Irreducible completely pointed modules of quantum groups of type AA

We give a classification of all irreducible completely pointed $U_q(\mathfrak{sl}_{n+1})$ modules over a characteristic zero field in which $q$ is not a root of unity. This generalizes the classification result of Benkart, Britten and Lemire in the non quantum case. We also show that any infinite-dimensional irreducible completely pointed $U_q(\mathfrak{sl}_{n+1})$ can be obtained from some irreducible completely pointed module over the quantized Weyl algebra $A_{n+1}^q$.Comment: 25 page

Low temperature electron transfer in strongly condensed phase

Electron transfer coupled to a collective vibronic degree of freedom is studied in strongly condensed phase and at lower temperatures where quantum fluctuations are essential. Based on an exact representation of the reduced density matrix of the electronic+reaction coordinate compound in terms of path integrals, recent findings on the overdamped limit in quantum dissipative systems are employed. This allows to give for the first time a consistent generalization of the well-known Zusman equations to the quantum domain. Detailed conditions for the range of validity are specified. Using the Wigner transform these results are also extended to the quantum dynamics in full phase space. As an important application electronic transfer rates are derived that comprise adiabatic and nonadiabatic processes in the low temperature regime including nuclear tunneling. Accurate agreement with precise quantum Monte Carlo data is observed.Comment: 16 pages, 6 figures, revised version with minor change

Structure of the novel membrane-coating material in proton-secreting epithelial cells and identification as an H+ATPase.

Specialized proton-secreting cells known collectively as mitochondria-rich cells are found in a variety of transporting epithelia, including the kidney collecting duct (intercalated cells) and toad and turtle urinary bladders. These cells contain a population of characteristic tubulovesicles that are believed to be involved in the shuttling of proton pumps (H+ATPase) to and from the plasma membrane. These transporting vesicles have a dense, studlike material coating the cytoplasmic face of their limiting membranes and similar studs are also found beneath parts of the plasma membrane. We have recently shown that this membrane coat does not contain clathrin. The present study was performed to determine the structure of this coat in rapidly frozen and freeze-dried tissue, and to determine whether the coat contains a major membrane protein transported by these vesicles, a proton pumping H+ATPase. The structure of the coat was examined in proton-secreting, mitochondria-rich cells from toad urinary bladder epithelium by rapidly freezing portions of apical membrane and associated cytoplasm that were sheared away from the remainder of the cell using polylysine-coated coverslips. Regions of the underside of these apical membranes as large as 0.2 micron2 were decorated by studlike projections that were arranged into regular hexagonal arrays. Individual studs had a diameter of 9.5 nm and appeared to be composed of multiple subunits arranged around a central depression, possibly representing a channel. The studs had a density of approximately 16,800 per micron2 of membrane. Similar arrays of studs were also found on vesicles trapped in the residual band of cytoplasm that remained attached to the underside of the plasma membrane, but none were seen in adjacent granular cells. To determine whether these arrays of studs contained H+ATPase molecules, we examined a preparation of affinity-purified bovine medullary H+ATPase, using the same technique, after incorporation of the protein eluted from a monoclonal antibody affinity column into phospholipid liposomes. The affinity-purified protein was shown to be capable of ATP-dependent acidification. In such preparations, large paracrystalline arrays of studs identical in appearance to those seen in situ were found. The dimensions of the studs as well as the number per square micrometer of membrane were identical to those of toad bladder mitochondria-rich cells: 9.5 nm in diameter, 16,770 per micron2 of membrane.(ABSTRACT TRUNCATED AT 400 WORDS

Analysis of low temperature trapping and recombination in II-VI compounds using photodielectric techniques

Using photodielectric effect to detect densities of free and trapped carriers in II-VI compounds at cryogenic temperature

Research on digital transducer principles. Volume 6 - The photodielectric effect in cadmium sulfide, 1 July 1967 - 30 June 1968

Cadmium sulfide photodielectric effect at cryogenic temperatures with bibliograph

Experimental Effervescence and Freezing Point Depression Measurements of Nitrogen in Liquid Methane-Ethane Mixtures

NASA is designing an unmanned submarine to explore the depths of the hydrocarbon-rich seas on Saturn's moon Titan. Data from Cassini indicates that the Titan north polar environment sustains stable seas of variable concentrations of ethane, methane, and nitrogen, with a surface temperature near 93 K. The submarine must operate autonomously, study atmosphere/sea exchange, interact with the seabed, hover at the surface or any depth within the sea, and be capable of tolerating variable hydrocarbon compositions. Currently, the main thermal design concern is the effect of effervescence on submarine operation, which affects the ballast system, science instruments, and propellers. Twelve effervescence measurements on various liquid methane-ethane compositions with dissolved gaseous nitrogen are thus presented from 1.5 bar to 4.5 bar at temperatures from 92 K to 96 K to simulate the conditions of the seas. After conducting effervescence measurements, two freezing point depression measurements were conducted. The freezing liquid line was depressed more than 15 K below the triple point temperatures of pure ethane (90.4 K) and pure methane (90.7 K). Experimental effervescence measurements will be used to compare directly with effervescence modeling to determine if changes are required in the design of the thermal management system as well as the propellers

Simplicity and maximal commutative subalgebras of twisted generalized Weyl algebras

In this paper we show that each non-zero ideal of a twisted generalized Weyl algebra (TGWA) $A$ intersects the centralizer of the distinguished subalgebra $R$ in $A$ non-trivially. We also provide a necessary and sufficient condition for the centralizer of $R$ in $A$ to be commutative, and give examples of TGWAs associated to symmetric Cartan matrices satisfying this condition. By imposing a certain finiteness condition on $R$ (weaker than Noetherianity) we are able to make an Ore localization which turns out to be useful when investigating simplicity of the TGWA. Under this mild assumption we obtain necessary and sufficient conditions for the simplicity of TGWAs. We describe how this is related to maximal commutativity of $R$ in $A$ and the (non-) existence of non-trivial $\Z^n$-invariant ideals of $R$. Our result is a generalization of the rank one case, obtained by D. A. Jordan in 1993. We illustrate our theorems by considering some special classes of TGWAs and providing concrete examples.Comment: 32 pages, no figures, minor improvements of the presentation of the materia

Solvent-mediated interactions between nanoparticles at fluid interfaces

We investigate the solvent mediated interactions between nanoparticles adsorbed at a liquid-vapor interface in comparison to the solvent mediated interactions in the bulk liquid and vapor phases of a Lennard-Jones solvent. Molecular dynamics simulation data for the latter are in good agreement with results from integral equations in the reference functional approximation and a simple geometric approximation. Simulation results for the solvent mediated interactions at the interface differ markedly from the interactions of the particles in the corresponding bulk phases. We find that at short interparticle distances the interactions are considerably more repulsive than those in either bulk phase. At long interparticle distances we find evidence for a long-ranged attraction. We discuss these observations in terms of interfacial interactions, namely, the three-phase line tension that would operate at short distances, and capillary wave interactions for longer interparticle distances.Comment: 22 pages, 6 figure