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O projeto “A Câmara quer te ouvir” é um espaço de ouvir, onde o cidadão tem a oportunidade de dizer o que espera de seus representantes.

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  本书系统地介绍了微/纳米力学测试技术中最常用压入和划入技术及其典型应用。
全书共分13章。测量技术方面,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。

 

目录

 前言
第1章 绪论
1.1 硬度的定义和分类
1.2 纳米压入和划入技术的发展
1.3 纳米压入和划入技术的特点
参考文献
第2章 压入接触力学
2.1 弹性接触
2.2 弹塑性接触
参考文献
第3章 纳米压入测试原理
3.1 压入硬度和模量
3.2 连续刚度测量
3.3 载荷-深度数据确定的材料参数
参考文献
第4章 纳米压入测试方法
4.1 压针类型
4.2 测试环节
参考文献
第5章 纳米压入的确认和校准
5.1 直接确认和校准
5.2 间接校准
5.3 测试 和校准的实例
参考文献
第6章 纳米压入和划入的测量仪器
6.1 仪器技术指标的定义
6.2 美国MTS公司
6.3 美国Gysitron公司
6.4 瑞士CSM公司
6.5 英国MML公司
6.6 澳大利亚CSIRO公司
6.7 测量仪器的发展趋势
参考文献
第7章 力学参量的测量
7.1 压入方式
7.2 划入方式
7.3 弯曲方式
7.4 吸引方式
7.5 声发射测试
7.6 温度测试
参考文献
第8章 影响纳米压入测试的因素
8.1 测试仪器的影响
8.2 样品的表面状态和性质
8.3 纳米压入和划入测试所面临的问题
参考文献
第9章 在表面工程中的应用
第10章 在微机电系统中的应用
第11章 在生物及其相关材料
第12章 在高聚物中的应用
第13章 在金属玻璃中的应用
附录

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《边界层理论讲义》是郭永怀先生为中国科学技术大学近代力学系第一届学生讲授边界层理论所著的,经徐书轩和尹协远教授精心校订后,即将在庆祝中国科学技术大学成立50周年和纪念郭永怀先生牺牲40周年之际付印出版了。这是一件十分值得庆贺的事。
郭永怀先生是我国著名的力学和应用数学家,在流体力学和边界层理论方面有极深的造诣和重要的贡献。他又是一位热心的教育家。他和钱学森先生共同创建了中国科学技术大学近代力学系,积极倡导要在加强基础科学教育的同时把同学们带到学科的前沿。《边界层理论讲义》十分鲜明地体现了这种精神,在回顾流体力学基本方程和详细讲述低速边界层基本理论之后,紧接着便讲授低速湍流边界层和高速层流与湍流边界层理论,把同学们直接带进高速飞行面临的前沿科学领域。
“讲义”还体现了郭永怀先生一贯的严谨和精炼的作风和求实的科学精神。在短短的一百多页中,郭先生严密地论证和推导了边界层方程,讲述了湍流的基本特点及其在边界层方程式中的体现,介绍了基本的解法和典型解以及近似解法,指出了它们的适用范围。就其涉及内容的广度和深度而言,“讲义"已经超出教材的范围而成为一本学习和随时参考的专著了。“讲义”虽然著于四十余年前,但即使在计算技术高度发展的今天,仍不失其作为重要著作的价值。
“讲义”是郭先生留给我们的一份重要遗产,相信将受到广大读者的欢迎并进入我国科学家著作的宝库。

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Three major mass mortality events occurred on the upper Texas coast during 1994, from January through the second week of May. These events were distinguished by unusually large numbers of dead dolphins, sea turtles, and fishes washing ashore on Texas beaches. The beach stranding of dead animals began in January with bottlenose dolphins. By the end of March, 142 dolphins had washed ashore as compared to about 40 expected. By the latter part of April, dolphin mortalities declined but stranding of dead and comatose sea turtles increased. By the end of April, at least 127 sea turtles had stranded on the Texas coast since the beginning of the year, about double the expected number. Then, during May and June, a third mortality event began with a massive fish kill and more turtle deaths. By the middle of May, mortalities of all species as indicated by beach strandings returned to within expected levels. Nevertheless, 1994 stood out as a record year of marine mass mortalities in the northwestern Gulf of Mexico. (PDF file contains 94 pages.)

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The swordfish, Xiphias gladius, is a large migratory oceanic species. It is widely distributed in tropical, temperate, and sometimes cold waters of all oceans, and is usually found in areas with sea-surface temperatures above 13°C. It can reach a maximum size of 540 kg, and is a favorite food fish in many countries. It is excellent for steaks, canning, or teriyaki, the Japanese dish of meat grilled with sugar, soy sauce, and rice wine. Swordfish is harvested commercially throughout its distribution, in both coastal and high-seas fisheries. Sport fisheries for swordfish are very small compared to those for other billfishes, accounting for no more than a few hundred fish per year. (PDF file contains 284 pages.)

