Roberto Giannantonio

Design and characterization of high capacity nonevaporable getter pumps embedded inside the interaction regions of DAΦNE

The DAΦNE Φ-factory is a twin-ring 510 MeV e+e- collider facility under commissioning at INFN-LNF in Frascati. With a stored beam current of 5.3 A, a mean pressure of 1.3×10−9 mbar is required in each ring. For the KLOE interaction region, where a mean pressure of the order of 1.3×10−10 mbar is required, an embedded nonevaporable getter (NEG) pump with a CapaciTorr®-type structure was chosen mainly because of the unavailability of room for the installation of lumped pumps and to take maximum advantage of the sorption capability of the NEG pump for CO in the UHV operating conditions of the machine. A NEG pumping system of the kind discussed in this article seemed to be particularly suitable for the KLOE experiment, where limited servicing and high reliability is required. In this article we report on the design and characterization of both the first pump prototype, fitted with St-172 NEG alloy and the final pump version, where St-185 NEG alloy was used.

Pumping characteristics of metal films in a vacuum glass vessel: Experimental and theoretical issues

The evaluation of the pumping characteristics of metallic films deposited onto glass surfaces in a vacuum environment is a very important issue for several industrial and research applications. Many years ago, an optimized experimental setup and method were defined to measure the pumping characteristics of barium films inside cathode ray tubes (CRTs). [P. della Porta and F. Ricca, Advances in Vacuum Science and Technology (Pergamon, New York, 1960), Vol. II, p. 661 and P. della Porta and L. Michon, Vacuum 15, 536 (1965)]. However, some technological limitations, related both to the particular experimental configuration and to the method used, prevented the possibility of extending this approach to a more general case, including adsorbing materials different from barium, deposited onto surfaces having a geometry different from that of a CRT. The progress in vacuum technology makes it possible today to use a large variety of components to assemble an experimental vacuum apparatus. Moreover, the availability...

Photo-active integrated getters for stable dye-sensitized solar cells

Linde Type A with Na cation (LTA-Na) nanozeolite-based TiO2 photoanodes have been implemented in dye-sensitized solar cells introducing the concept of an integrated getter. These innovative structures improve the device stability thanks to their ability to neutralize the moisture effect, while also acting as active scattering centers.

Organisational ambidexterity in the search phase of the innovation process. Evidence from a leading case study

How firms succeed in reconciling the exploitation of existing knowledge with the exploration of new possibilities is an open question in the literature and it represents the core of our paper, the aim of which is to explore how firms have actually achieved ambidexterity capability. In order to do so, we decided to focus on the very early phase of the process where firms search for new ideas with which to renew themselves. In particular, we analysed the search phase of a highly innovative technology-based company by investigating the structural design choices combined with the presence of specific roles and searching practices. The results show how exploration and exploitation can actually be achieved simultaneously and maintained through a multilevel approach that integrates both the operational and the strategic levels. Our findings, thus, contribute to the organisational ambidexterity literature by proposing a first interpretative model for dealing with ambidexterity in the search phase of the innovation process.