Improved description and monitoring of near surface hazardous infiltrate complexes by shear waves for effective containment reponse

Among numerous causes of fluid releases and infiltration in near surface, resurgence in such anthropic activities associated with unconventional resource developments have brought about a resounding concern. Apart from the risk of an immediate chemical hazard, a long term possible recurrent geo-environmental risk since can also be envisaged as for various prevalent stake holders and broader initiatives. Urgency and exactness for spatiotemporal containment and remediation promotes the devising of efficient methods for monitoring near subsurface flow complexes caused by such spills. Swave (Shear waves) spectral imaging results, in relevant context, of a controlled immiscible fluid displacement monitoring experimental study are analysed and inferred. Against the prospective method as well evaluated, Swave diffraction associated spectral peculiarities are examined, importantly, given background medium characteristics definitions invoking fresh insights of microscale significance alongside macroscale potential

Applications of acoustics in the measurement of coal slab thickness

The determination of the possibility of employing acoustic waves at ultrasonic frequencies for measurements of thicknesses of slabs of coal backed by shale is investigated. Fundamental information concerning the acoustical properties of coal, and the relationship between these properties and the structural and compositional parameters used to characterize coal samples was also sought. The testing device, which utilizes two matched transducers, is described

The transmissibility of vibration isolators with a nonlinear anti-symmetric damping characteristic

In the present study, the concept of the Output Frequency Response Function (OFRF), recently proposed by the authors, is applied to theoretically investigate the transmissibility of SDOF passive vibration isolators with a nonlinear anti-symmetric damping curve. The results reveal that a nonlinear anti-symmetric damping characteristic has almost no effect on the transmissibility of SDOF vibration isolators over both low and high frequency ranges where the frequencies are much lower or higher than the isolator’s resonant frequency. On the other hand, the introduction of a nonlinear anti-symmetric damping can significantly reduce the transmissibility of the vibration isolator over the resonant frequency region. The results indicate that nonlinear vibration isolators with an anti-symmetric damping characteristic have great potential to overcome the dilemma encountered in the design of passive linear vibration isolators, that is, increasing the level of damping to reduce the transmissibility at the resonance could increase the transmissibility over the range of higher frequencies. These important theoretical conclusions are then verified by simulation studies

Emerging technologies for the non-invasive characterization of physical-mechanical properties of tablets

The density, porosity, breaking force, viscoelastic properties, and the presence or absence of any structural defects or irregularities are important physical-mechanical quality attributes of popular solid dosage forms like tablets. The irregularities associated with these attributes may influence the drug product functionality. Thus, an accurate and efficient characterization of these properties is critical for successful development and manufacturing of a robust tablets. These properties are mainly analyzed and monitored with traditional pharmacopeial and non-pharmacopeial methods. Such methods are associated with several challenges such as lack of spatial resolution, efficiency, or sample-sparing attributes. Recent advances in technology, design, instrumentation, and software have led to the emergence of newer techniques for non-invasive characterization of physical-mechanical properties of tablets. These techniques include near infrared spectroscopy, Raman spectroscopy, X-ray microtomography, nuclear magnetic resonance (NMR) imaging, terahertz pulsed imaging, laser-induced breakdown spectroscopy, and various acoustic- and thermal-based techniques. Such state-of-the-art techniques are currently applied at various stages of development and manufacturing of tablets at industrial scale. Each technique has specific advantages or challenges with respect to operational efficiency and cost, compared to traditional analytical methods. Currently, most of these techniques are used as secondary analytical tools to support the traditional methods in characterizing or monitoring tablet quality attributes. Therefore, further development in the instrumentation and software, and studies on the applications are necessary for their adoption in routine analysis and monitoring of tablet physical-mechanical properties