Does Brazil need new nuclear power plants?

In October 2008, the Brazilian Government announced plans to invest US$212 billion in the construction of nuclear power plants, totaling a joint capacity of 60,000 MW. Apart from this program, officials had already announced the completion of the construction of the nuclear plant Angra III; the construction of large-scale hydroelectric plans in the Amazon and the implantation of natural gas, biomass and coal thermoelectric plants in other regions throughout the country. Each of these projects has its proponents and its opponents, who bring forth concerns and create heated debates in the specialized forums. In this article, some of these concerns are explained, especially under the perspective of the comparative analysis of costs involved. Under such merit figures, the nuclear option, when compared to hydro plants, combined with conventional thermal and biomass-fueled plants, and even wind, to expand Brazilian power-generation capacity, does not appear as a priority.     

巴西实施生物柴油计划的政策举措

巴西联邦政府自“国家乙醇燃料计划”的大胆创新和有益尝试以来，已经探索出了很多宝贵经验，并于2004年年底正式启动“生物柴油计划”。在该计划的实施中，政策引导、法律监管、税收优惠、金融扶持等各种手段的组合应用使得该计划在启动不到4年的时间里，就已经开始逐渐显现成果。估计至2008年底，巴西生物柴油年产量约为35×10^8L，B5柴油的实施极有可能提前实现。同时，该计划增加了贫困地区的收入，并为社会提供了将近21万个就业机会。无论从国家安全战略，还是从可持续发展的角度而言，巴西在发展生物燃料方面的举措对于同样是发展中国家的我国来说，是值得借鉴的。     

Field Observations of Ipanema Beach Outfall

Field observations of the Ipanema Beach, Rio de Janeiro, Brazil, ocean sewage outfall were obtained by adding dye tracers to the effluent and simultaneously measuring oceanographic conditions. Four experiments were performed, two during unstratified conditions, and two during stratified conditions. When stratified, the plume was trapped below the thermocline with low dilution, around 35 to 1, when unstratified, the plume surfaced and the dilution increased to more than 100 to 1. The results were compared with predictions of some commonly used near field plume mathematical models: UM3, RSB, and CORMIX. With suitable assumptions, all the models reasonably predict near field dilution. RSB predicts near field results directly; for UM3 and CORMIX, it was assumed that the end of the near field occurs when the plume reaches its terminal rise height or impacts the free surface. Different assumptions about the shape of the density profiles in CORMIX resulted in widely differing predictions of dilution. While the gross properties of the plume can be reasonably predicted by plume models, there remain many aspects which cannot be, particularly the patchy nature of the wastefield that has been observed here and in other field tests.     

基于互信息量的CMMB系统物理层抽象算法

为了准确和高效地评估在构建下一代广播电视网（NGB）中起重要作用的中国移动多媒体广播（CMMB）系统的链路传输性能,根据CMMB协议标准,利用大量高斯信道下的仿真数据拟合出了接收比特互信息率（RBIR）与误帧率(FER)之间的一一对应关系,然后给出了基于互信息量的CMMB物理层抽象算法——能在解调的输入端计算平均互信息量的RBIR算法,并利用开发的CMMB物理链路仿真平台在巴西信道模型中验证了该抽象算法的准确性：能够精确地预测当前无线信道的质量。     

Maringá: A British Garden City in the tropics

Maringá, located in southern Brazil, deserves to be studied because of its uniqueness. It is one of a few cities designed according to Garden City principles and developed by the British in Brazil as part of a regional network of cities connected by rail. The city also distinguishes itself from several other cities in Brazil because it is the seat of a metropolitan region that, despite having had the highest growth of all metropolitan regions in the state of Paraná in the 1990s, has managed to prevent informal settlements from developing within its boundaries. This profile describes the creation and growth of this young, mid-sized city, the design principles followed by its founders, and the political and socioeconomic reasons for its successful development. A critical evaluation of regional planning efforts and shortcomings of a Garden City-inspired design raises issues and describes challenges to be faced by Maringá in the near future. The article concludes that Maringá’s responses to these challenges will determine what kind of future the city will have. Ultimately, a concerted effort to keep its exceptional characteristics will need to be made if its citizens are to maintain the quality of life they have enjoyed during the first half-century of its existence.     

