PICES Press, Vol. 9, No. 2, July 2001

Cover [pdf, 0.2 Mb] Climate, biodiversity and ecosystems of the North Pacific [pp. 1-2] [pdf, 0.2 Mb] The state of the western North Pacific in the second half of 2000 [pp. 3-5] [pdf, 0.8 Mb] The status of the Bering Sea: June – December 2000 [pp. 6-7] [pdf, 1.5 Mb] The state of the eastern North Pacific since autumn 2000 [p. 8] [pdf, 0.3 Mb] Korean Yellow Sea Large Marine Ecosystem Program [pp. 9-12] [pdf, 0.5 Mb] Past and ongoing Mexican ecosystem research in the northeast Pacific Ocean [pp. 13-15] [pdf, 0.3 Mb] Vera Alexander [pp. 16-19] [pdf, 1.0 Mb] North Pacific CO2 data for the new millennium [pp. 20-21] [pdf, 0.3 Mb] PICES Higher Trophic Level Modelling Workshop [pp. 22-23] [pdf, 0.4 Mb] Argo Science Team 3rd Meeting (AST-3) [pp. 24-25] [pdf, 0.3 Mb] 2001 coast ocean / salmon ecosystem event [p. 26-27] [pdf, 0.3 Mb] Shifts in zooplankton abundance and species composition off central Oregon and southwestern British Columbia [pp. 28-29] [pdf, 0.3 Mb] The CLIVAR - Pacific Workshop [p. 30] [pdf, 0.2 Mb] PICES dialogue with Mexican scientists [p. 31] [pdf, 0.2 Mb] Announcements [p. 32] [pdf, 0.2 Mb]

Relatório apresentado a S. Ex. o Sr. Ministro da Industria, Viação e Obras Públicas =Rapport présenté a Son Ex. M. le Ministre de l'Industrie, de la Voirie et des Travaux Publics /por L. Cruls. --Relatório da Comissão Exploradora do Planalto Central do Brazil = Rapport de la Commission d'Exploration du Plateau Central du Brésil

Documento com duas páginas-de-rosto, em português e francês. Título em francês : Rapport présenté a Son Ex. M. le Ministre de l'Industrie, de la Voirie et des Travaux Publics

Relatório apresentado a S. Ex. o Sr. Ministro da Industria, Viação e Obras Públicas = Rapport présenté a Son Ex. M. le Ministre de l'Industrie, de la Voirie et des Travaux Publics por L. Cruls

Trata-se do "Relatório Cruls", referente à 1ª Missão Cruls (1892-1893), durante o governo Floriano Peixoto

