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Carbon fibre reinforced polymer/titanium stacks (CFRP/Ti6Al4V) are employed in aeronautics due to their excellent weight-to-strength ratio and corrosion properties. However, these same material properties present challenges for hole making which cannot be solved using conventional water-based metalworking fluids (MWFs), as they cause degradation of the composite. Moreover, environmental and health concerns require exploration of alternative cooling/lubrication solutions. In this study, a controlled mixture of liquid carbon dioxide (LCO 2) and minimum quantity lubrication (MQL) was supplied through the drilling tool. The effect of varying LCO 2 and MQL flow rates was evaluated on cutting forces, temperatures, and several hole quality outputs. The optimal flow rates were then determined through multi-objective optimisation. The results show that the cooling/lubrication flow rate greatly affects the measured outputs, and that supplying LCO 2 + MQL with optimised flow rates helps achieve superior quality holes in CFRP, Ti6Al4V and CFRP/Ti6Al4V stacks. [ABSTRACT FROM AUTHOR]

• DNS and LES of the flow and heat transfer past a sphere are performed. • Local and average Nusselt number are determined. • Viscous and thermal boundary layer are analysed. • Wake behaviour and its characteristics are studied for moderate Reynolds numbers. Direct numerical simulation and large-eddy simulation have been performed for a heated sphere at Reynolds numbers of R e = 1000 and R e = 10 4 , respectively. The Prandtl number for both simulations has been P r = 0.7. Measurements of the local and average Nusselt number are performed and compared with literature available experimental results. Average and front stagnation point Nusselt numbers increase with the Reynolds number, while the minimum value moves towards the sphere apex as the flow enters the sub-critical regime. Differences in both viscous and thermal boundary layers are observed, while the shape factor at Reynolds number R e = 10 4 behaves similarly to that observed in circular cylinders at comparable Reynolds numbers. It is shown that as the Reynolds number increases, the increase in turbulent kinetic energy promotes the entrainment of irrotational flow thus enhancing the temperature mixing in the zone. The near wake, between 5 ≤ x / D ≤ 15, spreads at a faster rate at R e = 1000 with a slope close to x / D 1/2, while at R e = 10 4 it follows a trend close to x / D 1/3. [ABSTRACT FROM AUTHOR]

Abstract Radiotherapy of cancer has been traditionally considered as a local therapy without noticeable effects outside the irradiated fields. However, ionizing radiation exerts multiple biological effects on both malignant and stromal cells that account for a complex spectrum of mechanisms beyond simple termination of cancer cells. In the era of immunotherapy, interest in radiation-induced inflammation and cell death has considerably risen, since these mechanisms lead to profound changes in the systemic immune response against cancer antigens. Immunotherapies such as immunomodulatory monoclonal antibodies (anti-PD-1, anti-CTLA-4, anti-CD137, anti-OX40, anti-CD40, anti-TGFβ), TLR-agonists, and adoptive T-cell therapy have been synergistically combined with radiotherapy in mouse models. Importantly, radiation and immunotherapy combinations do not only act against the irradiated tumor but also against distant non-irradiated metastases (abscopal effects). A series of clinical trials are exploring the beneficial effects of radioimmunotherapy combinations. The concepts of crosspriming of tumor neoantigens and immunogenic cell death are key elements underlying this combination efficacy. Proinflamatory changes in the vasculature of the irradiated lesions and in the cellular composition of the leukocyte infiltrates in the tumor microenvironment contribute to raise or dampen cancer immunogenicity. It should be stressed that not all effects of radiotherapy favor antitumor immunity as there are counterbalancing mechanisms such as TGFβ, and VEGFs that inhibit the efficacy of the antitumor immune response, hence offering additional therapeutic targets to suppress. All in all, radiotherapy and immunotherapy are compatible and often synergistic approaches against cancer that jointly target irradiated and non-irradiated malignant lesions in the same patient. [ABSTRACT FROM AUTHOR]

The analysis has shown that the location of Ag-acceptor levels in ZnO is still unclear. To identify Ag related defects the emission, structure and aging process have been studied in the silver doped ZnO nanocrystalline films obtained by the ultrasonic spray pyrolysis with different Ag concentrations within of 1–4 at%. It is revealed that at low Ag doping (1–2 at%) the ZnO crystal structure improves, but the higher (3–4 at%) Ag content leads to crystal lattice disordering. The bright emission related to Ag doping with PL peaks at 2.68 and 2.97 eV at 10 K have been detected in PL spectra of ZnO:Ag films at 2–3 at% Ag. At higher Ag content (≥ 3 at%) the PL intensity of majority PL bands falls down together with the formation of metallic Ag inclusions in ZnO:Ag films. At aging ZnO:Ag films the intensities of PL bands (2.68 and 2.97 eV) fall down, but the intensity of orange PL band increases. The study of PL temperature dependences permits to analyze the nature of emitting defects responsible for the blue (2.68 and 2.97 eV), green and orange PL bands. The transformation of emitting defects at aging has been discussed. [ABSTRACT FROM AUTHOR]

