Transitions to Nematic states in homogeneous suspensions of high aspect ratio magnetic rods

Isotropic-Nematic and Nematic-Nematic transitions from a homogeneous base state of a suspension of high aspect ratio, rod-like magnetic particles are studied for both Maier-Saupe and the Onsager excluded volume potentials. A combination of classical linear stability and asymptotic analyses provides insight into possible nematic states emanating from both the isotropic and nematic non-polarized equilibrium states. Local analytical results close to critical points in conjunction with global numerical results (Bhandar, 2002) yields a unified picture of the bifurcation diagram and provides a convenient base state to study effects of external orienting fields.Comment: 3 Figure

How Much Do Consumers Benefit from New Brand Introductions? The Case of Potato Chips

This study identifies consumer welfare from new brand introductions in the potato chip market. Price and variety effects of new brand introduction are measured by estimating a demand system underlying an expenditure function. Variety effects are positive in most cities, while price effects are generally negative when consumers exhibit some variety preference. Variety effects dominate price effects in most cities; an opposite effect observed in some cities may indicate high entry barriers or joint brand- and price-based marketing strategies. Results indicate that consumers and producers gain from product innovations, but substantial regional variation exists in the distributional effects of new brand introduction.city-demand system, compensating variation, consumer welfare, new brands, virtual prices, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

Simulation of GaAs p-i-n diodes

GaAs p-i-n diodes have been modeled using numerical simulation, and the theoretical results have been compared to those of experiment. The simulations predict that with a lifetime of the carriers of 10^(-7)s, devices that have good i-layer modulation may be built. This is in agreement with currently available commercial devices

Phase relations associated with mathematical sciences

An analysis of quantitative data on the incidence of phase relations associated with mathematical sciences is presented. It has been found that application and bias phase relations have high percentage of incidence. Physical sciences show a greater tendency for phase relations wittr mathematics. It is also observed that intra-subject phase relations with mathematics is fairly frequent

Acoustic Streaming and Heat and Mass Transfer Enhancement

A second order effect associated with high intensity sound field, acoustic streaming has been historically investigated to gain a fundamental understanding of its controlling mechanisms and to apply it to practical aspects of heat and mass transfer enhancement. The objectives of this new research project are to utilize a unique experimental technique implementing ultrasonic standing waves in closed cavities to study the details of the generation of the steady-state convective streaming flows and of their interaction with the boundary of ultrasonically levitated near-spherical solid objects. The goals are to further extend the existing theoretical studies of streaming flows and sample interactions to higher streaming Reynolds number values, for larger sample size relative to the wavelength, and for a Prandtl and Nusselt numbers parameter range characteristic of both gaseous and liquid host media. Experimental studies will be conducted in support to the theoretical developments, and the crucial impact of microgravity will be to allow the neglect of natural thermal buoyancy. The direct application to heat and mass transfer in the absence of gravity will be emphasized in order to investigate a space-based experiment, but both existing and novel ground-based scientific and technological relevance will also be pursued

Planning of Library and Documentation Systems : a model plan for central and regional units of a system

The generation and diffusion of knowledge, the need for a fast pace and exhaustiveness in information transfer, evolution and functions of modern documentation systems a rediscussed. The need for planning, the steps in planning, and the advantages of planning of a library and documentation system a rebriefly mentioned. A draft model for a 3-phase 15 year developmental plan for a Library and Technical Information System consisting of Central and Regional units is presented. The plan presents the factors affecting library planning, the steps at which information i s needed i n product development, and the sources for information. The structure, organisation, documentation services, personnel, annual budget, and furniture and equipment of the Central Unit a rediscussed in brief. Two models for regional units are given. A list of select reading of 46 documents is also include

Running and tumbling with E. coli in polymeric solutions

Run-and-tumble motility is widely used by swimming microorganisms including numerous prokaryotic eukaryotic organisms. Here, we experimentally investigate the run-and-tumble dynamics of the bacterium E. coli in polymeric solutions. We find that even small amounts of polymer in solution can drastically change E. coli dynamics: cells tumble less and their velocity increases, leading to an enhancement in cell translational diffusion and a sudden decline in rotational diffusion. We show that suppression of tumbling is due to fluid viscosity while the enhancement in swimming speed is mainly due to fluid elasticity. Visualization of single fluorescently labeled DNA polymers reveals that the flow generated by individual E. coli is sufficiently strong to stretch polymer molecules and induce elastic stresses in the fluid, which in turn can act on the cell in such a way to enhance its transport. Our results show that the transport and spread of chemotactic cells can be independently modified and controlled by the fluid material properties