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The successful application of techniques to enhance detection of age marks in biological specimens is of vital importance in fisheries research. This manual documents age determination techniques used by staff at the Woods Hole Laboratory, National Marine Fisheries Service. General information on procedures for preparing anatomical structures is described, together with criteria used to interpret growth patterns and assign ages. Annotated photographs of age structures are provided to illustrate criteria. Detailed procedures are given for the following species: Atlantic herring (Clupea harengus), haddock (Melanogrammus aeglefinus), Atlantic cod (Gadus morhua), pollock (Pollachius virens), silver hake (Merluccius bilinearis), red hake (Urophycis chuss), black sea bass (Centropristis striata), weakfish (Cynoscion regalis), Atlantic mackerel (Scomber scombrus), butterfish (Peprilus triacanthus), redfish (Sebastes fasciatus), summer flounder (Paralichthys dentatus), winter flounder (Pseudopleuronectes americanus), witch flounder (Glyptocephalus cynoglossus), American plaice (Hippoglossoides platessoides), yellowtail flounder (Limanda ferruginea), surf clam (Spisula solidissima), and ocean quahog (Arctica islandica). (PDF file contains 142 pages.)

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[ES] Este artículo analiza los determinantes de la rentabilidad primaria de los bonos de titulización hipotecaria (conocidos en la literatura como mortgage backed securities, o MBS) emitidos en España durante el periodo 1993-2011, periodo en el que el mercado español llegó a convertirse en el más importante de Europa continental. Los resultados obtenidos sobre el análisis de la población completa de MBS emitidos (262 tramos configurados sobre 94 fondos de titulización) indican que la estructuración multitramo de los MBS ha ayudado a reducir el riesgo percibido global de las emisiones de MBS, mediante la generación de mercados más completos y la reducción de los problemas derivados de la existencia de asimetrías informativas implícitas en el proceso de selección de los activos transmitidos por parte de la entidad cedente. Esta reducción del riesgo percibido ha tenido un efecto directo sobre la rentabilidad ofrecida por los bonos de titulización emitidos. Además, no se encuentran evidencias de que la emisión de MBS persiga la transmisión efectiva de riesgos, más bien al contrario. Las Entidades de crédito, por lo general, han retenido los tramos de primeras pérdidas, lo que ha contribuido a mantener en niveles muy bajos (por debajo de la rentabilidad de la deuda soberana) la rentabilidad ofrecida por los MBS. Precisamente, el escaso diferencial ofrecido por los bonos de titulización se debe a que los tramos retenidos no han ofrecido primas de rentabilidad ajustadas al riesgo inherente.

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Primary objective was to map concentrations of target contaminants in the surfacial sediments. Secondary objectives included: characterization of potential sites for sediment capping demonstration projects, further characterization of sediment depositional and accumulation patterns, and estimation of historical contaminant inventories through sediment geochronology. (PDF contains 112 pages)

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Background: Human melanoma frequently colonizes bone marrow (BM) since its earliest stage of systemic dissemination, prior to clinical metastasis occurrence. However, how melanoma cell adhesion and proliferation mechanisms are regulated within bone marrow stromal cell (BMSC) microenvironment remain unclear. Consistent with the prometastatic role of inflammatory and angiogenic factors, several studies have reported elevated levels of cyclooxygenase-2 (COX-2) in melanoma although its pathogenic role in bone marrow melanoma metastasis is unknown. Methods: Herein we analyzed the effect of cyclooxygenase-2 (COX-2) inhibitor celecoxib in a model of generalized BM dissemination of left cardiac ventricle-injected B16 melanoma (B16M) cells into healthy and bacterial endotoxin lipopolysaccharide (LPS)-pretreated mice to induce inflammation. In addition, B16M and human A375 melanoma (A375M) cells were exposed to conditioned media from basal and LPS-treated primary cultured murine and human BMSCs, and the contribution of COX-2 to the adhesion and proliferation of melanoma cells was also studied. Results: Mice given one single intravenous injection of LPS 6 hour prior to cancer cells significantly increased B16M metastasis in BM compared to untreated mice; however, administration of oral celecoxib reduced BM metastasis incidence and volume in healthy mice, and almost completely abrogated LPS-dependent melanoma metastases. In vitro, untreated and LPS-treated murine and human BMSC-conditioned medium (CM) increased VCAM-1-dependent BMSC adherence and proliferation of B16M and A375M cells, respectively, as compared to basal medium-treated melanoma cells. Addition of celecoxib to both B16M and A375M cells abolished adhesion and proliferation increments induced by BMSC-CM. TNF alpha and VEGF secretion increased in the supernatant of LPS-treated BMSCs; however, anti-VEGF neutralizing antibodies added to B16M and A375M cells prior to LPS-treated BMSC-CM resulted in a complete abrogation of both adhesion-and proliferation-stimulating effect of BMSC on melanoma cells. Conversely, recombinant VEGF increased adherence to BMSC and proliferation of both B16M and A375M cells, compared to basal medium-treated cells, while addition of celecoxib neutralized VEGF effects on melanoma. Recombinant TNFa induced B16M production of VEGF via COX-2-dependent mechanism. Moreover, exogenous PGE2 also increased B16M cell adhesion to immobilized recombinant VCAM-1. Conclusions: We demonstrate the contribution of VEGF-induced tumor COX-2 to the regulation of adhesion-and proliferation-stimulating effects of TNFa, from endotoxin-activated bone marrow stromal cells, on VLA-4-expressing

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Lei nº 13.105, de 16 de março de 2015, que institui o Código de Processo Civil Brasileiro.

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Although the fishery on flounder in the German fishery zone in 2002 was characterised by good catch possibilities, a dramatic decrease of landings was observed because of marketing problems and low prices. Due to increasing international fishery pressure on flounder a quota system should be established in the future. The German flounder landings could be increased by a better marketing strategy to meet the optimal requirements for a reliable German quota. For 2003 the stock condition is expected to be good which could ensure a successful flounder fishery. It is necessary to stabilize the present technical measures for a better selection of the codend in the medium term.