含预制裂隙的均质岩石巴西劈裂过程数值模拟

基于改进刚体弹簧方法,对均质圆盘试件和预制裂隙圆盘试件的巴西劈裂过程进行了数值模拟,并对比研究了预制裂隙对巴西劈裂破坏形态的影响。结果表明,均质圆盘的巴西劈裂过程分为三个阶段,即加载端开始向下萌生随机裂隙点;裂隙点之间联结发育;主裂隙贯穿试件造成破坏,次生裂隙发育。对于预制裂隙圆盘试件,不同预制裂隙倾角试件的破坏形式基本一致,由于应力集中,裂纹首先从预制裂隙两端萌生,并向加载端扩展,宏观裂纹形成的同时在加载端部也开始产生次生裂隙,次生裂纹的产状随预制裂隙倾角变化而不同。     

Critical points of Brazil nuts: a beginning for food safety,quality control and Amazon sustainability

BACKGROUND: One difficulty of self‐sustainability is the quality assurance of native products. This research was designed to study the risks and critical control points in the collection, handling and marketing of Brazil nuts from native forests and urban fairs in the Brazilian Amazon by characterisation of morphological aspects of fungi and posterior identification by molecular biology and determination of aflatoxins by high‐performance liquid chromatography. RESULTS: Several corrective actions to improve product quality were found to be necessary in both sites. Growth of fungi was observed in 95% of fragments of Brazil nuts from both sites during the between‐harvest period. Aflatoxin levels indicated that, although fungal growth was observed in both sites, only Brazil nuts from the native forest showed a high risk to human health (total aflatoxin level of 471.69 µg kg^?1). CONCLUSION: This study has shown the main issues related to the process design of Brazil nuts, supporting the necessity for research on new strategies to improve the quality of nuts. Also, the habit of eating Brazil nuts stored throughout the year may represent a risk to farmers. © 2012 Society of Chemical Industry     

巴西甘蔗品种在广西的种性表现及利用前景

先后从巴西引进了一批具有生物固氮能力,低耗氮肥的甘蔗品种.2003～2004年选择其中6个固氮甘蔗品种,以桂糖11号（CK1）和ROC16（CK2）为对照种进行品比种性试验,1年新植1年宿根结果表明：RB86/7515、RB72/454、RB92/8064表现中熟、高糖、丰产、宿根性强,公顷产蔗量比CK2增22.6%～29.3%,比CK1增16.4%～22.8%,公顷含糖量比CK2增20.3%～22.4%,比CK1增15.9%～17.9%,这3个品种可作为中熟品种在广西蔗区繁殖推广,也可作为高产及强宿根亲本杂交利用.其余参试品种的综合表现不及CK1、CK2,其中SP80/1842可作为高糖种质利用,NA5679、RB83/5089可作为固氮种质保存.本文对RB86/7515、RB72/454、RB92/8064等品种的形态特征,农艺特性进行描述.     

Aflatoxin production by Aspergillus flavus in Brazil nuts

Experiments were conducted to evaluate the effects of relative humidity (r.h.; 75%, 80%, 85%, 97%) and temperature (10, 13, 15, 25, 30 °C) on aflatoxin production in previously dried (3.5% moisture content; m.c.) Brazil nuts. Initially Aspergillus spp. were isolated from the surfaces of whole in-shell (WIS) Brazil nuts imported from Peru using A. flavus and A. parasiticus agar (AFPA). Isolates were subsequently screened for aflatoxin production using yeast extract sucrose medium. Total aflatoxin (B₁+B₂+G₁+G₂+M₁) was analyzed using an immunoassay technique while the presence of aflatoxin was confirmed using thin-layer chromatography. The surface of shelled half-nuts (simulating damaged or trimmed nuts), shelled whole (SW) nuts, and WIS nuts following a chlorine wash and water rinse, served as sites for inoculation (10 μl; 10⁵/ml) using an aflatoxigenic isolate. Maximum concentrations of total aflatoxin and B₁ were detected in nuts stored at 97% r.h. and at temperatures of 25–30 °C. Shelled half-nuts contained the highest total (6817 ng/g) and B₁ (4483 ng/g) aflatoxin. WIS nuts contained the least total and B₁ toxin with maximum concentrations of 93 and 49 ng/g, respectively. Aflatoxin was not detected (detection limit of 1.75 ng/g) in nuts maintained at either 10 °C (97% r.h.) or at 30 °C (75% r.h.) for up to 60 d. Maximal moisture contents (%) and water activity values (a_W) for nuts stored at these conditions were 4.50 and 0.78, and 9.14 and 0.92, respectively. Results of this study indicate that the limiting moisture content and a_W values required to control aflatoxin production () in SW and WIS stored at 30 °C for up to 60 d are 4.5, 0.68, 5.0, and 0.75, respectively. Overall, increasing the relative humidity and temperature during storage resulted in an increase in aflatoxin and these were shown to be the most significant variables influencing toxin production in Brazil nuts.