PAULO ROBERTO RELA
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Resumo IPEN-doc 24746 Chromatographic analysis of irradiated medicinal herbs2001 - KOSEKI, PAULA M.; RELA, PAULO R.; VILLAVICENCIO, ANNA L.C.H.Introduction: Nowadays the interest in phytotherapeutics is increasing; therefore the consumer attention to the medicinal active plants is growing. The rich Brazilian flora, represents more than 20% of the plant species know in the world as raw materials for pharmaceutical preparations. Since the last decade microbiological decontamination of medicinal herbs by irradiation has been carried out and presented in many scientific articles. The microbial contamination in these raw plant materials is the issue of several studies, which propose appropriate techniques for the reduction of micro-organisms. One of these techniques is radiation processing by gamma source industrial plants. Other is the utilisation of accelerators. In order to safeguard consumers, treatment by ionizing radiation is allowed now in Brazil to medicinal herbs and pharmaceutical products. The radiation process is known as safe for a large variety of products and applications as well as a effective in the reduction of pathogenic micro-organisms. The aim of our study is observe if flavonoids and alkaloids will be influenced by irradiation. Experimental: Samples - Local herbs companies in Sao Paulo, Brazil, provided dehydrated samples of Rhamnus purshiana D.C. and Paulinia cupana Kunth. Irradiation. The powdered samples were irradiated in on plastic package in a electron beam accelerator facility of Radiation Dynamics Inc., USA (E=1,5 MeV, l=25 mA, installed in IPEN Sao Paulo, Brazil. The irradiation doses were 10,20 and 30 kGy at room temperature. The thickness of samples was less than 0,5 cm. Sample analysis -flavonoids and alkaloids analysis was performed in a Thin Layer Chromatography according to Wagner (1995). Results and discussion: No alterations in the flavonoids and alkaloids, after irradiation treatment in that herbs was observed. Chromatographic analysis of the different extracts irradiated at increasing doses indicated that there were no great differences in the chemical constitution of the herbs. The extracts, presented no change in the color increasing the irradiation doses (results are similar in other herbs extracts) as showed in the absorption peaks. The samples showed similar curves, presenting no changes in the chemical compounds. Pharmacological activity of medicinal herbs has been found satisfactory after treatment by high doses radiation.Artigo IPEN-doc 28280 Studies of hydrothermal quartz from Ametista do Sul treated with gamma radiation2021 - ENOKIHARA, CYRO T.; GUTTLER, RAINER A.S.; RELA, PAULO R.Artigo IPEN-doc 27880 Comparative analysis of quartz treated with gamma radiation originated from the hydrothermal geodes of the Paraná Basin, with quartz generated in the hydrothermal veins of Serra do Espinhaço2021 - ENOKIHARA, C.T.; SCHULTZ-GUTTLER, R.A.; RELA, P.R.In Brazil, hydrothermal quartz may be found in the geodes of the basaltic rocks of the Paraná Basin and in the vein systems of quartzites of the Serra do Espinhaço. The quartz of hydrothermal origin of the Paraná Basin contains a great amount of structurally bound water in the form of molecular water, silanol, hydroxyl and abundant growth defects that are responsible for the green color formed by irradiation. To register the influence of water in the formation of the green color in the quartz of the Paraná Basin, quartz samples from the following regions were analyzed: Artigas, located in the Paraná Basin, Curvelo and Brejinho located in Serra do Espinhaço. The quartz from Artigas, formed at low temperature, has high concentration of molecular water and silanol and a greater amount of Fe than Al. The quartz from Curvelo with Al, but, without water molecular and silanol was formed by intermediate temperature and the quartz from Brejinho has very little Al, Fe and a small silanol and molecular water content. To characterize these samples, ICP, NAA, and NIR-FTIR spectroscopic measurements have been taken together with water loss techniques. The analysis by FTIR spectrometry of Artigas quartz samples shows strong absorptions of H2O and Si-OH, respectively, near the regions of 5300 cm-1 and 4500 cm-1. This content of molecular water and silanol in hydrothermal quartz of Artigas is responsible for the formation of NBOHC defects that produce, by gamma radiation, the green color.Artigo IPEN-doc 26739 Gamma radiation of quartz from Entre Rios (SC) and Quaraí (RS)2019 - ENOKIHARA, C.T.; SCHULTZ-GUTTLER, R.A.; RELA, P.R.The availability