928 resultados para Border
Resumo:
Ejemplar dedicado a: Élites sociales y poder territorial.
The Intelligent Measuring Sub-System in the Computer Integrated and Flexible Laser Processing System
Resumo:
Based on the computer integrated and flexible laser processing system, develop the intelligent measuring sub-system. A novel model has been built to compensate the deviations of the main frame, a new-developed 3-D laser tracker system is applied to adjust the accuracy of the system. Analyzing the characteristic of all kinds of automobile dies, which is the main processing object of the laser processing system, classify the types of the surface and border needed to be measured and be processed. According to different types of surface and border, develop 2-D adaptive measuring method based on B?zier curve and 3-D adaptive measuring method based on spline curve. During the data processing, a new 3-D probe compensation method has been described in details. Some measuring experiments and laser processing experiments are carried out to testify the methods. All the methods have been applied in the computer integrated and flexible laser processing system invented by the Institute of Mechanics, CAS.
Resumo:
Pulsed laser beam was used to modify surface processing for ductile iron. The microstructures of processed specimen were observed using optical microscope (OM). Nanoindentation and micro-hardness of microstructures were measured from surface to inner of sample. The experimental results show that, modification zone is consisted of light melted zone, phase transformation hardening area and transient area. The light melt area is made up of coarse dendrite crystalline with a thickness less than 20um, phase transformation hardening area mainly of laminal or acicular martensite, retained austenite and graphite, i.e. M+A prime+ G. The cow-eye microstructure around graphite sphere always is formed in phase transformation hardening area zone, which consisting of a variety structure with the distance from the surface. So, it maybe as a obvious sign distinguishing modification zone border. Finally, the microstructures evolution of laser pulse processed ductile iron was analyzed coupling with beam energy distribution in space and laser pulse heating procession characteristics. The analysis shows that energy distribution of laser pulse has an important effect on microstructure during laser pulse modified ductile iron. Multi-scale and interlace arrangement are the important features for laser pulse modified ductile iron. Of microstructure.
Resumo:
Executive Summary: The western National Coastal Assessment (NCA-West) program of EPA, in conjunction with the NOAA National Ocean Service (NOS), conducted an assessment of the status of ecological condition of soft sediment habitats and overlying waters along the western U.S. continental shelf, between the target depths of 30 and 120 m, during June 2003. NCA-West and NOAA/NOS partnered with the West Coast states (Washington (WA), Oregon (OR), and California (CA)), and the Southern California Coastal Water Research Project (SCCWRP) Bight ’03 program to conduct the survey. A total of 257 stations were sampled from Cape Flattery, WA to the Mexican border using standard methods and indicators applied in previous coastal NCA projects. A key study feature was the incorporation of a stratified-random sampling design with stations stratified by state and National Marine Sanctuary (NMS) status. Each of the three states was represented by at least 50 random stations. There also were a total of 84 random stations located within NOAA’s five NMSs along the West Coast including the Olympic Coast NMS (OCNMS), Cordell Bank NMS (CBNMS), Gulf of Farallones NMS (GFNMS), Monterey Bay NMS (MBNMS), and Channel Islands NMS (CINMS). Collection of flatfish via hook-and-line for fish-tissue contaminant analysis was successful at 50 EMAP/NCA-West stations. Through a collaboration developed with the FRAM Division of the Northwest Fisheries Science Center, fish from an additional 63 stations in the same region and depth range were also analyzed for fish-tissue contaminants. Bottom depth throughout the region ranged from 28 m to 125 m for most stations. Two slightly deeper stations from the Southern California Bight (SCB) (131, 134 m) were included in the data set. About 44% of the survey area had sediments composed of sands (< 20% silt-clay), about 