A Fly in the Ointment: PROMESA\u27s Drafting Error in Section 314(b)(7)

When Congress amended the Bankruptcy Code in 1984, Congress precluded Puerto Rico from seeking bankruptcy relief under chapter 9. The author explores the history of this exclusion, the case Puerto Rico v. Franklin California Tax-Free Trust, and § 314(b)(7) of the Puerto Rico Oversight Management and Economic Stability Act. The author then concludes that § 314(b)(7) should be removed to resolve the dysfunction it creates

Electrical and structural degradation of GaN high electron mobility transistors under high-power and high-temperature Direct Current stress

We have stressed AlGaN/GaN HEMTs (High Electron Mobility Transistors) under high-power and high-temperature DC conditions that resulted in various levels of device degradation. Following electrical stress, we conducted a well-established three-step wet etching process to remove passivation, gate and ohmic contacts so that the device surface can be examined by SEM and AFM. We have found prominent pits and trenches that have formed under the gate edge on the drain side of the device. The width and depth of the pits under the gate edge correlate with the degree of drain current degradation. In addition, we also found visible erosion under the full extent of the gate. The depth of the eroded region averaged along the gate width under the gate correlated with channel resistance degradation. Both electrical and structural analysis results indicate that device degradation under high-power DC conditions is of a similar nature as in better understood high-voltage OFF-state conditions. The recognition of a unified degradation mechanism provides impetus to the development of a degradation model with lifetime predictive capabilities for a broad range of operating conditions spanning from OFF-state to ON-state.United States. Office of Naval Research.Design-for-Reliability Initiative for Future Technologies. Multidisciplinary University Research Initiative

Extraction of the Spin Glass Correlation Length

The peak of the spin glass relaxation rate, S(t)=d{-M_{TRM}(t,t_w)}/H/{d ln t}, is directly related to the typical value of the free energy barrier which can be explored over experimental time scales. A change in magnetic field H generates an energy E_z={N_s}{X_fc}{H^2} by which the barrier heights are reduced, where X_{fc} is the field cooled susceptibility per spin, and N_s is the number of correlated spins. The shift of the peak of S(t) gives E_z, generating the correlation length, Ksi(t,T), for Cu:Mn 6at.% and CdCr_{1.7}In_{0.3}S_4. Fits to power law dynamics, Ksi(t,T)\propto {t}^{\alpha(T)} and activated dynamics Ksi(t,T) \propto {ln t}^{1/psi} compare well with simulation fits, but possess too small a prefactor for activated dynamics.Comment: 4 pages, 4 figures. Department of Physics, University of California, Riverside, California, and Service de Physique de l'Etat Condense, CEA Saclay, Gif sur Yvette, France. To appear in Phys. Rev. Lett. January 4, 199

Om Uldvaskning. Et Brev til Kammerraad Drewsen.

Om Uldvaskning. Et Brev til Kammerraad Drewsen

Deformation measurements of composite multi-span beam shear specimens by Moire interferometry

Experimental analyses were performed for determination of in plane deformations and shear strains in unidirectional and quasi-isotropic graphite-epoxy beams. Forty-eight ply beams were subjected to 5 point and 3 point flexure. Whole field measurements were recorded at load levels from about 20% to more than 90% of failure loads. Contour maps of U and W displacement fields were obtained by moire interferometry, using reference gratings of 2400 lines/mm. Clearly defined fringes with fringe orders exceeding 1000 were obtained. Whole field contour maps of shear strains were obtained by a method developed for these tests. Various anomalous effects were detected in the displacement fields. Their analysis indicated excess shear strains in resin rich zones in regions of shear tractions; free edge shear strains in quasi-isotropic specimens in regions of normal stresses; and shear stresses associated with cyclic shear compliances of quasi-isotropic plies in regions of shear tractions. Their contributions could occur independently or in superposition. Qualitative analyses addressed questions of relaxation; influence of contact stress distribution; specimen failure; effect of specimen overhang; nonlinearity; and qualities of 5 and 3 point flexure tests

Quantification of Quality Attributes, Functional Compounds, and Antioxidant Capacity of Blackberry and Blackberry Wines

