Modelling dielectric and magnetic properties of ferroconcrete

This contribution discusses the modelling and parameterization of dielectric and magnetic properties of ferroconcrete by using numerical electromagnetic field analysis software. The software is based on the Method of Moments (MoM). The shielding effectiveness (SE) of the ferroconcrete DUT was already measured in a study by order of the government. According to these results, the ferroconcrete DUT is modelled and calculated. Therefore the DUT is subdivided into two parts. The first part represents the reinforcement mesh; the second part represents the lossy concrete with complex permittivity. Afterwards, the reflection and transmission properties of numerical analysed building materials are validated and compared with the measurement results in a frequency range of 30-1000 MHz

Cockade breccia: Product of mineralisation along dilational faults

Cockade breccias are a type of fault fills in which individual clasts are completely surrounded by concentric layers of cement. They occur particularly in low-temperature near-surface hydrothermal veins. At least six mechanisms have been proposed for the formation of cockade breccia-like textures, but only two – repeated rotation-accretion, and partial metasomatic replacement of clast minerals – have been supported by detailed evidence. A typical example of cockade breccia from the Gower Peninsula (South Wales) shows clear evidence for the rotation-accretion mechanism: in particular, overgrown breakage points in cement layers – where cockades were previously touching each other – and rotated geopetal infills of haematitic sediment. Based on the available evidence, it is proposed that cockade textures result from low rates of cement growth compared to high rates of dilational fault slip. Seven criteria are given for the correct identification of cockade breccias.This is the author's accepted manuscript and will be under embargo until publication. The final version is available from Elsevier in the Journal of Structural Geology at http://www.sciencedirect.com/science/article/pii/S0191814114001989

Shielding effectiveness of original and modified building materials

This contribution deals with the determination of the shielding effectiveness of building materials used for office, factory and government buildings. Besides the examination of standard materials, measurements were also performed on modified materials, e.g. ferro concrete with enhanced shielding effectiveness due to a changed mixture or structure of the reinforcement. The measurements of original and modified materials were carried out in a fully anechoic room (FAR) according to IEEE 299-1997 from 80 MHz up to 10 GHz

IMPACTO DE LOS PROCESOS DE EVALUACIÓN Y ACREDITACIÓN EN EL ÁMBITO UNIVERSITARIO

La educación superior debe introducir la evaluación institucional en su quehacer habitual, ya sea mediante procesos de autorregulación, mediante evaluaciones externas o ambos. Durante los procesos de evaluación y acreditación, los miembros de la comunidad universitaria se tornan más sensibles de todo cuanto sucede en su entorno. Esto puede convertirse en una oportunidad que debe ser aprovechada por los responsables de la conducción para lograr cambios de hábitos positivos dentro de la comunidad, generar conductas que permitan mejorar tanto el aspecto académico como institucional y corregir aquellos aspectos que resulten perjudiciales para el buen funcionamiento institucional. Como miembros de la comunidad universitaria, masa crítica pensante y autónoma, tenemos la obligación de estar siempre alertos, investigar y debatir las causas y los efectos de las políticas que afectan a nuestra Institución. En este trabajo analizaremos los impactos más destacables de los procesos de evaluación y de acreditación sobre el cuerpo académico y sobre la institución universitaria. Se presenta también el resultado de un estudio cualitativo basado en entrevistas a docentes de la FRT-UTN, respecto a estos temas trascendentales

Nanostructure and crystallography of aberrant columnar vaterite in Corbicula fluminea (Mollusca)

Both the crystallographic and nanostructural organisation of aberrant columnar vaterite occurring in \ud C. fluminea were characterised in detail for the first time using electron microscopic and x-ray \ud powder diffraction techniques. At the millimetre scale, only a confinement of the otherwise \ud randomly oriented c-axis to the growth surface is observed. Domains of one hundred or more \ud individual vaterite columns with common c-axis orientation exist within this disordered material. \ud Each column behaves as a single crystal on the scale of EBSD measurements, but is internally \ud composed of smaller (0.3 – 1.3 μm in dimension) irregularly shaped and slightly misaligned \ud crystalline units. These are in turn partitioned by porous boundaries into rounded nanodomains, up \ud to 600 nm in size. The geometry of the nanodomains and their respective boundaries might suggest \ud formation by the accretion of vesicles. In addition to crystallographic textures, this observation \ud indicates formation under significant biological control with wider implications for possible causes \ud of the condition

The rise of (Chiral) 3D mechanical metamaterials

On the occasion of this special issue, we start by briefly outlining some of the history and future perspectives of the field of 3D metamaterials in general and 3D mechanical metamaterials in particular. Next, in the spirit of a specific example, we present our original numerical as well as experimental results on the phenomenon of acoustical activity, the mechanical counterpart of optical activity. We consider a three-dimensional chiral cubic mechanical metamaterial architecture that is different from the one that we have investigated in recent early experiments. We find even larger linear-polarization rotation angles per metamaterial crystal lattice constant than previously and a slower decrease of the effects towards the bulk lim

AFTER FURTHER REVIEW: AN UPDATE ON MODELING AND DESIGN STRATEGIES FOR AGRICULTURAL DOSE-RESPONSE EXPERIMENTS

Research investigating dose-response relationships is common in agricultural science. This paper is an expansion on previous work by Guo, et al. (2006) motivated by plant nutrition research in horticulture. Plant response to level of nutrient applied is typically sigmoidal, i.e. no response at very low levels, observable response at mid-levels, point-of-diminishing returns and plateau at high levels. Plant scientists need accurate estimates of these response relationships for many reasons, including determining the lower threshold below which plants show deficiency symptoms and the point of diminishing returns, above which excessive doses are economically and environmentally costly. Guo et al. presented models and designs that address these requirements and a simulation study to assess and compare the small-sample behavior of these models and designs. This paper expands on that simulation study. In addition, a simulation study based procedure for exploring designs for experimental scenarios fitting this description is presented. This simulation study approach utilizes simulation based fit statistics in conjunction with various lack-of-fit plots to produce a design robust to multiple candidate models

Hydrogen bonding and charge transport in a protic polymerized ionic liquid

Hydrogen bonding and charge transport in the protic polymerized ionic liquid poly[tris(2-(2-methoxyethoxy)ethyl)ammoniumacryloxypropyl sulfonate] (PAAPS) are studied by combining Fourier transform infrared (FTIR) and broadband dielectric spectroscopy (BDS) in a wide temperature range from 170 to 300 K. While the former enables to determine precisely the formation of hydrogen bonds and other moiety-specific quantized vibrational states, the latter allows for recording the complex conductivity in a spectral range from 10−2 to 10+9  Hz. A pronounced thermal hysteresis is observed for the H-bond network formation in distinct contrast to the reversibility of the effective conductivity measured by BDS. On the basis of this finding and the fact that the conductivity changes with temperature by orders of magnitude, whereas the integrated absorbance of the N–H stretching vibration (being proportional to the number density of protons in the hydrogen bond network) changes only by a factor of 4, it is concluded that charge transport takes place predominantly due to hopping conduction assisted by glassy dynamics (dynamic glass transition assisted hopping) and is not significantly affected by the establishment of H-bonds