Computer model for the characterisation of the size distribution of spheroidal graphite in ductile cast iron

A computer model was developed to establish the relationship between the two-dimensional (2D) and the three-dimensional (3D) parameters, specifically the number of particles and particle size distribution. The computer experiments were performed for both monodispersed and lognormally polydispersed systems. The model was based on a random distribution of a number of spherical grains in a cubic unit, with no intersection between the grains. The cubic unit was cut by a random plane and the number of particles which appeared in the section and the area fraction were measured. This procedure was repeated until the average number of particles and the average area fraction became constant. Finally, the 2D size distribution of the particles over all sections was obtained.

It was concluded that the volume fraction is equal to the area fraction, irrespective of the particle size distribution, providing that the total number of measured 2D particles is large enough. As for the number of particles, an equation was found to calculate the number of 3D particles in a monodispersed system from the number of 2D particles and the volume fraction. However, in lognormally polydispersed systems the number of 3D particles could be calculated using the 3D mean and standard deviation, estimated from the 2D mean and standard deviation by a method specifically developed for the purpose.

Finally, the method was applied to two ductile cast iron specimens and the applicability of the present model was verified.     

An Efficient Data Delivery Scheme in WBAN to Deal with Shadow Effect due to Postural Mobility

The body movement and change in posture exhibit high mobility in sensor nodes which causes shadowing in the Wireless Body Area Network (WBAN). Due to this, the connectivity between the nodes in WBAN is affected which further causes failure in data delivery. This article presents a MAC protocol in WBAN to deal with the problem of data delivery due to body movement and postural mobility. It uses an Improved Initial Centroid K-means clustering technique for classification of various human body postures followed by back propagation neural network as a classifier to recognize human body posture. This article proposes a posture aware dynamic data delivery (PA-DDD) protocol to deliver data dynamically. The PA-DDD protocol can be used under varying speed walking scenario. The simulation results show that it prolongs the network lifetime and is energy efficient.

     

An Energy Efficient QoS Supported Optimized Transmission Rate Technique in WBANs

Wireless Personal Communications - The Wireless Body Area Networks (WBANs) provide an unprecedented opportunity for ubiquitous real-time health-care and fitness monitoring without impairing the...     

Immune response to chemically modified proteome

Both enzymatic and nonenzymatic PTMs of proteins involve chemical modifications. Some of these modifications are prerequisite for the normal functioning of cell, while other chemical modifications render the proteins as “neo-self” antigens, which are recognized as “non-self” leading to aberrant cellular and humoral immune responses. However, these modifications could be a secondary effect of autoimmune diseases, as in the case of type I diabetes, hyperglycemia leads to protein glycation. The enigma of chemical modifications and immune response is akin to the “chick-and-egg” paradox. Nevertheless, chemical modifications regulate immune response. In some of the well-known autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis, chemically modified proteins act as autoantigens forming immune complexes. In some instances, chemical modifications are also involved in regulating immune response during pathogen infection. Further, the usefulness of proteomic analysis of immune complexes is briefly discussed.     

Novel processing,testing and characterization of copper/carbon nanotube (Cu/CNT) yarn composite conductor

Sustainable electrified aircraft propulsion (EAP) is likely to lead to an increase in the electrical wiring contained within a single aircraft. Since the electrical resistance and mass of copper (Cu) conductors are associated with power losses, it is desirable to design high-conductivity lightweight conductor materials, thus reducing the mass of components like motor windings, low-voltage signal cables, and transmission cables for data and power to improve the overall energy efficiency. This paper describes a unique framework for manufacturing metalized carbon nanotube (CNT) composite conductors, measuring their electrical conductivity and strength, and modeling the overall conductivity and current sharing within such composites. Tensile testing was conducted on the processed composite conductor cables with the use of acoustic emission and electrical resistivity to determine stress-dependent-failure mechanisms while monitoring the electrical conductivity. The average of measured electrical conductivities of annealed Cu/CNT samples from batch 5 was greater than theoretical predictions by 9.8 percent and was also greater than the conductivity of pure annealed Cu by 4.8 percent and had comparable ultimate tensile strengths. Additionally, those Cu/CNT samples provide a 13.5% weight saving over current state of the art copper wires. Theories explaining improved intrinsic conductivity are discussed.     

