Electrooptic polymer voltage sensor and method of manufacture thereof

An optical voltage sensor utilizing an electrooptic polymer is disclosed for application to electric power distribution systems. The sensor, which can be manufactured at low cost in accordance with a disclosed method, measures voltages across a greater range than prior art sensors. The electrooptic polymer, which replaces the optical crystal used in prior art sensors, is sandwiched directly between two high voltage electrodes. Voltage is measured by fiber optical means, and no voltage division is required. The sample of electrooptic polymer is fabricated in a special mold and later mounted in a sensor housing. Alternatively, mold and sensor housing may be identical. The sensor housing is made out of a machinable polymeric material and is equipped with two opposing optical windows. The optical windows are mounted in the bottom of machined holes in the wall of the mold. These holes provide for mounting of the polarizing optical components and for mounting of the fiber optic connectors. One connecting fiber is equipped with a light emitting diode as a light source. Another connecting fiber is equipped with a photodiode as a detector

The Minnie, or, The war cruise of the U.S.S. Minneapolis

From the Prologue The Minnie is truly a veteran. Only a very few other fighting ships in Uncle Sam\u27s Navy have more battle stars than the Minneapolis. During one twenty-month cruise in the Pacific she covered a distance equivalent to nearly seven times around the world. She was in port only eight days during this period which netted each crewman 48 hours of leave. The Minneapolis has served with the Third, Fifth and Seventh Fleets and in all types of operations. Many times the crew could not help but believe that the old ship was classed as expendable, as whenever there was a job to do, the Minnie seemed to be assigned to help do it. Censorship kept her name out of the hometown papers because she was always in action. It has been said the ships that get the publicity are the ones that get sunk, but the Nips couldn\u27t sink the Minnie although they tried time after time.https://digicom.bpl.lib.me.us/ww_reg_his/1147/thumbnail.jp

Z2=0\mathbb{Z}_{2}=0 is topological too

The electronic ground state of a three-dimensional (3D) band insulator with time-reversal ($\Theta$) symmetry or time-reversal times a discrete translation ($\Theta T_{1/2}$) symmetry is classified by a $\mathbb{Z}_{2}$-valued topological invariant and characterized by quantized magnetoelectric response. Here we demonstrate by explicit calculation in model $\mathbb{Z}_{2}$ topological insulator thin-films that whereas the magnetoelectric response is localized at the surface in the $\Theta$ symmetry (non-magnetic) case, it is non-universally partitioned between surface and interior contributions in the $\Theta T_{1/2}$ (anti-ferromagnetic) case, while remaining quantized. Within our model the magnetic field induced polarization arises entirely from an anomalous ${\cal N}=0$ Landau level subspace within which the projected Hamiltonian is a generalized Su-Schrieffer-Heeger model whose topological properties are consistent with those of the starting 3D model.Comment: 6+13 pages, 4 figures, comments welcom

Reconciling magnetoelectric response and time-reversal symmetry in non-magnetic Z2\mathbb{Z}_2 topological insulators

A delicate tension complicates the relationship between the topological magnetoelectric effect in three-dimensional $\mathbb{Z}_2$ topological insulators (TIs) and time-reversal symmetry (TRS). TRS underlies a particular $\mathbb{Z}_2$ topological classification of the electronic ground state of a bulk insulator and the associated quantization of the magnetoelectric coefficient calculated using linear response theory, but according to standard symmetry arguments simultaneously forbids any physically meaningful magnetoelectric response. This tension between theories of magnetoelectric response in bulk and finite-sized materials originates from the distinct approaches required to introduce notions of polarization and orbital magnetization in those fundamentally different environments. In this work we argue for a modified interpretation of the bulk linear response calculations in non-magnetic TIs that is more plainly consistent with TRS, and use this interpretation to discuss the effect's observation - still absent over a decade after its prediction. Our analysis is reinforced by microscopic bulk and thin film calculations carried out using a simplified but still realistic model for the well established V$_2$VI$_3$ (V $=$ (Sb,Bi) and VI $=$ (Se,Te)) family of non-magnetic $\mathbb{Z}_2$ TIs. We conclude that the topological magnetoelectric effect in non-magnetic $\mathbb{Z}_2$ TIs is activated by magnetic surface dopants, and that the charge density response to magnetic fields and the orbital magnetization response to electric fields in a given sample are controlled in part by the configuration of those dopants.Comment: 30 pages, 5 figure

Poor electronic screening in lightly doped Mott insulators observed with scanning tunneling microscopy

The effective Mott gap measured by scanning tunneling microscopy (STM) in the lightly doped Mott insulator $(\rm{Sr}_{1 -x}\rm{La}_x)_2\rm{IrO}_4$ differs greatly from values reported by photoemission and optical experiments. Here, we show that this is a consequence of the poor electronic screening of the tip-induced electric field in this material. Such effects are well known from STM experiments on semiconductors, and go under the name of tip-induced band bending (TIBB). We show that this phenomenon also exists in the lightly doped Mott insulator $(\rm{Sr}_{1 -x}\rm{La}_x)_2\rm{IrO}_4$ and that, at doping concentrations of $x\leq 4 \%$, it causes the measured energy gap in the sample density of states to be bigger than the one measured with other techniques. We develop a model able to retrieve the intrinsic energy gap leading to a value which is in rough agreement with other experiments, bridging the apparent contradiction. At doping $x \approx 5 \%$ we further observe circular features in the conductance layers that point to the emergence of a significant density of free carriers in this doping range, and to the presence of a small concentration of donor atoms. We illustrate the importance of considering the presence of TIBB when doing STM experiments on correlated-electron systems and discuss the similarities and differences between STM measurements on semiconductors and lightly doped Mott insulators.Comment: 9 pages, 5 figure