47% was composed of intermediate muddy sands (20-80% silt-clay), and about 9% was composed of muds (> 80% silt-clay). The majority of the survey area (97%) had relatively low percent total organic carbon (TOC) levels of < 2%, while a small portion (< 1%) had high TOC levels (> 5%), in a range potentially harmful to benthic fauna. Salinity of surface waters for 92% of the survey area were > 31 psu, with most stations < 31 psu associated with the Columbia River plume. Bottom salinities ranged only between 31.6 and 34.4 psu. There was virtually no difference in mean bottom salinities among states or between NMS and non-NMS stations. Temperatures of surface water (range 8.5 -19.9 °C) and bottom water (range 5.8 -14.7 °C) averaged several degrees higher in CA in comparison to WA and OR. The Δσt index of watercolumn stratification indicated that about 31% of the survey area had strong vertical stratification of the water column. The index was greatest for waters off WA and lowest for CA waters. Only about 2.6 % of the survey area had surface dissolved oxygen (DO) concentrations ≤ 4.8 mg/L, and there were no values below the lower threshold (2.3 mg/L) considered harmful to the survival and growth of marine animals. Surface DO concentrations were higher in WA and OR waters than in CA, and higher in the OC NMS than in the CA sanctuaries. An estimated 94.3% of the area had bottom-water DO concentrations ≤ 4.8 mg/L and 6.6% had concentrations ≤ 2.3 mg/L. The high prevalence of DO from 2.3 to 4.8 mg/L (85% of survey area) is believed to be associated with the upwelling of naturally low DO water across the West Coast shelf. Mean TSS and transmissivity in surface waters (excluding OR due to sample problems) were slightly higher and lower, respectively, for stations in WA than for those in CA. There was little difference in mean TSS or transmissivity between NMS and non-NMS locations. Mean transmissivity in bottom waters, though higher in comparison to surface waters, showed little difference among geographic regions or between NMS and non-NMS locations. Concentrations of nitrate + nitrite, ammonium, total dissolved inorganic nitrogen (DIN) and orthophosphate (P) in surface waters tended to be highest in CA compared to WA and OR, and higher in the CA NMS stations compared to CA non-sanctuary stations. Measurements of silicate in surface waters were limited to WA and CA (exclusive of the SCB) and showed that concentrations were similar between the two states and approximately twice as high in CA sanctuaries compared to OCNMS or nonsanctuary locations in either state. The elevated nutrient concentrations observed at CA NMS stations are consistent with the presence of strong upwelling at these sites at the time of sampling. Approximately 93% of the area had DIN/P values ≤ 16, indicative of nitrogen limitation. Mean DIN/P ratios were similar among the three states, although the mean for the OCNMS was less than half that of the CA sanctuaries or nonsanctuary locations. Concentrations of chlorophyll a in surface waters ranged from 0 to 28 μg L-1, with 50% of the area having values < 3.9 μg L-1 and 10% having values > 14.5 μg L-1. The mean concentration of chlorophyll a for CA was less than half that of WA and OR locations, and concentrations were lowest in non-sanctuary sites in CA and highest at the OCNMS. Shelf sediments throughout the survey area were relatively uncontaminated with the exception of a group of stations within the SCB. Overall, about 99% of the total survey area was rated in good condition (<5 chemicals measured above corresponding effect range low (ERL) concentrations). Only the pesticides 4,4′-DDE and total DDT exceeded corresponding effect range-median (ERM) values, all at stations in CA near Los Angeles. Ten other contaminants including seven metals (As, Cd, Cr, Cu, Hg, Ag, Zn), 2-methylnaphthalene, low molecular weight PAHs, and total PCBs exceeded corresponding ERLs. The most prevalent in terms of area were chromium (31%), arsenic (8%), 2-methylnaphthalene (6%), cadmium (5%), and mercury (4%). The chromium contamination may be related to natural background sources common to the region. The 2-methylnaphthalene exceedances were conspicuously grouped around the CINMS. The mercury exceedances were all at non-sanctuary sites in CA, particularly in the Los Angeles area. Concentrations of cadmium in fish tissues exceeded the lower end