.999), which ascertains that the adsorption process was of chemisorptions type. The intraparticle diffusion model indicated a linear relationship (R2= 0.99) suggesting the pore diffusion to be a limiting step in the overall adsorption process.

Electro-active polymer (EAP) such as Polypyrrole has gained much attention in the category of functional materials for fabrication of both active actuator and sensor. Particularly, PPy actuator has shown potential in fluid medium application because of high strain, large bending displacement and work density. This paper focuses on developing a low cost active actuator promising in delivering high performance in underwater environment. The proposed Au-pyrrole actuator is synthesized by adopting the layer-by-layer electrochemical polymerization technique and is fabricated as strip actuator from aqueous solution of Pyrrole and NaDBS in room temperature. In the follow-up, topographical analysis has been carried out using SEM and FESEM instruments showing surface morphology and surface integrity of chemical components of the structure. Several experiments have been conducted under DC input voltage evaluating performance effectiveness such as underwater bending displacement and tip force etc. This is observed that the actuator exhibits quite similar stress profile as of natural muscle, endowed with high modulus makes them effective in working nearly 10,000 cycles underwater environment. In addition, the bending displacement up to 5.4 mm with a low input voltage 1.3 V makes the actuator suitable for underwater micro-robotics applications.

The paper proposes a modified approach of delineation and classification of two different types of liver cancers viz. Hepatocellular Carcinoma (HCC) and Metastatic Carcinoma (MET) from different slices of computed tomography (CT) scans images. A combined framework of reorganization and extraction of region of interest (ROI), texture feature extraction followed by texture classification by different machine learning approaches has been presented. Initially, adaptive thresholding has been applied to segment the liver region from CT images. Level set algorithm has been used for detecting the region of cancer tissues. In the classification stage, the delineated output lesions have been extracted with 38 features to build up the dataset. Two machine learning classifiers, support vector machine (SVM) and random forest (RF), have been used to train the dataset for correct prediction of cancer classes. Ten-fold cross-validation has been used to evaluate the performance of two classifiers. The efficiency of the proposed algorithm is tested in terms of accuracy, where the RF classifier achieved a higher accuracy of 95% compared to SVM classifier of 87%. The experimental result proves the superiority of RF classifier compared to SVM classifier with level-set features.

The bending strength and deformation characteristics of the debonded laminated plate under the uniformly distributed loading (UDL) have been investigated in this research article. For the simulation study, an internally damaged laminated plate structure model has been developed in ANSYS based on the first-order shear deformable kinematic theory via ANSYS parametric design language (APDL) code. The internal debonding within the laminated structure is incorporated using two sub-laminate approach. Further, the convergence (different mesh densities), as well as the validity (comparing the responses with published results) of the present simulation model, have been performed by solving the deflection responses under the influence of transversely loaded layered structure. Also, to show the coherence of the simulation analysis the results are compared with the experimental bending results of the homemade Glass/Epoxy composite with artificial delamination. For the experimental analysis, Glass/Epoxy laminated composite seeded with delamination at the central mid-plane of the laminate is fabricated using an open mould hand lay-up composites fabrication technique. For the computational purpose, the necessary material properties of fabricated composite plate evaluated experimentally via uniaxial tensile test (Universal Testing Machine INSTRON-1195). Further, the bending (three-point bend test) test is conducted with the help of Universal Testing Machine INSTRON-5967. Finally, the effect different geometrical and material parameters (thickness ratio, modular ratio, constraint conditions) and magnitude of the loading on the static deflection and stress behaviour of the delaminated composite plate are investigated thoroughly by solving different kinds of numerical illustrations and discussed in detail.