Heterogeneous Cubic Multidimensional Integrated Circuit for Water and Food Security in Fish Farming Ponds

Among major food production sectors, world aquaculture shows the highest growth rate, providing more than 50% of the global seafood market. However, water pollution in fish farming ponds is regarded as the leading cause of fish death and financial losses in the market. Here, an Internet of Things system based on a cubic multidimensional integration of circuit (MD‐IC) is demonstrated for water and food security applications in fish farming ponds. Both faces of the silicon substrate are used for thin‐film‐based device fabrication. The devices are interconnected via through‐silicon‐vias, resulting in a bifacial complementary metal‐oxide‐semiconductor‐compatible electronics system. The demonstrated cubic MD‐IC is a complete, small, and lightweight system that can be easily deployed by farmers with no need for specialists. The system integrates on its outer sides simultaneous air and water quality monitoring devices (temperature, electrical conductivity, ammonia, and pH sensors), solar cells for energy‐harvesting, and antenna for real‐time data‐transfer, while data‐management circuitry and a solid‐state battery are integrated on its internal faces. Microfluidic cooling technology is used for thermal management in the MD‐IC. Finally, a biofriendly polymeric encapsulation is used to waterproof the embedded electronics, improve the mechanical robustness, and allow the system to float on the surface of the water.     

Packet Scheduling Scheme to Guarantee QoS in Internet of Things

Wireless Personal Communications - In this paper, a new prediction based dynamic scheduling mechanism is proposed to ensure quality of service especially in internet of things (IoT) by dynamically...     

Antioxidant and antithrombotic effects of green mussels (Perna canaliculus) in rats

In the past decade, the use of marine mussels as seafood is being more popular. They considered being a rich source of various nutritional bioactive compounds that aroused the scientific community's interest. This study investigated the antioxidant and the antithrombotic consequences on Sprague-Dawley male rats after adding dried New Zealand mussel Perna canaliculus in their diet. The biochemical, hematological and histopathological changes were also observed. Forty rats were divided into four groups according to the amount of dried mussels in their diet, in addition to a control group that consumed a basal diet only. Group 1 consumed 25% dried mussels in its basal diet; Group 2 consumed 35% dried mussels in its basal diet, and Group 3 was consumed 45% dried mussels in its basal diet. The biochemical parameters showed improvements in liver function. Interestingly, the lipid profile decreased, especially the low-density lipoprotein cholesterol (LDL-C) levels which were reduced significantly in Group 3 (p < .01). These observations were accompanied by a decrease in iron levels significantly as the amount of dried mussels increased (p < .01). Furthermore, the noticed changes in the hematological profile prove that there is an increase in antithrombotic activity. Dried mussels had potent antioxidant effects in the liver as shown by increased lipid peroxide (p < .05), reduced glutathione (p < .05), and glutathione peroxidase (GSH-Px; p < .05). Additionally, antioxidant activity in the kidney was shown to increase through GSH-Px activity (p < .01). In conclusion, these results indicate that consuming dried mussels resulted in improved biochemical and antioxidants activities and could be used as an antithrombotic agent.     

Vapor phase synthesis of methylpyrazine using aqueous glycerol and ethylenediamine over ZnCr2O4 catalyst: Elucidation of reaction mechanism

A novel method has been developed for the synthesis of methylpyrazine (MP) by using aqueous glycerol and ethylenediamine (EDA) over Zn–Cr catalyst derived from hydrotalcite precursors. The X-ray diffraction analysis of the oven-dried Zn–Cr samples synthesized at various pH ranging from 7 to 11 showed hydrotalcite phase whereas the calcined catalysts displayed ZnO and ZnCr₂O₄ phases. The cyclisation activity of Zn–Cr catalyst prepared at pH ~ 9 demonstrated 99.4% conversion of EDA and 94% of glycerol with ~ 72% selectivity to MP at a reaction temperature of 400 °C. This process demonstrates direct utilization of bio-glycerol for the synthesis of MP.     

Organic nanostructures on silicon, created with semitransparent polystyrene spheres and 248 nm laser pulses

Arrays of nanostructures are made starting with a template of close-packed, polystyrene spheres on a silicon surface. The spheres are either 1.091 or 2.99?μm in diameter (d) and are of polystyrene (PS). They are irradiated with a pulse of either 308 or 248?nm light to which they are transparent and semitransparent, respectively. A transparent sphere with d = 1.091?μm diameter concentrates incident light onto a small substrate area. As has been previously reported, that creates silicon nanobumps that rise from circular craters. At 248?nm and d = 2.99?μm, the light energy is mainly absorbed, destroys the sphere, and leaves a shrunken mass (typically about 500?nm wide and 100?nm high) of organic material that is probably polystyrene and its thermal degradation products. At 248?nm and d = 1.091?μm, the residual organic structures are on the order of 300?nm wide and 100?nm high. A distinctive feature is that these organic structures are connected by filaments that are on the order of 50?nm wide and 10?nm high. Filaments form because the close-packed PS spheres expand into each other during the early part of the laser pulse, and then, as the main structures shrink, their viscoelasticity leads to threads between them. Our results with 248?nm and d = 1.091?μm differ from those described by Huang et al with 248?nm and d = 1.0?μm. Future studies might include the further effect of wavelength and fluence upon the process as well the use of other materials and the replacement of nanospheres by other focusing shapes, such as ellipsoids or rods.