of EPA’s non-cancer, human-health-risk range at nine of 50 EMAP/NCA-West and nine of 60 FRAM groundfish-survey stations, including a total of seven NMS stations in CA and two in the OCNMS. The human-health guidelines for all other contaminants were only exceeded for total PCBs at one station located in WA near the mouth of the Columbia River. Benthic species richness was relatively high in these offshore assemblages, ranging from 19 to 190 taxa per 0.1-m2 grab and averaging 79 taxa/grab. The high species richness was reflected over large areas of the shelf and was nearly three times greater than levels observed in estuarine samples along the West Coast (e.g NCA-West estuarine mean of 26 taxa/grab). Mean species richness was highest off CA (94 taxa/grab) and lower in OR and WA (55 and 56 taxa/grab, respectively). Mean species richness was very similar between sanctuary vs. non-sanctuary stations for both the CA and OR/WA regions. Mean diversity index H′ was highest in CA (5.36) and lowest in WA (4.27). There were no major differences in mean H′ between sanctuary vs. nonsanctuary stations for both the CA and OR/WA regions. A total of 1,482 taxa (1,108 to species) and 99,135 individuals were identified region-wide. Polychaetes, crustaceans and molluscs were the dominant taxa, both by percent abundance (59%, 17%, 12% respectively) and percent species (44%, 25%, 17%, respectively). There were no major differences in the percent composition of benthic communities among states or between NMSs and corresponding non-sanctuary sites. Densities averaged 3,788 m-2, about 30% of the average density for West Coast estuaries. Mean density of benthic fauna in the present offshore survey, averaged by state, was highest in CA (4,351 m-2) and lowest in OR (2,310 m-2). Mean densities were slightly higher at NMS stations vs. non-sanctuary stations for both the CA and OR/WA regions. The 10 most abundant taxa were the polychaetes Mediomastus spp., Magelona longicornis, Spiophanes berkeleyorum, Spiophanes bombyx, Spiophanes duplex, and Prionospio jubata; the bivalve Axinopsida serricata, the ophiuroid Amphiodia urtica, the decapod Pinnixa occidentalis, and the ostracod Euphilomedes carcharodonta. Mediomastus spp. and A. serricata were the two most abundant taxa overall. Although many of these taxa have broad geographic distributions throughout the region, the same species were not ranked among the 10 most abundant taxa consistently across states. The closest similarities among states were between OR and WA. At least half of the 10 most abundant taxa in NMSs were also dominant in corresponding nonsanctuary waters. Many of the abundant benthic species have wide latitudinal distributions along the West Coast shelf, with some species ranging from southern CA into the Gulf of Alaska or even the Aleutians. Of the 39 taxa on the list of 50 most abundant taxa that could be identified to species level, 85% have been reported at least once from estuaries of CA, OR, or WA exclusive of Puget Sound. Such broad latitudinal and estuarine distributions are suggestive of wide habitat tolerances. Thirteen (1.2%) of the 1,108 identified species are nonindigenous, with another 121 species classified as cryptogenic (of uncertain origin), and 208 species unclassified with respect to potential invasiveness. Despite uncertainties of classification, the number and densities of nonindigenous species appear to be much lower on the shelf than in the estuarine ecosystems of the Pacific Coast. Spionid polychaetes and the ampharetid polychaete Anobothrus gracilis were a major component of the nonindigenous species collected on the shelf. NOAA’s five NMSs along the West Coast of the U.S. appeared to be in good ecological condition, based on the measured indicators, with no evidence of major anthropogenic impacts or unusual environmental qualities compared to nearby nonsanctuary waters. Benthic communities in sanctuaries resembled those in corresponding non-sanctuary waters, with similarly high levels of species richness and diversity and low incidence of nonindigenous species. Most oceanographic features were also similar between sanctuary and non-sanctuary locations. Exceptions (e.g., higher concentrations of some nutrients in sanctuaries along the CA coast) appeared to be attributable to natural upwelling events in the area at the time of sampling. In addition, sediments within the sanctuaries