In the present investigation, static bending and strength behaviour of the laminated composite plate embedded with magnetostrictive (MS) material has been computed numerically using commercial finite element tool. For the analysis purpose, a simulation model of the laminated plate embedded with and without MS material is derived using the batch input technique popularly termed as ANSYS parametric design language (APDL). The MS bonded composite model is discretised with the help of available suitable element from ANSYS element library. The elements are chosen suitably by considering the compatibility between the mechanical and the magnetic fluxes indices. For the calculation of the necessary responses, APDL code has been prepared in ANSYS environment. Further, the stability of the model has been checked by computing the responses for various mesh sizes. Subsequently, the accuracy of the model has also been checked by conducting the comparison test. For the comparison, central deflection of the clamped Graphite/Epoxy laminated plate embedded with Terfenol-D has been evaluated and compare them with those of the available earlier published literature. The comparison study clearly indicates that, the present responses are in-line and showing good agreement with that of the reference. Further, the versatility and the applicability of the simulation model has been proven by solving the different illustrations. In the illustration, the influence of the different geometrical parameter such as thickness ratio and aspect ratio on the bending behaviour has been investigated and discussed in detail.

In the present study, the free vibration and the bending behaviour of carbon nanotube reinforced composite plate are computed using three different shear deformation theories under thermal environment. The material properties of carbon nanotube and matrix are assumed to be temperature-dependent, and the extended rule of mixture is used to compute the effectivematerial properties of the composite plate. The convergence and validity of the present modelalso have been checked by computing the wide variety of the numerical example. The applicability of the proposed higher-order models has been highlighted by solving the wide variety of examples for different geometrical and material parameters underelevated thermal environment.The responses are also examined using the simulation model developed in commercial finite element package (ANSYS).

We have analysed the free vibration responses of the laminated composite plate with delamination numerically and validated with subsequent experiment. In order to compute the numerical frequencies, the delaminated composite plate is modelled with two sub-laminate approaches in the commercial finite element package (ANSYS) using ANSYS parametric design language code in ANSYS environment. For the experimental analysis, the woven Glass/Epoxy composite plate is fabricated using hand layup method with the desired delamination. The natural frequencies of the delaminated plate are also computed experimentally with the help of the vibration analyser (NI-CDAQ) and validated by comparing with the simulation result. Further, the simulation model is extended for various design parameter and discussed in detail.

A simple, precise, accurate, economical and reproducible HPLC method for estimation of montelukast in tablet dosage form has been developed. Quantitative HPLC was performed with Shimadzu LC2010c HT with Winchrom Software with UV-Visible detector (SPD-IOA), PUMP (LC-IOAT) and (LC-IOATvp). Phenomenex C8, 5 μm, 25 cm × 4.6 mm i.d. column was used in the study. The mobile phase of ACN: Acetate buffer= 6.5:3.5 of pH 3 were used in this study. The conditions optimized were: flow rate (1 mL/minute), wavelength (222 nm) and run time was 20 min. Retention time was found to be 3.08 min. The linearity was found to be in the concentration range of 10-100 μg/mL. The developed method was evaluated in the assay of commercially available tablet moni containing 10 mg of montelukast. The amount of drug in tablet was found to be 10.34 mg/tab for the brand. Results of analysis were validated statistically and by recovery studies. The recovery studies 99.67% was indicative of the accuracy of proposed method. The precision was calculated as repeatability, inter and intraday variation (%RSD) for the drug. By using the method, stability of the drug has been studied.

The compounds 2-[5'-benzylidene-2'-phenyl-4'-oxo-1', 3'-thiazolidine]-1, 3-benzothiazole and 2-[5'-(p-N,N-dimethylamino- benzylidene)-2'-phenyl-4'-oxo-1', 3'-thiazolidine]-1, 3-benzothiazole have been synthesized in their purest forms starting from 2-aminobenzothiazole. The inclusion complexes of the above compounds have been prepared with β-cyclodextrin to increase their solubility and bioaccessibility in polar medium. The formation of inclusion complexes have been ascertained by study of spectral characteristic before and after inclusion complex formation. The stability of inclusion complexes and nature of interaction between the host and guest are known from the determination of thermodynamic parameters. Further the antibacterial and antifungal activities of the compounds are determined which is found to increase significantly after inclusion complex formation

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