991 resultados para 140.3480


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Parte 1 - Leis

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Atualizada até 18/7/2014

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Thirty sites were sampled in southern Biscayne Bay and Manatee Bay in December 1999 to determine the extent of toxicity in sediments. Analyses and assays included: pesticides and phenols in seawater; chemical contaminants in sediment; amphipod mortality, HRGS P450, sea urchin sperm fertilization and embryology, MicrotoxTM, MutatoxTM, grass shrimp AChE and juvenile clam mortality assays; sea urchin sperm, amphipod and oyster DNA damage; and benthic community assessment. Sediment sites near the mouth of canals showed evidence of contamination. Contaminant plumes and associated toxicity do not appear to extend seaward of the mouth of the canals in an appreciable manner. Concentrations of contaminants in the sediments in open areas of Biscayne and Manatee Bays are generally low. (PDF contains 140 pages)

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From July 1965 to June 1964 the Natural Resources Institute's Research Vessel ORION took 16 minute tows with a forty (40) foot otter trawl net at 38 selected locations in Chesapeake Bay from the south of the Potomac River to Turkey Point at the head of the Bay and including some tributaries. Shallow and deep hauls were taken at most stations with depths ranging from 5 to 140 feet. A schematic summary of the 54 different species caught was compared with "Fishes of the Chesapeake Bay" by S. F. Hildebrand and W. C. Schroeder. Sixteen species including five not contained in the above references were selected for discussion. (PDF contains 21 pages)

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Between 1994 and 1997, 258 tissue and 178 sediment samples were analyzed for chlorpyrifos throughout the coastal United States and the Great Lakes. Subsequently, 95 of the 1997 tissue samples were reanalyzed for endosulfan. Tissue chlorpyrifos concentrations, which exceeded the 90th percentile, were found in coastal regions known to have high agricultural use rates but also strongly correlated with sites near high population. The highest concentrations of endosulfans in contrast, were generally limited to agricultural regions of the country. Detections of chlorpyrifos at several Alaskan sites suggest an atmospheric transport mechanism. Many Great Lakes sites had chlorpyrifos tissue concentrations above the 90th percentile which decreased with increasing distance from the Corn Belt region (Iowa, Indiana, Illinois, and Wisconsin) where most agriculturally applied chlorpyrifos is used. Correlation analysis suggests that fluvial discharge is the primary transport pathway on the Atlantic and Gulf of Mexico coasts for chlorpyrifos but not necessarily for endosulfans. (PDF contains 28 pages)

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Executive Summary: Information found in this report covers the years 1986 through 2005. Mussel Watch began monitoring a suite of trace metals and organic contaminants such as DDT, PCBs and PAHs. Through time additional chemicals were added, and today approximately 140 analytes are monitored. The Mussel Watch Program is the longest running estuarine and coastal pollutant monitoring effort conducted in the United States that is national in scope each year. Hundreds of scientific journal articles and technical reports based on Mussel Watch data have been written; however, this report is the first that presents local, regional and national findings across all years in a Quick Reference format, suitable for use by policy makers, scientists, resource managers and the general public. Pollution often starts at the local scale where high concentrations point to a specific source of contamination, yet some contaminants such as PCBs are atmospherically transported across regional and national scales, resulting in contamination far from their origin. Findings presented here showed few national trends for trace metals and decreasing trends for most organic contaminants; however, a wide variety of trends, both increasing and decreasing, emerge at regional and local levels. For most organic contaminants, trends have resulted from state and federal regulation. The highest concentrations for both metal and organic contaminants are found near urban and industrial areas. In addition to monitoring throughout the nation’s coastal shores and Great Lakes, Mussel Watch samples are stored in a specimen bank so that trends can be determined retrospectively for new and emerging contaminants of concern. For example, there is heightened awareness of a group of flame retardants that are finding their way into the marine environment. These compounds, known as polybrominated diphenyl ethers (PBDEs), are now being studied using historic samples from the specimen bank and current samples to determine their spatial distribution. We will continue to use this kind of investigation to assess new contaminant threats. We hope you find this document to be valuable, and that you continue to look towards the Mussel Watch Program for information on the condition of your coastal waters. (PDF contains 118 pages)

