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In the framework of the Broader Approach Agreement, Europe is involved in the design activities for the Japanese Tokamak JT-60SA, investigating, among several issues, the operation of the superconducting TF magnets and their subsystems, aimed at the reactor conceptual design definition. In particular, one of the main critical aspects to study is the heating of the conductor due to both direct component of energy deposited by neutrons and by secondary gamma generated during plasma operation, and heat generated by the radiation on casing and transferred to the winding pack. Indeed, the operating temperature and the relevant temperature margin (i.e. the operating safety margin) of the magnet will depend strongly on the heat loads and on the capability of the coolant to remove it. Furthermore, the heat power to the conductor will depend on several aspects, namely the thickness of insulating material, the mass flow rate of helium flowing in the conductors and its thermodynamic properties at operating conditions, and the layout of the superconductors constituting the winding. Moreover, a crucial aspect in the final design will be the presence and position of the casing cooling channels. In this paper a 2D sensitivity analysis of heat transfer from casing to winding pack with respect to cooling channels number and position is presented, based on the reference layout of the magnet. As a result, we evaluated the optimum number and positioning of cooling channels needed, as a trade-off between magnet operating limits and available cryogenic power and if, at limit, they could be even neglected in normal operation, keeping dwell-time within reasonable values.  相似文献   
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This paper presents the main features and results of the numerical and experimental studies that were carried out by ENEA in co-operation with ANSALDO and ISMES for the seismic verification of the Italian PEC fast reactor test facility. More precisely, the paper focuses on the wide-ranging research and development programme that has been performed (and recently completed) on the reactor building, the reactor-block, the main vessel, the core and the shutdown system. The needs of these detailed studies are stressed and the feed-backs on the design, necessary to satisfy the seismic safety requirements, are recalled. The general validity of the analyses in the framework of the research and development activities for nuclear reactors is also pointed out.  相似文献   
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In this paper, we have proposed and implemented a hardware-based security system, which executes RSA-based cryptography operations by using the PKCS#11 standard. It was implemented in C, VHDL and FPGAs and it is modular and easily adaptable to the future upgrades for the communication among machines and devices. Any cryptography algorithm can be used; however, in our project we only used the RSA as a case study. We did simulations and real tests that allowed verifying the correct behavior and execution of our project; we used the RSA with keys up to 512 bits. Real tests showed the transmission of ciphered data between our project (PKCS#11 and RSA) and a PC by using serial communication.  相似文献   
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Hybrid materials composed of superparamagnetic iron oxide nanoparticles (SPIONs) and lipid self-assemblies possess considerable applicative potential in the biomedical field, specifically, for drug/nutrient delivery. Recently, we showed that SPIONs-doped lipid cubic liquid crystals undergo a cubic-to-hexagonal phase transition under the action of temperature or of an alternating magnetic field (AMF). This transition triggers the release of drugs embedded in the lipid scaffold or in the water channels. In this contribution, we address this phenomenon in depth, to fully elucidate the structural details and optimize the design of hybrid multifunctional carriers for drug delivery. Combining small-angle X-ray scattering (SAXS) with a magnetic characterization, we find that, in bulk lipid cubic phases, the cubic-to-hexagonal transition determines the magnetic response of SPIONs. We then extend the investigation from bulk liquid-crystalline phases to colloidal dispersions, i.e., to lipid/SPIONs nanoparticles with cubic internal structure (“magnetocubosomes”). Through Synchrotron SAXS, we monitor the structural response of magnetocubosomes while exposed to an AMF: the magnetic energy, converted into heat by SPIONs, activates the cubic-to-hexagonal transition, and can thus be used as a remote stimulus to spike drug release “on-demand”. In addition, we show that the AMF-induced phase transition in magnetocubosomes steers the realignment of SPIONs into linear string assemblies and connect this effect with the change in their magnetic properties, observed at the bulk level. Finally, we assess the internalization ability and cytotoxicity of magnetocubosomes in vitro on HT29 adenocarcinoma cancer cells, in order to test the applicability of these smart carriers in drug delivery applications.  相似文献   
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In this work, the composition of fatty acids and the oxidative stability of the oil from Raphanus sativus L. var. oleiferus Metzg. are presented and analyzed with the Rancimat method, and by absorption and molecular fluorescence spectroscopy. The gas chromatography showed that the content of unsaturated fatty acids was 90.27 ± 6.10 %, with a predominance of oleic (C 18:1), linoleic (C 18:2), erucic (C 22:1), linolenic (C 18:3) and eicosenoic (C 20:1) acids. The induction period determined by the Rancimat method was 48.0 ± 1.0 h. In addition, the thermal degradation of the oil was monitored through its acid value, density, UV–Vis absorption and molecular fluorescence, and here we show the potential applicability of emission spectroscopy for R. sativus oil oxidation studies.  相似文献   
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The authors analyse the results of direct (cervical, urethral, tubal) and serological research of Chlamydia trachomatis in a sample population of 420 women undergoing celioscopy due to sterility and pelvic pain, paying particular attention to a group of 193 who were found to be suffering from PID (acute, sequelae). In terms of absolute numbers the correlation between chlamydial contact-PID-sterility is confirmed, whereas in an analysis of the levels of direct positivity it is only significant for acute PID, and in cases of sequelae and in sterility with chronic infection with or without tubal damage the direct identification of Chlamydia trachomatis does not differ much from controls. Salpingo-peritoneal isolation was found to be completely lacking in significance.  相似文献   
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