A cassette of uncured composite materials with epoxy resin matrixes was exposed in the stratosphere (40 km altitude) over three days. Temperature variations of -76 to 32.5C and pressure up to 2.1 torr were recorded during flight. An analysis of the chemical structure of the composites showed, that the polymer matrix exposed in the stratosphere becomes crosslinked, while the ground control materials react by way of polymerization reaction of epoxy groups. The space irradiations are considered to be responsible for crosslinking of the uncured polymers exposed in the stratosphere. The composites were cured on Earth after landing. Analysis of the cured composites showed that the polymer matrix remains active under stratospheric conditions. The results can be used for predicting curing processes of polymer composites in a free space environment during an orbital space flight.

关键词：平流层；环氧基复合材料；环氧树脂；固化

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In this paper, software architecture for medical image processing, analysis and archiving is presented. On the basis of the considered architecture a new task-oriented medical image processing system, which allows imitating of the human visual system, is developed. The basic functions include input/output of halftone images, pre- and post-processing, filtration, compression, enhancement, 2D linear transforms, pseudo-color transforms, analysis and interpolations. Using the system features, various image processing tasks are semantically described in the experimental part. The main advantages of the proposed architecture are the use of adaptive algorithms for processing of medical images, tailored to their specific features.

关键词：图像处理；医学影像；软件架构；知识库系统

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It is shown by magnetic field dependent ac susceptibility, magnetic force microscopy, and ferromagnetic resonance that exposure of C(sub 60) to fluorine at 160 deg C produces a stable ferromagnetic material with a Curie temperature well above room temperature. The exposure to fluorine is accomplished by decomposing a fluorine rich polymer, trifluorochloroethylene, F(sub 2) (C-CFCl)(sub n) which has C(sub 60) imbedded in it. Based on previous experimental observations and molecular orbital calculations, it is suggested that the ferromagnetism is arising from crystals of C(sub 60)-F.

关键词：铁磁性；铁磁谐振；聚合物；拉曼光谱

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The study of fractures of glass, glassy type materials, and plastic has long been of interest to the forensic community. The focus of this interest has been the use of glass and polymer fractures to reconstruct past events and to associate items of evidence. One example of this association is the matching of glass fragments from various locations where they can be shown to have come from a common origin. In the materials science community, fractography is the means and methods for characterization of fractured specimens or components in order to study or identify the mechanism of such failures, which is the focus on most of the literature on the subject. The ability to show that each and every fracture is, in fact, unique has not been a matter of consequence or of interest to the engineering or scientific community. In contrast, the basic premise that fractures are not likely to be reproducible is very relevant to the forensic science community. The issue arises when a given fracture pattern is restored or component pieces are physically fitted together and 'matched' and the conclusion is drawn that this is unlikely to be possible unless all the components were derived from the same part. Despite the importance of this assumption, very limited research has actually been done to confirm that this is indeed the case. This study documented the very controlled fracture patterns of 60 glass panes, 60 glass bottles, and 60 plastic tail light lens covers. The pane and bottle specimens were fractured with three different types of penetration tips: sharp tip, round tip, and blunt tip.

关键词：聚合物；玻璃；玻璃破裂；断口；高分子材料

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关键词：化学；生物；实验室级芯片；环境监测

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关键词：无线通讯；贝叶斯过滤器；物联网技术；环境监测

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As the role of medical imaging in clinical diagnoses and treatment has been more and more important,CT scan has been applied more widely.How to extract abdominal artery from CT image automatically and accurately has a significant value for abdominal artery disease.Because the medical image is of complexity and diversity,traditional segmentation method cannot complete the segmentation task very well.Therefore,this paper presents a method for extracting abdominal artery from CT images using three-dimensional region growing algorithm combined with image morphology.The experimental results show that the proposed method is an effective way for improving the accuracy of abdominal artery segmentation.

关键词：疗用图像；三维图像；分割；区域生长；图像形态学

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Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1to as much as 10by 2050, the equivalent of 16-18of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

关键词：空气污染；温室气体；能源；环境影响

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关键词：环境监测；自然资源管理；栖息地

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This chapter discusses the utilization of polybenzoxazine/urethane alloys with fine-tuning properties for ballistic impact composite application. The ballistic impact study of Kevlar? fiber-reinforced polybenzoxazine alloys under the test weapon with standard 124 grains round lead projectile and a copper outer coating (Full Metal Jacket) typically used in the 9-mm handgun at an impact velocity of 426-431 m/s is reported. The polybenzoxazine/urethane alloy matrices at various urethane prepolymer contents were prepared to evaluate the effect of different urethane contents on the thermal, mechanical as well as ballistic resistant properties. Experimental results reveal a synergy in glass transition temperature and some mechanical properties of the alloys at the composition range of 10-30by weight of urethane fraction the thus provide a fascinating group of high temperature polymers with improved flexibility and enhanced a ballistic resistant characteristic.

关键词：聚苯并恶嗪；氨基甲酸乙酯；弹道性能；芳纶；高分子材料

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