Thermal Analysis of Ductile Iron Casting

Pure metals solidify with a solidification front that is very well defined and a clearly delineated solid-liquid interface. Ductile cast iron solidification is characterised by a very thin solidified skin and appearance of different phases. The outer skin is formed being very thin in ductile iron; the expansion occurs due to graphite nucleation into the casting forces to the mould walls. With proper care taken while designing and during melt processing stage, quality ductile iron castings can be produced with minimal risering. With recent developments in sensing and storing instruments, it is now possible to see and measure structural transformations within the solidification in ductile iron castings very precisely. The shape of a cooling curve measured by a thermocouple mounted on a thermal analysis sample cup reflects the solidification process of the melted cast alloy for the given solidification conditions. By analysing particular cooling curve, the solidification start, eutectic arrests, recalescence, amount of undercooling and end of freezing temperature temperatures are generated. The thermal analysis data so generated will be used to study composition, soundness, chill and microstructure by analysis of cooling curve. The cooling rates measured in degrees per second at different stages of solidification sequence will be analysed and correlated with the properties of the castings to be produced from the same melt

Hall effect in cobalt-doped TiO2−δ_{2-\delta}

We report Hall effect measurements on thin films of cobalt-doped TiO$_{2-\delta}$. Films with low carrier concentrations (10$^{18}$ - 10$^{19}$) yield a linear behavior in the Hall data while those having higher carrier concentrations (10$^{21}$ - 10$^{22}$) display anomalous behavior near zero field. In the entire range of carrier concentration, n-type conduction is observed. The appearance of the anomalous behavior is accompanied by a possible structural change from rutile TiO$_{2}$ to Ti_[n}O$_{2n-1}$ Magneli phase(s)

ANTIPROLIFERATIVE ACTIVITY OF ELEPHANTOPUS SCABER MEDIATED SILVER NANOPARTICLES AGAINST MCF-7, A-549, SCC-40, AND COLO-205 HUMAN CANCER CELL LINES

Objective: To unearth the applications of nanotechnology in medicine has become imperative with all the advancements in the technique. In the current study, we have attempted to exploit the anticancer ability of the green synthesized silver nanoparticles (AgNPs). Methods: The AgNPs were synthesized using 60% methanol (H-MeOH) Elephantopus scaber leaf extract, characterized, and discussed priorly. The effect of AgNPs was studied on the human breast (MCF-7), lung (A-549), oral (SCC-40), and colon (COLO-205) cancer cell lines through sulforhodamine B assay. We also carried out the synergistic activity with standard drug adriamycin (ADR). Results: According to the results obtained, AgNPs showed good antiproliferative activity with GI50 <10 μg/ml on MCF-7, A-549, and SCC-40 cell lines when compared with the standard drug ADR. However, for COLO-205 cell line, the impact was 17.4 μg/ml and thus the treatment was less effective. Conclusion: The synergistic effect of AgNPs+ADR was even better for all the four cell lines than that of the AgNPs alone

Test Case Prioritization Based on Specific Events

Event-Driven Software (EDS) system changes its state according to arrival of events for example graphical user interface and web framework. So due to there are number of events generated by users waiting in queue, this system is raise issue for testing. Until now, there are more efforts taken for testing this issue but these efforts are not collective. In this project work, our try is to give collective solution for graphical user interface and Web frameworks combined. We designed model to test graphical user interface and web application combined by using test cases prioritization. Main objective is here to deploy this model to prioritize test cases based on events. Our proposed work shows that graphical user interface and Web-based frameworks, gives same behavior even after prioritization. To test stand-alone GUI and Web-based frameworks based on shared prioritization function, and prioritization criteria’s. This generic approach is enough to study develop and test a unified theory for all kinds of Event Driven Software systems. This paper articulates all the details regarding our proposed system through following sections

Searching and fixating: scale-invariance vs. characteristic timescales in attentional processes

In an experiment involving semantic search, the visual movements of sample populations subjected to visual and aural input were tracked in a taskless paradigm. The probability distributions of saccades and fixations were obtained and analyzed. Scale-invariance was observed in the saccadic distributions, while the fixation distributions revealed the presence of a characteristic (attentional) time scale for literate subjects. A detailed analysis of our results suggests that saccadic eye motions are an example of Levy, rather than Brownian, dynamics.Comment: Accepted to Europhysics Letters (2011

