Study of Compacting Methods for Nanostructured Thermoelectric Materials Based on Si-Ge and Half -Heusler Alloys

Recent methods of compacting nanopowders of thermoelectric materials of silicon germanium and Half-Heusler (HH) compounds based on Ni(Ti,Zr,Hf)Sn are presented. Half-Heusler alloys are known to be intermetallic compounds with quite large Seebeck coefficient and semiconducting transport properties. This makes them a potential candidate for thermoelectric applications. In this study we compare compacting methods applied to raw materials as a function of crystal structure. The results suggest that the thermal conductivity can be reduced by increasing the phonon scattering via nanostructuring. The effect of spark plasma sintering (SPS) and hot pressing on Gleeble system was analyzed by TEM and SEM methods. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3551

Thermoelectric Properties of Si-Ge Nanostructured Thermoelectric Materials Synthesized by Mechanical Alloying

Silicon-germanium alloys is one of the best thermoelectric materials in power generation devices operating in 600-1000 C range in heat conversion into electricity directly. The enhancement of efficiency comes mainly from a significant reduction in the thermal conductivity caused by the enhanced phonon scattering off the increased density of nanograin boundaries. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3551

Is there a barrier for the C2v insertion reaction in O(1D)+H2? A test dynamics study based on two-valued energy-switching potential energy surfaces

We have calculated cross-sections and rate constants for the title reaction by using the quasiclassical trajectory method and a recently reported two-valued energy-switching potential energy surface for the water molecule. By varying the amplitude and rate of decay of a local Gaussian term which controls the appearance of a barrier along the C2v minimum energy profile, an attempt has been made to answer the title issue. A comparison of the calculated rate constants with the available experimental data suggests that the barrier, if existing, lies below the energy of the reactants, and separates the small van der Waals well from the deep chemical one at short distances.http://www.sciencedirect.com/science/article/B6TFN-41TMMMJ-14/1/5387db0b34a596a8a15db1e03063755

Model for Assessing the Asymmetry of a Pigmented Neoplasm

Abstract The paper presents the results of the development of a method for recognizing skin neoplasms based on a model for assessing the asymmetry of the shape of the pigment area of the pathological growth of the epidermis and (or) dermis. Images of pigmented skin neoplasms obtained using a dermatoscope were considered as initial data. To analyze the images, a model was used to calculate the shape asymmetry coefficients obtained relative to the main axes of inertia of the neoplasm, which makes it possible to obtain values independent of the angle of rotation of the images

Image Segmentation of Skin Neoplasms Using the Active Contour Method

Abstract Computer vision technologies are being actively introduced into modern life, including medical practice. The development of such technologies has led to the emergence of computer systems that allow the detection and classification of skin diseases with a quality comparable to and in some cases exceeding human capabilities. The article reveals the method of automatic segmentation on the basis of dermatoscopic images provided by doctors obtained using a digital optical device—a dermatoscope. The main goal of the model being developed is to identify the neoplasm zone and areas of hyperpigmentation on images of skin neoplasms for further integration into medical decision support systems for diagnosing of melanoma. As a result of the work carried out, a software package was created that allows segmentation of the neoplasm. As a demonstration of the method, experimental studies of the detection of melanoma boundaries and zones of areas of signs on images of skin neoplasms are presented. The developed system can be used for diagnostic research and educational purposes