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El origen es una de las estrategias utilizadas tradicionalmente por parte de los productos agroalimentarios para diferenciar una oferta de otra en el mercado. En nuestro país existen más de 140 Indicaciones de Origen reconocidas por la Comisión Europea que abarcan diferentes alimentos y bebidas. De todas ellas, las seis denominaciones de jamón existentes aportan casi el 15% del valor económico conjunto, aún suponiendo únicamente el 4,26% del total. A partir del análisis cuantitativo, y del desarrollo de un análisis DAFO del sector, se realiza una reflexión acerca del papel que el origen puede jugar como elemento de diferenciación y se ofrecen recomendaciones prácticas para incrementar el conocimiento y la notoriedad de las denominaciones en el mercado

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This is the report of a livelihoods study team working together with villagers from Trorbek Pork in Kandal Province, Cambodia. The livelihoods study is based on the current population census (1998) and key informant interviews: 10 to 70 villagers (50% women) representing the 140 families of Trorbek Pork Village, Kampong Kong Commune, Koh Thom District, Kandal Province. (PDF contains 40 pages)

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本书阐明了板壳断裂理论的基础。论证了Reissner型板壳断裂理论的科学性、经典板壳断裂理论的缺陷及在一定范围内仍具有的实用价值;介绍了作者所创意的研究Reissner型板壳断裂纹尖端场的方法等。

目录

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Adiabatic shear localization is a mode of failure that occurs in dynamic loading. It is characterized by thermal softening occurring over a very narrow region of a material and is usually a precursor to ductile fracture and catastrophic failure. This reference source is the first detailed study of the mechanics and modes of adiabatic shear localization in solids, and provides a systematic description of a number of aspects of adiabatic shear banding. The inclusion of the appendices which provide a quick reference section and a comprehensive collection of thermomechanical data allows rapid access and understanding of the subject and its phenomena. The concepts and techniques described in this work can usefully be applied to solve a multitude of problems encountered by those investigating fracture and damage in materials, impact dynamics, metal working and other areas. This reference book has come about in response to the pressing demand of mechanical and metallurgical engineers for a high quality summary of the knowledge gained over the last twenty years. While fulfilling this requirement, the book is also of great interest to academics and researchers into materials performance.

Table of Contents

1Introduction1
1.1What is an Adiabatic Shear Band?1
1.2The Importance of Adiabatic Shear Bands6
1.3Where Adiabatic Shear Bands Occur10
1.4Historical Aspects of Shear Bands11
1.5Adiabatic Shear Bands and Fracture Maps14
1.6Scope of the Book20
2Characteristic Aspects of Adiabatic Shear Bands24
2.1General Features24
2.2Deformed Bands27
2.3Transformed Bands28
2.4Variables Relevant to Adiabatic Shear Banding35
2.5Adiabatic Shear Bands in Non-Metals44
3Fracture and Damage Related to Adiabatic Shear Bands54
3.1Adiabatic Shear Band Induced Fracture54
3.2Microscopic Damage in Adiabatic Shear Bands57
3.3Metallurgical Implications69
3.4Effects of Stress State73
4Testing Methods76
4.1General Requirements and Remarks76
4.2Dynamic Torsion Tests80
4.3Dynamic Compression Tests91
4.4Contained Cylinder Tests95
4.5Transient Measurements98
5Constitutive Equations104
5.1Effect of Strain Rate on Stress-Strain Behaviour104
5.2Strain-Rate History Effects110
5.3Effect of Temperature on Stress-Strain Behaviour114
5.4Constitutive Equations for Non-Metals124
6Occurrence of Adiabatic Shear Bands125
6.1Empirical Criteria125
6.2One-Dimensional Equations and Linear Instability Analysis134
6.3Localization Analysis140
6.4Experimental Verification146
7Formation and Evolution of Shear Bands155
7.1Post-Instability Phenomena156
7.2Scaling and Approximations162
7.3Wave Trapping and Viscous Dissipation167
7.4The Intermediate Stage and the Formation of Adiabatic Shear Bands171
7.5Late Stage Behaviour and Post-Mortem Morphology179
7.6Adiabatic Shear Bands in Multi-Dimensional Stress States187
8Numerical Studies of Adiabatic Shear Bands194
8.1Objects, Problems and Techniques Involved in Numerical Simulations194
8.2One-Dimensional Simulation of Adiabatic Shear Banding199
8.3Simulation with Adaptive Finite Element Methods213
8.4Adiabatic Shear Bands in the Plane Strain Stress State218
9Selected Topics in Impact Dynamics229
9.1Planar Impact230
9.2Fragmentation237
9.3Penetration244
9.4Erosion255
9.5Ignition of Explosives261
9.6Explosive Welding268
10Selected Topics in Metalworking273
10.1Classification of Processes273
10.2Upsetting276
10.3Metalcutting286
10.4Blanking293
 Appendices297
AQuick Reference298
BSpecific Heat and Thermal Conductivity301
CThermal Softening and Related Temperature Dependence312
DMaterials Showing Adiabatic Shear Bands335
ESpecification of Selected Materials Showing Adiabatic Shear Bands341
FConversion Factors357
 References358
 Author Index369
 Subject Index375