As a continuation of our previous study, in this work, we investigated the effects of propanol and butanol treatments and subsequent irradiation with microwave on commercial vermiculites. No expansibility was observed after propanol or butanol treatments (k = 1.0). Samples treated with propanol or butanol and subsequently irradiated with microwaves expanded in a similar manner as they did with methanol and ethanol. The results of X-ray diffraction (XRD), thermogravimetric analysis (TG and DTA), scanning electron microscopy (SEM) and infrared spectroscopy indicated structural changes as: 1) The appearance of extra interstratified phases during the transformation from 2- to 1-WLHS (Water Layer Hydration States). 2) The improvement of the crystallinity and order of the most phases, which are the same phases of the untreated vermiculites or even some more, due to migration of potassium. [ABSTRACT FROM AUTHOR]

Direct numerical simulations of the flow and forced convective heat transfer around a sphere at Reynolds numbers between R e = 500 and R e = 1000 are performed. We investigate the effects of the Prandtl number (P r) on the forced convective heat transfer from a sphere for various fluids having P r = 0. 01 , 0. 1 , 0. 7. At the larger Prandtl number, the convective transport due to the vortex shedding process dominates over the diffusive transport. As the Prandtl number decreases, diffusive effects become important. Moreover, the thermal boundary layer increases with decrements of the Prandtl number, which results in a reduction in the local and mean non-dimensional heat transfer coefficient. It is seen that at R e = 500 and R e = 750 , the vortex shedding process is asymmetric, which results not only in a non-zero lift coefficient, but in an asymmetric temperature field in the wake of the sphere at P r ≥ 0. 1. The dual asymmetry in the flow and the convective heat transfer is smooth out when the Prandtl number reaches P r = 0. 01 as the heat diffusion dominates and asymmetries in the vortex formation zone are no longer relevant in the heat transport. The descend in Prandtl number also produces an attenuation of the temperature fluctuations and thereby, in the turbulent heat transfer. As a direct consequence, two factors emerge at P r = 0. 01 : (1) a lower decay ratio of the temperature in the wake centreline, and (2) a larger wake spread compared to higher Prandtl numbers. [ABSTRACT FROM AUTHOR]

Significant research efforts are being devoted to the development of distributed electricity networks that aim to facilitate the gradual integration of manageable loads and distributed energy resources. These environments are conceived as self-managed, enclosed areas of the distribution network that integrates many of the technologies and information systems that will be part of the future Smart Grid. Both the new scheme and devices are expected to offer users presence in the grid operation so that their preferences and interests are relevant. To this end, the management system has been frequently proposed in form of an electronic market in which producers and consumers exchange energy blocks so that the consumption and production are continuously balanced. As the state of the art reflects, intelligent agents are an suitable technology for building energy management systems in which users participate actively in an intelligent and autonomous manner. This document presents a review of the most relevant works that tackle the safe and effective management of distributed electricity networks through autonomous software agents that negotiate on behalf of customers. This document presents a discussion of the suitability of the most relevant works, highlighting those that are most promising, and identifying the issues that are still necessary to reinforce in future research. [ABSTRACT FROM AUTHOR]

Present work reports the alcohol treatment and subsequent irradiation with microwave of commercial vermiculites. Alcohol treatment resulted in slight delamination of the layers and the color of the samples changed into brilliant golden and no expansibility was observed (k ≤ 1.3). Samples treated with alcohol and subsequently irradiated with microwaves expanded; the greater expansibility (k = 8 for 1 h) was provided by the most complex sample and treated with methanol. The structural changes were studied by using X-ray diffraction (XRD), thermogravimetric analysis (TG and DTA), infrared spectroscopy and carbon analysis. The results of these analysis indicated dehydration-hydration and order–disorder which would be related to the entry of alcohol into the vermiculites and the loss of water content. The changes occurred in a similar way to the temperature and vacuum, and were less pronounced for the purest vermiculite. The crystallite size and lattice strain values which reflect changes in crystallinity and structural order varied slightly regardless of treatment and time. Alcohol treatment and subsequent microwave irradiation may be the procedure for obtaining purest vermiculite from less pure sample. [ABSTRACT FROM AUTHOR]

