Collecção das Leis do Imperio do Brazil de 1889

Parte 1 - Atos do Poder Legislativo

Interface Fracture Behavior Of Electroplated Coating On Metal Substrate Under Compressive Strain

The inducement of interface fracture is crucial to the analysis of interfacial adhesion between coating and substrate. For electroplated coating/metal substrate adhering materials with strong adhesion, interface cracking and coating spalling are difficult to be induced by conventional methods. In this paper an improved bending test named as T-bend test was conducted on a model coating system, i.e. electroplated chromium on a steel substrate. After the test, cross-sections of the coated materials were prepared to compare the failure behaviors under tensile strain and compressive strain induced by T-bend test. And the observation results show that coating cracking, interface cracking and partial spalling appear step by step. Based on experimental results, a new method may be proposed to rank the coated materials with strong inter-facial adhesion. (C) 2008 Elsevier B.V. All rights reserved.

基于广义模型和分类回归树的中国常见树种地理分布模拟研究

研究植被、物种分布与环境的关系一直是生态学中的重点。长期以来，在全球变化与陆地生态系统的研究中，主要研究重点是对大尺度植被分布的模拟和预测，并建立了大量的气候－植被分布关系模型。而对于物种潜在分布的模拟和预测，国内外相关的研究较少。近年来，随着统计技术和地理信息系统的发展，用于预测物种分布的统计模型技术得到了迅速的发展。统计模型技术已被广泛应用于生物地理分布、植物群落、生物多样性、气候变化影响评估等方面。 本论文基于当前在物种分布研究中应用广泛的广义线性模型、广义加法模型及分类回归树3种统计模型技术，对我国常见树种的地理分布进行模拟分析，并比较不同模型模拟精度的优劣，将模拟精度较高的模型应用于预测未来气候情景下我国几种主要树种的未来潜在地理分布。 基于建立的广义线性模型（GLM）、二次项逐步回归广义线性模型（SGLM）、广义加法模型（GAM）和分类回归树（CART）4个模型对我国20种常见树种地理分布进行模拟，结果表明，4个模型均有较高的模拟精度。GAM的模拟精度最高;添加二次项并进行逐步回归有效的提高了GLM的模拟精度;CART是一种基于规则的模型技术，模拟结果比GLM稍好，比GAM略差。 对不同树种的模拟分析表明，4个模型对于主要分布在暖温带落叶阔叶林区域的油松、辽东栎分布的模拟结果较差;GLM对分布在温带针阔混交林中红松、蒙古栎、胡桃楸和糠椴的模拟结果不太理想;4个模型对分布在中国亚热带常绿阔叶林区域的树种均表现出较高的模拟精度;对广布种也表现出很高的模拟精度。 结合地理信息系统，以地图形式将青冈、油松的模拟结果表示出来。结果表明：地理信息系统直观的反映出了模型模拟结果差异。4个模型均能很好模拟青冈的分布，且模拟结果接近;而对油松分布模拟结果4个模型均不甚理想，以GLM最差。这些结果与模型模拟评估结果相吻合。 在未来气候变化情景下，基于4个模型模拟结果优劣，以我国三种主要造林树种马尾松、油松、红松和两种常见树种青冈、蒙古栎为研究对象，分析其未来变化趋势。结果表明，未来气候变化情景下，对于马尾松而言，4个模型均预测马尾松在基本保持原有分布的基础上，其未来潜在分布区域均有所扩大，且有向西和向北扩展的趋势;对于油松而言，基于GLM、SGLM和GAM3个模型，油松的未来潜在分布除有北移的趋势外，其分布区还将向东北和西南两个方向扩展;对于红松而言，基于SGLM、GAM和CART3个模型的预测结果较为接近，即红松的未来潜在分布区域将有所减少;对蒙古栎而言，4个模型预测蒙古栎未来分布均将向西扩展;对青冈而言，4个模型预测青冈能基本保持其原有分布区，并向西和向北扩展，其中CART预测结果还表明，青冈在广东南部及广西南部的分布区域将消失。

Habitat degradation and conservation status assessment of gallinaceous birds in the Trans-Himalayas, China

The greatest concentration of Chinese Galliformes occurs in the Trans-Himalayas. We selected 4 northwestern Yunnan counties (Lijiang, Shangri-la, Deqin, and Weixi) in the Trans-Himalayas to assess the conservation status of 9 gallinaceous forest birds. We

Performance prediction of graphene nanoribbon and carbon nanotube transistors

Carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) field-effect transistor (FET) can be the basis for a quasi-one- dimensional (Q1D) transistor technology. Recent experiments show that the on-off ratio for GNR devices can be improved to level exploration of transistor action is justified. Here we use the tight-binding energy dipersion approximation, to assess the performance of semiconducting CNT and GNR is qualitatively in terms of drain current drive strength, bandgap and density of states for a specified device. By reducing the maximum conductance 4e2/h by half, we observed that our model has a particularly good fit with 50 nm channel single walled carbon nanotube (SWCNT) experimental data. Given the same bandgap, CNTs outperform GNRs due to valley degeneracy. Nevertheless, the variation of the device contacts will decide which transistor will exhibit better conductivity and thus higher ON currents. © 2011 American Institute of Physics.

MEIOTIC CHROMOSOME BEHAVIOR IN FEMALE INTERSEXES OF ARTIFICIAL TRIPLOID TRANSPARENT-COLORED CRUCIAN CARP

Chromosome behavior in meiosis was studied by air-drying, C-banding and surface-spreading methods in female intersexes of artificial triploid transparent-colored crucian carp (Carassius auratus). Chromosome pairing and contraction were obviously asynchronous. The preferential pairing of two homologous chromosomes was the major pattern of chromosome pairing, and a few triple pairing, repeated pairing, telomer or centromere associating and multiple pairing were also observed in the pachytene cells. The metaphase I cells were mainly composed of univalents, bivalents and trivalents, as well as few of other multivalents, such as tetravalents, pentavalents, hexavalents and heptavalents, were also found in some metaphase I cells. The chromosome elements including uni-, bi-, tri- and other multivalents varied considerably among the metaphase I cells, and the associating patterns of multivalents were also diverse. Some 6 n and 12 n cells, in which premeiotic endomitosis occurred once or twice, were found at the prophase and first metaphase of meiosis, and the pairing and associating patterns were basically similar to that of the triploid cells.

Adaptive fading Kalman filter with an application

A new adaptive state estimation algorithm, namely adaptive fading Kalman filter (AFKF), is proposed to solve the divergence problem of Kalman filter. A criterion function is constructed to measure the optimality of Kalman filter. The forgetting factor in AFKF is adaptively adjusted by minimizing the defined criterion function using measured outputs. The algorithm remains convergent and tends to be optimal in the presence of model errors. It has been successfully applied to the headbox of a paper-making machine for state estimation.