Thickness Dependent Structural, Magnetic and Transport Properties of of Cu / Co Thin Film and Multilayer Structures

Structural, magnetic and transport properties of electron beam evaporated Co/Cu thin film and multilayer structures (MLS) having different layer thicknesses have been characterized using XRD, MOKE and resistivity techniques. The structural studies show different crystal structures for different sub-layer thicknesses. The Co (300 Ǻ) single layer film is amorphous, while Cu (300 Ǻ) film is microcrystalline in nature. The particle size is found to decrease as the number of interfaces increase. The corresponding magnetic and resistivity measurements show an increase in saturation field and resistivity. However, coercivity decreases with decrease in particle size. The results conclude that these properties are greatly influenced by various micro structural parameters such as layer thickness, number of bilayers and the quality of interfaces formed under different growth conditions

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Nanoscale roughness and morphology affect the IsoElectric Point of titania surfaces

We report on the systematic investigation of the role of surface nanoscale roughness and morphology on the charging behaviour of nanostructured titania (TiO2) surfaces in aqueous solutions. IsoElectric Points (IEPs) of surfaces have been characterized by direct measurement of the electrostatic double layer interactions between titania surfaces and the micrometer-sized spherical silica probe of an atomic force microscope in NaCl aqueous electrolyte. The use of a colloidal probe provides well-defined interaction geometry and allows effectively probing the overall effect of nanoscale morphology. By using supersonic cluster beam deposition to fabricate nanostructured titania films, we achieved a quantitative control over the surface morphological parameters. We performed a systematical exploration of the electrical double layer properties in different interaction regimes characterized by different ratios of characteristic nanometric lengths of the system: the surface rms roughness Rq, the correlation length {\xi} and the Debye length {\lambda}D. We observed a remarkable reduction by several pH units of IEP on rough nanostructured surfaces, with respect to flat crystalline rutile TiO2. In order to explain the observed behavior of IEP, we consider the roughness-induced self-overlap of the electrical double layers as a potential source of deviation from the trend expected for flat surfaces.Comment: 63 pages, including 7 figures and Supporting Informatio

Spin-String Interaction in QCD Strings

I consider the question of the interaction between a QCD string and the spin of a quark or an antiquark on whose worldline the string terminates. The problem is analysed from the point of view of a string representation for the expectation value of a Wilson loop for a spin-half particle. A string representation of the super Wilson loop is obtained starting from an effective string representation of a Wilson Loop. The action obtained in this manner is invariant under a worldline supersymmetry and has a boundary term which contains the spin-string interaction. For rectangular loops the spin-string interaction vanishes and there is no spin-spin term in the resulting heavy quark potential. On the other hand if an allowance is made for the finite intrinsic thickness of the flux-tube, by assuming that the spin-string interaction takes place not just at the boundary of the string world-sheet but extends to a distance of the order of the intrinsic thickness of the flux tube, then we do obtain a spin-spin interaction which falls as the fifth power of the distance. Such a term was previously suggested by Kogut and Parisi in the context of a flux-tube model of confinement.Comment: 19 pages, 1 figure; Published version with added discussion and references in section

Packing Density Approach for Sustainable Development of Concrete

This paper deals with the details of optimized mix design for normal strength concrete using particle packing density method. Also the concrete mixes were designed as per BIS: 10262-2009. Different water-cement ratios were used and kept same in both design methods. An attempt has been made to obtain sustainable and cost effective concrete product by use of particle packing density method. The parameters such as workability, compressive strength, cost analysis and carbon di oxide emission were discussed. The results of the study showed that, the compressive strength of the concrete produced by packing density method are closer to that of design compressive strength of BIS code method. By adopting the packing density method for design of concrete mixes, resulted in 11% cost saving with 12% reduction in carbon di oxide emission

Cost Effective Design of Sustainable Concrete Using Marble Waste as Coarse Aggregate

In the present study attempts have been made to obtain sustainable and cost effective concrete product by use of marble waste. Aggregate obtained from marble quarry waste was used as 75% part of coarse aggregate and rest was conventional coarse aggregate. It was observed that, compressive strength was almost same as that of the control concrete. Durability properties like permeability and chloride ion penetration improved by approximately 30% and 15%, respectively. Resistance to acids and carbonation were least affected. Cost comparison showed with 24% less cement requirement, 14% reduction in cost of concrete was achieved when marble waste was used with packing density approach for design of concrete mixes. By minimizing the cement content without losing mechanical and durability properties of concrete resulting in reduction of global cement production from 4.2 billion tons to 1.01 billion tons and correspondingly it reduces CO2 emission from 3.95 billion tons by 3.02 billion tons

Classical solutions for Yang-Mills-Chern-Simons field coupled to an external source

We find wide class of exact solutions of Yang-Mills-Chern-Simons theory coupled to an external source, in terms of doubly periodic Jacobi elliptic functions. The obtained solutions include localized solitons, trigonometric solutions, pure cnoidal waves, and singular solutions in certain parameter range. Furthermore, it is observed that these solutions exist over a nonzero background.Comment: 5 page

Organizational Probes:Exploring Playful Interactions in Work Environment

Playfulness, with non-intrusive elements, can be considered a useful resource for enhancing social awareness and community building within work organizations. Taking inspirations from the cultural probes approach, we developed organizational probes as a set of investigation tools that could provide useful information about employees’ everyday playful experiences within their work organizations. In an academic work environment, we applied our organizational probes over a period of three weeks. Based on the collected data we developed two design concepts for playful technologies in work environments

Electrical and Structural Analysis of CNT-Metal Contacts in Via Interconnects

Vertically aligned carbon nanotubes grown by plasmaenhanced chemical vapor deposition offer a potentially suitable material for via interconnects in next-generation integrated circuits. Key performance-limiting factors include high contact resistance and low carbon nanotube packing density, which fall short of meeting the requirements delineated in the ITRS roadmap for interconnects. For individual carbon nanotube s, contact resistance is a major performance hurdle since it is the dominant component of carbon nanotube interconnect resistance, even in the case of vertically aligned carbon nanotube arrays. In this study, we correlate the carbon nanotube-metal interface nanostructure to their electrical properties in order to elucidate growth parameters that can lead to high density and low contact resistance and resistivity

Aortic arch tortuosity with PHACE syndrome : a rare case scenario

PHACE syndrome is a rare neurocutaneous disorder characterised by an association of infantile haemangiomas with structural anomalies of brain, cerebral vasculature, eye, aorta and chest wall.1 Coarctation of aorta (COA) is most the common cardiac anomaly reported in PHACE syndrome. COA or interrupted aortic arch in PHACE is unique and complex both in location and character compared to the typical coarctation anatomy. Arterial tortuosity of the cerebral vasculature has been well described in literature in PHACE syndrome. We present a rare case of tortuous aortic arch continuing as descending aorta in an infant with PHACE syndrome.peer-reviewe