In solutions based on simultaneous auctions, participants are enabled to conduct and clear their own auctions, so that many auctions can be running at the same time. This configuration is increasingly being proposed for the installation of distributed management systems based on economic criteria in contexts such as the Smart Grid, computational grids and the cloud. In particular, these solutions are commonly complemented by the presence of software agents which automate the users’ participation in an intelligent manner. This work focuses on the effect that the distribution of the bidders’ participation actually has on the effectiveness of parallel auctions as management system. Firstly, the problem is introduced, showing that, in practice, bidders have incentives to prefer some auctions over others, thus tending to concentrate their participation in a limited subset of auctions. Also, as part of the theoretical formulation, with the aim of preserving the essence of markets and keeping competition active, it establishes a set of players’ essential rights that any solution to the problem should preserve. The text then continues with the design and implementation of a regulatory mechanism that uniformly distributes buyers’ participation among the available auctions. Realistic experiments are provided in order to demonstrate both the negative effects that buyers’ concentration actually causes, and the effectiveness of the new regulatory mechanism, which manages to strengthen parallel auctions as a distributed management system. Likewise, it is proven that the solution is scalable, reactive and suitable for large distributed environments. [ABSTRACT FROM AUTHOR]

The most successful peer-to-peer networks are based on the concept of supernode, which is an operating point of the network that provides services and advanced functionalities to other nodes. Inspired by this idea, this paper proposes to integrate nodes that provide intelligent advanced services in the future architecture of the electrical grid. Besides facilitating the access to data services such as demand estimations and weather forecasts, these nodes are especially meant to hold virtual environments in which software agents, after being contracted, negotiate on behalf of users in energy markets. This architecture is designed to be compatible with the Energy Interoperation OASIS standard. The capabilities and feasibility of the proposal is demonstrated through realistic experiments based on OpenADR programs, in which users exchange energy by using parallel auction markets. In addition, in order to have the roles of buyer and seller in demand-response programs, thus allowing the creation of markets, a conceptual model based on negative loads and critical loads is provided. The experiments have proven that the proposed architecture facilitates the implementation of advanced distributed management systems in order that smart metering infrastructures, in contrast with traditional agent-based solutions, are released to perform negotiation tasks and access data services, while users gain both autonomy and decision-making capacity. [ABSTRACT FROM AUTHOR]

Abstract: This research presents a structural and photocarrier radiometric (PCR) characterization of Cu x (CdTe) y O z thin films grown using reactive radiofrequency co-sputtering. Electronic distribution induced by variations in dopant concentration as a function of the position was studied using photocarrier radiometric images. Optical and structural characterization of these thin films was carried out by using micro Raman spectroscopy and X-ray diffraction. Due to its nondestructive and noncontact characteristics, the PCR is an excellent technique that permits one to obtain details of lateral electronic distribution across the sample. It was found that Cu target power influences the electronic distribution and produces different phases such as Cu2Te and CdO. [ABSTRACT FROM AUTHOR]

Abstract: The ion Er3+ was introduced into a new kind of glassy matrices prepared from a mixture of CdO–ZnO–V2O5 and Er(NO3)3·5H2O as source of Er3+ ions. The obtained glasses were characterized by infrared spectroscopy and micro photoluminescence and micro Raman spectroscopies. The glass formation process produced Al diffusion from the crucible to the oxides mixture yielding crystalline micro aggregates. The room temperature photoluminescence spectra showed transitions from different Er3+ levels in the 450–900nm range. In particular, the 4F9/2 → 4I15/2 transitions were strongly affected by local electric fields since these transitions presented Stark effect splittings whose intensity was dependent on the atomic order surrounding the Er3+ ions. It was found that a highly reproducible multiplet emission was particularly strong in crystalline micro-regions of Zn x Al2− x O3 immersed in the vitreous matrix. [Copyright &y& Elsevier]

Abstract: The cooling process by natural convection in cylindrical cavities is a phenomenon which takes place in several applications such as solar energy systems. In the present work a storage tank with an internal gas flue is studied experimentally and numerically during its long-term cooling process. The computational domain includes two fluids, i.e. water in the store and air in the chimney, and two external and internal layers of steel separated by polyurethane insulation material. In this paper, the numerical and the experimental analysis of the temperature field inside the tank submitted to an external convection cooling process with a constant convection heat transfer coefficient is presented. The air and the water temperature profiles along the vertical lines are obtained experimentally and numerically, for a cooling period of 90h. The numerical analysis is carried out using a specific CFD code developed for the present work; an axisymmetric domain has been considered. Finally, a detailed description of the phenomena that occur inside the water part of the domain during the cooling process is also provided. [Copyright &y& Elsevier]