微/纳米力学测试技术及其应用

<p>pace="6" width="100" height="139" align="left" />&nbsp;&nbsp;&nbsp; 本书系统地介绍了微／纳米力学测试技术中最常用的压入和划入技术及其典型应用。全书共分13章。测试技术方面，内容涉及接触力学、测试原理、方法、校准、仪器、力学参量、影响因素。典型应用方面，内容涉及在表面工程、微机电系统、生物、高聚物和金属玻璃等领域内的微／纳米力学行为的测试。本书可供力学、材料、物理、电子、机械、生物和化学等领域的研究人员、工程技术人员以及大专院校相关专业的师生参考。p><p>目录p><p>前言p><p>第1章 绪论p><p>1.1硬度的定义和分类p><p>1.2纳米压入和划入技术的发展p><p>1.3纳米压入和划入技术的特点p><p>参考文献p><p>第2章 压入接触力学p><p>2.1弹性接触p><p>2.1.1 Soeddon解p><p>2.1.2锥形压针p><p>2.1.3球形压针p><p>2.1.4圆柱压针p><p>2.2弹塑性接触p><p>2.2.1塑性发生p><p>2.2.2完全塑性p><p>2.2.3材料响应p><p>参考文献p><p>第3章 纳米压入测试原理p><p>3.1压入硬度和模量p><p>3.2连续刚度测量p><p>3.3载荷一深度数据确定的材料参数p><p>3.3.1马氏硬度p><p>3.3.2压入蠕变p><p>3.3.3压入松弛p><p>3.3.4压入弹性功和塑性功p><p>参考文献p><p>第4章 纳米压入测试方法p><p>4.1压针类型p><p>4.1.1玻氏压针p><p>4.1.2立方角压针p><p>4.1.3维氏压针p><p>4.1.4努氏压针p><p>4.1.5圆锥压针p><p>4.1.6球形压针p><p>4.1.7圆柱压针p><p>4.1.8楔形压针p><p>4.1.9考虑因素p><p>4.2测试环节p><p>4.2.1样品准备p><p>4.2.2环境控制p><p>4.2.3间距选择p><p>4.2.4表面探测p><p>4.2.5驱动方式p><p>4.2.6测试步骤p><p>4.2.7测试报告p><p>参考文献p><p>第5章 纳米压入的确认和校准p><p>5.1直接确认和校准p><p>5.2间接校准p><p>5.3测试和校准的实例p><p>参考文献p><p>第6章 纳米压入和划入的测量仪器p><p>6.1仪器技术指标的定义p><p>6.2美国Mrs公司p><p>6.3美国Hysitmn公司p><p>6.4瑞士CSM公司p><p>6.5英国MML公司p><p>6.6澳大利亚CSIRO公司p><p>6.7测量仪器的发展趋势p><p>参考文献p><p>第7章 力学参量的测量p><p>7.1压入方式p><p>7.1.1硬度和模量p><p>7.1.2断裂韧度p><p>7.1.3蠕变和粘弹行为p><p>7.1.4压入应力??应变曲线p><p>7.1.5加卸载曲线涉及的p><p>部分现象p><p>7.2划人方式p><p>7.2.1块体材料p><p>7.2.2薄膜材料p><p>7.2.3粗糙度p><p>7.3弯曲方式p><p>7.3.1微悬臂梁静载弯曲p><p>7.3.2微桥静载弯曲p><p>7.3.3微结构疲劳p><p>7.4吸引方式p><p>7.5声发射测试p><p>7.6温度测试p><p>参考文献.p><p>第8章 影响纳米压入测试的因素p><p>8.1测试仪器的影响p><p>8.1.1压针缺陷p><p>8.1.2测试方法p><p>8.1.3接触零点的确定p><p>8.1.4载荷和位移的分辨力p><p>8.2样品的表面状态和性质p><p>8.2.1表面吸湿p><p>8.2.2表面粗糙度p><p>8.2.3残余应力p><p>8.2.4凹陷和凸起变形p><p>8.3纳米压入和划入测试所面临的问题p><p>参考文献p><p>第9章 在表面工程中的应用p><p>9.1金属材料表面激光强化的力学表征p><p>9.2硬质膜的力学和摩擦学性能评估p><p>9.2.1显微硬度测试p><p>9.2.2纳米压人测试p><p>9.2.3纳米划入测试p><p>9.2.4膜材的影响p><p>参考文献p><p>第10章 在微机电系统中的应用p><p>10.1薄膜测试p><p>10.1.1典型薄膜材料的硬度和模量p><p>10.1.2薄膜疲劳p><p>10.1.3淀积工艺对二氧化硅薄膜力学性质的影响p><p>10.2微结构弯曲p><p>10.2.1微结构的静态弯曲p><p>10.2.2微结构的动态弯曲p><p>参考文献p><p>第11章 在生物及其相关材料中的应用p><p>11.1人工林杉木管胞细胞壁p><p>11.2人体腰椎骨p><p>11.3存储液对人体牙齿微力学性能的影响p><p>参考文献p><p>第12章 在高聚物中的应用p><p>12.1PMMA单轴拉伸和弯曲力学行为p><p>12.2划入测试的理论分析p><p>12.3韧性行为的描述p><p>12.4脆性行为的描述p><p>12.4.1温度效应p><p>12.4.2应变率效应p><p>参考文献p><p>第13章 在金属玻璃中的应用p><p>13.1硬度和屈服应力的关系p><p>13.2不连续的塑性变形p><p>13.3压痕形貌和微结构变化p><p>13.4应变率效应p><p>13.5钕基金属玻璃的变形行为p><p>参考文献p><p>附录 常见问题的回答p><p>1测试数量p><p>2压入间距p><p>3压入深度p><p>4泊松比的选择p><p>5典型材料的参数p><p>6断裂韧度测试压针的选择p><p>7纳米薄膜的测试p><p>8典型材料的压入变形行为p><p>9显微硬度和纳米压入硬度的关系p><p>10压入影响区及其边界效应p><p>10.1压入影响区的有限元模拟p><p>10.2边界距离影响的有限元模拟p><p>10.3压人间距影响的测试p><p>参考文献p>

