908 resultados para Perfect antireflection coatings
Resumo:
The Danish Minister of Social Affairs is a very eager protagonist of quality in treatment, almost searching for the “perfect“ treatment for children, youngsters, disabled, etc. Many expensive research projects dealing with quality management as well as developmental projects have been launched during the latest years in order to improve professional practice. Within that context this article will deal with the relations between paternalism and ignorance and between pro-social behaviour and anti-social treatment in order to grasp “why professions are doing vicious things“. The main focus is concerned with the knowledge field of social pedagogy.
Resumo:
In West African languages that have the relative TAM marking, i.e., a system of syntactically conditioned alternating TAM paradigms, it is generally considered that the paradigms in each alternating pair have necessarily the same meaning. This paper shows that in Hausa, the Completive, which appears in pragmatically neutral clauses, and the Relative Perfective, which appears in pragmatically marked clauses (such as relative clauses), have, respectively, a basic perfect and perfective semantics, and that in some marked cases the alternation is not possible. The paper also shows that the two paradigms have acquired derived uses in a way consistent with the results of typological studies in the domain of tense/aspect.
Resumo:
In this note, we show that an extension of a test for perfect ranking in a balanced ranked set sample given by Li and Balakrishnan (2008) to the multi-cycle case turns out to be equivalent to the test statistic proposed by Frey et al. (2007). This provides an alternative interpretation and motivation for their test statistic.
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A wirelessly controlled magnetic microrobot has been proposed to diagnose and treat pathologies in the posterior segment of the human eye. The robot consists of a magnetic CoNi platform with a conformal coating of functional polymers. Electrodeposition has been the preferred method to fabricate and to functionalize the microrobot. Poly(pyrrole), a widely studied intrinsically conductive polymer has been investigated as a biocompatible coating to reduce biofouling, and as a coating that can release incorporated drugs on demand. The mechanism of redox cycling has been investigated to reduce the stiction of NIH 3T3 fibroblasts onto poly(pyrrole) surfaces. To demonstrate triggered drug release, Rhodamine B has been incorporated into the Ppy matrix as a model drug. Rapid Rhodamine B release is obtained when eddy current losses are induced by alternating magnetic fields on the CoNi substrates underneath these films.
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Many techniques based on data which are drawn by Ranked Set Sampling (RSS) scheme assume that the ranking of observations is perfect. Therefore it is essential to develop some methods for testing this assumption. In this article, we propose a parametric location-scale free test for assessing the assumption of perfect ranking. The results of a simulation study in two special cases of normal and exponential distributions indicate that the proposed test performs well in comparison with its leading competitors.
Resumo:
Initialising the ocean internal variability for decadal predictability studies is a new area of research and a variety of ad hoc methods are currently proposed. In this study, we explore how nudging with sea surface temperature (SST) and salinity (SSS) can reconstruct the threedimensional variability of the ocean in a perfect model framework. This approach builds on the hypothesis that oceanic processes themselves will transport the surface information into the ocean interior as seen in ocean-only simulations. Five nudged simulations are designed to reconstruct a 150 years ‘‘target’’ simulation, defined as a portion of a long control simulation. The nudged simulations differ by the variables restored to, SST or SST + SSS, and by the area where the nudging is applied. The strength of the heat flux feedback is diagnosed from observations and the restoring coefficients for SSS use the same time-scale. We observed that this choice prevents spurious convection at high latitudes and near sea-ice border when nudging both SST and SSS. In the tropics, nudging the SST is enough to reconstruct the tropical atmosphere circulation and the associated dynamical and thermodynamical impacts on the underlying ocean. In the tropical Pacific Ocean, the profiles for temperature show a significant correlation from the surface down to 2,000 m, due to dynamical adjustment of the isopycnals. At mid-tohigh latitudes, SSS nudging is required to reconstruct both the temperature and the salinity below the seasonal thermocline. This is particularly true in the North Atlantic where adding SSS nudging enables to reconstruct the deep convection regions of the target. By initiating a previously documented 20-year cycle of the model, the SST + SSS nudging is also able to reproduce most of the AMOC variations, a key source of decadal predictability. Reconstruction at depth does not significantly improve with amount of time spent nudging and the efficiency of the surface nudging rather depends on the period/events considered. The joint SST + SSS nudging applied verywhere is the most efficient approach. It ensures that the right water masses are formed at the right surface density, the subsequent circulation, subduction and deep convection further transporting them at depth. The results of this study underline the potential key role of SSS for decadal predictability and further make the case for sustained largescale observations of this field.
Resumo:
For preventing erosive wear in dentine, coating with adhesives has been suggested as an alternative to fluoridation. However, clinical studies have revealed limited efficacy. As there is first evidence that Sn(2+) increases bond strength of the adhesive Clearfil SE (Kuraray), the aim of the present study was to investigate whether pre-treatment with different Sn(2+)/F(-) solutions improves the durability of Clearfil SE coatings. Dentine samples (eight groups, n=16/group) were freed of smear layer (0.5% citric acid, 10 s), treated (15 s) either with no solution (control), aminefluoride (AmF, 500 ppm F(-), pH 4.5), SnCl2 (800/1600 ppm Sn(2+); pH 1.5), SnCl2/AmF (500 ppm F(-), 800 ppm Sn(2+), pH 1.5/3.0/4.5), or Elmex Erosion Protection Rinse (EP, 500 ppm F-, 800 ppm Sn(2+), pH 4.5; GABA International), then rinsed with water (15 s) and individually covered with Clearfil SE. Subsequently the specimens were subjected to an erosion/abrasion protocol consisting of 1320 cycles of immersion in 0.5% citric acid (5 °C/55 °C; 2 min) and automated brushing (15 s, 200 g, NaF-toothpaste, RDA 80). As the coatings proved stable up to 1320 cycles, 60 modified cycles (brushing time 30 min/cycle) were added. Wear was measured profilometrically. After SnCl2/AmF, pH 4.5 or EP pre-treatment all except one coating survived. In the other groups, almost all coatings were lost and there was no significant difference to the control group. Pre-treatment with a Sn(2+)/F(-) solution at pH 4.5 seems able to improve the durability of adhesive coatings, rendering these an attractive option in preventing erosive wear in dentine.
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Cadmium has been widely used as a coating to provide protection against galvanic corrosion for steels and for its natural lubricity on threaded applications. However, it is a toxic metal and a known carcinogenic agent, which is plated from an aqueous bath containing cyanide salts. For these reasons, the use of cadmium has been banned in Europe for most industrial applications. However, the aerospace industry is still exempt due to the stringent technical and safety requirements associated with aeronautical applications, as an acceptable replacement is yet to be found. Al slurry coatings have been developed as an alternative to replace cadmium coatings. The coatings were deposited on AISI 4340 steel and have been characterized by optical and electron microscopy. Testing included salt fog corrosion exposure, fluid corrosion exposure (immersion), humidity resistance, coating-substrate and paint-coating adhesion, electric conductivity, galvanic corrosion, embrittlement and fatigue. The results indicated that Al slurry coatings are an excellent alternative for Cd replacement.
Resumo:
The perfect drain for the Maxwell fish eye (MFE) is a non-magnetic dissipative region placed in the focal point to absorb all the incident radiation without reflection or scattering.