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From the mid-1950's to the mid-1960's a series of quantitative surveys of the macrobenthic invertebrate fauna were conducted in the offshore New England region (Maine to Long Island, New York). The surveys were designed to 1) obtain measures of macrobenthic standing crop expressed in terms of density and biomass; 2) determine the taxonomic composition of the fauna (ca. 567 species); 3) map the general features of macrobenthic distribution; and 4) evaluate the fauna's relationships to water depth, bottom type, temperature range, and sediment organic carbon content. A total of 1,076 samples, ranging from 3 to 3,974 m in depth, were obtained and analyzed. The aggregate macrobenthic fauna consists of 44 major taxonomic groups (phyla, classes, orders). A striking fact is that only five of those groups (belonging to four phyla) account for over 80% of both total biomass and number of individuals of the macrobenthos. The five dominant groups are Bivalvia, Annelida, Amphipoda, Echninoidea, and Holothuroidea. Other salient features pertaining to the macrobenthos of the region are the following: substantial differences in quantity exist among different geographic subareas within the region, but with a general trend that both density and biomass increase from northeast to southwest; both density and biomass decrease with increasing depth; the composition of the bottom sediments significantly influences both the kind and quantity of macrobenthic invertebrates, the largest quantities of both measures of abundance occurring in the coarser grained sediments and diminishing with decreasing particle size; areas with marked seasonal changes in water temperature support an abundant and diverse fauna, whereas a uniform temperature regime is associated with a sparse, less diverse fauna; and no detectable trends are evident in the quantitative composition of the macrobenthos in relation to sediment organic carbon content. (PDF file contains 246 pages.)

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Daytime feeding behavior of humpback whales (Megaptera novaeangliae) in Gulf of the Farallones, California, and adjacent waters was observed during autumn of 1988 to 1990. Bodega Canyon, Cordell Bank, and the Farallon Islands were the primary sites of feeding activity. Fecal samples of whales and zooplankton tows contained euphausiids exclusively, dominated by Thysanoessa spinifera (79%), with lesser amounts of Euphausia pacifica (14%), Nyctiphanes simplex (4%), and Nematoscelis difficilis (3%). In 1988 and 1990, whales also were infrequently observed feeding on small schooling fish, presumably Pacific herring (Clupea pallasii), northern anchovy (Engraulis mordax), and juvenile rockfish (Sebastes spp.). Feeding was the most common behavior observed (52%), and less frequently traveling (23%), milling (21 %), and resting (4%). Whales used different methods to consume euphausiid prey at the surface (0-10 m), in shallow water (11-60 m), and deep water (61-140 m). Humpback whales fed at the surface 56% of time in 1988 and 32% of time in 1990, using primarily lateral lunges to capture swarms of euphausiids. In 1989, no surface feeding was observed; however, deep, long-duration dives were followed by extended surface intervals with many respirations. These 1989 observations coincided with increased prey depth as indicated by depth sounder records of diving whales and prey scattering layers. In 1989, increased prey depth and associated feeding behaviors were strongly associated with unusually high surface temperatures, calm seas, and changes in water circulation. Environmental conditions in 1989 triggered the most intense and wide-spread occurrence of red tide in this region since 1980. Red tide samples collected throughout this period contained Alexandrium (=Gonyaulax) catenella and Noctiluca scintillans. Surface feeding was observed only in 1988 and 1990, when surface prey were available and red tides were very limited in extent, duration, and intensity. Annual variations in humpback whale feeding behavior were related to prey availability which is affected by corresponding environmental conditions. (PDF contains 94 pages)