Young's modulus of (Ti,Si)N films by surface acoustic waves and indentation techniques

Ti1yxSixNy films with Si contents up to 17.5 at.% and N contents close to 50 at.% were prepared by r.f. reactive magnetron sputtering. Film densities are within the range 3.4–5.1 gycm3.X-Ray diffraction patterns indicated the formation of two crystalline phases.In the case of low surface mobility, a metastable (Ti, Si)N phase was formed, where Si atoms occupied Ti positions. With increasing surface mobility, a crystalline TiN phase was observed.This behaviour may be explained by the occurrence of Si3N4 segregation, leading to the formation of a nanocomposite film of the type nc-TiNync-(Ti,Si)Nya-Si3N4, although the presence of Si3N4 phase is difficult to prove.In some of the films, a mixture of the (Ti,Si)N metastable phase with the TiN phase was observed, which indicates that the segregation of both TiN and Si3N4 phases is not complete.The Young’s modulus, Ef, of each coating was evaluated using both indentation tests and the surface acoustic waves (SAW) method.For most samples, the results obtained by these two methods are in good agreement.Some differences were observed in films prepared with a bias voltage of y50 V and Si contents higher than 5.9 at.%. For these samples, indentation values of approximately 10–20% higher than those obtained from SAW were found.This discrepancy is related to the nanostructure of these coatings, and it should be pointed out that the SAW results are strongly correlated with the density of the material.Fundação para a Ciência e Tecnologia (FCT)European Community Fund (FEDER)German/Portuguese DAAD/ICCTI Institution

Removal of Diclofenac by constructed wetlands planted with Phragmites australis and Typha spp.

In the modern society, an ever increasing number of pharmaceutical active compounds (PhACs) is used for the treatment and prevention of various diseases. Ingested drugs are only partially absorbed by the organisms and studies have shown that the excreted compounds are only partially removed in the sewage treatment plants (STPs) [1]. Diclofenac is a non-steroidal anti-inflammatory drug taken to reduce inflammation and as an analgesic reducing pain in certain conditions. In several studies, it was detected in surface water, thus indicating incomplete degradability of this substance in STPs. Despite the low concentrations detected (ng/L - μg/L), those studies have shown damaging effects of this and other pharmaceutical compounds on the aquatic ecosystems [2]. Subsurface flow constructed wetland systems (SSFs) are low cost wastewater treatment systems, usually used to provide a form of secondary or tertiary treatment for wastewaters. Depuration in SSFs is achieved by the concerted action between plant rhizomes, microorganisms and the support matrix components. SSFs’ efficiency can be significantly improved by optimization of the operation conditions which is achieved by careful selection of the support matrices, plants and microorganisms used. The aim of the present work was to evaluate the efficiency of SSF microcosms planted with Phragmites australis and Typha spp plants, to remove diclofenac from contaminated water. The wastewater samples were collected from a STP located in Évora-Portugal. In order to optimize the role played by the support matrix, light expanded aggregates (LECA) and cork, a very common material in Alentejo, were tested. Two different assays were performed, in winter and summer time, using doped wastewater, to evaluate the removal rates of diclofenac by the SSF systems. The quantification of diclofenac was achieved using HPLC-UV with a reversed phase column. [3]. The study results show that constructed wetlands can be an alternative system for removing diclofenac from contaminated water. REFERENCES [1] Fent, K., Weston, A. N., and Caminada, D., Aquatic Toxic. 76 (2006) 122. [2] Maurer, M., Escher, B.I., Richle, P., Schaffner, C., and Alder, A.C., Water Research 41 (2007) 1614. [3] Dordio A., Pinto J., Dias C., Pinto A.P., Carvalho A., Teixeira D.M., International Journal of Environmental Analytical Chemistry, 89 (2009) 835

Distributed/virtual manufacturing system cell: an experimental installation

The main objectives of the “Distributed/Virtual Manufacturing System (D/V MS) Cell” project are: (1) The development of Tele-services technologies and organisation for the production planning and control functions; (2) The development of permanent high performance laboratory facilities that enable development and demonstration of D/V MS design and control, i.e., global distribution of production planning and control functions; (3) The development of an abstract environment, i.e., a virtual environment for design and real time control of manufacturing systems, or one of its elements, independent of the physical implementations. The D/V MS Cell satisfies the defined hierarchical distributed control model The Hardware System of the D/V MS Cell is composed by: (1) Machine tool cell: CNC milling machine, external sensors and actuators, interface computer with communications links, (2) Machine cell: Two machine simulators, PLC, sensors and actuators, computer based local controller, (3) Robot cell: Robot SCORBOT ER-VII, artificial vision system, conveyor system, computer based local controller, (4) Control centre: Video projector, computer based remote controller, computer based real time video and audio system. The Software System of the D/V MS Cell is composed by: (1) Applications for Human-Computer Interface (HMI): Interfaces for machine tool and robot programming and control, interface for production planning and control, (2) Computer-Machine Interface, via RS-232C, (3) Computer-Computer Interface, for communications via Internet. The hardware structure of the (D/V MS) Cell is already implemented and interfaces for machine tool programming and control are developed (software system). The operation of the complete system is planned for the year 1999

SU(3) Mixing for Excited Mesons

The SU(3)-flavor symmetry breaking and the quark-antiquark annihilation mechanism are taken into account for describing the singlet-octet mixing for several nonets assigned by Particle Data Group(PDG). This task is approached with the mass matrix formalism

Characterization of cookies formulated with rice and black bean extruded flours.

