4,751 research outputs found
Selective gold and palladium adsorption from standard aqueous solutions
The intensive exploitation of resources on a global level has led to a progressive depletion of mineral reserves, which were proved to be insufficient to meet the high demand for high-technological devices. On the other hand, the continuous production of Waste from Electrical and Electronic Equipment (WEEE) is causing serious environmental problems, due to the complex composition of WEEE, which makes the recycling and reuse particularly challenging. The average metal content of WEEE is estimated to be around 30% and varies depending on the manufacturing period and brand of production. It contains base metals and precious metals, such as gold and palladium. The remaining 70% of WEEEs is composed of plastics, resins, and glassy materials. The recovery of metals from WEEEs is characterized by two main processes well represented by the literature: Pyrometallurgy and hydrometallurgy. Both of them require the pre-treatment of WEEEs, such as dismantling and magnetic separation of plastics. In this work, the selective adsorption of precious metals has been attempted, using copper, gold, and palladium aqueous solutions and mixtures of them. A screening on different adsorbent materials such as granular activated carbons and polymers, either as pellets or foams, has been performed. Among these, PolyEther Block Amide (PEBA) was elected as the most performing adsorbent in terms of gold selectivity over copper. Spent PEBA has been then characterized using scanning electron microscope, coupled with energy dispersive spectroscopy, demonstrating the predominant presence of gold in most analyzed sites, either in the pellet or foam form
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A Directory Service for the CERN PS/SL Java Programming Interface
The CERN PS and SL accelerator control groups developed a common application programming interface (API) in Java [1]. Part of this API is a directory service that provides information about the underlying hardware and software. With this information it is possible to write generic programs that do general actions on lists of devices without hard coding of device names. And, starting from a device name, full details about related devices, the device itself and its class and properties, can be obtained, including the meaning of bits and bitpatterns in status words. The interface definition is independent of any implementation but a reference implementation is provided using Java Database Connectivity (JDBC) against a set of tables in a relational database. Data from very different systems can be brought together and presented in a uniform way to the user. The full potential of the directory service is reached when it is used in software components (Java Beans)
Resistance-based probabilistic design by order statistics for an oil and gas deep-water well casing string affected by wear during kick load
Deep-water wells for oil and gas extraction make structural components, such as casing and tubing, work in extremely harsh environmental conditions that accelerate component degradation and increase failure probability. Therefore, it is important to properly design casing strings under these operative circumstances (Baraldi et al., 2012)
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The CERN PS/SL Controls Java Application Programming Interface
The PS/SL Convergence Project was launched in March 1998. Its objective is to deliver a common controls infrastructure for the CERN accelerators by year 2001. In the framework of this convergence activity, a project was launched to develop a Java Application Programming Interface (API) between programs written in the Java language and the PS and SL accelerator equipment. This Java API was specified and developed in collaboration with TJNAF. It is based on the Java CDEV [1] package that has been extended in order to end up with a CERN/TJNAF common product. It implements a detailed model composed of devices organised in named classes that provide a property-based interface. It supports data subscription and introspection facilities. The device model is presented and the capabilities of the API are described with syntax examples. The software architecture is also described
Carcinoid heart failure in a duodenal neuroendocrine tumor: role of cardiac surgery in a challenging patient and brief review of the literature
Therapeutic sequences in patients with grade 1â2 neuroendocrine tumors (NET): an observational multicenter study from the ELIOS group
