Results of simulations of stability and quench behavior for pulsed tests of the ENEA 12T Nb3Sn CICC coil

In the ENEA Frascati Laboratory a facility is being assembled to test the ENEA Nb₃Sn CICC coil in pulsed regimes. The characteristics of the coil (dimensions, cable-in-conduit conductor, strand designed for use in variable field) are such to make these tests of primary importance to predict the behaviour of the ITER (International Thermo-nuclear Experimental Reactor) Central Solenoid Model Coil, which will be built in the next two years. In particular, the stability and quench behaviour of the coil will be tested and compared to the predictions of the thermo-hydraulic analysis code SARUMAN. Other important parameters will be the ramp rate limination, the limiting current and the conductor losses. Several testing scenarios (ramp up and discharge) are described and the present status of testing programme definition is given, together with the associated analyses.     

Necessary exponential stability conditions for linear periodic time‐delay systems

Exponential stability necessary conditions for linear periodic time‐delay systems are presented. They are obtained with the help of new properties of the Lyapunov matrix in the framework of Lyapunov–Krasvoskii functionals of complete type. An academic example illustrates our results. Copyright © 2016 John Wiley & Sons, Ltd.     

Anionenaustausch in gemischten lösungsmitteln – einwertige anionen am anionenaustauscher wofatit SBK

The equilibrium coefficients and relative affinities of 10 monovalent anions on the strongly basic anion-exchanger resin Wofatit SBK were determined in batches by the conductivity method in water-miscible solvents (H₂O: org. solvent = 20:80) methanol, ethanol, 2-propanol, acetone, dimethylsulfoxide and acetonitrile. The measured values are investigated with respect to their practical applicability and are discussed in relation to values measured in pure aqueous medium.     

Unsaturated polyester

Summary The polyesterification reaction between maleic anhydride and 1,5-pentanediol, using p-toluenesulphonic acid as catalyst, was carried out. The material was characterized spectroscopically and its molecular weight measured. Besides isomerization of maleate to fumarate, some sort of intramolecular ring closure between polymer end groups may be occurring, since there is little agreement between molecular weight measurements by end group analysis and gel permeation chromatography, and very weak absorption is observed for hydroxyl group.     

Unsaturated polyesters

Summary The polymerization of maleic anhydride and 1,3-propylene glycol was carried out using p-toluenesulphonic acid as catalyst. The resulting material has been characterized by ir and H¹nmr spectroscopy, end group analysis and gel permeation chromatography. The percentage isomerization of maleate to fumarate has been correlated with the extension of polycondensation and the steric hindrance between the condensed functional groups.     

The drying of barley malt in the spouted bed dryer

The drying of barley malt was studied in a batch spouted-bed dryer using three inlet air temperatures (60, 80 and 90°C) and three initial masses of malt (25, 30 and 35 kg). One of the conclusions was that the drying can be conducted at higher temperatures than in the classical equipment. A general correlation was obtained through the use of reduced moisture and reduced time. A mathematical model which assumes only an external resistance of diffusion or heat transfer does not apply. Also, the model based on internal water diffusion does not predict the results. A new semi-empirical model based on semi-permeable membranes has been proposed. A method of using batch laboratory drying data to predict the performance of continuous spouted-bed driers has been outlined.     

Characterization of polyurethane resins by FTIR,TGA, and XRD

Fourier Transformed Infrared Spectroscopy, Thermogravimetric Analysis, and X‐ray Diffractometry have been used to investigate the rigid, semi rigid, and soft polyurethane (PU) forms, which were developed by the Group of Analytic Chemistry and Technology of Polymers ‐ USP ‐ São Carlos. The –NCO/–OH ratios were 0.6, 0.5, and 0.3% for rigid, semi rigid, and soft PUs, respectively, showing that different ratios cause differences in thermal behaviors and crystalline structures of the synthesized PU resins. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Stakeholder management influence on trust in a project: A quantitative study

This article aims to analyze the influence of stakeholder management on trust in project environments. Data was collected from 130 project professionals in companies from several national and multinational segments operating in Brazil. PLS-PM was applied for treatment and for data analysis. The results show that the relational stakeholder management influence on the three types of trust is relevant and significant. Therefore, it is important that the project manager not fail to consider actions such as communication with empathy as of the beginning of the project.     

On the invariant reactions in the Mo-rich portion of the Mo-Si system

The Mo-Si system presents two invariant reactions (eutectic and peritectic) in the Mo-rich region; these reactions involve the Liquid, Mo_ss, Mo₃Si, and Mo₅Si₃ phases. The results presented in the literature show disagreement about the specific reactions, with two proposals being reported: (1) L + Mo_ss ⇔ Mo₃Si and L ⇔ Mo₃Si + Mo₅Si₃; and (2) L + Mo₅Si₃ ⇔ Mo₃Si and L ⇔ Mo_ss + Mo₃Si. In order to contribute to this subject, we have produced several Mo-Si alloys (21 to 29 at.% Si) via arc melting and evaluated the as-cast microstructures through x-ray diffraction (XRD), scanning electron microscope/backscattered electron image (SEM/BSEI), and energy dispersive x-ray analysis (EDS). The primary phases identified in the different samples were Mo_ss, Mo₃Si, and Mo₅Si₃. The results have indicated clearly the existence of a eutectic reaction involving the phases Mo₃Si and Mo₅Si₃, confirming the existence of the L + Mo_ss ⇔ Mo₃Si and L ⇔ Mo₃Si + Mo₅Si₃ invariant reactions. In addition, alloys with composition 26 at.% Si and 27 at.% Si presented Mo₃Si and Mo₅Si₃ as primary phases, respectively, indicating that the liquid eutectic composition is located between those values.