Partitioning of a polymer chain between a confining cavity and a gel

A lattice field theory approach to the statistical mechanics of charged polymers in electrolyte solutions [S. Tsonchev, R. D. Coalson, and A. Duncan, Phys. Rev. E 60, 4257, (1999)] is applied to the study of a polymer chain contained in a spherical cavity but able to diffuse into a surrounding gel. The distribution of the polymer chain between the cavity and the gel is described by its partition coefficient, which is computed as a function of the number of monomers in the chain, the monomer charge, and the ion concentrations in the solution.Comment: 17 pages, 6 figure

A high resolution millimetre and submillimetre study of W3

The continuum bolometer receiver on the James Clerk Maxwell telescope has been used to map the dense core of the star formation region W3 with a spatial resolution of 15-20 arcsec. At 350 and 800 μm, the region appears as two principal peaks around the known IR sources IRS4 and IRS5, while at 1100 μm, a further peak is noted which is interpreted as being due to free-free emission around IRS2. Taking into account the free-free contribution to the intensity, the continuum dust emission from the region is found to be consistent with optically thin emission at all of the three wavelengths considered. Values for the dust optical depth, hydrogen column density, mass, and central density have been obtained for each of the main peaks

Low-cycle fatigue evaluation for regeneratively cooled panels

Design data for regeneratively cooled panels from low cycle fatigue evaluation of Hastelloy X and Inconel 625 sheet and sandwich panel specimen

IMPACTS OF THE FEDERAL AGRICULTURAL IMPROVEMENT AND REFORM ACT OF 1996 (FAIR ACT) ON THE NORTH DAKOTA AGRICULTURAL ECONOMY

The Federal Agriculture Improvement and Reform Act of 1996 (FAIR Act) decouples government farm subsidy payments from both price and production and provides farmers with nearly complete planting flexibility. Government spending under this act will be limited to $35.63 billion for 1996-2002 period. The net farm income for all six representative farms under the 1996 FAIR Act is projected to be higher than under the 1990 farm act early in the forecast period and lower after 1999 under the 1996 FAIR Act. Cropland prices are projected to fall 19.8% between 1996 and 2002 under the 1996 FAIR Act, while cropland prices are projected to fall 18.5% under the 1990 farm act. Cash rental rates are projected to follow cropland prices. Debt-to-asset ratios for most farms, although rising across the forecast period, do not reach levels that imperil credit- worthiness, but in the case of the low profit farm and small size farm the debt-to-asset ratios rise to a level that may imperil credit-worthiness on new borrowing. Note: Figures are not included in the machine readable file--contact the authors for copies.FAIR Act, net farm income, debt-to-asset ratio, cropland prices, land rental rates, farm operating expenses, capitalization rate, Agricultural and Food Policy,

Impacts of Alternative Farm Programs on the North Dakota Agricultural Economy

Agricultural and Food Policy,

Resolving Exceptional Configurations

In lattice QCD with Wilson fermions, exceptional configurations arise in the quenched approximation at small quark mass. The origin of these large previously uncontrolled lattice artifacts is identified. A simple well-defined procedure (MQA) is presented which removes the artifacts while preserving the correct continuum limit.Comment: Talk presented by E. Eichten at Lattice 97, Edinburgh(UK), July97. 6 pages, LaTeX, 1 table, 5 figure

Furnace and support equipment for space processing

A core facility capable of performing a majority of materials processing experiments is discussed. Experiment classes are described, the needs peculiar to each experiment type are outlined, and projected facility requirements to perform the experiments are treated. Control equipment (automatic control) and variations of the Czochralski method for use in space are discussed

Quantum optical signal processing in diamond

Controlling the properties of single photons is essential for a wide array of emerging optical quantum technologies spanning quantum sensing, quantum computing, and quantum communications. Essential components for these technologies include single photon sources, quantum memories, waveguides, and detectors. The ideal spectral operating parameters (wavelength and bandwidth) of these components are rarely similar; thus, frequency conversion and spectral control are key enabling steps for component hybridization. Here we perform signal processing of single photons by coherently manipulating their spectra via a modified quantum memory. We store 723.5 nm photons, with 4.1 nm bandwidth, in a room-temperature diamond crystal; upon retrieval we demonstrate centre frequency tunability over 4.2 times the input bandwidth, and bandwidth modulation between 0.5 to 1.9 times the input bandwidth. Our results demonstrate the potential for diamond, and Raman memories in general, to be an integrated platform for photon storage and spectral conversion.Comment: 6 pages, 4 figure

Collapse of a Circular Loop of Cosmic String

We study the collapse of a circular loop of cosmic string. The gravitational field of the string is treated using the weak field approximation. The gravitational radiation from the loop is evaluated numerically. The memtric of the loop near the point of collapse is found analytically.Comment: 15 page