Galeria dos brasileiros illustres (os contemporaneos) : retratos dos homens mais illustres do Brasil na politica, sciencias e letras, desde a guerra da independencia até os nossos dias : copiados do natural e lithographados por S.A. Sisson, acompanhados das suas respectivas biographias, publicada sob a protecção de sua Magestade o Imperador

Galeria dos brasileiros illustres traz retratos copiados do natural e litografados das principais figuras brasileiras da política, ciências e letras, com biografias redigidas por diversos escritos da época, por alguns dos próprios biografados ou por membros de suas famílias. Considerada a mais importante de Sisson, esta obra teve tiragem reduzida e muitos exemplares foram desmanchados por antiquários que emolduravam os retratos, vendendo-os por alto preço. Segundo Borba de Moraes, "é muito difícil encontrar-se hoje em dia um exemplar perfeito e em boas condições" e que "só muito raramente aparece um exemplar à venda."

Reflexões sobre a metaphysica do calculo infinitesimal

Referência: Diccionario Bibliographico Portuguez / Innocencio Francisco da Silva, 1884 v. 6, p. 8

Exposição, e confrontação das cartas de lei de 15 de novembro de 1825

Referência : Diccionario Bibliographico Portuguez / Innocencio Francisco da Silva, 1859. v. 2, 254 p.