Abstract: In the computerized generation of human poses, it is important to take into account not only the active component of the torque, but also the ligaments and connective tissues which produce a passive torque at the limits of the joint range of motion. We present a fatigue model in which both active and passive torque components are essential parameters integrated in an inverse kinematics animation framework. We then use fatigue evolution to optimize the generated posture. We introduce an hysteresis activation pattern for each joint in order to set, whenever necessary, a fatigue reduction scheme through an active torque reduction constraint. The fatigue reduction scheme analyzes the fatigue level of each individual muscular group; when it is above a given threshold, a statically optimal joint variation is enforced to locally reduce the active torque while still achieving a desired task (e.g. reaching a point in 3D space). For that purpose we integrate the influence of passive/resistive torque in an active torque reduction scheme, allowing either the generation of reactive poses (i.e. an active strategy) or, on the contrary, the adoption of more relaxed ones (i.e. a passive strategy). [Copyright &y& Elsevier]

Abstract: The efficiencies of two methods of functionalizing single wall carbon nanotubes (SWCNTs) are compared, either through a radical addition of 4-methoxyphenylhydrazine hydrochloride by a classical thermally activated procedure, or via a microwave-assisted method. X-ray photoelectron spectroscopy and thermal gravimetric analysis clearly indicate the efficiency of both methods. Raman and absorption spectroscopy further confirm the functionalization and reveal the covalent nature of the bonds created at the carbon nanotube surface. For the microwave-assisted reaction, 5–15min is enough to functionalize the SWCNTs. Longer microwave exposure times reduce the functionalization yield and lead to a removal of groups which were bonded in a previous stage. An optimal choice of microwave irradiation time allows reducing the reaction time from days to minutes. [Copyright &y& Elsevier]

Abstract: We report a new SWNT functionalization method through 4-methoxyphenyl free radical addition. The 4-methoxyphenyl radicals are generated by air oxidation of 4-methoxyphenylhydrazine hydrochloride. Absorption and Raman spectroscopy show the covalent nature of the bond between the nanotubes and the functional groups. The XPS and TGA data furnish quantitative information on the degree of functionalization. [Copyright &y& Elsevier]

Abstract: A solid-phase microextraction (SPME) method for the determination of triclosan, methyl triclosan, 2,4-dichlorophenol and 2,3,4-trichlorophenol (considered as possible triclosan metabolites) in water samples was optimised. Analytes were first concentrated on a SPME fibre, directly exposed to the sample, and then triclosan and the two chlorinated phenols on-fibre silylated using N-methyl-N-(tert.-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA). Methyl triclosan remained unaffected during the derivatization step. Compounds were determined using gas chromatography in combination with mass spectrometry (GC–MS). Influence of different factors on the efficiency of extraction and derivatization steps was systematically investigated. Using a polyacrylate (PA) fibre quantification limits below 10ng/l, and acceptable relative standard deviations, were obtained for all compounds after an extraction time of 30min. On-fibre silylation was carried out in only 10min. Moreover, the efficiency of the procedure was scarcely affected by the type of water sample. The method was applied to several samples of treated and raw wastewater, triclosan was found in all samples, at concentrations from 120 to 14,000ng/l, and 2,4-dichlorophenol in most of them, at levels up to 2222ng/l. [Copyright &y& Elsevier]

New phosphines containing the homopiperazine backbone have been prepared. The X-ray structure of the P(III) phosphine and its P(V) sulphide are compared. The P–N bond length is shortened on oxidation from P(III) to P(V). [Copyright &y& Elsevier]

Reaction of isophthaloyl dichloride with two equivalents of benzylamine in the presence of Et3N gives N,N′-dibenzyl-1,3-isophthaldiamide which reacts with two equivalents of Ph2PCl, in the presence of n-BuLi at −78 °C to give 1,3-C6H4-{C(O)N(PPh2)CH2Ph}2 (1). Reaction of 1 with [PtCl2(cod)] in dichloromethane gives the P,P′,C tridentate bis-chelate [Pt(Cl){1,3-C6H4-{C(O)N(PPh2)CH2Ph}2}] (2), whilst reaction of 1 with two equivalents of [(C3H5)PdCl]2 in thf results in [{PdCl(C3H5)}2 {1,3-C6H4-{C(O)N(PPh2)CH2Ph}2}] (3) in which the ligand bridges two palladium centres. The X-ray structures of 2 and 3 are reported. [Copyright &y& Elsevier]

Ancient silver Mexican coins made during the years 1730–1734, were analyzed non-destructively by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and by optical microscopy. Nine coins of denomination eight Reales were studied. These coins belong to the numismatic private collection in Mexico. Six elements (copper, aluminum, magnesium, silicon, chromium and silver) were determined quantitatively. The coins reveal a uniform Ag concentration. Some of the items are covered with patina. A strong positive correlation between Al and Cu content and also a strong negative correlation between S and Ag were determined. The weight of the coins varied between 26.1344 and 26.9913 g, which is a good indicator of the authenticity of the items. The purpose of this work is to investigate by precise means if some of the coins were falsified or if really all of them are authentic. [Copyright &y& Elsevier]