of gamma ray irradiators in Brazil increased the possibilities of the treatment of gemstones for color enhancement. One of the minerals with very high potential for these treatments is the quartz, a very widespread mineral with many colored commercial varieties. There is a specific variety of quartz in nature, showing a green color that may be produced artificially, by gamma radiation (60Co). In Brazil, the widely scattered geode occurrence from Quaraí, at Brazil southernmost location up to Uberlandia, in Minas Gerais, is one of these events. Quartz from these occurrences have been formed by strong hydrothermal activities. Hence, many quartz crystals showed a very fast growth occurrence, facilitating the formation of consequent defects and the uptake of water under the form of micro inclusions, molecular water, silanol (Si-OH) and OH. In the present work, the material analyzed is from hydrothermal regimes located near the towns Entre Rios and Quaraí. To characterize these materials, analyses have been made by ICP, NAA, electron microscopy, water loss techniques plus UV-VIS and NIR-FTIR spectroscopic measurements. Silanol complexes have been found by radiation, due to gamma rays forming the color center NBOHC (Non-Bonding Oxygen Hole Center), showing absorption between 590 to 620 nm and leaving a transmission window at about 550nm, responsible for the green color. The spectroscopic water determination showed less molecular water (up to 2300 ppm, per weight), probably due to remaining silanol complexes. The water content, with up to 3200 ppm by weight, exceeds the amount of charge balancing cations (Fe, Al, Li).Artigo IPEN-doc 26270 Comparative analysis of quartz treated with gamma radiation originated from the hydrothermal geodes of the Paraná Basin (Artigas-Uruguay region), with quartz generated in the hydrothermal veins of Serra do Espinhaço (Curvelo-MG and Brejinho-BA regions)2019 - ENOKIHARA, CYRO T.; SCHULTZ-GUTTLER, RAINER A.; RELA, PAULO R.In Brazil, hydrothermal quartz may be found in the geodes of the basaltic rocks of the Paraná Basin and in the vein systems of quartzites of the Serra do Espinhaço. The quartz of hydrothermal origin of the Paraná Basin contains a great amount of structurally bound water in the form of molecular water, silanol, hydroxyl and abundant growth defects that are responsible for the green color formed by irradiation. To register the influence of water in the formation of the green color in the quartz of the Paraná Basin, quartz samples from the following regions were analyzed: Artigas, located in the Paraná Basin, Curvelo and Brejinho located in Serra do Espinhaço. The quartz from Artigas, formed at low temperature, has high concentration of molecular water and silanol and a greater amount of Fe than Al. The quartz from Curvelo with Al, but, without water molecular and silanol was formed by intermediate temperature and the quartz from Brejinho has very little Al, Fe and a small silanol and molecular water content. To characterize these samples, ICP and NIR-FTIR spectroscopic measurements have been taken, together with water loss techniques and color stability, by UV treatment and heating. The analysis by FTIR spectrometry of Artigas quartz samples shows strong absorptions of H2O and Si-OH, respectively, near the regions of 5300 cm-1 and 4500 cm-1. This content of molecular water and silanol in hydrothermal quartz of Artigas is responsible for the formation of NBOHC defects that produce, by gamma radiation, the green color.Artigo IPEN-doc 24183 Gamma radiation of quartz from Entre Rios (SC) and Quaraí (RS)2017 - ENOKIHARA, CYRO T.; SCHULTZ-GUTTLER, RAINER A.; RELA, PAULO R.The availability of gamma ray irradiators in Brazil increased the possibilities of treatments of gemstones for color enhancements. One of the minerals with a very high potential of these treatments is quartz, a very widespread mineral with many colored commercial varieties. A specific variety of quartz showing a green color in nature or induced artificially by radiation gamma (60Co) is quite rare. In Brazil the widely scattered geode occurrences along a 600 km stretch from Quaraí at Brazil southernmost tip to Uberlandia in Minas Gerais is one of these. Quartz from these occurrences have been formed by strong hydrothermal activities. That way much quartz crystals showed a very fast growth history facilitating the formation of growth defects and the uptake of water in form of micro inclusions, molecular water, silanol (Si-OH) and OH. In the present work the material analyzed is from hydrothermal regimes located near the towns Entre Rios (SC) and Quaraí (RS). To characterize these