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On the high strain rate behavior of 63-37 Sn-Pb eutectic solders with temperature effects

This study presents experimental results performed on samples of Eutectic solder material (63 wt. % Sn 37 wt. % Pb) loaded at high strain rates and elevated temperatures. The tests were performed at high strain rates using Split Hopkinson Pressure Bar (SHPB). The strain rates were in the range of 400 s-1to 1300 s-1. Heating unit was added to conventional SHPB to vary sample' s initial temperature conditions. Tests were conducted at three initial temperatures, i.e. room temperature, 60 °C and 120 °C for compressive mode. The effects of temperature on the behavior of material were compared. Transient temperature changes during dynamic loading conditions are calculated by an analytical approach using measured stress-strain data for plastic work. Test results were fitted into the Johnson-Cook model (JC model). In addition, dynamic tests were performed in tension mode using Split Hopkinson Tensile Bar (SHTB) at room temperature

A REVIEW ON MICROSPONGE DRUG DELIVERY SYSTEM

The drug delivery technology landscape has become highly competitive and rapidly evolving. More and more developments in delivery systems are being integrated to optimize the efficacy and cost-effectiveness of the therapy. Peptides, proteins and DNA-based therapeutics cannot be effectively delivered by conventional means. A Microsponges delivery system is a highly cross-linked, porous, polymeric microsphere, polymeric system consisting of porous microspheres that can entrap and release them into the skin over a long period of time. This delivery system provides extended release with reduced irritation, better tolerance, improved thermal, physical and chemical stability. The main goal of any drug delivery system is to achieve desired concentration of the drug in blood or tissue, which is therapeutically effective and non-toxic for a prolonged period In the present study various methods for preparation of microsponges drug delivery system are studied. Various advantages are also given which shows the importance of this method for the delivery of drugs over the other drug delivery system.  More and more developments in delivery systems are being integrated to optimize the efficacy and cost-effectiveness of the therapy. Microsponge technology offers entrapment of ingredients and is believed to contribute towards reduced side effects, improved stability, increased elegance, and enhanced formulation flexibility. In addition, numerous studies have confirmed that microsponge systems are non-irritating, nonmutagenic, non-allergenic, and non-toxic. Microsponges delivery technology is being used currently in cosmetics, over-the-counter (OTC) skin care, sunscreens and prescription products. One of the best feature of microsponge is it is self-sterilizing. This review is focused on method of preparation, characterization and application of microsponge. Keywords: Microsponge, Control relaease, Target release, topical formulation, oral administratio

Statistical Modeling of SAR Images: A Survey

Statistical modeling is essential to SAR (Synthetic Aperture Radar) image interpretation. It aims to describe SAR images through statistical methods and reveal the characteristics of these images. Moreover, statistical modeling can provide a technical support for a comprehensive understanding of terrain scattering mechanism, which helps to develop algorithms for effective image interpretation and creditable image simulation. Numerous statistical models have been developed to describe SAR image data, and the purpose of this paper is to categorize and evaluate these models. We first summarize the development history and the current researching state of statistical modeling, then different SAR image models developed from the product model are mainly discussed in detail. Relevant issues are also discussed. Several promising directions for future research are concluded at last