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Super teak is a fast grown species of teak (Tectona grandis Linn. f) derived from several clones. This has facilitated plantation rotations as short as 5 years. The main target of conventional plantation teak was initially for high value logs. Young teak wood from plantation forest usually has a small diameter. Moreover, the wood from very young stems is unsuitable for direct utilization, but advance wood processing technology can improve the wood properties of small diameter logs. This study aimed to assess the potential utilization of young super teak for high quality products namely furniture, flooring, and veneer, and assess the possibility of the use of manufacture waste for pulp paper and wood pellets as side products. The evaluation were carried out according to the National Indonesian Standard and other international standard requirements. 18 logs from wet (Bogor) and dry (Magetan) sites representing large, medium, and small diameter classes were collected. According to SNI 01-0608-1989 Timber for Furniture, 5-year-old super teak was suitable for furniture production. Furthermore, according to SNI 7732.1: 2011: Teak Veneer, the super teak was classified as Grade C because of the presence of sapwood, pinholes, tight and lose knots. According to Australian Timber Flooring Association, 5-year-old super teak was classifiesd as soft flooring group, the same group as mature teak & radiata pine. The young super teak was classified as Class Quality/Group II with very low active alkali consumption and low Kappa Number according to Indonesian wood fibre criteria for pulp and paper materials and Association of Pulp and Paper in Brazil. Finally, based on SNI 802: 2014 Wood Pellet, the super teak was recommended as by-products for utilising the wood waste. [ABSTRACT FROM AUTHOR]

Floods, especially fast floods are very difficult to predict and monitor. Floods can severely affect the life and economy very badly. One of the solutions for flood monitoring can be the usage of wireless sensor network technology for flood monitoring. This bibliometric analysis on this research domain throws light on research trends on WSNs. Most prominent authors, organizations, keywords, and regions were spotted out in this paper. The scope for further research was recommended in this paper. The most influential authors can be Barolli L, Cuka M, Elmazi D, Ikeda M, and Ueyama J. The leaders of research in this domain were India and the United States of America, The most active institute of this research domain was the University of Sao Paulo, in Brazil [ABSTRACT FROM AUTHOR]

In this 21st century, researchers and engineers are using several waste and useless products. These waste materials obtained from agriculture or industries. Rice husk ash, sludge, fly ash and fly ash are waste materials used in concrete mix as supplement of cement. All these waste materials enhanced the mechanical and physical properties of concrete mix. Nowadays Sugarcane bagasse ash is getting the more attention of researcher due its fineness and help to improve the setting properties, strength properties and corrosion retardant. India has sugarcane production about the 341.20 MMT (million metric ton), secured second position in world after the Brazil. Sugarcane peel left as a residue afterthe production of sugar. In this review article, author reviewed several research papers based on uses of bagasse ash in concrete mix. Bagasse ash enhanced the tensile strength, compressive strength, flexural strength the durability and Chloride ion penetration. [ABSTRACT FROM AUTHOR]

Biodiesel is the most promising alternative fuel for replacing diesel in diesel engines, its use as a diesel substitute can reduce emissions of greenhouse gases and smoke. Among the techniques capable of promoting the production of biodiesel, the most used on an industrial scale is the transesterification of raw materials. Brazil has a socioeconomic advantage in the production of biodiesel due to the high availability of raw materials in the agro-industrial sector. A culture capable of providing a low-cost source of triglycerides in the Rio Grande do Sul is the rice culture, as its processing generates bran as a by-product of rice, considered an agricultural residue, from which it is possible to extract vegetable oil. Brazil is the ninth largest rice producer in the world, therefore, the present study aims to explore the production of biodiesel via basic transesterification of rice bran vegetable oil with high quality in order to encourage the use of biofuel and promote the diversification of its matrix. On the whole, the paper leads the conclusion that biodiesel of rice bran oil production via methyl transesterification using KOH as a catalyst with 7.5:1 of molar ratio, 1.25% catalyst and 60 minutes of reaction, is viable and capable of producing biodiesel with the quality required by ANP, EN and ASTM specifications for yield, moisture, kinematic viscosity, acidity index, saponification and iodine. [ABSTRACT FROM AUTHOR]