The synthesis, oxidation and coordination chemistry of new bis(aminophosphines) based on diamines is demonstrated. Ph2PN(CH2Ph)CH2CH2(CH2Ph)NPPh2, iPr2PN(CH2Ph)CH2CH2(CH2Ph)NPiPr2, Ph2PNH(C10H6)2NHPPh2, Ph2PNH(C10H6)(C6H4)NHPPh2 were prepared and tested in the hydroformylation of hex-1-to give aldehydes with poor selectivity (up to l:b=2.5:1) to the desired linear products. Modelling calculations were performed for all ligands. R2 groups enlarge the natural bite angle when going from R2=Ph2 to R2=iPr2 which are more bulky. Most of the ligands seem to be rigid (with flexibility ranges of 25°–46°). Four demonstrative X-ray structures are reported. [Copyright &y& Elsevier]

Reaction of piperazine or homopiperazine with R2PCl [R2=Ph2, OC2H4O, OC6H4O] gives six new bidentate phosphines. Simple bis-chelate and bridging complexes with demonstrative Mo(0), Pd(II), Pt(II) and Ru(II) centres are reported. The crystal structures of Ph2P(O)N(C2H4)2P(O)Ph2, cis-[PdCl2{Ph2PN(C2H4)2NPPh2}] (7) and cis-[PtCl2{Ph2PN(C5H10)NPPh2}][PtcodCl2]2 (15) are reported. In Ph2P(O)N(C2H4)2P(O)Ph2 the central N2C4 ring has a chair conformation and the P&z.dbnd6;O groups are trans. In 7 the piperazine backbone results in P&z.sbnd;Pd&z.sbnd;P bite angle of approximately 95° whilst in 15 the homopiperazine backbone enlarges the bite angle to 97°. [Copyright &y& Elsevier]

• Flow and heat transfer around a sphere under turbulent environment are studied using DNS and LES. • Incoming turbulence largely affects the fluid flow and heat transfer. • Increase of the free-stream turbulence shrinks the vortex formation region and increases drag coefficient. • Turbulence intensity increases the Nusselt number and its fluctuations, especially in the rear zone. • Turbulent heat fluxes in the wake are increased by ve times as turbulent intensity increases up to 10%. Free-stream turbulence is present in many engineering applications and is known to affect both bluff body aerodynamics and heat transfer. In this work, its effects on the heat transfer and the near wake behind a sphere are studied. To do this, direct and large-eddy simulations of the flow at the moderate Reynolds numbers of R e = 1000 and R e = 10 4 , with levels of incoming turbulence up to 10 % and a length scale of O (D) , D being the sphere diameter, are performed. At the Reynolds numbers under consideration, significant changes are observed. Incoming turbulence delays the separation of the laminar boundary layer from the sphere, while at the same time the drag coefficient and the Nusselt number are increased. The incoming level of turbulence also increases the momentum transfer from the surrounding fluid and energises the separated shear-layer. As a consequence, there is a shrinking of the recirculation zone which intensifies the heat transfer from the sphere and thus, the Nusselt number and its fluctuations, especially in the rear zone of the sphere. It is shown that free-stream turbulence increases the turbulent heat flux in the wake, with a larger entrainment of colder fluid from the surroundings, thus producing a faster decay of the temperature at larger levels of turbulence intensity. [ABSTRACT FROM AUTHOR]

• LES of VIV 2dof low mass ratio circular cylinder at subcritical Reynolds number are performed. • A detail description of the flow topology at the boundary layer and in the near wake is presented. • Taylor-Görtler (TG) vortices at the cylinder surface are reported for the first time. • TG vortices origin and characteristics are studied in detail. In this work, the three-dimensional structure of the boundary layer in the context of the vortex induced vibration of a circular cylinder is presented and investigated for the first time. Large-eddy simulations of a low mass ratio (m = 2.6) two-degrees of freedom circular cylinder at the subcritical Reynolds number R e = 5300 and zero damping (ζ = 0) for several reduced velocities of the system have been performed. A detailed description of the flow topology at the cylinder boundary layer and in the near wake for the three branches of structural response, i.e. the initial (I), super-upper (SU) and lower (L) branches, is presented. In the SU branch, the boundary layer becomes three-dimensional due to the emergence of streamwise vortices which are associated to the onset of a centrifugal instability that occurs twice every cycle. This is the first time a centrifugal instability in a freely vibrating system is reported. The streamwise structures with alternating vorticity, called here Taylor-Görtler vortices, are described and characterised. It is shown that their wavelength is in agreement with that of other centrifugal instabilities observed in forced sinusoidal oscillating cylinders. [ABSTRACT FROM AUTHOR]

