In this study the effects of different intensities and exposure time of ultrasound on barley seed have been investigated to determine the optimal conditions for accelerating germination. For optimization, the Taguchi approach was used. The germination rates and/or yield of the treated sample seed were compared with those of the untreated seed germinated under normal conditions. The seeds were treated with ultrasonic energy (input power 20-90% of 460W) and were exposed to three time periods ranging from 5 to 15 min. It was found that germination of the treated barley seed was increased about 1.042-1.065 times compared with that of the untreated seed. The ultrasonic treatment proved to be efficient in reducing the germination period by 30-45%. It was concluded that priming of seeds with ultrasound was effective in improving water uptake and germination. The data presented in this paper suggest that the increase in final germination percentage, together with the reduced germination period in treated seeds, may be due to the action of ultrasound and that it led to an improved hydration process with concurrent shell fragmentation.

Highly-dispersed platinum and platinum-based catalysts on a conductive support are commonly used as electrode materials in low-temperature fuel cells, particularly the hydrogen PEMFC and the direct methanol PEMFC. The performance and durability/stability of these catalysts strongly depend on the characteristics of the support. Catalysts supported on high surface area carbon black are widely used in low-temperature fuel cells. However, the corrosion of carbon black has been recognized as one of major causes of performance degradation and durability issues of low-temperature fuel cells under high-potential conditions. So the need for alternative supports with outstanding physical and mechanical properties to carry out the successful reaction in catalyst layer and give a longer lifetime for the electrocatalysts is inevitable. The emergence of nanotechnology and development of nanostructure materials in recent years has opened up new avenues of materials development for low-temperature fuel cells. This paper presents the performance with a variety of carbon-based nanostructured materials such as carbon nanotubes (CNT), carbon nanofibers (CNF), carbon aerogels, nanoplates of graphene, etc. So the present paper provides an overview of these nanostructured materials as low-temperature fuel cell catalyst supports. The improved characteristics of the nanostructured supports with respect to commercially used carbon black (Vulcan XC-72) and their effect on the electrochemical activity are highlighted. Additionally, it reviews the literature on the synthesis of nanostructured-supported Pt electrocatalysts for proton exchange membrane (PEM) fuel cell catalyst loading reducing through the improvement of catalyst utilization and activity. The features of each synthetic method were also discussed based on the morphology of the synthesized catalysts.

The effects of ultrasound as emerging technology along with thermal treatment were investigated on the activity of barley's alpha-amylase after germination. All experiments were carried out at 20 kHz on an ultrasonic generator by considering the three effective factors, temperature (30, 50 and 70 o C) and ultrasonic intensities (20, 60 and 100% setting from total power of device (460 W)) in different time intervals (5, 10 and 15 min). For determining the effects of these parameters, the enzymatic activity was assayed by measuring the reducing sugars released as a result of the alpha-amylase action on soluble starch using 3,5-dinitrosalicylate regent (DNS). The results of these assays were analyzed by Qualitek4 software by using the Taguchi statistical method to evaluate the factor's effects on the enzyme activity. Consequently, the results of assays showed that the activity of this enzyme from germinated barley was reduced after thermosonication by comparing to the blank.

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