In this paper, we bring a comparison study between the original genome sequence of SARS-CoV 2 virus, ID: MN908947, coming from China 2019, and sequences of SARS-CoV 2 virus - P.1 variant, coming from Brazil 2021. Using tools of stochastic processes and through the identification of each sequence as being a sample of a stochastic process, after finding the best model for each sequence, we build dendrograms using a metric introduced in [1] that show that the original sequence can be considered in a separated cluster when compared with the P.1 variant. [ABSTRACT FROM AUTHOR]

Fixed-points cells are primary standards in ITS-90. They contain reference material with a purity of 99.999 % or more. The gallium in a melting-point cell, for example, can reach a purity of 99.99999 %. This level of purity is not easy to obtain. However, substances like water and mercury can be purified by means of distillation and chemical procedures. This paper presents the results of mercury triple-point cells made in Brazil that were directly compared to a mercury triple-point cell of 99.999% purity. This reference cell, made by Isotech (England), was previously compared to cells from CENAM (Mexico) and NRC (Canada) and the maximum deviation found was approximately 0.4 mK. The purification stage started with a sample of mercury 99.3 % pure, and the repeated use of both mechanical and chemical processes led to a purification grade considered good enough for calibration of standard platinum resistance thermometers. The purification procedures, the method of construction of the cell, the laboratory facilities, the comparison results and the budget of uncertainties are described in this paper. All of the cells tested have a triple-point temperature within 0.25 mK of the triple-point temperature of the Inmetro reference cell. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper presents a techno-economic analysis to construct an experimental Parabolic Trough Solar collector, using alternative materials and for academic purposes. Concentrated solar power has considerable potential for growth in Brazil, considering the levels of direct solar irradiation, land availability and low current state of use of this technology. It has also a good potential to replace fossil fuels in many thermal applications, helping to decarbonize Brazilian Energy Matrix. The prototype was manually built in a garage. It was made of the following materials: plywood, with steel tube reinforcements for the structure; copper, covered with black ink, for the collector tube; galvanized steel sheets covered with thin aluminum sheets for the reflector. A hydraulic system was developed to run the tests, and an electronic system, using an Arduino-UNO, a laptop and temperature and flow meter sensors to collect data. This prototype does not have neither a solar tracking system nor a glass cover. It has an opening area of 2.34 m2 and had a material cost of around $129.00. Under an estimated direct solar irradiation of 900 W/m2, the prototype was able to absorb heat at a rate of 1.2 kW (52.38% of efficiency). It was also created a simplified method for building similar devices. For the purpose this prototype was built, the materials of the collector tube and the reflector were considered approved. The plywood in the structure had a low reliability and high cost. The results found have limitations for industrial applications, but can offer strategical information for building this type of device in universities and research centers. [ABSTRACT FROM AUTHOR]

In the last decade, the main Brazilian research funding agencies, CNPq and CAPES, have introduced gender projects aimed to understand the situation of women in general and in science in particular. These projects have led to an increased awareness of the problem. There is still a long way to go in the quest for equal access to opportunities and resources. This paper compares the production and quality of work of female scientists with their male colleagues in the physics and astronomy grant-funded research community in Brazil. [ABSTRACT FROM AUTHOR]

Laser propulsion is an innovative concept of accessing the space easier and cheaper where the propulsive energy is beamed to the aerospace vehicle in flight from ground-or even satellite-based high-power laser sources. In order to be realistic about laser propulsion, the Institute for Advanced Studies of the Brazilian Air Force in cooperation with the United States Air Force and the Rensselaer Polytechnic Institute are seriously investigating its basic physics mechanisms and engineering aspects at the Henry T. Hamamatsu Laboratory of Hypersonic and Aerothermodynamics in São José dos Campos, Brazil. This paper describes in details the existing facilities and measuring systems such as high-power laser devices, pulsed-hypersonic wind tunnels and high-speed flow visualization system currently utilized in the laboratory for experimentation on laser propulsion. [ABSTRACT FROM AUTHOR]

Parque Estadual Turístico do Alto Ribeira (PETAR) is located in the South-western part of São Paulo State, in the Ribeira Valley. In this national state park a large number of caves are found, which are among the most visited of the country. These caves, located in a karstic zone, are characterized by the presence of carbonaceous rocks frequently fractured and collapsed. Although, carbonates (dolomites and calcitic rocks) usually have low U content, this element can be found in the structure of the surrounding rocks. This paper aims to determine 238U, 234U, 226Ra and 210Pb concentration in samples of rock, soil, river water and sediment, in Santana cave. The radionuclide 238U was determined by alpha spectrometry using a surface barrier detector. 226Ra and 210Pb were determined by measuring the gross alpha and beta activity on a gas flow proportional counter. [ABSTRACT FROM AUTHOR]