were relatively uncontaminated, with none of the samples having any measured chemical in excess of ERM values. The ERL value for chromium was exceeded in sediments at the OCNMS, but at a much lower percentage of stations (four of 30) compared to WA and OR non-sanctuary areas (31 of 70 stations). ERL values were exceeded for arsenic, cadmium, chromium, 2- methylnaphthalene, low molecular weight PAHs, total DDT, and 4,4′-DDE at multiple sites within the CINMS. However, cases where total DDT, 4,4′-DDE, and chromium exceeded the ERL values were notably less prevalent at CINMS than in non-sanctuary waters of CA. In contrast, 2-methylnaphthalene above the ERL was much more prevalent in sediments at the CINMS compared to non-sanctuary waters off the coast of CA. While there are natural background sources of PAHs from oil seeps throughout the SCB, this does not explain the higher incidence of 2-methylnaphthalene contamination around CINMS. Two stations in CINMS also had levels of TOC (> 5%) potentially harmful to benthic fauna, though none of these sites exhibited symptoms of impaired benthic condition. This study showed no major evidence of extensive biological impacts linked to measured stressors. There were only two stations, both in CA, where low numbers of benthic species, diversity, or total faunal abundance co-occurred with high sediment contamination or low DO in bottom water. Such general lack of concordance suggests that these offshore waters are currently in good condition, with the lower-end values of the various biological attributes representing parts of a normal reference range controlled by natural factors. Results of multiple linear regression, performed using full model procedures to test for effects of combined abiotic environmental factors, suggested that latitude and depth had significant influences on benthic variables regionwide. Latitude had a significant inverse influence on all three of the above benthic variables, i.e. with values increasing as latitude decreased (p< 0.01), while depth had a significant direct influence on diversity (p < 0.001) and inverse effect on density (p <0.01). None of these variables varied significantly in relation to sediment % fines (at p< 0.1), although in general there was a tendency for muddier sediments (higher % fines) to have lower species richness and diversity and higher densities than coarser sediments. Alternatively, it is possible that for some of these sites the lower values of benthic variables reflect symptoms of disturbance induced by other unmeasured stressors. The indicators in this study included measures of stressors (e.g., chemical contaminants, eutrophication) that are often associated with adverse biological impacts in shallower estuarine and inland ecosystems. However, there may be other sources of humaninduced stress in these offshore systems (e.g., bottom trawling) that pose greater risks to ambient living resources and which have not been captured. Future monitoring efforts in these offshore areas should include indicators of such alternative sources of disturbance. (137pp.) (PDF contains 167 pages)
Resumo:
ENGLISH: Yellowfin tuna, Neothunnus macropterus, and skipjack tuna, Katsuwonus pelamis, are fished intensively off the west coast of the Americas in an area from about the California-Mexico border in the north to the Peru-Chile border in the south. The historical development of this fishery, and its expansion by the long-range California fleets of bait and purse-seine vessels, are well documented by Godsil (1938), Scofield (1951) and Shimada and Sehaefer (1956). The quarterly distribution of the tuna catches within this area has been reported for some recent years by Alverson (1959). SPANISH: Los atunes aleta amarilla, Neothunnus macropterus, y barrilete, Katsuwonus pelamis, son pescados con intensidad frente a la costa occidental del continente americano, en un área comprendida más o menos entre la frontera California-México en el norte y el límite Perú-Chile en el sur. El desarrollo histórico de esta pesquería y la expansión que le han dado las flotas californianas de largo radio de acción, formadas por los barcos de carnada y rederos, están bien documentados por Godsil (1938), Scofield (1951) y Shimada y Schaefer (1956). La distribución trimestral de las pescas de atún dentro de esta área ha sido tratada por Alverson (1959) con referencia a años recientes.