I. Rigid body penetration into brittle materials. II. Phase change effect on shock wave propagation

<p>Part I.p> <p>We have developed a technique for measuring the depth time history of rigid body penetration into brittle materials (hard rocks and concretes) under a deceleration of ~ 10p>5p> g. The technique includes bar-coded projectile, sabot-projectile separation, detection and recording systems. Because the technique can give very dense data on penetration depth time history, penetration velocity can be deduced. Error analysis shows that the technique has a small intrinsic error of ~ 3-4 % in time during penetration, and 0.3 to 0.7 mm in penetration depth. A series of 4140 steel projectile penetration into G-mixture mortar targets have been conducted using the Caltech 40 mm gas/ powder gun in the velocity range of 100 to 500 m/s.p> <p>We report, for the first time, the whole depth-time history of rigid body penetration into brittle materials (the G-mixture mortar) under 10p>5p> g deceleration. Based on the experimental results, including penetration depth time history, damage of recovered target and projectile materials and theoretical analysis, we find:p> <p>1. Target materials are damaged via compacting in the region in front of a projectile and via brittle radial and lateral crack propagation in the region surrounding the penetration path. The results suggest that expected cracks in front of penetrators may be stopped by a comminuted region that is induced by wave propagation. Aggregate erosion on the projectile lateral surface is < 20% of the final penetration depth. This result suggests that the effect of lateral friction on the penetration process can be ignored.p> <p>2. Final penetration depth, P_max, is linearly scaled with initial projectile energy per unit cross-section area, e_s , when targets are intact after impact. Based on the experimental data on the mortar targets, the relation is P_max(mm) 1.15e_s (J/mmp>2p> ) + 16.39.p> <p>3. Estimation of the energy needed to create an unit penetration volume suggests that the average pressure acting on the target material during penetration is ~ 10 to 20 times higher than the unconfined strength of target materials under quasi-static loading, and 3 to 4 times higher than the possible highest pressure due to friction and material strength and its rate dependence. In addition, the experimental data show that the interaction between cracks and the target free surface significantly affects the penetration process.p> <p>4. Based on the fact that the penetration duration, t_max, increases slowly with e_s and does not depend on projectile radius approximately, the dependence of t_max on projectile length is suggested to be described by t_max(μs) = 2.08e_s (J/mmp>2p> + 349.0 x m/(πRp>2p>), in which m is the projectile mass in grams and R is the projectile radius in mm. The prediction from this relation is in reasonable agreement with the experimental data for different projectile lengths.p> <p>5. Deduced penetration velocity time histories suggest that whole penetration history is divided into three stages: (1) An initial stage in which the projectile velocity change is small due to very small contact area between the projectile and target materials; (2) A steady penetration stage in which projectile velocity continues to decrease smoothly; (3) A penetration stop stage in which projectile deceleration jumps up when velocities are close to a critical value of ~ 35 m/s.p> <p>6. Deduced averaged deceleration, a, in the steady penetration stage for projectiles with same dimensions is found to be a(g) = 192.4v + 1.89 x 10p>4p>, where v is initial projectile velocity in m/s. The average pressure acting on target materials during penetration is estimated to be very comparable to shock wave pressure.p> <p>7. A similarity of penetration process is found to be described by a relation between normalized penetration depth, P/P_max, and normalized penetration time, t/t_max, as P/P_max = f(t/t_max, where f is a function of t/t_max. After f(t/t_max is determined using experimental data for projectiles with 150 mm length, the penetration depth time history for projectiles with 100 mm length predicted by this relation is in good agreement with experimental data. This similarity also predicts that average deceleration increases with decreasing projectile length, that is verified by the experimental data.p> <p>8. Based on the penetration process analysis and the present data, a first principle model for rigid body penetration is suggested. The model incorporates the models for contact area between projectile and target materials, friction coefficient, penetration stop criterion, and normal stress on the projectile surface. The most important assumptions used in the model are: (1) The penetration process can be treated as a series of impact events, therefore, pressure normal to projectile surface is estimated using the Hugoniot relation of target material; (2) The necessary condition for penetration is that the pressure acting on target materials is not lower than the Hugoniot elastic limit; (3) The friction force on projectile lateral surface can be ignored due to cavitation during penetration. All the parameters involved in the model are determined based on independent experimental data. The penetration depth time histories predicted from the model are in good agreement with the experimental data.p> <p>9. Based on planar impact and previous quasi-static experimental data, the strain rate dependence of the mortar compressive strength is described by σ_f/σp>0p>_f = exp(0.0905(log(έ/έ_0) p>1.14p>, in the strain rate range of 10p>-7p>/s to 10p>3p>/s (σp>0p>_f and έ are reference compressive strength and strain rate, respectively). The non-dispersive Hugoniot elastic wave in the G-mixture has an amplitude of ~ 0.14 GPa and a velocity of ~ 4.3 km/s.p> <p>Part II. p> <p>Stress wave profiles in vitreous GeO₂ were measured using piezoresistance gauges in the pressure range of 5 to 18 GPa under planar plate and spherical projectile impact. Experimental data show that the response of vitreous GeO₂ to planar shock loading can be divided into three stages: (1) A ramp elastic precursor has peak amplitude of 4 GPa and peak particle velocity of 333 m/s. Wave velocity decreases from initial longitudinal elastic wave velocity of 3.5 km/s to 2.9 km/s at 4 GPa; (2) A ramp wave with amplitude of 2.11 GPa follows the precursor when peak loading pressure is 8.4 GPa. Wave velocity drops to the value below bulk wave velocity in this stage; (3) A shock wave achieving final shock state forms when peak pressure is > 6 GPa. The Hugoniot relation is D = 0.917 + 1.711u (km/s) using present data and the data of Jackson and Ahrens [1979] when shock wave pressure is between 6 and 40 GPa for ρ₀ = 3.655 gj cmp>3p> . Based on the present data, the phase change from 4-fold to 6-fold coordination of Gep>+4p> with Op>-2p> in vitreous GeO₂ occurs in the pressure range of 4 to 15 ± 1 GPa under planar shock loading. Comparison of the shock loading data for fused SiO₂ to that on vitreous GeO₂ demonstrates that transformation to the rutile structure in both media are similar. The Hugoniots of vitreous GeO₂ and fused SiO₂ are found to coincide approximately if pressure in fused SiO₂ is scaled by the ratio of fused SiO₂to vitreous GeO₂ density. This result, as well as the same structure, provides the basis for considering vitreous Ge0₂ as an analogous material to fused SiO₂ under shock loading. Experimental results from the spherical projectile impact demonstrate: (1) The supported elastic shock in fused SiO₂ decays less rapidly than a linear elastic wave when elastic wave stress amplitude is higher than 4 GPa. The supported elastic shock in vitreous GeO₂ decays faster than a linear elastic wave; (2) In vitreous GeO₂ , unsupported shock waves decays with peak pressure in the phase transition range (4-15 GPa) with propagation distance, x, as α 1/xp>-3.35p> , close to the prediction of Chen et al. [1998]. Based on a simple analysis on spherical wave propagation, we find that the different decay rates of a spherical elastic wave in fused SiO₂ and vitreous GeO₂ is predictable on the base of the compressibility variation with stress under one-dimensional strain condition in the two materials.p>