Aiming at increasing awareness of radiation health effects, environmental issues and preventive measures, the Nuclear Energy National Commission (CNEN) launched in 2004 an education and public outreach programme for mine workers, students, teachers, governmental leaders, labor representatives and members of communities nearby small mining sites at the North and Northeast regions. Many Brazilian conventional mines present a significant risk of exposure to radiation due to Uranium and Thorium. CNEN inspects the mines but there are several small mining sites dedicated to open pit short term mineral extraction, called “garimpagem”, that are of difficult control. Therefore, information at large about preventive measures to avoid contamination during exploration, transportation and storage is necessary. CNEN developed an educational campaign which includes a series of open seminars, talks, folders, booklets and posters. The objective of this paper is to present the Brazilian educational campaign to avoid contamination risks at those small mineral exploration sites and its results. This campaign is a joint task that receives collaboration of other organizations such as federal police, schools and universities. [ABSTRACT FROM AUTHOR]

This paper presents the results of a preliminary investigation carried out in a mineral sand processing plant located in the coastal region of Northeastern Brazil. The study aimed to determine the natural radionuclide content of the mineral products extracted from beach sands, with special emphasis on zircon. Measurements were performed through gamma spectrometry, by using a high-purity germanium detector (HPGe) coupled to a multichannel analyzer. Activity concentrations of 226Ra and 228Ra were determined by measuring some of the radon progeny activity concentrations (214Pb and 214Bi for 226Ra, and 228Ac and 208Tl for 228Ra) and assuming an equilibrium condition upstream of the radon progeny. The results of the measurements carried out for the zircon samples showed activity concentrations ranging from 18.09 to 48.51 kBq kg-1 for 226Ra. The results for 228Ra, on the other hand, were consistently lower than those obtained for 226Ra, ranging from 2.72 to 18.31 kBq kg-1. [ABSTRACT FROM AUTHOR]

The Brazilian Synchrotron Light Laboratory has been operating the only light source in the southern hemisphere since July 1997. During this period, approximately 28000 hours of beam time were delivered reaching more than 1000 users per year from all over Brazil as well as from 10 other countries. In this paper, we briefly recall the history of the project and describe the present configuration of the machine and associated instrumentation, focusing on improvements and upgrades of the various light source subsystems and beamlines implemented in recent years. Finally, we report on the use of the facility by the national and international scientific communities, its impact on the scientific and technological scene in Brazil and present perspectives for future improvements of the machine. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The endeavour to adopt and apply the Japanese Lean manufacture concept to the building trade gave rise to lean creation. Continuous improvement, a flattened organisational structure, effective resource utilisation, unused removal, anda cooperative supply chain are all concepts in lean construction. The use of Lean Construction in India is now being disputed, grounded on the achievement of Lean manufacturing and the progress in nations like as Brazil, Denmark, and theUnited States. The study's goal is to identify the obstacles to successful lean structure implementation in the Indian erectionindustry. The information was gathered through a questionnaire review of structure construction project managers and older advisors from architectural and development administration firms. The information gathered was then examined to determine the most significant obstacles, and lean concepts were offered as a way to overcome them. [ABSTRACT FROM AUTHOR]

This study attempts to analyze short-term and long-term time series behavior of volatility by considering the volatility cascade of heterogeneity to generate the stylized facts which have distinctive parameters and attributes that is unavailable in low-frequency data. The information on the stylized facts is significant to improve the accuracy of the volatility forecast based on a different set of volatility model at a different time horizon. The data analysis involved the calculation of daily absolute returns and realized volatility calculated from the 5-min intraday returns of Brazil stock market (BOVESPA) over the period of 2014 - 2020. Both daily and 5-min returns have the kurtosis value lower than 3 which shows that both series are not experienced heavy-tailed. Based on the Box-Pierce Q-Statistics, both series displays the significant result of absence autocorrelations. The result also illustrates that both series features volatility clustering, volatility persistence and leverage effects. The Hurst exponent parameter based on R/S statistics indicates the existence of long-range dependence in high-frequency stock market only. The presence of jumps on the daily and intraday data has been detected by using test for additive jumps in ARMA-GJR (1,1) model and the result shows that more jumps are detected in high-frequency data compared to low-frequency data. All these findings are useful on further research to forecast stock market volatility by using high-frequency data due to the increasing information of stock market at intraday frequencies. The huge availability of high-frequency data has not only contributed to the improvement of previous standard volatility models but has also encouraged further research that not only consider short term period but also a longer horizon volatility forecast. [ABSTRACT FROM AUTHOR]