Resumo:
border="0" alt="" hspace="6" width="100" height="139" align="left" /> 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。
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
2.1.1 Soeddon解
2.1.2锥形压针
2.1.3球形压针
2.1.4圆柱压针
2.2弹塑性接触
2.2.1塑性发生
2.2.2完全塑性
2.2.3材料响应
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载荷一深度数据确定的材料参数
3.3.1马氏硬度
3.3.2压入蠕变
3.3.3压入松弛
3.3.4压入弹性功和塑性功
参考文献
第4章 纳米压入测试方法
4.1压针类型
4.1.1玻氏压针
4.1.2立方角压针
4.1.3维氏压针
4.1.4努氏压针
4.1.5圆锥压针
4.1.6球形压针
4.1.7圆柱压针
4.1.8楔形压针
4.1.9考虑因素
4.2测试环节
4.2.1样品准备
4.2.2环境控制
4.2.3间距选择
4.2.4表面探测
4.2.5驱动方式
4.2.6测试步骤
4.2.7测试报告
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Mrs公司
6.3美国Hysitmn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
7.1.1硬度和模量
7.1.2断裂韧度
7.1.3蠕变和粘弹行为
7.1.4压入应力??应变曲线
7.1.5加卸载曲线涉及的
部分现象
7.2划人方式
7.2.1块体材料
7.2.2薄膜材料
7.2.3粗糙度
7.3弯曲方式
7.3.1微悬臂梁静载弯曲
7.3.2微桥静载弯曲
7.3.3微结构疲劳
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
8.1.1压针缺陷
8.1.2测试方法
8.1.3接触零点的确定
8.1.4载荷和位移的分辨力
8.2样品的表面状态和性质
8.2.1表面吸湿
8.2.2表面粗糙度
8.2.3残余应力
8.2.4凹陷和凸起变形
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
9.1金属材料表面激光强化的力学表征
9.2硬质膜的力学和摩擦学性能评估
9.2.1显微硬度测试
9.2.2纳米压人测试
9.2.3纳米划入测试
9.2.4膜材的影响
参考文献
第10章 在微机电系统中的应用
10.1薄膜测试
10.1.1典型薄膜材料的硬度和模量
10.1.2薄膜疲劳
10.1.3淀积工艺对二氧化硅薄膜力学性质的影响
10.2微结构弯曲
10.2.1微结构的静态弯曲
10.2.2微结构的动态弯曲
参考文献
第11章 在生物及其相关材料中的应用
11.1人工林杉木管胞细胞壁
11.2人体腰椎骨
11.3存储液对人体牙齿微力学性能的影响
参考文献
第12章 在高聚物中的应用
12.1PMMA单轴拉伸和弯曲力学行为
12.2划入测试的理论分析
12.3韧性行为的描述
12.4脆性行为的描述
12.4.1温度效应
12.4.2应变率效应
参考文献
第13章 在金属玻璃中的应用
13.1硬度和屈服应力的关系
13.2不连续的塑性变形
13.3压痕形貌和微结构变化
13.4应变率效应
13.5钕基金属玻璃的变形行为
参考文献
附录 常见问题的回答
1测试数量
2压入间距
3压入深度
4泊松比的选择
5典型材料的参数
6断裂韧度测试压针的选择
7纳米薄膜的测试
8典型材料的压入变形行为
9显微硬度和纳米压入硬度的关系
10压入影响区及其边界效应
10.1压入影响区的有限元模拟
10.2边界距离影响的有限元模拟
10.3压人间距影响的测试
参考文献
Resumo:
border="0" alt="" width="240" height="300" />
Resumo:
Resumo:
border="0" alt="" hspace="6" width="142" height="200" align="left" /> 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
Resumo:
Resumo:
border="0" alt="" hspace="6" width="83" height="120" align="left" />在我国生物力学是门新兴学科,它既是医学和生物医学工程发展的需要,也是力学学科发展的必然生物力学以医学、生理学、生物学的学要为出发点和归宿,把力学的和生物学的方法有机地结合起来,去解决这些学科工程中所需解决的问题
本书详细介绍了这方面的有关知识和研究成果
附录与关键词: 生物力学 概论 生物力学
目录
第一节 历史的源流第一章 生物力学概说
目录
第二节 背景和需要
第三节 全景鸟瞰
第二章 生物力学的力学基础
第一节 运动和力
2、1、1质点系动力学和刚体动力学基础
2、1、2刚体动力学在生物力学中的应用
2、1、3量纲和单位
2、2、1连续性假说
第二节 连续介质力学基本知识
2、2、2描述连续介质运动的两种方法
2、2、3应力
2、2、4应变·应变率
2、2、5变形功和应变能
2、2、6弹性和粘弹性
2、3、1流变学的方法学的一般原理
第三节 本构关系——流变学的主题
2、3、2Hooke(胡克)弹性体
2、3、3牛顿流体和非牛顿流体
2、3、4线性粘弹性体
2、4、1生命现象和流体运动
第四节 生物流体力学基础
2、4、2不同层次和不同系统中的生理流动问题
2、4、3流体力学的基本原理
2、4、4流体力学的基本方程
2、4、5量纲分析·相似参数
2、4、6生物流体力学的相似性问题
第五节 生物传质及其热力学基础
2、5、1热力学的基础定律
2、5、2扩散
2、5、3渗透·滤过
2、5、4组织间质中的渗流
2、5、5通过细胞膜的物质输运
结语:符号和语法
第三章 活组织的力学性质
第一节 骨的力学性质
3、2、1软组织的结构要素
第二节 软组织的力学性质
3、2、2软组织力学性质的实验方法
3、2、3软组织力学行为的一般特点
3、2、4软组织的本构方程
3、3、1血管壁的构造
第三节 血管的力学性质
3、3、2动脉血管的力学性质
3、3、3静脉血管的力学性质
3、3、4微血管的力学性质
第四节 关节 软骨的力学性质
3、4、1准线性粘弹性本构关系
3、4、2关节软骨的两相模型
3、5、1流体的粘弹性
第五节 生物粘弹性流体
3、5、2关节滑液的粘弹性
结语:生物流变学的理论和实践意义
第四章 肌肉力学基础
第一节 骨胳肌、心肌和平滑肌
第二节 骨胳肌的微结构和收缩机理
第三节 Hill方程和Hill模型
4、3、1Hill模型(双元素)
4、3、2三元素模型
4、4、1静息状态下心肌的力学性质
第四节 心肌的力学性质
4、4、2Hill模型应用于心肌
第五节 平滑肌的力学性质
结语:需要新概念、新技术
第五章 血液流变学导论
第一节 血液的流变特性
5、1、1宏观血液流变学的方法学原理
5、1、2血浆的粘度
5、1、3血液的粘性
5、1、4血液的粘弹性
第二节 血液非牛顿特性的细观和微观说明
第三节 红细胞的运动和变形
5、3、1红细胞的几何形状
5、3、2红细胞沉降——血沉
5、3、3红细胞的可变形性
5、3、4红细胞膜的力学性质
5、3、5红细胞聚集
5、4、1Fahreus—Lindqvist效应和Fahraeus效应
第四节 血液在微血管里的流变特性
5、4、2毛细血管内红细胞的运动和阻力
5、4、3毛细血管和毛细血管网络内红细胞的分布(比积的变化)
5、4、4表观粘度和相对粘度
5、5、1白细胞的力学性质
第五节 白细胞的流变行为
5、5、2白细胞在微血管里的流变行为
5、6、1血小板的活性与流变学因素
第六节 血小板功能行为的流变学问题
5、6、2凝血过程中血液的粘弹性
第七节 血液的本构方程
5、7、1几类粘弹性本构方程的述评
5、7、2可能的选择
结语:愿望和现实
第六章 心脏力学
第一节 心脏的构造和功能
第二节 心脏和心瓣的液体力学问题
6、2、1心脏和心瓣流体力学的若干基本问题
6、2、2二尖瓣的运动及其流场
6、2、3主动脉瓣的运动及其流场
6、3、1左心室的压力—容积关系
第三节 心脏的力学模型和泵功能
6、3、2左心室的应力和应变
6、3、3心脏的泵功能
6、4、1左心与动脉系统的相互作用
第四节 心脏与血管系统的相互作用
6、4、2左心系统和右心系统之间的相互作用
第五节 人造心脏瓣膜的生物力学问题
6、5、1人工心瓣的流体力学性能的检测和评价
6、5、2人工心瓣的疲劳寿命问题
结语:生物力学在生物医学工程中的位置
第七章 血液循环的力学规律
7、1、1分枝血管系统的阻力分布
第一节 动脉系统的阻力分布和分枝形态-Poiseuille定律的应用
7、1、2血管分枝形态的优化分析
7、2、1弹性直圆柱管里的定常层流
第二节 可变形管道内的定常流动
7、2、2血管的应力状态和弹性不稳定性
7、2、3可瘪管流动
