Synthesis of planar inductors in low temperature co-fired ceramic technology

A simple bisection algorithm for the synthesis of planar inductors using a fast electromagnetic analysis algorithm is presented in this work. Both bisection and electromagnetic analysis algorithms are based on a set of heuristic and physical rules obtained from the study of the electromagnetic behavior of these planar devices. With this procedure, the benefits are two fold: (i) the number of iterations is kept moderately low in the synthesis loop, and (ii) the analysis at each iteration step is speed up without compromising accuracy. The algorithm is applied to the development of an inductor library for a low temperature co-fired ceramic process technology.     

Bitumen spreading on calcareous aggregates at high temperature

In hot asphalt applications, the adhesion between bitumen and mineral aggregate is usually described in terms of bitumen surface tension and contact angle of the bitumen over the aggregate. However, the quantification of the physico-chemical bond between bitumen and aggregate under realistic conditions is a nontrivial task. In this work, we designed a high-temperature goniometer to measure the contact angle of liquid bitumen on mineral aggregate substrates. The drop deposition was conducted once the thermal equilibrium between liquid bitumen and aggregate was attained. We monitored the spreading of sessile drops of viscous naphthenic bitumen and asphaltic bitumen on polished sheets of calcareous aggregates at high temperature (70–100 °C). A near complete wetting with very low contact angles (13– \(24^{\circ }\) ) was reproduced regardless of the bitumen origin and temperature. Furthermore, the coating degree of the naphthenic and asphaltic bitumens on the calcareous aggregates at high temperature was apparently similar. We found that the bitumen-aggregate adhesion is adequately described by dynamic spreading rather than by equilibrium wettability. Spreading kinetics was ruled by the particular properties of each bitumen such as viscosity and acid index. We found evidences of acid etching of the naphthenic bitumen on the calcareous aggregates during spreading at high temperature.     

Quality of Gamma- and X-Ray Inspections for Low Dimensional Parts

This paper studied and analysed the technique of X-ray inspection and the technique of inspection with \(^{60}\) Co (gamma-ray). The study analyzed eight standard samples certified by the American Welding Society with characteristic defectology weldment and thicknesses of 12 and 20 mm. The results obtained establish differences between each of the techniques used, identifying advantages and disadvantages of each. The experimental results are analyzed according to thickness, economy, portability, durability, safety and technical factors used in each radiographic technique, which show the benefits of using either technique.     

Unusual broadening of the NIR luminescence of Er-doped Nb2O5 nanocrystals embedded in silica host: Preparation and their structural and spectroscopic study for photonics applications

This paper reports on the preparation of novel sol-gel erbium-doped SiO₂-based nanocomposites embedded with Nb₂O₅ nanocrystals fabricated using a bottom-up method and describes their structural, morphological, and luminescence characterization. To prepare the glass ceramics, we synthesized xerogels containing Si/Nb molar ratios of 90:10 up to 50:50 at room temperature, followed by annealing at 900, 1000, or 1100 °C for 10 h. We identified crystallization accompanying host densification in all the nanocomposites with orthorhombic (T-phase) or monoclinic (M-phase) Nb₂O₅ nanocrystals dispersed in the amorphous SiO₂ phase, depending on the niobium content and annealing temperature. A high-intensity broadband emission in the near-infrared region assigned to the ⁴I_13/2 → ⁴I_15/2 transition of the Er³⁺ ions was registered for all the nanocomposites. The shape and the bandwidth changed with the Nb₂O₅ crystalline phase, with values achieving up to 81 nm. Er³⁺ ions were located mainly in Nb₂O₅-rich regions, and the complex structure of the different Nb₂O₅ polymorphs accounted for the broadening in the emission spectra. The materials containing the T-phase, displayed higher luminescence intensity, longer ⁴I_13/2 lifetime and broader bandwidth. In conclusion, these nanostructured materials are potential candidates for photonic applications like optical amplifiers and WDM devices operating in the S, C, and L telecommunication bands.     

Detection and Identification of Oestrogen‐Active Substances in Plastic Food Packaging Migrates

Migrates from plastic food packaging were tested for oestrogen activity by yeast oestrogen screen and subsequently analysed by gas chromatography—mass spectrometry and high‐performance liquid chromatography—mass spectrometry to identify oestrogen‐active chemicals. Plastic samples were migrated according to EC 10/2011 with worst case scenarios being used. Food simulants consisted of either 10–95% ethanol or ultrapure water. Migrates were concentrated afterwards by solid phase extraction. Food contact material tested included polyethylene terephthalate, polypropylene, polyethylene, polystyrene and composite films. Oestrogenic activity ranging from 0.7 to 59 ng/l 17ß‐estradiol equivalents was detected in seven out of 42 samples tested. The highest activity was found in a composite film sample. All 11 polyethylene terephthalate samples tested negative for oestrogen activity. A number of chemicals with known or supposed oestrogen activity were identified in migrates of oestrogen‐active samples. These include butylated hydroxytoluene, 1,3‐diphenylpropane, 1,2‐diphenylcyclobutane and dibutyl phthalate. Copyright © 2013 John Wiley & Sons, Ltd.     