The Brazilian Amazon is affected by large forest fires resulting from the combination between stronger droughts and human activities. The monitoring of forest fire distribution and its mapping on a large regional scale, especially with remote sensing remains a challenge because the impacts of forest fires are less visible than lands changing and because its spectral signature changes rapidly because of the new growth, until if damages to the forest has outcomes for the structure of forests. We propose a new approach based on the use of the fractional forest cover maps from CLASlite with Landsat data for detected forest fire impacts. The method applied in Paragominas, is a county in the agricultural frontier of the Amazon in Brazil, covering an area of 19,395 km², was impacted by a large fire during the 2015 dryness. The degradation forester by fire had detected by using 2016 Landsat images. A method has been validated with observation points and aerial photo interpretation. The results showed the Non-Photosynthetic Vegetation band increased clearly in the burned area. This variable is useful to map the extent of the burned area. [ABSTRACT FROM AUTHOR]

Archaeometry is an area established in the international community since the 60s, with extensive use of atomic-nuclear methods in the characterization of art, archaeological and cultural heritage objects in general. In Brazil, however, until the early '90s, employing methods of physics, only the area of archaeological dating was implemented. It was only after this period that Brazilian groups became involved in the characterization of archaeological and art objects with these methodologies. The Laboratory of Applied Nuclear Physics, State University of Londrina (LFNA/UEL) introduced, pioneered in 1994, Archaeometry and related issues among its priority lines of research, after a member of LFNA has been involved in 1992 with the possibilities of tomography in archaeometry, as well as the analysis of ancient bronzes by EDXRF. Since then, LFNA has been working with PXRF and Portable Raman in several museums in Brazil, in field studies of cave paintings and in the laboratory with material sent by archaeologists, as well as carrying out collaborative work with new groups that followed in this area. From 2003/2004 LAMFI/DFN/IFUSP and LIN/COPPE/UFRJ began to engage in the area, respectively with methodologies using ion beams and PXRF, then over time incorporating other techniques, followed later by other groups. Due to the growing number of laboratories and institutions/archaeologists/conservators interested in these applications, in may 2012 was created a network of available laboratories, based at http://www.dfn.if.usp.br/lapac. It will be presented a panel of recent developments and applications of these methodologies by national groups, as well as a sampling of what has been done by leading groups abroad. [ABSTRACT FROM AUTHOR]

Women are underrepresented in physics in government research, industry, and academia. In most countries the percentage of women working as professionals in physics has remained at approximately 10%–12% over the last 100 years. This situation has not changed to the present time. A discussion in Physics Today has questioned why the topic is even an issue. This paper will review the current status of women in physics, focusing on developing countries such as Brazil. We present reasons why more women are needed in physics, and propose some strategies to reach that objective. [ABSTRACT FROM AUTHOR]

The Cl and Na concentration values in four types of hyperimmune sera (anti-Bothrops, anti-Diphtheria, anti-Rabies and anti-Tetanus) used for immunological therapy were determined using Neutron Activation Analysis (NAA). These data were compatible with the specifications established by the Word Health Organization (WHO-OMS) and with the Brazilian Official Pharmacopea (Pharmaceutical Code Official of the Country). These data are an important support for quality control of hyperimmune sera production at Butantan Institute (São Paulo city, Brazil), responsible for supplying the Brazilian market. [ABSTRACT FROM AUTHOR]