7、2、4可变形管道内小扰动的传播
7、2、5三种流动的比较
7、2、6可变形管定常流动的稳定性问题
第三节 动脉血管里的脉动流和脉搏波
7、3、1脉搏波
7、3、2直圆柱管内的振荡流
第四节 脉搏波在动脉血管系统里的传播
7、4、1传输线理论——线性模型
7、4、2非线性数值模型
7、4、3中医脉象与脉搏波
7、5、1大动脉中流动的一般特点
第五节 大动脉里的流动
7、5、2动脉粥样硬化与血液流动的动力特性
7、5、3弯曲对大血管流动的影响
7、5、4分枝管道的流动
7、5、5动脉狭窄的流体力学问题
7、5、6血管分枝、弯曲、截面积突变部位红细胞和血小板的运动
第六节 静脉血管里的流动
7、6、1静脉血管的力学性质
7、6、2静脉中的脉动流和波动
7、6、3瓣膜对静脉血流的影响
第七节 微循环力学
7、7、1微循环的几种构造模式
7、7、2微循环力学参数的在体观测
7、7、3微循环力学问题概述
7、7、4毛细血流与周围组织之间的物质输运
第八节 肺血流的力学规律
7、8、1肺血管系统的几何形态
7、8、2肺血管力学性质
7、8、3肺毛细血管组织内的流动——片流模型
7、8、4肺毛细血管组织中血液的表观粘度
7、8、5肺血流的阻力
7、8、6理论的实验检验
结语:一个必然的趋势
第八章 呼吸力学
第一节 呼吸道内的空气流动
8、1、1呼吸道的阻力
8、1、2上呼吸道里的流动
8、1、3呼吸系统的动力学行为
第二节 支气管里的对流扩散
第三节 肺泡内气体的扩散
第四节 肺泡和毛细血流之间的气体交换
8、4、1通过膜的气体扩散
8、4、2肺泡—红细胞之间的气体交换
8、4、3扩散容量的实验测定
8、4、4肺通气量与血流量的关系
第五节 肺功能的宏观评价
第六节 肺呼气流量极限
第九章 器官力学的几个不同方面
第一节 耳蜗力学
9、1、1耳蜗的解剖特点和超微结构
9、1、2耳蜗管内的波传播
9、1、3小振幅下的非线性响应
第二节 脊柱力学
9、2、1脊柱的力学性质
9、2、2腰椎的受力分析
9、2、3脊柱的冲击损伤
9、3、1冲击和弹性波
第三节 肺的冲击损伤
9、3、2冲击载荷引起的肺水肿
9、3、3关于冲击损伤引起肺水肿的机理
结语:方法·概念·诀窃
第十章 应力和生长
第一节 从零应力状态到应力——生长假说
10、2、1心脏肥大
10、2、2肺的重建
第二节 软组织和器官的重建
10、2、3血管的重建
第三节 结构—功能适应性原理在骨生物力学中的体现
10、3、1骨折的愈合
10、3、2骨组织的重建
10、4、1血液流动对血管内皮细胞的影响
第四节 流体动力对细胞生长的影响
10、4、2流体动力对离体培养的血管内皮细胞生长的影响
结语:未来的新天地
Resumo:
border="0" alt="" hspace="8" width="141" height="200" align="left" />The microgravity research, as a branch of the advanced sciences and a spe- cialized field of high technology, has been made in China since the late 1980's. The research group investigating microgravity fluid physics consisted of our col- leagues and the authors in the Institute of Mechanics of the Chinese Academy of Sciences (CAS), and we pay special attention to the floating zone convection as our first research priority. Now, the research group has expanded and is a part of the National Microgravity Laboratory of the CAS, and the research fields have been extended to include more subjects related to microgravity science. Howev- er, the floating zone convection is still an important topic that greatly holds our research interests.