In 2014 direct antiviral agents (DAA) became available for the treatment of chronic hepatitis C (CHC) for patients with severe fibrosis in France. Different algorithms were developed to identify special populations: migrants, prisoners, HIV+ patients, psychiatric patients, and drug users. [Extracted from the article]

New Direct Acting Antivirals (DAA) constituted a breakthrough innovation in chronic hepatitis C (CHC) treatments. A budget impact (BI) model was constructed to estimate the BI of CHC between 2014 and 2018 and to extrapolate long-term (up to 40y) direct and indirect costs for treated CHC patients. [Extracted from the article]

Reaction of 5,10-dihydrophenazine with two equivalents of Ph2PCl, in the presence of n-BuLi at −78 °C in thf gives Ph2PN(C6H4)(C6H4)NPPh2 (1)1Ph2PN(C6H4)(C6H4)NPPh2 (1). To a −78 °C thf (40 ml) solution of 5,10-dihydrophenazine (1.053 g, 5.78 mmol) was added dropwise a hexane solution of BuLi (4.8 ml, 2.5 mol dm−3, 12.08 mmol). The mixture was stirred at −78 °C for 1 h and another 30 min at room temperature. The reaction solution was cooled to −78 °C again and to it was added dropwise a solution of diphenylchlorophosphine (2.1 ml, 2.613 g, 11.84 mmol) in thf (10 ml) over 40 min. Stirring was continued for another 1 h at −78 °C and overnight at room temperature. The solution was evaporated to dryness in vacuo and dichloromethane (30 ml) was added. Lithium chloride, which precipitated, was removed by filtration under nitrogen and then the volatiles were evaporated in vacuo to leave a yellow solid. Yield: 2.896 g, 91%; Microanalysis: Found (Calcd) C 78.5 (78.5), H 5.1 (5.1), N 4.8 (5.1)%; 31P–{H} NMR (CDCl3): 61.0 (s) ppm; Selected IR data (KBr): ν(PN) 951 cm−1; FAB+ MS: m/z 550 [M], 551 [M + H+], 573 [M + Na+].1 which can be oxidised with selenium to Ph2P(Se)N(C6H4)(C6 H4)NP(Se)Ph2 (2)2Ph2P(Se)N(C6H4)(C6H4)NP(Se)Ph2 (2). To a dry and degassed toluene (10 ml) solution of selenium (0.029 g, 0.36 mmol) was added solid Ph2PN(C6H4)(C6H4)NPPh2 (0.100 g, 0.18 mmol). The solution was heated to reflux for ca. 2–3 h and allowed to cool to room temperature. The solution was evaporated to dryness in vacuo and the solid was dissolved in dichloromethane (2 ml). The dichloromethane solution was filtered through Celite and diethyl ether (20 ml) was added. The white product was collected by suction filtration and washed with diethyl ether (2 × 10 ml). Yield: 0.112 g, 88%; Microanalysis: Found (Calcd) C 60.3 (61.0), H 3.8 (4.0), N 3.8 (4.0)%; 31P–{H}NMR (CDCl3): 58.5 (s) ppm, 1J(77Se–31P) 832 Hz; selected IR data (KBr): ν(PN) 973 cm−1, ν(PSe) 565 cm−1; FAB+ MS: m/z 708 [M], 709 [M + H]+.2 or coordinated with Pt(II) in cis-[PtCl2{Ph2PN(C6H4)(C6H4)NPPh2}] (3)3cis-[PtCl2{Ph2PN(C6H4)(C6H4)NPPh2}] (3). To a dichloromethane (5 ml) solution of [PtCl2(cod)] (0.068 g, 0.18 mmol) was added solid Ph2PN(C6H4)(C6H4)NPPh2 (0.100 g, 0.18 mmol) and the colourless solution stirred for ca. 2–3 h. The solution was concentrated under reduced pressure to ca. 1 ml and diethyl ether (10 ml) added. The white product was collected by suction filtration and washed with diethyl ether (2 × 10 ml). Yield: 0.118 g, 80%; Microanalysis: Found (Calcd) C 53.0 (53.0), H 3.4 (3.5), N 3.3 (3.4)%; 31P–{H} NMR (CDCl3): 43.3 (s) ppm, 1J(195Pt–31P) 3854.6 Hz; selected IR data (KBr): ν(PN) 949 cm−1, ν(PtCl) 311 and 291 cm−1; FAB+MS: m/z 781 [M–Cl−], 839 [M + Na+], 816 [M].3 The structure of 3 reveals a severely distorted (non-planar) phenazine backbone. [Copyright &y& Elsevier]