Current parameterization of radiation in the CPTEC’s (Center for Weather Forecast and Climate Studies, Cachoeira Paulista, SP, Brazil) operational AGCM has its origins in the work of Harshvardhan et al. (1987) and uses the formulation of Ramaswamy and Freidenreich (1992) for the short-wave absorption by water vapor. The UK Met Office’s radiation code (Edwards and Slingo, 1996) was incorporated into CPTEC’s global model, initially for short-wave only, and some impacts of that were shown by Chagas and Barbosa (2006). Current paper presents some impacts of the complete incorporation (both short-wave and long-wave) of UK Met Office’s scheme. Selected results from off-line comparisons with line-by-line benchmark calculations are shown. Impacts on the AGCM’s climate are assessed by comparing output of climate runs of current and modified AGCM with products from GEWEX/SRB (Surface Radiation Budget) project. [ABSTRACT FROM AUTHOR]

Beamed energy propulsion and beamed energy vehicle performance control concepts are equally promising and challenging. In Brazil, the two concepts are being currently investigated at the Prof Henry T Nagamatsu Laboratory of Aerothermodynamics and Hypersonics, of the Institute for Advanced Studies—IEAv, in collaboration with the Rensselaer Polytechnic Institute—RPI, Troy, NY, and the United States Air force Research Laboratory-AFRL. Until recently, only laser energy addition for hypersonic flow control was being investigated at the Laboratory using a 0.3 m nozzle exit diameter hypersonic shock tunnel, T2, and two 7 joule CO2 TEA lasers. Flow visualization, model pressure and heat flux measurements of the laser energy addition perturbed flow around a model were produced as a result of this joint IEAv-RPI investigation. Presently, with the participation of AFRL and the newly commissioned 0.6 m. nozzle exit diameter hypersonic shock tunnel, T3, a more ambitious project is underway. Two 400 Joule Lumonics 620 CO2 TEA lasers will deliver a 20 cm X 25 cm propulsive laser beam to a complete laser propelled air breather/rocket hypersonic engine, located inside T3 test section. Schlieren photographs of the flow inside de engine as well as surface and heat flux measurements will be performed for free stream Mach numbers ranging from 6 to 25. The present paper discusses past, present and future Brazilian activities on beamed energy propulsion and related technologies. [ABSTRACT FROM AUTHOR]

New market requirements have becoming more persistent through the introduction of new technologies that can lead the actual vehicle designs to reach very high safety standards, world class quality levels, reasonable production costs and schedule timing for product development, due new design features and introduction of new materials. To reach those targets, process integration, since the early concept development phases until the start of production, must provide a streamlined scalable environment that encompasses every step in the process from early feasibility to final validation. The experience in supplier process development in the last four years at Volkswagen in Brazil shows that the development of product and processes can be integrated and that the synergy effect of this integration can make it possible to develop mature products and install robust processes to produce them. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Zika virus that became a hot issue in the media recent years behind is very interesting to study, especially the Zika virus has similar to infection to Dengue fever. The virus that is infect to humans through mosquito bites by Aedes genus, Especially Aedes aegypti is identical mosquito that spread Dengue, yellow fever and chikungunya. In Brazil, an increase syndrome Zika virus infection in the community have observed by local health authorities, and also in northeast Brazil an increase of microcephaly condition in babies born. In addition, the Zika virus sporadic infection has reported by approximately 13 Americas countries that show very rapid expansion, and also Indonesia, the euphoria discussed increasingly after the positive patient infected by Zika virus has discovered in Jambi on January 2016. Moving on from this, the authors wanted to know how the sequences protein Zika virus when compared with the Dengue virus, the percentage of identical sequence and also the calculation of local alignment its using the Smith Waterman algorithm. In addition it will also be known genetic mutations that occur in Zika virus from its origin until Zika virus into Indonesia and phylogenetic tree spread of the virus to get to Jambi. So the researcher construct sequence alignment tools by using graphical user interface in MATLAB program based on Smith Waterman algorithm, and also a link in the system with the browser as an option for online data retrieval. From the result of sequence alignment by MATLAB and BLAST, that the identical values of sequence using MATLAB is higher than BLAST values. Likewise, the duration of computation that MATLAB computation is more effective than BLAST computation. [ABSTRACT FROM AUTHOR]