PetFMM—A dynamically load‐balancing parallel fast multipole library

Fast algorithms for the computation of N‐body problems can be broadly classified into mesh‐based interpolation methods, and hierarchical or multiresolution methods. To this latter class belongs the well‐known fast multipole method (FMM ), which offers ??(N) complexity. The FMM is a complex algorithm, and the programming difficulty associated with it has arguably diminished its impact, being a barrier for adoption. This paper presents an extensible parallel library for N‐body interactions utilizing the FMM algorithm. A prominent feature of this library is that it is designed to be extensible, with a view to unifying efforts involving many algorithms based on the same principles as the FMM and enabling easy development of scientific application codes. The paper also details an exhaustive model for the computation of tree‐based N‐body algorithms in parallel, including both work estimates and communications estimates. With this model, we are able to implement a method to provide automatic, a priori load balancing of the parallel execution, achieving optimal distribution of the computational work among processors and minimal inter‐processor communications. Using a client application that performs the calculation of velocity induced by N vortex particles in two dimensions, ample verification and testing of the library was performed. Strong scaling results are presented with 10 million particles on up to 256 processors, including both speedup and parallel efficiency. The largest problem size that has been run with the P etFMM library at this point was 64 million particles in 64 processors. The library is currently able to achieve over 85% parallel efficiency for 64 processes. The performance study, computational model, and application demonstrations presented in this paper are limited to 2D. However, the software architecture was designed to make an extension of this work to 3D straightforward, as the framework is templated over the dimension. The software library is open source under the PETS c license, even less restrictive than the BSD license; this guarantees the maximum impact to the scientific community and encourages peer‐based collaboration for the extensions and applications. Copyright © 2010 John Wiley & Sons, Ltd.     

Reliability Assessment of Lifeline Systems with Radial Topology

Abstract: The increased susceptibility of lifeline systems to failure due to aging and external hazards requires efficient methods to quantify their reliability and related uncertainty. Monte Carlo simulation techniques for network‐level reliability and uncertainty assessment usually require large computational experiments. Also, available analytical approaches apply mainly to simple network topologies, and are limited to providing average values, low order moments, or confidence bounds of reliability metrics. This study introduces a closed form technique to obtain the entire probability distribution of a reliability metric of customer service availability (CSA) for generic radial lifeline systems. A special case of this general formulation reduces to a simple sum of products equation, for which a recursive algorithm that exploits its structure is presented. This special‐case algorithm computes the probability mass function (PMF) of CSA for systems with M elements in operations, relative to conventional operations, and opens the possibility of finding recursive algorithms for the general radial case. Parametric models that approximate the CSA metric are also explored and their errors quantified. The proposed radial topology reliability assessment tools and resulting probability distributions provide infrastructure owners with critical insights for informed operation and maintenance decision making under uncertainty.     

Fast Automated Determination of Total Tocopherol Content in Virgin Olive Oil Using a Single Multicommuted Luminescent Flow Method

Tocopherols are natural fluorophores of great importance for the characterization and authentication of virgin olive oil. Herein, a single automatic multicommuted flow method has been developed for the determination of total tocopherol content as well as the semi-quantitative estimation of α-tocopherol in extra virgin olive oil (EVOO) samples. Only appropriate dilution of samples with 2-propanol was necessary for their direct analysis by a multicommuted flow injection (MCFIA) manifold based on three solenoid valves with fluorescence detection. The peak height at λ _em = 330 nm (emission) with λ _exc at 296 nm was used as analytical signal. Linear response was observed within the range from 50 to 350 mg of tocopherols (expressed as α-tocopherol kg^?1 olive oil), suitable to cover the usual range for tocopherols in (extra) virgin olive oil ((E)VOO)). The results were consistent with those obtained by reversed-phase HPLC reference method, whereas the analysis time was significantly reduced. The sample frequency of the proposed automatic method was close to 40 samples h^?1, in contrast to typically 15–30 min required by HPLC. The method is fast, straightforward, cost-effective, and easy to implement in routine laboratories for screening purposes.     

An ultrastructural study of spermiogenesis in two species of Sitophilus (Coleoptera: Curculionidae).

The spermiogenesis of Sitophilus zeamais and Sitophilus oryzae, the maize and the rice weevil, respectively, was studied by light microscopy and scanning and transmission electron microscopy. Sitophilus spp. is the most widespread and destructive primary pest of stored cereals in the world. The spermiogenesis occurs within cysts. There are approximately 256 germ line cells per cyst. Inside each cysts, all the spermatids are in the same stage of maturation. The ultrastructure of the spermatozoa of S. zeamais and S. oryzae is similar to that described for other beetles. The head is formed by a three-layered acrosome with the perforatorium, the acrosomal vesicle, the extra-acrosomal layer and the nucleus. The flagellum has the typical axoneme formed by a 9+9+2 microtubules arrangement, two mitochondrial derivatives and two accessory bodies. The typical pattern for Curculionidae spermatozoa described here may provide useful information for future phylogenetic analysis of the superfamily Curculionoidea.     

Tetrachromacy, oil droplets and bird plumage colours

Survival rates in childhood cancer now approach approximately 65%, depending on the specific cancer. Success has been achieved through the use of increasingly aggressive treatments (chemotherapy, radiotherapy, bone-marrow transplantation). These are now recognised to be associated with a range of physical late effects, including problems associated with growth and endocrine function, sensory function, fertility, liver, cardiac, and kidney damage. Recognition of these physical late effects raises the issue of related problems in psychological, educational, and behavioural functioning. There is considerable evidence to suggest that children who are younger on diagnosis are more at risk in terms of cognitive and behavioural late effects compared with those who are diagnosed later. Cancer remains a rare disease in children and consequently only those professionals attached to centres specialising in the care of children with cancer are likely to receive a significant number of referrals. It is important to establish a psychological support service as an integral part of long-term care in order to (a) establish more accurately the incidence of social and psychological late effects and (b) offer advice to the individual about the possible long-term effects of cancer treatment on future health, social, and employment prospects.