ANDRE LUIS LAPOLLI
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Artigo IPEN-doc 24130 Control system and automation of the spectrum acquisition for a perturbed gamma-gamma angular correlation spectrometer2017 - STACHOWSKI, ADEMIR F.A.; LAPOLLI, ANDRE L.; CARBONARI, ARTUR W.; SAXENA, RAJENDRA N.This work reports results from the automation of data acquisition for a gamma-gamma perturbed angular correlation (PAC) spectrometer located in the hyperfine interactions laboratory (LIH) of IPEN. A PAC spectrometer comprises usually four scintillation detectors (BaF3 for example) and carries out time measurements from gamma rays of any two combinations of detectors in coincidence. Gamma rays come from the decay of probe nuclei embedded into the material to be studied. Measurements are generally performed as a function of temperature. The fourth-detectors PAC spectrometer was automated in Java language because it is a multiplatform and object oriented programming language, having, therefore, portability and longer lifetime due to the ease of implementation of peripherals. Finally, the software has a friendly and intuitive interface with the user being able to operate the hardware manually or automatically with time acquisitions up to 100 consecutive hours. Before each acquisition, the software sets the temperature, waits for temperature stability and records data in different files. Moreover, the software also saves in a file all information of relevant parameters during acquisition.Artigo IPEN-doc 24129 A new 124Xe irradiation system for 123I routine production at the 30 MeV IPEN-CNEN/SP cyclotron2017 - LAPOLLI, ANDRE L.; BARCELLOS, HENRIQUE; MATSUDA, HYLTON; SUMIYA, LUIZ C. do A.; JUNQUEIRA, FERNANDO de C.Since 2001 the Nuclear and Energy Research Institute (IPEN/CNEN-SP, Brazil) has produced about 2.5 mCi/mAh of 123I weekly using a manual irradiation system fully developed by its researchers. Ultrapure 123I has been produced and distributed to hospitals and clinics where several diagnostic imaging procedures are done for thyroid, brain and cardiovascular functions. Due to the short half-life and emission of low-energy photons, this radioisotope becomes suitable for diagnosis in children. Currently IPEN researchers are involved in the development of a new fully automated irradiation system dedicated to 123I routine production employing enriched xenon gas (124Xe) as the target material. This new system consists of a target port, a water and a helium cooling system, a cryogenic system, an electric power system, a control and process monitoring unit composed of a supervisory software connected to a Programmable Logic Controller (PLC) via personal computer. In this new concept, there is no need for human interference during radioisotope production, reducing the possibility of eventual failures or incidents involving radioactive material. In this way, with this new system, a specific yield of approximately 3.5 mCi/mAh per irradiation is expected and this will meet a large part of the national demand for this important radioisotope. In the present work will be presented all the technical and constructive aspects of this new system as well as the results obtained in the irradiation of tests.Artigo IPEN-doc 24100 Automated spectrometer interface for measurement of short half-life samples for neutron activation analysis2017 - LAPOLLI, ANDRE L.; SECCO, MARCELLO; GENEZINI, FREDERICO A.; ZAHN, GUILHERME S.; MOREIRA, EDSON G.In this paper a source positioning system was developed, based on a HPGe detector coupled to a Canberra DAS 1000 data acquisition system and Canberra’s GENIE2K software and libraries. The system is composed of a step motor coupled to an Arduino Uno microcontroller, which is programmed using C language to allow for a source-detector distance between 0.3 and 20 cm - both components are coupled to a PC computer using the USB interface. In order to allow automated data acquisition, two additional pieces of software were developed. The first one, a Human-Machine Interface (HMI) programmed in Visual Basic 6, allows the programming and monitoring of the data acquisition process, and the other, in REXX language, controls the data acquisition process in the background. The HMI is user-friendly and versatile, so that the even rather complex data acquisition processes may be easily programmed. When the experiment scheme is saved, two files are created and used by the REXX code to control the acquisition process so that the data acquisition is automatically stopped and saved after a user-defined time, then the source is repositioned and data acquisition is cleared and restarted. While in the present stage the system only offers three distinct source positions, finer source-position adjusting is under development. In its present configuration the system has been tested for stability and repeatability in all three positions, with an excellent performance.Artigo IPEN-doc 24038 Validity studies among hierarchical methods of cluster analysis using cophenetic correlation coefficient2017 - CARVALHO, PRISCILLA R.; MUNITA, CASIMIRO S.; LAPOLLI, ANDRE L.The literature presents many methods for partitioning of data base, and is difficult choose which is the most suitable, since the various combinations of methods based on different measures of dissimilarity can lead to different patterns of grouping and false interpretations. Nevertheless, little effort has been expended in evaluating these methods empirically using an archaeological data base. In this way, the objective of this work is make a comparative study of the different cluster analysis methods and identify which is the most appropriate. For this, the study was carried out using a data base of the Archaeometric Studies Group from IPEN-CNEN/SP, in which 45 samples of ceramic fragments from three archaeological sites were analyzed by instrumental neutron activation analysis (INAA) which were determinated the mass fraction of 13 elements (As, Ce, Cr, Eu, Fe, Hf, La, Na, Nd, Sc, Sm, Th, U). The methods used for this study were: single linkage, complete linkage, average linkage, centroid and Ward. The validation was done using the cophenetic correlation coefficient and comparing these values the average linkage method obtained better results. A script of the statistical program R with some functions was created to obtain the cophenetic correlation. By means of these values was possible to choose the most appropriate method to be used in the data base.Artigo IPEN-doc 22523 Design of electronic system with simultaneous registering of pulse amplitude and event time applied to 4'pi''beta'-'gama' coincidence method2008 - TOLEDO, FABIO de; BRANCACCIO, FRANCO; LAPOLLI, ANDRE; DIAS, MAURO da S.Artigo IPEN-doc 10576 Study of magnetism in GDTIN(T=NI,PD,CU) compounds by perturbed gamma-gamma angular correlation spectroscopy2005 - LEITE, D.M.T.; LAPOLLI, A.L.; CARBONARI, A.W.; SAXENA, R.N.; MESTNIK FILHO, J.Artigo IPEN-doc 19260 Investigation of hyperfine interactions in DNA nitrogenous bases using perturbed angular correlation spectroscopy2013 - SILVA, ANDREIA dos S.; CARBONARI, ARTUR W.; LAPOLLI, ANDRE L.; SAXENA, RAJENDRA N.; SAITOVITCH, HENRIQUEArtigo IPEN-doc 19437 Development of a multiplatform and multi parameter data acquisition interface2013 - LAPOLLI, ANDRE L.; ZAHN, GUILHERME S.Artigo IPEN-doc 19433 Development and installation of an automatic sample changer for neutron activation analysis2013 - DOMIENIKAN, CLAUDIO; LAPOLLI, ANDRE L.; SCHOUERI, ROBERTO M.; MOREIRA, EDSON G.; VASCONCELLOS, MARINA B.A.Artigo IPEN-doc 15160 Application of perturbed angular correlation spectroscopy in IgG immunoglobulins2009 - SILVA, A.S.; AMARAL, A.A.; LAPOLLI, A.L.; CARBONARI, A.W.
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