The Amazon River is the world's largest, discharging more water to the ocean than any other river. Study of the world's freshwater resources becomes more significant with increasing awareness of global climate change and its potential effect on those resources and atmospheric forcing. In this work, a reanalysis of the daily discharge and gauge height data for 87 active gauge stations throughout the Amazon River Basin is presented. The data was originally obtained from the web site maintained by ANEEL - Brazilian Electricity Regulatory Agency. We describe the problems encountered in trying to use the original data and the assumptions applied in the reanalysis procedure. The reanalysis consisted of filtering inconsistencies in the comma (decimal) notation, filling in missing data, and replacing inconsistent data values by applying the assumption of a stationary Markov process. The reanalyzed data is available to the community through an anonymous ftp-site. [ABSTRACT FROM AUTHOR]

Biomass burning is a huge source of atmospheric aerosols and is poorly understood leading to large uncertainties in estimates of radiative forcing of climate. Aerosols have both a direct effect on climate by reflecting and absorbing solar radiation and an indirect effect by acting as cloud condensation nuclei (CCN) and ice nuclei (IN). Biomass burning aerosols are produced from burning of vegetation with the vast majority occurring in the tropics. This research presents data collected during the aircraft campaign of the South American Biomass Burning Analysis (SAMBBA) project during September and October 2012. A smouldering rainforest fire and a flaming savannah-like fire were selected for in-depth case studies of the atmospheric plume constituents and provide a comparison between the two fire types. The physiochemical characterization of the two plumes are identified, with preliminary results showing a significant difference in the black carbon concentration of the two plumes; 6μg m-3 for the smouldering rainforest fire and 50μg m-3 for the flaming savannah-like fire. However, organic matter concentrations were similar, peaking at 5mg m-3. Analysis of the gas phase data and calculations of emission ratios (ER) and modified combustion efficiencies (MCE) will be presented together with an analysis of black carbon mixing state using data from a single particle soot photometer and organic aerosol composition. [ABSTRACT FROM AUTHOR]

Land-use changes impact the energy balance of the Earth system, and feedbacks in the Earth system can dampen or amplify this perturbation. We analyze here from satellite data the response of clouds and subsequently radiation to a change of land use for the example of deforestation in the Amazon Basin. In this region, the characteristics of different cloud types over two vegetation types (forest and crop-/grasslands) were calculated for a time period of five years by using satellite data from the instruments MODIS and CERES. The cloud types are defined according to height, optical thickness, and fraction of cloud cover. For calculating the radiative forcing caused by deforestation, the dependency of spatial and temporal averages for the reflected shortwave and outgoing longwave radiation of the top of the atmosphere on vegetation types were determined as well. The results show distinct differences in cloud cover and radiative forcing over crop-/grasslands and forests for the two vegetation regimes, implying a potentially significant positive cloud feedback to deforestation. [ABSTRACT FROM AUTHOR]

The objective of this work was to present a compartmental deterministic mathematical model for representing the dynamics of HLB disease in a citrus orchard, including delay in the disease's incubation phase in the plants, and a delay period on the nymphal stage of Diaphorina citri, the most important HLB insect vector in Brazil. Numerical simulations were performed to assess the possible impacts of human detection efficiency of symptomatic plants, as well as the influence of a long incubation period of HLB in the plant. [ABSTRACT FROM AUTHOR]

The present work investigated Brazilian beach sands in order to analyze the total external natural radiation dose using a gamma-ray spectrometry technique. The activities from the radionuclides 40K and the elements from the series of 238U and 232Th were measured. The sand samples from Morro Branco beach, Ceará, and Itacaré beach, Bahia, presented different colors and grain size than the beaches from São Paulo. A sample collected in Itacaré beach showed an effective dose of 2.5 (1) mSv/yr. This value is outside the annual typical range (0.3-0.6 mSv) indicated by the United Nations Scientific Committee on the Effects of Atomic Radiation. The high effective dose found in Itacaré beach is mainly due to the presence of a large amount of 232Th and 238U. All the other samples collected in Ceará and São Paulo States are inside the annual typical range. Energy-Dispersive X-Ray Spectroscopy (EDS) microanalysis showed that this high external radiation is related to the presence of zircon and monazite, which commonly carry traces of uranium and thorium. [ABSTRACT FROM AUTHOR]