The aim of this work was to formulate cookies using extruded flour from by-products of rice and common beans industries, such as broken rice and split old bean grains, in order to make available foods with added nutritional value as other options to consumers. The market of ready to eat and high quality products is increasing in the world considering the new habits and life style of modern consumers. Different proportions of rice and black bean (whole ? WBF or peeled grain - PBF) pre-gelatinized flours were used to prepare the cookies by partially replacing the corn starch in the original recipe. The samples were characterized for physicochemical and sensory parameters. The final products showed an interesting nutritional composition. The increase of mixed flour on cookies formulation contributed to an increase of vitamin B content. There was no tannin content detected in the final products and the level of phytate was very low with no significant difference among samples. A significant difference between products was observed for some colour parameters. The sensory analyses showed that consumers ?liked lightly? the cookies with 15% and 30% PBF and 15% WBF. Cookies formulated with WBF had lower acceptance by consumers in terms of appearance and only those with 30% WBF had an intermediate score (?neither like, neither dislike?) for global acceptability. Regarding texture, when a higher amount of both flour (PBF and WBF) was applied it was observed an increase of cookie hardness and fracturability values. In conclusion it is viable to produce acceptable cookies using a rice and black bean extruded flour and then diversify the application of these by-products generated by their processing industries.Publicado também como artigo em periódico indexado em: Procedia Food Science, v. 1, p. 1645-1652, 2011

Self-managing postoperative pain with the use of a novel, interactive device: a proof of concept study

Background: Pain is commonly experienced following surgical procedures. Suboptimal management is multifactorial. Objectives. The primary objective was to assess whether patients used a device (Navimed) to self-report pain over and above a normal baseline of observations. Secondary outcome measures included comparison of pain scores and patient use of and feedback on the device. Methods: In a prospective randomized controlled trial, elective gynaecological surgery patients received standard postoperative pain care or standard care plus the Navimed, which allowed them to self-report pain and offered interactive self-help options. Results: 52 female patients, 26 in each of device and standard groups, did not differ in the frequency of nurse-documented pain scores or mean pain scores provided to nurses. The device group additionally reported pain on the device (means 18.50 versus 11.90 pain ratings per day, t(32) = 2.75, p < 0.001) that was significantly worse than reported to nurses but retrospectively rated significantly less anxiety. 80% of patients found the device useful. Discussion and Conclusion: This study demonstrates that patients used the Navimed to report pain and to help manage it. Further work is required to investigate the difference in pain scores reported and to develop more sophisticated software

Knotting probabilities after a local strand passage in unknotted self-avoiding polygons

We investigate the knotting probability after a local strand passage is performed in an unknotted self-avoiding polygon on the simple cubic lattice. We assume that two polygon segments have already been brought close together for the purpose of performing a strand passage, and model this using Theta-SAPs, polygons that contain the pattern Theta at a fixed location. It is proved that the number of n-edge Theta-SAPs grows exponentially (with n) at the same rate as the total number of n-edge unknotted self-avoiding polygons, and that the same holds for subsets of n-edge Theta-SAPs that yield a specific after-strand-passage knot-type. Thus the probability of a given after-strand-passage knot-type does not grow (or decay) exponentially with n, and we conjecture that instead it approaches a knot-type dependent amplitude ratio lying strictly between 0 and 1. This is supported by critical exponent estimates obtained from a new maximum likelihood method for Theta-SAPs that are generated by a composite (aka multiple) Markov Chain Monte Carlo BFACF algorithm. We also give strong numerical evidence that the after-strand-passage knotting probability depends on the local structure around the strand passage site. Considering both the local structure and the crossing-sign at the strand passage site, we observe that the more "compact" the local structure, the less likely the after-strand-passage polygon is to be knotted. This trend is consistent with results from other strand-passage models, however, we are the first to note the influence of the crossing-sign information. Two measures of "compactness" are used: the size of a smallest polygon that contains the structure and the structure's "opening" angle. The opening angle definition is consistent with one that is measurable from single molecule DNA experiments.Comment: 31 pages, 12 figures, submitted to Journal of Physics

Phenomenological model for the remanent magnetization of dilute quasi-one-dimensional antiferromagnets

We present a phenomenological model for the remanent magnetization at low temperatures in the quasi-one-dimensional dilute antiferromagnets CH_{3}NH_{3}Mn_{1-x}Cd_{x} Cl_{3}\cdot 2H_{2}O and (CH_{3})_{2}NH_{2}Mn_{1-x}Cd_{x}Cl_{3}\cdot 2H_{2}O. The model assumes the existence of uncompensated magnetic moments induced in the odd-sized segments generated along the Mn(^{2+}) chains upon dilution. These moments are further assumed to correlate ferromagnetically after removal of a cooling field. Using a (mean-field) linear-chain approximation and reasonable set of model parameters, we are able to reproduce the approximate linear temperature dependence observed for the remanent magnetization in the real compounds.Comment: 5 pages, 2 figures; final version to appear in Physical Review

A Transfer Matrix Method for Resonances in Randall-Sundrum Models

In this paper we discuss in detail a numerical method to study resonances in membranes generated by domain walls in Randall-Sundrum-like scenarios. It is based on similar works to understand the quantum mechanics of electrons subject to the potential barriers that exist in heterostructures in semiconductors. This method was used recently to study resonances of a three form field and lately generalized to arbitrary forms. We apply it to a lot of important models, namely those that contain the Gauge, Gravity and Spinor fields. In many cases we find a rich structure of resonances which depends on the parameters involved.Comment: 25 pages, 17 figure