The nonlinear giant magnetoimpedance (GMI) effect was explored as a highly sensitive sensing technology in 3D-printed magnetic encoded systems. Magnetic nanoparticles with low (magnetite, Fe 3 O 4) and high (Co ferrite, Co 0.7 Fe 2.3 O 4) magnetic remanence were embedded (10 wt%) in a polymeric matrix of Polylactic Acid (PLA) and Poly-ε-caprolactone (PCL) and extruded in magnetic filaments to be 3D printed by the Fused Deposition Modelling technique (FDM). Two different geometries were constructed namely, individual magnetic strips and fixed barcoded pieces. The stray magnetic fields generated by the magnetic nanoparticles were detected through the non-linear (second harmonic) GMI voltage using a soft magnetic CoFeSiB wire as the nucleus sensor. The decoding response was analyzed as a function of the magnetization remanence of the nanoparticles, the distance between the individual magnetic strips, and the position (height) of the GMI decoding sensor. It has been shown that modification of the net magnetization direction of each individual fixed strip within the barcode geometry is possible through the application of local external magnetic fields. This possibility improves the versatility of the 3D binary encoding system by adding an additional state (0 without nanoparticles, 1 or −1 depending on the relative orientation of the net magnetization along the strips) during the codifying procedure. [Display omitted] • Low & high remnant 3D printed bar magnets detected by non-linear GMI decoder. • Co ferrite particles detectable at larger heights sensor-piece. • Fe 3 O 4 particles allow better localized detection & simpler magnetization reversal. • Implementation of extra coded state "− 1" related to strip magnetization direction. • Control of the strip's direction allows reuse and magnetic reprogramming. [ABSTRACT FROM AUTHOR]

In this work, the feasibility of a magnetic binary encoding system using 3D printing technology is analyzed. The study has a double interest, that is, the possibility of printing a 3D piece that contains the codified information and the development of a system for its decoding. For this purpose, magnetic nanoparticles (magnetite Fe 3 O 4) were embedded in a polymeric matrix of Polylactic Acid (PLA) and Poly-ε-caprolactone (PCL). Similar to a conventional barcode, a rectangular piece with an alternating pattern of strips with absence (only polymer) and a 5 wt% of embedded magnetic nanoparticles was 3D printed employing the Fused Deposition Modelling technique (FDM). The information was decoded by means of a Giant Magnetoimpedance (GMI) sensor-based prototype, by scanning the surface of the piece and measuring the changes in the magnetic field. As sensor nucleus, an amorphous soft magnetic wire of nominal composition (Co 0.94 Fe 0.06) 72.5 Si 12.5 B 15 was employed. The decoding prototype incorporates a homemade electronic sensor interface that permits, at the time, the GMI sensor excitation and the subsequent signal conditioning to optimize its response. The output signal enables the detection of the magnetite nanoparticles and the magnetic decoding of the encoded information ("1" and "0", presence or absence of the magnetic nanoparticles, respectively). [Display omitted] • Fabrication of 3D printable filaments with embedded magnetic nanoparticles (Fe 3 O 4). • 3D printing of a functional piece with encoded information (barcode). • Decoding of hidden (no visible) codes using low-cost GMI-based decoder. [ABSTRACT FROM AUTHOR]

Supervised classification approaches try to classify correctly the new unlabelled examples based on a set of well-labelled samples. Nevertheless, some classification methods were formulated for binary classification problems and has difficulties for multi-class problems. Binarization strategies decompose the original multi-class dataset into multiple two-class subsets. For each new sub-problem a classifier is constructed. One-vs-One is a popular decomposition strategy that in each sub-problem discriminates the cases that belong to a pair of classes, ignoring the remaining ones. One of its drawbacks is that it creates a large number of classifiers, and some of them are irrelevant. In order to reduce the number of classifiers, in this paper we propose a new method called Decision Undirected Cyclic Graph. Instead of making the comparisons of all the pair of classes, each class is compared only with other two classes; evolutionary computation is used in the proposed approach in order to obtain suitable class pairing. In order to empirically show the performance of the proposed approach, a set of experiments over four popular Machine Learning algorithms are carried out, where our new method is compared with other well-known decomposition strategies of the literature obtaining promising results. [ABSTRACT FROM AUTHOR]