Ground-breaking laser propulsion (LP) experiments were performed under quiescent conditions with a 25 cm wide, two-dimensional Lightcraft model using a Lumonics TEA-622 CO2 laser emitting ∼ 1 μs pulses. In preparation for subsequent hypersonic experiments, this static test campaign was conducted at ambient pressures of 0.06, 0.15, 0.30 and 1 bar with laser pulse energies of 150 to 230 J. Time-variant pressure distributions, generated over engine 'absorption chamber' walls, were integrated to obtain total impulse and momentum coupling coefficients (Cm) representative of a single propulsion cycle. Schlieren visualization of laser-induced air breakdown and expanding blast waves was also accomplished. Surprisingly, the Cm results of 600-3000 Ns/MJ were 2.5x to 5x greater than previous results from smaller Lightcraft models; this suggests that higher static Cm performance can likely be achieved in larger scale LP engines. This research collaboration, forged between the USAF and Brazilian Air Force, was carried out at the Henry T. Nagamatsu Laboratory of Aerothermodynamics and Hypersonics in Brazil. [ABSTRACT FROM AUTHOR]

In this study the potassium levels in blood were determined in male athletes, age 18 to 26 years, before, during and after the tread mill exercise protocol using Neutron Activation Analyses (NAA). These data are important to check the potassium imbalance in blood during the period of competition preparation. [ABSTRACT FROM AUTHOR]

We report a new Accelerator Mass Spectrometry facility at the Physics Institute of Fluminense Federal University in Brazil, the Nuclear Chronology Laboratory—LACRON. The sample preparation laboratory is ready to perform chemical treatment through graphitization and the acquisition of a Single Stage Accelerator Mass Spectrometry System is in progress. LACRON will be the first independent laboratory to perform the 14C-AMS technique not only in Brazil but in Latin America. [ABSTRACT FROM AUTHOR]

The Radioactive Ion Beams Facility (RIBRAS) is in operation since 2004 at the Pelletron Accelerator Laboratory of the University of São Paulo and consists of two superconducting solenoids capable of producing low energy secondary beams of light exotic nuclei. Measurements of the elastic scattering, breakup and transfer reactions with radioactive projectiles such as 6He, 8Li, 7Be on several targets have been performed. A review of the research program carried on along the last four years using the RIBRAS facility is presented. [ABSTRACT FROM AUTHOR]

Radon gas has been monitored in many environments such as rural and urban houses, high natural radioactivity areas and underground mining regions. Nevertheless few data are reported in literature about studies in state buildings. So we get in touch with these buildings managers, where work the Deputy Chamber and the National Congress in Brasília—DF, in order to obtain radon data in these state buildings, so representative for brazilian people. In order to make a preliminary scanning of radon concentration in these buildings, it was put in selected points, radon nuclear track passive detectors type SSNTD, specifically polycarbonate Lexan, which were exposed for periods from two to five months. Afterwards they were sent to Nuclear Engineering Institute in Rio de Janeiro for analysis of 222Rn contents. Derived values, whose average value was about 73 Bq/m3, were all under maximum permissible limits for radon 200 Bq/m3, established by International Comission on Radiological Protection—ICRP 65, for inner environments of houses and state buildings. This work has been coordinated by CNEN Office in Brasélia with effective participation of Nuclear Engineering Institute from CNEN—RJ, that has worked since beginning of april 2004, supplying and analysing radon detectors. [ABSTRACT FROM AUTHOR]

Naturally occurring radioisotopes are present in different concentrations in sedimentary rocks, reflecting the origin of the sediments, the depositional environment, and more recent events such as weathering and erosion. Using a high-resolution γ-ray spectrometry methodology, sedimentary rocks were measured to assess the concentration activities of the natural radioisotopes. The surveyed rocks are from the Irati formation in the Paraná sedimentary basin, which are exposed by an abandoned, open-pit limestone mine, in the city of Sapopema, southern Brazil. The exposed vertical profile is 5 m, and its stratigraphy is represented by an alternation of limestone and bituminous shale (layers being a few decimeters thick), and some millimeter rhythm layers with limestone and bituminous shale laminas. Eleven samples were collected along this profile, each of them dried in the open air during 48 hours, sieved through 4 mm mesh and sealed in cylindrical recipients. Measurements were accomplished using a 66% relative efficiency HPGE detector connected to a standard gamma ray spectrometry electronic chain. The detector efficiency in the range of 60 to 1800 keV was carried out with the certified IAEA-385 sediment sample. The Lower Limit of Detection (LLD) to the system is 2.40 Bq·kg-1 for 226Ra, 1.84 Bq·kg-1 for 232Th and 4.20 Bq·kg-1 for 40K. Activity concentrations were determined for 226Ra (from 16.22 to 151.55 Bq·kg-1), 232Th (from 2.93 to 56.12 Bq·kg-1) and 40K (from 38.45 to 644.63 Bq·kg-1). The layers enriched with organic matter presented the higher values of activity. The measured concentrations of the natural radioisotopes were lower for limestone samples (average values and respective deviations were 22.81±0.22 Bq·kg-1 for 226Ra, 4.21±0.07 Bq·kg-1 for 232Th, and 50.11±0.82 Bq·kg-1 for 40K). Higher concentrations were measured for the bituminous shale samples (average values and respective deviations were 108.10±12.17 Bq·kg-1 for 226Ra, 43.69±0.30 Bq·kg-1 for 232Th, and 465.82±3.99 Bq·kg-1 for 40K). The concentrations were intermediate for the rhythmite samples (average values and respective deviations were 50.69±1.09 Bq·kg-1 for 226Ra, 7.63±0.21 Bq·kg-1 for 232Th, and 85.96±2.47 Bq·kg-1 for 40K). As the analyzed rocks are raw materials for the ceramic, cement and soil correction compound industries, the results of this work furnish data to estimate the contribution of these products to the general public's radiation exposure. [ABSTRACT FROM AUTHOR]