The objective of the study was: (i) investigate two cultivars, Apache and Ouachita, and two growing locations, Central Arkansas and Eastern Oklahoma, in order to determine their possible influences on the quality and antioxidant capacity of whole berries and wine; (ii) measure antioxidant capacity of blackberries at different stage of processing-whole berries, juice, unracked wine, and racked wine; (iii) investigate consumer‟s preference for cultivar and/or growing location and assess the impact of winemaking technique on wine quality and antioxidant capacity. The Folin-Ciocalteu method was used to measure total phenolic contents and the pH differential method was used to evaluate total anthocyanin contents. Oxygen Radical Absorbance Capacity (ORAC) assays were also conducted in order to measure antioxidant activity. Qualitative tests such as pH, tiratable acidity, soluble solids were conducted to measure the quality of blackberry fruit. Sensory tests were also performed on whole berries in order to evaluate subjective impressions of quality. Whole berries had the highest total phenolics, total anthocyanins, and ORAC values, followed by juice and wines respectively. Blackberries rated higher in titratable acidity, pH and soluble solids were more preferred in terms of blackberry flavor. The Apache cultivar was preferred among Oklahoma-grown berries while the Ouachita cultivar was preferred among Arkansas-grown berries. Wine processing technique did not significantly affect the antioxidant capacity of blackberry wines; however, berries pressed after fermentation trended toward higher total phenolics while wines made by fermenting pressed juice were numerically higher in total anthocyanins and ORAC values. Oklahoma-grown berries showed slightly higher values for total phenolics, total anthocyanins, and ORAC values. Total anthocyanin content was strongly correlated with ORAC values in wine while total phenolics content was strongly correlated with ORAC values in whole berries and juice. Blackberry processing byproducts may be a good source of antioxidants given that substantial amounts of antioxidants appear to remain in the blackberry pomace after pressing.Department of Animal Scienc

Aging, rejuvenation, and memory effects in short-range Ising spin glass: Cu0.5_{0.5}Co0.5_{0.5}Cl2_{2}-FeCl3_{3} graphite bi-intercalation compound

Non-equilibrium aging dynamics in 3D Ising spin glass Cu$_{0.5}$Co$_{0.5}$Cl$_{2}$-FeCl$_{3}$ GBIC has been studied by zero-field cooled (ZFC) magnetization and low frequency AC magnetic susceptibility ($f = 0.05$ Hz), where $T_{g} = 3.92 \pm 0.11$ K. The time dependence of the relaxation rate $S(t) = (1/H)$d$M_{ZFC}/$d$\ln t$ for the ZFC magnetization after the ZFC aging protocol, shows a peak at a characteristic time $t_{cr}$ near a wait time $t_{w}$ (aging behavior), corresponding to a crossover from quasi equilibrium dynamics to non-equilibrium. The time $t_{cr}$ strongly depends on $t_{w}$, temperature ($T$), magnetic field ($H$), and the temperature shift ($\Delta T$). The rejuvenation effect is observed in both $\chi^{\prime}$ and $\chi^{\prime\prime}$ under the $T$-shift and $H$-shift procedures. The memory of the specific spin configurations imprinted during the ZFC aging protocol can be recalled when the system is re-heated at a constant heating rate. The aging, rejuvenation, and memory effects observed in the present system are discussed in terms of the scaling concepts derived from numerical studies on 3D Edwards-Anderson spin glass model.Comment: 14 pages, 14 figures; Eur. Phys. J. B accepted for publicatio

Double polarization hysteresis loop induced by the domain pinning by defect dipoles in HoMnO3 epitaxial thin films

We report on antiferroelectriclike double polarization hysteresis loops in multiferroic HoMnO3 thin films below the ferroelectric Curie temperature. This intriguing phenomenon is attributed to the domain pinning by defect dipoles which were introduced unintentionally during film growth process. Electron paramagnetic resonance suggests the existence of Fe1+ defects in thin films and first principles calculations reveal that the defect dipoles would be composed of oxygen vacancy and Fe1+ defect. We discuss migration of charged point defects during film growth process and formation of defect dipoles along ferroelectric polarization direction, based on the site preference of point defects. Due to a high-temperature low-symmetry structure of HoMnO3, aging is not required to form the defect dipoles in contrast to other ferroelectrics (e.g., BaTiO3).Comment: 4 figure