FORMULATION AND EVALUATION OF FLOATING MICROSPHERES OF CIPROFLOXACIN BY SOLVENT EVAPORATION METHOD USING DIFFERENT POLYMERS

Objective: The main intention of this research was to formulate and evaluate floating microspheres of ciprofloxacin using different polymers to prolong gastric residence time. Methods: The microspheres were formulated by the solvent evaporation method using different ratios of polymers like carbopol 940, ethylcellulose, and Hydroxy Propyl Methyl Cellulose K4M. Further, the floating microspheres were evaluated for micromeritic properties like bulk density, tapped density, angle of repose, etc., percentage yield, particle size, entrapment efficiency, floating capacity, in vitro drug release study, release kinetics, drug content, swelling index, and Fourier Transform Infrared Spectroscopy (FTIR) (Compatibility studies). Results: The ciprofloxacin microspheres showed the good flowing property. The particle size ranged from 258.1±2.21 µm to 278±2.86 µm and entrapment efficiency ranged from 63.17±0.43% to 89.90±1.32%. The IR spectrum revealed that there was no interaction between the drug and polymer. F7 formulation was found to be the best formulation. Drug release was found to be 90.70±0.89% i.e. in a controlled manner at the end of 10 h. Conclusion: The floating microspheres were prepared successfully and the results clearly stated that prepared ciprofloxacin microspheres may be safe and effective controlled drug delivery over an extended period which can increase bioavailability, patient compliance, and decrease dosing frequency

FORMULATION OF SOLID DISPERSIONS FOR ENHANCEMENT OF SOLUBILITY AND DISSOLUTION RATE OF SIMVASTATIN

Objective: The objective of the present work was to formulate the solid dispersions of simvastatin for enhancement of its aqueous solubility and dissolution rate. Methods: In the present study, solid dispersions of simvastatin were prepared by Kneading and Solvent evaporation methods. The polymeric carriers like Polyethylene glycol (PEG) 6000 and Polyvinyl Pyrrolidone (PVP) K30 were used in different ratios (ratio of drug: carrier was 1:1, 1:2) to formulate solid dispersions. The prepared solid dispersions were characterized by differential scanning calorimetry (DSC), Fourier transforms infrared spectroscopy (FTIR), and evaluated for drug content, percentage yield, saturation solubility, in vitro dissolution studies. The best formula of the solid dispersion was selected according to the solubility and dissolution data. Results: The F7 formulation was found to be an optimized formulation containing PVP K30 in the ratio 1:1 prepared by solvent evaporation technique. The Drug content was found to be higher i.e. 94.89 in the F7 batch. The FT-IR spectra revealed that there was no interaction between drugs and carriers. DSC thermogram indicated entrapment of simvastatin in PVP K30 and the conversion of crystalline simvastatin into an amorphous form. The F7 formulation showed maximum drug release i.e. 98.60% in 60 min which is 2 times greater than pure drug making it an optimized formulation. Conclusion: The solubility of simvastatin was successfully enhanced through the solid dispersion technique. Solid dispersions prepared with solvent evaporation method were more soluble than solid dispersions prepared with kneading method with carrier PVP K30

Coarse grained dynamics of the freely cooling granular gas in one dimension

We study the dynamics and structure of clusters in the inhomogeneous clustered regime of a freely cooling granular gas of point particles in one dimension. The coefficient of restitution is modeled as $r_0<1$ or 1 depending on whether the relative speed is greater or smaller than a velocity scale $\delta$. The effective fragmentation rate of a cluster is shown to rise sharply beyond a $\delta$ dependent time scale. This crossover is coincident with the velocity fluctuations within a cluster becoming order $\delta$. Beyond this crossover time, the cluster size distribution develops a nontrivial power law distribution, whose scaling properties are related to those of the velocity fluctuations. We argue that these underlying features are responsible behind the recently observed nontrivial coarsening behaviour in the one dimensional freely cooling granular gas.Comment: 7 Pages, 9 Figure