Magnetohydrodynamic turbulence

<p>We simulate incompressible, MHD turbulence using a pseudo-spectral code. Our major conclusions are as follows.p> <p>1) MHD turbulence is most conveniently described in terms of counter propagating shear Alfvén and slow waves. Shear Alfvén waves control the cascade dynamics. Slow waves play a passive role and adopt the spectrum set by the shear Alfvén waves. Cascades composed entirely of shear Alfvén waves do not generate a significant measure of slow waves.p> <p>2) MHD turbulence is anisotropic with energy cascading more rapidly along k_⊥ than along k_∥, where k_⊥ and k_∥ refer to wavevector components perpendicular and parallel to the local magnetic field. Anisotropy increases with increasing k_⊥ such that excited modes are confined inside a cone bounded by k_∥ ∝ kp>γp>_⊥ where γ less than 1. The opening angle of the cone, θ(k_⊥) ∝ kp>-(1-γ)p>_⊥, defines the scale dependent anisotropy.p> <p>3) MHD turbulence is generically strong in the sense that the waves which comprise it suffer order unity distortions on timescales comparable to their periods. Nevertheless, turbulent fluctuations are small deep inside the inertial range. Their energy density is less than that of the background field by a factor θp>2p> (k_⊥)≪1.p> <p>4) MHD cascades are best understood geometrically. Wave packets suffer distortions as they move along magnetic field lines perturbed by counter propagating waves. Field lines perturbed by unidirectional waves map planes perpendicular to the local field into each other. Shear Alfvén waves are responsible for the mapping's shear and slow waves for its dilatation. The amplitude of the former exceeds that of the latter by 1/θ(k_⊥) which accounts for dominance of the shear Alfvén waves in controlling the cascade dynamics.p> <p>5) Passive scalars mixed by MHD turbulence adopt the same power spectrum as the velocity and magnetic field perturbations.p> <p>6) Decaying MHD turbulence is unstable to an increase of the imbalance between the flux of waves propagating in opposite directions along the magnetic field. Forced MHD turbulence displays order unity fluctuations with respect to the balanced state if excited at low k by δ(t) correlated forcing. It appears to be statistically stable to the unlimited growth of imbalance.p> <p>7) Gradients of the dynamic variables are focused into sheets aligned with the magnetic field whose thickness is comparable to the dissipation scale. Sheets formed by oppositely directed waves are uncorrelated. We suspect that these are vortex sheets which the mean magnetic field prevents from rolling up.p> <p>8) Items (1)-(5) lend support to the model of strong MHD turbulence put forth by Goldreich and Sridhar (1995, 1997). Results from our simulations are also consistent with the GS prediction γ = 2/3. The sole not able discrepancy is that the 1D power law spectra, E(k_⊥) ∝ kp>-∝p>_⊥, determined from our simulations exhibit ∝ ≈ 3/2, whereas the GS model predicts ∝ = 5/3.p>

PICES Press, Vol. 19, No. 2, Summer 2011

•The 2011 Inter-sessional Science Board Meeting: A Note from Science Board Chairman (pp. 1-4) •Indicators for Status and Change within North Pacific Marine Ecosystems: A FUTURE Workshop (pp. 5-8) •PICES Calendar (p. 8) •2011 ESSAS Open Science Meeting (pp. 9-13) •The 5th Zooplankton Production Symposium (pp. 14-17) •Workshop on "Individual-Based Models of Zooplankton” (pp. 18-21) •New Book Release on the 100th Anniversary of the T/S Osharu Maru (p. 21) •Workshop on “Advances in Genomic and Molecular Studies of Zooplankton” (pp. 22-24) •Workshop on “Updates and Comparisons of Zooplankton Time Series” (pp. 25-27) •Workshop on “Impacts of Ocean Acidification on Zooplankton” (pp. 28-29) •Workshop on “Automated Visual Plankton Identification” (p. 30) •Professor Plum in the Dining Room with a Knife (p. 31) •PICES and ICES on the River Elbe (p. 32) •The State of the Western North Pacific in the Second Half of 2010 (pp. 33-34) •The Bering Sea: Current Status and Recent Events (pp. 35-37) •Northeast Pacific News (pp. 38-39) •PICES Advice on Marine Ecology at a Canadian Judicial Inquiry (p. 40)