Possible Lattice Distortions in the Hubbard Model for Graphene

The Hubbard model on the honeycomb lattice is a well known model for graphene. Equally well known is the Peierls type of instability of the lattice bond lengths. In the context of these two approximations we ask and answer the question of the possible lattice distortions for graphene in zero magnetic field. The answer is that in the thermodynamic limit only periodic, reflection-symmetric distortions are allowed and these have at most six atoms per unit cell as compared to two atoms for the undistorted lattice.Comment: 5 pages, 3 figure

Study of low gravity propellant transfer Quarterly progress report, 23 Dec. 1970 - 30 Apr. 1971

Bellows, metallic diaphragm, and paddle vortex subcritical transfer systems designs and high pressure systems analyses for orbital space station cryogen

A study of the effect of space radiation on silicon integrated circuits, phase 3, volume 2 Final report, 10 Apr. 1967 - 9 Apr. 1968

Characterization plans for studying effect of space radiation on silicon integrated microcircuit

A program to develop a high-energy density primary battery with a minimum of 200 watt hours per pound of total battery weight third quarterly report, jan. - mar. 1965

Electrochemical study of prospective electrode- electrolyte systems for high-energy primary battery with minimum of 200 watt hours per pound of total battery weigh

Most Sub-Arcsecond Companions of Kepler Exoplanet Candidate Host Stars are Gravitationally Bound

Using the known detection limits for high-resolution imaging observations and the statistical properties of true binary and line-of-sight companions, we estimate the binary fraction of {\it Kepler} exoplanet host stars. Our speckle imaging programs at the WIYN 3.5-m and Gemini North 8.1-m telescopes have observed over 600 {\it Kepler} objects of interest (KOIs) and detected 49 stellar companions within $\sim$1 arcsecond. Assuming binary stars follow a log-normal period distribution for an effective temperature range of 3,000 to 10,000 K, then the model predicts that the vast majority of detected sub-arcsecond companions are long period ($P>50$ years), gravitationally bound companions. In comparing the model predictions to the number of real detections in both observational programs, we conclude that the overall binary fraction of host stars is similar to the 40-50\% rate observed for field stars

Genetic Differentiation Among Three Species of \u3ci\u3eParadosa\u3c/i\u3e (Arachnida: Lycosidae)

Allozymic variation in nine protein producing loci was examined in three species of Pardosa using starch gel electrophoresis. Allozyme frequencies showed a high degree of geographic uniformity among conspecific populations. Estimated heterozygosities for the three species ranged from 0.05 to 0.15. Rogers\u27 coefficients of genetic similarity based on allozyme frequencies averaged over conspecific populations ranged from 0.16 to 0.37 fo rthe three species