Organometallic mediated radical polymerization

Controlled radical polymerization has become increasingly important over the past decade and a half, allowing for the facile synthesis of specific macromolecular architectures with excellent control over the chemical and physical properties. This article presents an organized and detailed review of one particular CRP technique, organometallic mediated radical polymerization (OMRP), focusing on the individual catalysts developed, their efficacy and monomer scope. Rhodium, cobalt, molybdenum, osmium, iron, palladium, titanium, chromium and vanadium mediated radical polymerizations are presented alongside organo-main group mediated reactions. A separate section reviews the types of copolymers which have been synthesized using OMRP techniques. An attempt is made to unify the many disparate names which have previously been used for OMRP by virtue of the common mechanistic aspects displayed by the different catalyst systems. A mechanistic discussion highlights the similarities and differences between these systems and examines the interplay between reversible termination and degenerative transfer OMRP and competing 1-electron redox processes

Gathering Good Corn from the Weeds: Theological and Pastoral Engagements with the Prickynge of Love in Post-Reformation England

This essay represents a new approach to the highly conflicted responses of scholars from the period of the English Reformation to medieval religious literature. Recent studies of sixteenth-century antiquarian engagements with medieval literature have thrown much light on the attitudes of bibliophiles like John Leland, John Bale and the circle of antiquarians connected with Archbishop Matthew Parker. However, there has been little detailed documentation of post-Reformation engagements with actual books and of the productive rehabilitation of texts that had become doctrinally problematic in Elizabethan England. This essay analyses the engagements of Stephen Batman and an anonymous ecclesiastical annotator with the Pricking of Love, a deeply affective late fourteenth-century devotional treatise. The medieval text, infused with fervent Christological and Marian piety, is seemingly an unlikely source for reformed Elizabethan readers in which to recognise valuable religious lore. But in fact, these readers go far beyond repudiating ‘papistical’ errors to demonstrate both the past roots of their own reformed theologies and the continuing pastoral utilities of much of the medieval text

Methods for estimating long-distance dispersal

Long-distance dispersal (LDD) includes events in which propagules arrive, but do not necessarily establish, at a site far removed from their origin. Although important in a variety of ecological contexts, the system-specific nature of LDD makes far removed difficult to quantify, partly, but not exclusively, because of inherent uncertainty typically involved with the highly stochastic LDD processes. We critically review the main methods employed in studies of dispersal, in order to facilitate the evaluation of their pertinence to specific aspects of LDD research. Using a novel classification framework, we identify six main methodological groups: biogeographical; Eulerian and Lagrangian movement/redistributional; short-term and long-term genetic analyses; and modeling. We briefly discuss the strengths and weaknesses of the most promising methods available for estimation of LDD, illustrating them with examples from current studies. The rarity of LDD events will continue to make collecting, analyzing, and interpreting the necessary data difficult, and a simple and comprehensive definition of LDD will remain elusive. However, considerable advances have been made in some methodological areas, such as miniaturization of tracking devices, elaboration of stable isotope and genetic analyses, and refinement of mechanistic models. Combinations of methods are increasingly used to provide improved insight on LDD from multiple angles. However, human activities substantially increase the variety of long-distance transport avenues, making the estimation of LDD even more challenging

High-Pressure Neutron-Scattering Studies of Graphite and Stage-Two Graphite-SbCl₅

The longitudinal-acoustic (LA) phonons propagating along the c axis in highly oriented pyrolytic graphite (HOPG) were investigated as a function of pressure up to 20 kbar using inelastic-neutron-scattering techniques. The phonon frequencies varied as (P,q)=A(P)sin[c(P)q/2], where A(P) and c(P) indicate the pressure dependences of the zone-center LO frequency of B1g1 symmetry and of the c-axis lattice spacing, respectively. From the measurements, the mode Grüneisen parameter for the LA branch was estimated to be 1.5 x 10-2 kbar-1 (independent of q); the elastic constant C33 for HOPG was found to be 3.40 x 1011 dyn/cm2 at 1 bar with a pressure coefficient of (1/C33)(dC33/dP)=2.91 x 10-2 kbar-1. The measured c-axis spacings were 6.71 and 12.72 Å for HOPG and stage-2 SbCl5-intercalated graphite, respectively, at atmospheric pressure; the corresponding compressibilities (1/c)(dc/dP) were -2.24 x 10-3 kbar-1 (HOPG) and -2.28 x 10-3 kbar-1 (SbCl5). Elastic-neutron-scattering studies up to 20 kbar were undertaken to search for stage transformations, but no evidence of any phase transition was observed

Scoping market-based opportunities for Indigenous provision of water quality services and associated conservation governance in the Northern Great Barrier Reef: interim report

[Extract] NESP TWQ Hub Project 2.3.3 focuses on scoping water-related ecosystem services (ES) market opportunities and products that are culturally, environmentally, economically, and politically suited to CYP catchments flowing into the northern Great Barrier Reef (GBR). These kinds of ES are often known internationally by terms such as 'nutrient offsets' and 'watershed ES', and the particular focus here is on potential water quality ES (WQES). The project also considers the importance of developing water-oriented services and products that might deliver a range of additional ecosystem services (e.g. biodiversity), cultural and socio-economic benefits. Multiple-benefit products and services have the value of being both more attractive in building Indigenous livelihoods, but also potentially deliver higher market value. The project is a collaboration between researchers at CSIRO and JCU, and staff at local (Kalan Enterprises) and regional Cape York Partnership (CYPS) Indigenous development agencies in CYP. It has been designed to underpin ES-based livelihood opportunities and the realisation of social co-benefits from Indigenous Cultural Resource and Natural Resource Management (ICNRM). This report is effectively a working paper that outlines key developments in the project thus far, and outlines next steps for the second year of the project