Purpose: Many different treatments are suggested by guidelines to treat grade 1â2 (G1âG2) neuroendocrine tumors (NET). However, a precise therapeutic algorithm has not yet been established. This study aims at identifying and comparing the main therapeutic sequences in G1âG2 NET. Methods: A retrospective observational Italian multicenter study was designed to collect data on therapeutic sequences in NET. Median progression-free survival (PFS) was compared between therapeutic sequences, as well as the number and grade of side effects and the rate of dose reduction/treatment discontinuation. Results: Among 1182 patients with neuroendocrine neoplasia included in the ELIOS database, 131 G1âG2 gastroenteropancreatic, lung and unknown primary NET, unresectable or persistent/relapsing after surgery, treated with â„2 systemic treatments, were included. Four main therapeutic sequences were identified in 99 patients: (A) somatostatin analogs (SSA) standard dose to SSA high dose (n = 36), (B) SSA to everolimus (n = 31), (C) SSA to chemotherapy (n = 17), (D) SSA to peptide receptor radionuclide therapy (PRRT) (n = 15). Median PFS of the second-line treatment was not reached in sequence A, 33 months in sequence B, 20 months in sequence C, 30 months in sequence D (p = 0.16). Both total number and severity of side effects were significantly higher in sequences B and C than A and D (p = 0.04), as well as the rate of dose reduction/discontinuation (p = 0.03). Conclusions: SSA followed by SSA high dose, everolimus, chemotherapy or PRRT represent the main therapeutic sequences in G1âG2 NET. Median PFS was not significantly different between sequences. However, the sequences with SSA high dose or PRRT seem to be better tolerated than sequences with everolimus or chemotherapy
Hydraulic characterization of the full scale mock-up of the demo divertor outer vertical target
In the frame of the pre-conceptual design activities of the DEMO work package DIV-1 âDivertor Cassette Design and Integrationâ of the EUROfusion program, a mock-up of the divertor outer vertical target (OVT) was built, mainly in order to: (i) demonstrate the technical feasibility of manufacturing procedures; (ii) verify the hydraulic design and its capability to ensure a uniform and proper cooling for the plasma facing units (PFUs) with an acceptable pressure drop; and (iii) experimentally validate the computational fluid-dynamic (CFD) model developed by the University of Palermo. In this context, a research campaign was jointly carried out by the University of Palermo and ENEA to experimentally and theoretically assess the hydraulic performances of the OVT mock-up, paying particular attention to the coolant distribution among the PFUs and the total pressure drop across the inlet and outlet sections of the mock-up. The paper presents the results of the steady-state hydraulic experimental test campaign performed at ENEA Brasimone Research Center as well as the relevant numerical analyses performed at the Department of Engineering at the University of Palermo. The test facility, the experimental apparatus, the test matrix and the experimental results, as well as the theoretical model, its assumptions, and the analyses outcomes are herewith reported and critically discussed
Thermofluid-dynamic assessment of the EU-DEMO divertor single-circuit cooling option
Until 2019, the thermo-hydraulic development of the EU-DEMO divertor was based on the âdouble-circuitâ concept, in which two independent cooling circuits served by two different Primary Heat Transfer Systems were used to cool the Plasma-Facing Components (PFC) and the Cassette Body (CB). During the Divertor Final Design Review Meeting, held in May 2020, the possibility to adopt a single cooling circuit to serve both components was suggested. This new cooling circuit was originally conceived with the aim of simplifying remote maintenance, with potential benefits for some aspects of safety and balance of plant design and integration. During the years from 2020 to 2022, in the framework of the Work Package DIV 1 - âDivertor Cassette Design and Integrationâ of the EUROfusion action, University of Palermo and ENEA carried out a research campaign focussed on the preliminary thermofluid-dynamic assessment of this new concept, highlighting its strengths and weaknesses. The research campaign was carried out following a theoreticalâcomputational approach based on the finite volume method and adopting the commercial computational fluid-dynamic code ANSYS-CFX. The steady-state thermal-hydraulic performances of the single-circuit DEMO divertor concept were assessed in terms of coolant pressure drop and flow velocity distribution, mainly in order to check coolant aptitude to provide a uniform and effective cooling to CB, shielding liner, reflector plates, PFCs and the newly introduced neutron shields to improve the shielding of the vacuum vessel. Moreover, the margin against critical heat flux distributions among the plasma-facing channels were assessed by adopting appropriate correlations, to check the compliance with the applicable constraints. Models, loads and boundary conditions assumed for the analyses are herewith reported and critically discussed, together with the main results obtained
C28Sequencing cabazitaxel and new generation hormonal treatments in metastatic castration resistant prostate cancer patients after first line docetaxel: a retrospective analysis
Clinical and molecular features of epidermal growth factor receptor (Egfr) mutation positive nonâsmallâcell lung cancer (nsclc) patients treated with tyrosine kinase inhibitors (tkis): Predictive and prognostic role of coâmutations
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