materials analyses have been made by ICP, NAA, electron microscopy, water loss techniques and UV-VIS and NIR-FTIR spectroscopic measurements. Silanol complexes are found, which by radiation due to gamma rays form the color center NBOHC (Non-Bonding Oxygen Hole Center), showing absorption between 590 to 620 nm and leaving a transmission window at about 550nm, responsible for the green color. The spectroscopic water determination showed less molecular water (up to 2300 ppm by weight), probably due to remaining silanol complexes.The water content with up to 3200 ppm by weight exceeds the amount of charge balancing cations (Fe, Al, Li).Resumo IPEN-doc 23058 Multipurpose gamma-irradiator and mobile unit with an electron beam accelerator developed in Brazil2017 - CALVO, W.A.P.; DUARTE, C.L.; SOMESSARI, S.L.; SPRENGER, F.E.; COSTA, F.E.; FEHER, A.; SALVADOR, P.A.V.; OMI, N.M.; SILVA, L.G.A.; LAINETTI, F.F.; RELA, P.R.; SAMPA, M.H.O.Radiation processing technology for industrial and environmental applications has been developed and used worldwide in the fields of water treatment, advanced materials, nanotechnology, medicine, tissue engineering, disinfestations and disinfection of books and documents, processes and industrial production and natural resources, among others. The Radiation Technology Centre (RTC) of the Nuclear Energy Research Institute (IPEN), of CNEN, Brazil, developed a small size continuous run and multipurpose industrial - irradiator with a revolutionary design and national technology to be used as a demonstration facility for manufacturers and contract service companies that need economical and logistical in-house irradiation system alternatives. It will be useful for supporting the local scientific community for product and process development using -radiation, assisting the traditional and potential users on process validation, and for training and qualification of operators and radioprotection officers. The technology developed for this facility consists of a continuous tote box transport system comprising a single concrete vault, where the automated transport system of products in and out of the irradiator utilizes a revolving door integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m2 of floor area, the irradiator design is product overlap sources with a maximum 60Co capacity of 37 PBq (tote boxes, Category IV, wet storage). The performed qualification programme of this multipurpose irradiator was based on AAMI/ISO 11137 standard. The irradiator currently holds 7:4 PBq (200 kCi) of 60Co. For irradiator dose optimization, the source distribution was done using the Cadgamma software. The poly-methylmetacrylate (PMMA) dosimeter system was used for irradiator dose mapping. The economic analysis and performance, concerning to the dose uniformity and 60Co utilization efficiency were calculated and compared with other commercial irradiators available in the market. The RTC is involved in establishing a mobile electron beam accelerator unit to treat industrial effluents for reuse purposes. The mobile unit will be equipped with an electron beam accelerator (0:7 MeV, 20 kW) with safety requirements (BSS, IAEA and CNEN Safety Standards), and can be used for effluent treatment from petroleum production, for petroleum desulfurization, and, in addition, for degradation of toxic organic compounds in wastewater for reuse. This project is supported by the IAEA (TC Project BRA1035, 2016–2018) and by the Brazilian Financial of Studies and Project (FINEP). To enlarge the national capacity to treat industrial effluents using electron beam accelerators, the mobile unit treating effluents on site from 1 m3/h up to 1000 m3/day, will provide an effective facility between a laboratory-scale plant to a large-scale plant, with the objective to demonstrate its efficacy and to transfer the technology. Studies have taken place in various productive sectors in the country and in other foreign laboratories to prove that radiation treatment offers technological and economic benefits over conventional techniques for treating recalcitrant pollutants.Capítulo IPEN-doc 22483 Overview of radiation technology for environmental remediation in Brazil2016 - DUARTE, C.L.; BORRELY, S.I.; OIKAWA, H.; MORI, M.N.; RELA, P.R.; COSTA, F.E.; SAMPA, M.H.O.Publicação IPEN-doc 01425 Producao de geradores de sup(99m) Tc com eluicao automatica1982 - MENGATTI, J.; YANAGAWA, S.T.I.; MAZZARRO, E.; GASIGLIA, H.T.; RELA, P.R.; SILVA, C.P.G.; SOSA de PEREIRA, N.P.Artigo IPEN-doc 20962 Characterization of hydrothermal green quartz produced by gamma radiation2015 - ENOKIHARA, CYRO T.; SCHULTZ-GUTTLER, RAINER A.; RELA, PAULO R.