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Carbon nanotubes (CNTs) exhibit excellent mechanical and thermal properties. Designing composites that employ CNTs as the reinforcing or filler material offer the potential to create bulk materials with greatly enhanced mechanical and thermal properties. Unfortunately, the resulting property enhancement in CNT, and other carbon nanomaterial, enhanced composites vary greatly. In macroscale composites, like carbon fiber/epoxy composites, the large interface area and relatively low surface area to volume ratio of the carbon fiber/epoxy results in excellent transfer of load or thermal energy across the interface, thus allowing the carbon fiber to enhance the mechanical or thermal properties of the composite. In nanocomposites, the high surface area to volume ratio between the reinforcing and matrix materials requires tightly coupled interactions at the interface. Additionally, due to the high surface area to volume ratio of the nanomaterial filler, there is added difficulty in ensuring the reinforcing materials are uniformly dispersed. These two major differences between macroscale and nanoscale composites results in the existing predictive models failing to predict the effective composite properties. To improve the understanding of the roles that interface bonding and the dispersion of the reinforcing material play on the effective properties, we present the results of a detailed experimental study. To study the role of the reinforcing material/matrix interface bonding, we fabricate CNT/polymer composites where the CNTs are functionalized with different functional groups. To study the role of the nanoparticle filler dispersion, we fabricate CNT polymer composites with different dispersing techniques. This work shows that CNT dispersion is critical for fabricating CNT composites with enhanced mechanical properties.

In this review article the author argues that complete presentation of various Spiritual methods can reduce the stress and related mental and physical illnesses like Stress anxiety, depression etc.. Life is neither Possible to overcome safely. Spiritual methods like Prayer, Meditation, Mantra and some epic methods are increasing in Physical and mental health and reducing stress is an important stimulus of human growth and creativity as well an inevitable part of life.

Considered the nature of the change of the morphology of excess carbides in Damascus steel (Wootz), depending on the degree of supercooling of the melt, heat treatment and plastic deformation. Discovered that some of blades Damascus steel has an unusual nature of origin of the excess cementite, which different from the redundant phases of secondary cementite, cementite of ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of separate particles of cementite in Damascus steels lies in the abnormal size of excess carbides having the shape of irregular prisms. Considered three hypotheses for the formation of excess cementite in the form of faceted prismatic of excess carbides. The first hypothesis is based on thermal fission of cementite of a few isolated grains. The second hypothesis is based on the process of fragmentation cementite during deformation to the separate the pieces. The third hypothesis is based on the transformation of metastable cementite in the stable of angular eutectic carbide. It is shown that the angular carbides are formed within the original metastable colony ledeburite, so they are called “eutectic carbide”. It is established that high-purity white cast iron is converted into of Damascus steel during isothermal soaking at the annealing. It was revealed that some of blades Damascus steel ledeburite class do not contain in its microstructure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity of Damascus steel consists entirely of angular eutectic carbides. Believe that Damascus steel refers to non-heat-resistant steel of ledeburite class, which have similar structural characteristics with semi-heat-resistant die steel or heat-resistant high speed steel, differing from them only in the nature of excess carbide phase.

This research purposes to recognize the effect of re-engineering of administrative operations( engistrative ) on strategic performance in Jordanian companies of mining ; and reach the recommendations that aim to increase the necessity of this side to ameliorate the strategic performance level in these companies from the financial sides ; operational and competitive sides , this research also includes recognizing the effect of personal variables ( gender ; age ; years of experience ; administrative level and scientific qualification) on strategic performance ; whereas this research depends on the descriptive analytical curriculum ; using the questionnaire to study the opinions of sample of research that composes 55 persons like an average ( 15.7%) from the society of research. And this research confirms an effect with statical indication ( a< 05.0) for the dimension of re-engineering of the operations ( administrative settlement ; culture of organization and readiness to change ) jointly and separately on strategic performance of mining companies .The results also approved no differences related with statical significance on the significance level ( a > 05) in strategic performance of the mining companies attributed to personal and functional variables ( gender, age ) , The results also approved differences related with statical significance on the significance level ( a > 05) in strategic performance of the mining companies attributed to the variables (scientific qualification , scientific experience and administrative level ) . The research recommended a number of recommendations, the most important; work on the application of the concept of operations re-engineering to increase its ability to ameliorate the strategic performance by supporting creators and motivating them , adopting their ideas , assigning them with works show their intellectual challenges and sharpen their spirit of creation , also encouraging them to be against the familiar from typical specific thinking…