DLC Thin Films and Carbon Nanocomposite Growth by Thermionic Vacuum Arc (TVA) Technology

The aim of this chapter is to report the results on synthesis DLC thin films and carbon nanocomposites by the versatile nanofabrication method based on plasma entitled thermionic vacuum Arc (TVA). TVA technology is based on the localized ignition of the arc plasma in vacuum conditions. Among thin film coating methods by vacuum deposition techniques with high purity, low roughness, and good adhesion on the substrates, TVA is one of the major suitable methods to become a powerful coating technology. Two or three different TVA discharges can be ignited simultaneously in the same chamber for multi-material processing using TVA and separate power supplies. These TVA discharges are localized and do not interfere with each other. Simultaneous two or three TVA discharges were already used for the production of alloy/composite of various materials. This is due to the high versatility concerning the configuration of experimental arrangements, taking into account the number of electron guns, symmetry of the electrodes, relative position of the anode versus cathode, and also the huge opportunity to combine the materials to be deposited: bi- and multi-layers, nanocomposites, or alloys in order to have specific applications. This chapter presents the comparative results concerning the surface-free energy information processing, the reflective index, the hardness, and the morphology to provide a coherent description of the diamond-like carbon films and carbon nanocomposites synthesized by thermionic vacuum arc (TVA) and related configurations where Me = Ag, Al, Cu, Ni, and Ti: binary composites (C-Me, C-Si) and ternary composites (C+Si+Me). The results include reports on the distribution in size, surface, geometry, and dispersion of the nanosized constituents, tailoring and understanding the role of interfaces between structurally or chemically dissimilar phases on bulk properties, as well as the study of physical properties of nanocomposites (structural, chemical, mechanical, tribological). The results presented here could have a great impact on the development of advanced materials and many manufacturing industries, as well as expanding the technologically important field of interface science where the control of the film-substrate interface would be critical

FUEL CELL PROTON EXCHANGE MEMBRANE - PRESENT AND PERSPECTIVES

The fuel cells could contribute to the reduction of the pollution emission and the fossil fuels due to the conversion efficiency which is higher than the other energy conversion systems. There are many possibilities to improve the efficiency and to reduce the weight of the fuel cells by the integration of new nanostructured materials

Synthesis and characterization of some carbon based nanostructures

The aim of present paper is to present the latest results on investigations of the carbon thin film deposited by Thermionic Vacuum Arc (TVA) method and laser pyrolysis. X-ray photoelectron spectroscopy (XPS) and X-ray generated Auger electron spectroscopy (XAES) were used to determine composition and sp2 to sp3 ratios in the outer layers of the film surfaces. The analyses were conducted in a Thermoelectron ESCALAB 250 electron spectrometer equipped with a hemispherical sector energy analyser. Monochromated Al K X-radiation was employed for the XPS examination, at source excitation energy of 15 KeV and emission current of 20 mA. Analyzer pass energy of 20 eV with step size of 0.1 eV and dwell time of 100 ms was used throughout

Broomrape (Orobanche cumana wallr.) control, by developing genetic resistant genotypes in sunflower

Sunflower broomrape (Orobanche cumana Wallr.) is a parasitic plant which has a significant negative impact on seed yield. The parasite is spread in large areas of Europe, Asia and it has identified recently, in North Africa. Breeding for resistance is regarded as the most effective, feasible and environmentally friendly solution to control sunflower broomrape. However, breeding for resistance is challenging as new races of the parasite have evolved. The use of resistant hybrids of monogenic resistance type, is followed by the appearance of new more virulent races that overcome the existing resistance genes. So, it is necessary to develop sunflower hybrids which can accumulate qualitative and quantitative resistance in a single one, in order to have a durable resistance. Among this, by developing Clearfield Production System in sunflower it could have an important control strategy and complemented the genetic resistance against the parasite

The evolution of some pathogens and broomrape parasite attack and virulence, in sunflower crop, in Dobrogea area, Romania

Sunflower diseases represent one of the most serious constraints in sunflower crop in Romania. Dobrogea region has around 24% of the area cultivated with sunflower in Romania. The pathogens attack is frequently severe and yield losses can reach up to 50 – 70 %. In the last years, climate change has an influence on the development of the pathogens, also on the host/pathogens interaction. Some changes occur between pathogenic races, some pathogens increase their attack, according with their thermal preferences Our studies have demonstrated that some of the most important pathogens in sunflower have changed their behavior in different climatic conditions. Some pathogens (Macrophomina phaseolina, Puccinia helianthi) which in the past did not attack too much this crop, in Romania, are present in some cultivated areas with sunflower, in Dobrogea, in the last three years. Also, the pathogen Plasmopara halstedii has developed more virulent races, during the last period. The parasite broomrape (Orobanche cumana Wallr.) has also developed new and more virulent races, comparing with those present four years ago, especially in Constanta area

Sunflower genotypes with high tolerance to drought and extreme temperatures, having good resistance to some specific diseases

Sunflower is considered to be moderately resistant to drought, but in hot conditions, the plants suffer reduction in fertility, yield performance and quality of products. In literature there are mentioned some adoptive mechanisms of plants to drought: escape, avoidance and tolerance, as well as their genetic variability. For sunflower it is very important to increase the cold resistance in early development stages, at stage of germination, emergence and the stage of 2-3 leaves, in order to facilitate an early sowing. Wild Helianthus species are a very valuable source of resistance in increasing drought resistance as well as resistance to low temperatures in sunflower. Some of our best elite lines have been introduced in a process of improvement of resistance to drought, using recurrent selection. Also it has been transfered some genes for controling the attack of some important pathogenes. In this process of selection, we obtained inbred lines (CMS and pollen fertility restorer lines) having very good tolerance to drought as well as resistance to low temperatures

RM-BDP: Resource management for Big Data platforms

International audienceNowadays, when we face with numerous data, when data cannot be classified into regular relational databases and new solutions are required, and when data are generated and processed rapidly, we need powerful platforms and infrastructure as support. Extracting valuable information from raw data is especially difficult considering the velocity of growing data from year to year and the fact that 80% of data is unstructured. In addition, data sources are heterogeneous (various sensors, users with different profiles, etc.) and are located in different situations or contexts. Cloud computing, which concerns large-scale interconnected systems with the main purpose of aggregation and efficient exploiting the power of widely distributed resources, represent one viable solution. Resource management and task scheduling play an essential role, in cases where one is concerned with optimized use of resources (Negru et al., 2017) [1].The goal of this special issue is to explore new directions and approaches for reasoning about advanced resource management and task scheduling methods and algorithms for Big Data platforms. The accepted papers present new results in the domain of resource management and task scheduling, Cloud platforms supporting Big Data processing, data handling and Big Data applications

Polyhedral potential field constructions for obstacle avoidance in a receding horizon formulation

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