Natural gamma radiation measurements of Quaternary sedimentary deposits were performed with the aim of understanding the provenance and transport processes of sediments along the coastal zone of the Brazilian Southeast. The method employs thorium, uranium and potassium as tracers of the mineralogical properties of beach sand minerals, which reflect the geological history of transport and sorting processes. A considerable positive correlation with the geological evolution of these sandy coastal deposits was observed. [ABSTRACT FROM AUTHOR]

A 14C chronological study from sediments in lacustrine environments in Brazil was developed to assess climate and environmental changes during the Holocene. In the middle of the great debate concerning late glacial in Amazonia, the Holocene period has been somewhat forgotten. The Amazonian climate during Holocene was probably drier and certainly more variable than the present-day one. Global Circulation Models (GCM) applied to 6000 BP pointed out that lower summer insolation was the reason of lower precipitations at that time. [ABSTRACT FROM AUTHOR]

Our Institute of Physics exposes since 1980 didactical exhibitions of holography in Brazil where nice holograms are shown altogether with basic experiments of geometric and wave optics. This experiments lead to the understanding of the phenomenon of images of an ample way. Thousands of people have been present at them, in their majority of the Universidade Estadual de Campinas, where since 2002 they have taken the format of a course without formal evaluation. This way the exhibition has been divided in four modules, in each one of them are shown different holograms, experiments of optics and applications of diffractive images with white light developed in the Institute of Physics. The sequence of the learning through the modules begins with the geometric optics, later we explain the wave optics and finally holography. The phenomenon of the diffraction in daily elements is shown experimentally from the beginning. As well as the application of the holographic screens in white light: the television images that appear in front of the screen and the spectator can try to experience the reality illusion. Put something so exclusive (that only exists in the laboratory) to the public is a way to approximate the persons to an investigation in course. The vision of images that seem to be of holograms, but in movement, and size of until a square meter completes this exhibition of an exclusive way in the world. [ABSTRACT FROM AUTHOR]

In this study the NAA technique was applied to analyze sulfur in blood from inhabitants of Brazil for the proposition of an indicative interval. The measurements were performed considering lifestyle factors (non-smokers, non-drinkers and no history of toxicological exposure) of Brazilian inhabitants. The influence of gender was also investigated considering several age ranges (18-29, 30-39, 40-49, >50 years). These data are useful in clinical investigations, to identify or prevent diseases caused by inadequate sulfur ingestion and for nutritional evaluation of Brazilian population. [ABSTRACT FROM AUTHOR]

We have used gamma-ray spectrometry to study the distribution of natural radiation from soils of southeastern Brazil: Billings reservoir, São Bernardo do Campo Parks, Diadema Parks, Interlagos region, São Paulo, and soil from São Paulo and Rio de Janeiro beaches. In most of the regions studied we have found that the dose due the external exposure to gamma-rays, proceeding from natural terrestrial elements, are between the values 0.3 and 0.6 mSv/year, established by the United Nations Scientific Committee on the Effects of Atomic Radiation. [ABSTRACT FROM AUTHOR]