Class binarization strategies decompose the original multi-class problem into several binary sub-problems. One versus One (OVO) is one of the most popular class binarization techniques, which considers every pair of classes as a different sub-problem. Usually, the same classifier is applied to every sub-problem and then all the outputs are combined by some voting scheme. In this paper we present a novel idea where for each test instance we try to assign the best classifier in each sub-problem of OVO. To do so, we have used two simple Dynamic Classifier Selection (DCS) strategies that have not been yet used in this context. The two DCS strategies use K-NN to obtain the local region of the test-instance, and the classifier that performs the best for those instances in the local region, is selected to classify the new test instance. The difference between the two DCS strategies remains in the weight of the instance. In this paper we have also proposed a novel approach in those DCS strategies. We propose to use the K-Nearest Neighbor Equality (K-NNE) method to obtain the local accuracy. K-NNE is an extension of K-NN in which all the classes are treated independently: the K nearest neighbors belonging to each class are selected. In this way all the classes take part in the final decision. We have carried out an empirical study over several UCI databases, which shows the robustness of our proposal. [ABSTRACT FROM AUTHOR]

Abstract: A numerical study based on a two-fluid model to describe the fluid-dynamic behaviour of the two-phase flow inside ducts is presented. The discretization of the governing equations has been developed by means of the finite volume technique using a staggered mesh. A semi-implicit pressure-based method is used to couple the fluid conservation equations. Different empirical correlations have been used to evaluate the mass, momentum and energy exchanged through the interface, gas and liquid distribution in the tube, and other terms which appear in the conservation equations. These correlations are used depending on the flow regime map, which is function of the gas volume fraction and velocities. The instability of the two-fluid model due to the equations system is non-hyperbolic has been analyzed. Different two-phase flow cases have been solved by means of the method proposed in this paper. After a verification process to assess the quality of the numerical results obtained, the results are compared, when possible, with analytical solutions, and also with experimental data obtained by the authors. [Copyright &y& Elsevier]

Abstract: For the purpose of knowing the vermiculites which would have larger capability to retain contaminating substances heating commercial samples from different places have been identified and their thermal behaviour at several temperatures has been investigated by X-ray diffraction (XRD), electron microprobe, thermal analysis (TG and DTA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The commercial vermiculites can be divided into two types: type 1 (Sta. Olalla, Piauí and Goiás) with Mg2+ and K+ (<1) as the principal cations in the interlayer space, and type 2 (China E, China W, China G and Palabora) with K+ (approximately=or >1) and/or Na+ and/or Ca2+ with or without Mg2+ as the principal interlayer cations. The process of dehydration in situ with the temperature seems restricted to interlamellar water monolayers of 1-WLHS type-1 of vermiculites, without dehydration to a zero-water-layer-hydration state (0-WLHS) and the dehydroxylation starts at lower temperatures than in vermiculites of type 2. The maximum hydration state exhibited by the type-2 samples at ambient temperature was equal or lower than the monolayer hydrate, the dehydration process in situ with the temperature was slower and the dehydrated vermiculite coexists with a mica-like structure. The behaviour of vermiculites at elevated temperature examined in situ can be understood considering that the vermiculites constitute a complex system not necessarily in equilibrium and where kinetics plays an important role. Commercial vermiculites heated abruptly at 1000 °C during 1 min transform to mica-like or mica-like coexisting with enstatite, in contrast to the purest Sta. Olalla vermiculite, with only magnesium interlayer cations, which changes to enstatite. [Copyright &y& Elsevier]

Abstract: A new biosensor for detection of phenols, based on tyrosinase immobilization with alumina sol–gel on Sonogel-Carbon transducer, has been developed. The electrode was prepared using high energy ultrasounds directly applied to the precursors. The alumina sol–gel provided a microenvironment for retaining the native structure and activity of the entrapped enzyme and a very low mass transport barrier to the enzyme substrates. Phenols are oxidized by tyrosinase biosensor to form a detectable product, which was determined at −300mV vs. Ag/AgCl reference electrode. For phenol, the sensor exhibited a fast response which resulted from the porous structure and high enzyme loading of the sol–gel matrix. The linear range was from 5×10−7 M to 3×10−5 M, with a detection limit of 3×10−7 M. The stability of the biosensor was also evaluated. [Copyright &y& Elsevier]

Abstract: The present work describes the development of a modified platinum electrode for stripping voltammetric determination of silver. The deposition of films based on electropolymerisation of the monomer thiophene was carried out by cycling the potential towards positive values between 0 and 1.6V. The preconcentration process of silver ions was initiated on the surface of the modified electrode by complexing silver with polythiophene (PTH) when a negative potential (−0.5V) was applied; then the reduced products was oxidized by means of differential pulse stripping voltammetry and the peak was observed at 0.17V. Parameters such as pH, supporting electrolyte and number of electropolymerisation cycles were studied. A linear relation between current peak and concentration of Ag(I) was obtained in the range 0.07–1.0mgL−1. The detection limit for Ag(I) was evaluated to be 0.06mgL−1. The reproducibility was tested carrying out 11 measurements at different electrodes and the relative standard deviation was 1.5%. The interference of several metals was investigated and showed negligible effect on the electrode response. [Copyright &y& Elsevier]