4,053 research outputs found
Phase Separation in Binary Fluid Mixtures with Continuously Ramped Temperature
We consider the demixing of a binary fluid mixture, under gravity, which is
steadily driven into a two phase region by slowly ramping the temperature. We
assume, as a first approximation, that the system remains spatially isothermal,
and examine the interplay of two competing nonlinearities. One of these arises
because the supersaturation is greatest far from the meniscus, creating
inversion of the density which can lead to fluid motion; although isothermal,
this is somewhat like the Benard problem (a single-phase fluid heated from
below). The other is the intrinsic diffusive instability which results either
in nucleation or in spinodal decomposition at large supersaturations.
Experimental results on a simple binary mixture show interesting oscillations
in heat capacity and optical properties for a wide range of ramp parameters. We
argue that these oscillations arise under conditions where both nonlinearities
are important
Textile Design in the Marketplace
INTRODUCTION:As textile historians we are trained to observe physical evidence — materials, structures, methods of applying surface decoration and patterns. In brief, we deal with design. Despite our design focus, we frequently seek to explain differences within the context- of art historical research. Our conclusions, like those of the art historian, often focus on attribution and connoisseurship, rather than contributing to an understanding of textiles as cultural or economic indicators.
Although the academic study of design dates from the mid-19th century, only in recent years has this study moved from considerations of styling. Within the last three decades the critical examination of design objects and processes have given rise to the nascent discipline of design history. Increasingly design is viewed as the material embodiment of social and economic values. It is examined in light of the interrelationships that exist among the design process, marketing, distribution, customer satisfaction, and factors of supply and demand.
In this context, design is viewed as evidence for the complicated means of managing the activities of daily life. Those who use design in effect make choices about technology, aesthetics, function, market trends, even about our notions of progress, when creating the objects and processes for others. The user, in fact, has only two choices: to acquire the product or to reject it.
DESIGN HISTORY MODEL FOR TRADE TEXTILES:The study of trade textiles compels us to consider the marketplace. Regardless of their place in time or the nature of their production, trade textiles embody an economic imperative. They were created as commodities to be bartered or sold. Only after the market transaction occurs, do the actual objects assume meaning through usage or association. Take, for example a seventeenth-century embroidered bed cover made in China for the Spanish market. To the producer the product existed solely for financial gain. To the user, its meaning as a status possession was based on prestige, embodying notions of taste, exotic appeal, cost, rarity. Its meaning as an artifact for the contemporary textile curator is based on age, survival, the history of ownership and technique.
The marketplace is a point of transfer. Transfer is both physical and intellectual; it is based on a contract between buyer and seller. If a contract does not exist, negotiation breaks down and trade does not take place. In some sense this contract is embodied in the bill of sale. Yet, the contract is infinitely more complex. It consists of a number of interrelated factors and influences
Experimental entanglement distribution by separable states
The distribution of entanglement between macroscopically separated parties
represents a crucial protocol for future quantum information networks.
Surprisingly, it has been theoretically shown that two distant systems can be
entangled by sending a third mediating system that is not entangled with either
of them. Such a possibility seems to contradict the intuition that to
distribute entanglement, the transmitted system always needs to be entangled
with the sender. Here, we experimentally distribute entanglement by exchanging
a subsystem and successfully prove that this subsystem is not entangled with
either of the two parties. Our implementation relies on the preparation of a
specific three-mode Gaussian state containing thermal noise that demolishes the
entanglement in two of the three bipartite splittings. After transmission of a
separable mode this noise can be removed by quantum interference. Our work
demonstrates an unexpected variant of entanglement distribution and improves
the understanding necessary to engineer multipartite quantum information
networks.Comment: 9 pages, 6 figure
In situ observation of single-molecule surface reactions from low to high affinities
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordUnderstanding reactions occurring between ligand molecules and nanomaterial surfaces is essential in the field of nanoscience. The conventional methods for characterizing
such surface-based reactions allow only for the analysis of the end product of a reaction,
although the reaction path proceeds through the transient interaction of reactants and
with kinetics dependent on environmental parameters. Here we study single molecule
reaction kinetics associated with gold nanoparticle surfaces in an aqueous medium by
utilizing whispering-gallery-mode microcavity sensors. Our approach resolves transient
as well as permanent interaction kinetics of ligand molecules at the nanoparticle interface in situ, over a broad range of affinities and even under conditions where no net
product is formed. This enables us to monitor and characterize reactions during the
entire procedure of a bottom-up surface modification, ranging from the deposition of
ligands to the confirmation of their functionality. We demonstrate this prospect by
studying surface reaction kinetics with respect to the species of ligand head groups,
tethered molecules, and inhibitors in addition to subsequent bio-specific reactions between tethered molecules and analytes.Max Planck Societ
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