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61.
62.
In the fluidised bed granulation process the effect of nozzle air pressure and binder spray rate on key aggregate quality attributes were studied. The experimental results show that a decrease in nozzle air pressure leads to larger mean granule size. The combination of lowest nozzle air pressure and lowest binder spray rate results in granules with the highest levels of hardness and crispness. The combination of low nozzle air pressure and low binder spray rate results in the least distribution span. Granola hardness was affected by nozzle air pressure. Nozzle air pressure and binder spray rate did not have significant effect on crispness.  相似文献   
63.
Present paper reports the synthesis of nanostructured (Sn–Ti)O2 via physicochemical method, its characterization and performance as liquefied petroleum gas (LPG) sensor. The synthesized material was characterized using XRD that confirmed the formation of (Sn–Ti)O2 nanocomposite. Minimum crystallite size was found as 7 nm. The material was also investigated through SEM, DSC, FTIR, PL and UV–Vis spectrophotometer. Further, the pellet, thick and thin films were fabricated for the sensing analysis. Pellets (9 mm diameter, 4 mm thickness) of (Sn–Ti)O2 nanocomposite were made by hydraulic pressing machine by applying uniaxial pressure of 616 MPa, thick films (thickness ~2 µm) were made by screen printing technique and thin films were prepared using a Photo resist spinner unit. Further at room temperature, the pellet and films were exposed to LPG in a gas chamber under controlled conditions at room temperature and variations in resistance with the concentrations of LPG were observed. The maximum value of sensitivity of solid state pellet, thick and thin films based sensors were found 7, 9 and 39 for 5 vol% of LPG, respectively. Sensing characteristics were found to be reproducible, after 6 months of their fabrication, indicating the stability of the sensors.  相似文献   
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By studying temperature-dependent dispersion characteristics and group velocity of 1D ternary photonic crystal (TPC) composed of dielectric-superconductor-dielectric materials, a thermally tunable band-stop filter which is capable of stopping unique wavelength channels without causing any interference amongst equally spaced wavelength channels of full width at half maximum of 1 nm each as per the requirement of wavelength division multiplexing standards adopted by the International Telecommunication Union specifying channel spacing in terms of frequency (wavelength) is suggested. The proposed structure can efficiently work as a two-channel wavelength selective switch for wavelength division multiplexing (WDM)-based all-optical networks. This study also gives theoretical insight to design some new kind of optical memories and tunable buffers which holds data temporary and have potential applications in modern communication systems.  相似文献   
66.
Drug which shows extensive first pass effect is difficult task that, needs to be solved by formulators in the pharmaceutical science. The low oral bioavailability (49%) of flutamide may be due to poor wettability, low aqueous solubility and extensive first pass effect. The aim of present investigation was to prepare flutamide loaded microspheres and incorporate it into suppositories for rectal delivery to avoid first pass effect and enhance residence time. Flutamide loaded mucoadhesive microspheres of Ocimum Basilicum mucilage (OBM) were prepared using spray drying and characterized by percent production yield, encapsulation efficiency, particle size, zeta potential, polydispersity index, DSC, SEM, XRPD, in vitro drug release and stability studies. Moreover, ex vivo mucoadhesion was investigated using falling liquid film technique to determine the adhesion of microspheres to sheep rectal mucosa. The microspheres had nearly spherical shape and size about 2.53?μm. The encapsulation efficiency and mucoadhesion of optimized formulation MBF10 were found to be 69.6?±?2.3% and 89.01?±?2.18%, respectively. Percent CDR of optimized flutamide loaded mucoadhesive microspheres was found to be 88.7?±?1.3 at 7?h. In conclusion, OBM microparticles based suppository could be used to deliver drug through rectal delivery.  相似文献   
67.
This article presents the deformation behavior of high-strength pearlitic steel deformed by triaxial compression to achieve ultra-fine ferrite grain size with fragmented cementite. The consequent evolution of microstructure and texture has been studied using scanning electron microscopy, electron back-scatter diffraction, and X-ray diffraction. The synergistic effect of diffusion and deformation leads to the uniform dissolution of cementite at higher temperature. At lower temperature, significant grain refinement of ferrite phase occurs by deformation and exhibits a characteristic deformation texture. In contrast, the high-temperature deformed sample shows a weaker texture with cube component for the ferrite phase, indicating the occurrence of recrystallization. The different mechanisms responsible for the refinement of ferrite as well as the fragmentation of cementite and their interaction with each other have been analyzed. Viscoplastic self-consistent simulation was employed to understand deformation texture in the ferrite phase during triaxial compression.  相似文献   
68.
A model was developed to simulate oxygen accumulation in space and time within cylindrical dynamic accumulation chambers that are used to measure oxygen transmission rate (OTR) of materials. The model is based on Fick's law of diffusion and was validated against actual OTR measurements of polymer film samples. Measured OTR values and thicknesses were inputted into the model and oxygen concentrations outputted by the model. OTRs determined from the output of the model was in close agreement to within 0.3–3% of the measured OTR. Oxygen concentration versus time curves generated from model output oxygen concentrations and experimentally measured oxygen concentrations for three actual films were also in agreement. The model was then used to simulate results from three hypothetical test films at varying chamber lengths in order to evaluate effects of accumulation chamber dimensions relative to films on resulting OTR measurements. A typical design scenario was used, where the oxygen sensor is mounted on the chamber wall opposite the sample film. Results demonstrate that dynamic accumulation OTR instrument designers have considerable flexibility in choosing accumulation chamber dimensions because deviations in OTR are only expected to occur at impractically extreme chamber lengths (>10 m) for the entire envelope of OTRs expected for typical packaging films. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
69.
70.
There are various methods to determine the compressive and tensile strength of asphalt concrete under static loading conditions and most studies on asphalt strength and fracture have been conducted under such loading conditions. However, pavement materials also have to withstand a wide variety of loading and temperature conditions which may vary from quasi-static to high-strain rate impact, and pavement breakdown may occur due to fracture and/or fatigue failure. In the present study, a bituminous mix with 30% RAP has been characterized under quasi-static (10?3–10?4 strain/s) and high-strain rate (200–700 strain/s) regimes. The experimental studies have been performed to better understand the compressive, tensile and fracture response of bituminous mixes. Split Hopkinson pressure bar (SHPB) and its modifications were used for high-strain rate characterization of this bituminous mixture. It was observed that the mechanical properties of the hot mix asphalt (HMA) changed significantly under high-strain rate testing. Also, the failure mechanisms observed under the high-strain rate loading were found to be considerably different from those obtained in static testing, where failure of binder was a predominant mechanism. It was observed that high-strain rate loading caused trans-aggregate failures in the specimens; in addition to failure of the binder.  相似文献   
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