目录
1.1 floating-zone crystal growth
1.2 physical model
1.3 hydrodynamic model
1.4 mathematical model
references
2. basic features of floating zone convection
2.1 equations and boundary conditions
2.2 simple solutions of fz convection
2.3 solution for two-layers flow
2.4 numerical simulation
2.5 onset of oscillation
references
3. experimental method of fz convection
3.1 ground-based simulation experiments for pr≥1
3.2 temperature and velocity oscillations
3.3 optical diagnostics of free surface oscillation
3.4 critical parameters
3.5 microgravity experiments
3.6 ground-based simulation experiment for pr《1
4. mechanism on the onset of oscillatory convection
4.1 order of magnitude analysis
4.2 mechanism of hydrothermal instability
4.3 linear stability analysis
4.4 energy instability of thermocapillary convection
4.5 unsteady numerical simulation of 2d and 3d
4.6 two bifurcation transitions in the case of small pr number fluid
4.7 two bifurcation transitions in the case of large pr number fluid
4.8 transition to turbulence
references
5. liquid bridge volume as a critical geometrical parameter
5.1 critical geometrical parameters
5.2 ground-based and mierogravity experiments
5.3 instability analyses of a large prandtl number (pr≥1)fluid
5.4 instability analyses of a small prandtl number (pr《1)fluid
5.5 numerical simulation on two bifurcation process
references
6. theoretical model of crystal growth by the floating zone method
6.1 concentration distribution in a pure diffusion process
6.2 solutal capillary convection and diffusion
6.3 coupling with phase change convection
6.4 engineering model of floating zone technique
references
7. influence of applied magnetic field on the fz convection
7.1 striation due to the time-dependent convection
7.2 applied steady magnetic field and rotational magnetic field
7.3 magnetic field design for floating half zone
7.4 influence of magnetic field on segregation
references
8. influence of residual acceleration and g-jitter
8.1 residual acceleration in microgravity experiments
8.2 order of magnitude analyses (oma)
8.3 rayleigh instability due to residual acceleration
8.4 ground-based experiment affected by a vibration field
8.5 numerical simulation of a low frequency g-jitter
8.6 numerical simulation of a high frequency g-jitter
references
Resumo:
border="0" alt="" hspace="6" width="122" height="180" align="left" />本书以集成化激光智能加工系统为基础对智能激光加工领域作了开拓性的介绍。 全书共分7章。分别介绍了集成化激光智能加工系统的内涵、特点和发展趋势,激光加工工程的理论基础,柔性激光加工技术及其生产系统,激光加工机器人系统,智能测量技术,集成化智能控制,激光智能加工系统的实时在线监控。 本书主要供高等院校相关专业的本科生、硕士、博士研究生、博士后、教师和科研院所以及相关部门的科研人员使用,也可供工业界、企业界的科技管理和工程技术人员参考。
目录
一 导论
1 绪言
2 激光加工概论
……
二 激光加工原理
1 激光原理
……
三 激光柔性加工工程
1 几种常用的工业激光器
……
四 激光加工机器人系统
1 五维框架式工业机器人工作原理
……
五 智能测量工程
1 智能测量
……
六 智能控制系统的集成
1 智能控制的集成
……
七 实时在线监控
1 实时在线监控的重要性
……
参考文献
Resumo:
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。
Resumo:
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