意大利亚平宁挤压带南部的大规模纵向伸展作用

在晚新生代的逆冲作用期间，亚平宁南部的环第勒尼安造山带的内部经历了两期近垂直的伸展作用。早期的伸展作用伴随不断增强的逆冲带的弧形弯曲作用形成，其方向平行于构造轴，构造带的长度增加了５０％，这种纵向应变伴随着一些低角度正断层集中在构造域内，记录了达１５０－２００％的伸展量。晚期的伸展作用与造山带呈较高角度，该期的伸展伴随着上新世一更新世的上升隆起和第勒尼安海裂谷作用向东南方向的移动。     

Reobserving the Extreme-Ultraviolet Emission from Abell 2199: In Situ Measurement of Background Distribution by Offset Pointing

The EUV excess emission from the clusters A2199 and A1795 remains an unexplained astrophysical phenomenon. There has been many unsuccessful attempts to "trivialize" the findings. In this Letter, we present direct evidence proving that the most recent of such attempts, which attributes the detected signals to a background nonuniformity effect, is likewise excluded. We address the issue by a reobservation of A2199 that features a new filter orientation, usage of a more sensitive part of the detector, and, most crucially, the inclusion of a background pointing at approximately 2 degrees offset-the first in situ measurement of its kind. We first demonstrate quantitatively two facts: (1) the offset pointing provides an accurate background template for the cluster observation, while (2) data from other blank fields do not. We then performed a point-to-point subtraction of the in situ background from the cluster field, with an appropriate propagation of errors. The resulting cluster radial profile is consistent with that obtained by our original method of subtracting a flat asymptotic background. The emission now extends to a radius of 20&arcmin;; it confirms the rising prominence of EUV excess beyond approximately 5&arcmin; as previously reported.     

Evaluation of bioremediation strategies of a controlled oil release in a wetland

A controlled petroleum release was conducted to evaluate bioremediation in a wetland near Houston, Texas. The 140-day study was conducted using a randomized, complete block design to test three treatments with six replicates per treatment. The three treatment strategies were inorganic nutrients, inorganic nutrients with an alternative electron acceptor, and a no-action oiled control. Samples were analyzed for petroleum chemistry and inorganic nutrients. These results are discussed in the context of our related research involving toxicology and microbiology at the site during the experiment. To evaluate biodegradation, the targeted compounds were normalized to the conservative compound C3017alpha, 21beta-[H]hopane, thus reducing the effects of spatial heterogeneity and physical transport. The two biostimulation treatments demonstrated statistically-higher rates of biodegradation than the oiled no-action control. For the majority of the experiment, target nutrient levels were maintained. Further research may be warranted to optimize these bioremediation strategies as well as evaluating additional treatment strategies for wetlands and other shoreline systems.     

Measurement of copper release rates from antifouling paint under laboratory and in situ conditions: implications for loading estimation to marine water bodies

The release of biocides, such as copper (Cu), from antifouling (AF) coatings on vessel hulls represents a significant proportion of overall Cu loading in those harbors and estuaries where substantial numbers of small craft or large vessels are berthed. Copper release rates were measured on several self-polishing, tin-free coatings and an ablative Cu reference coating applied to steel panels using three measurement methods. The panels were exposed in natural seawater in San Diego Bay, and release rates were measured both in the laboratory and field over 2 years. Results with the static (20 cm x 30 cm) panels indicated that Cu release rates were initially high (25-65 microg Cu cm(-2)day(-1)), with a large range of values between paint types. Release rates declined to substantially lower rates (8-22 microg cm(-2)day(-1)) with reduced variability within 2 months. Release rates continued to decrease over time for approximately 6 months when relatively constant release rates were observed for most coatings. Over time, relative differences in Cu release rates measured by three exposure methods decreased, with all coatings exhibiting similar behavior toward the end of the study. Lowest overall Cu release rates were observed with the self-polishing experimental paint no. 7 in static-dynamic and in situ treatments. The highest periodic release rates were measured from panels that experienced periods of both static and dynamic exposure (8.7 ms(-1) rotation). The lowest release rates were measured from panels that experienced static, constant depth exposure, and where release rates were evaluated in situ, using a novel diver-deployed measurement system. Results from this in situ technique suggests that it more closely reflects actual Cu release rates on vessel hulls measured with intact natural biofilms under ambient conditions than measurements using standardized laboratory release rate methods. In situ measurements made directly on the AF surface of vessels demonstrated typically lower release rates than from the panel studies, averaging 8.2 microg cm(-2)day(-1) on pleasure craft, and 3.8 microg cm(-2)day(-1) on Navy vessels. The data suggest that the presence of an established biofilm likely serves to moderate the release of Cu from field-exposed antifouling coatings both on panels and hull surfaces.     

综合气象观测运行监控业务及系统升级设计

通过对综合气象观测运行监控业务及运行监控系统现状的分析,提出了运行监控业务的发展设想,并对运行监控系统升级做了科学的设计。结果指出,运行监控业务将成为装备保障工作的核心中枢,具有监控、指挥、调度、管理功能,应形成设备监控、维修保障、装备供应与评估业务关联互动的业务体系。运行监控系统需突破目前依赖观测资料质量检查为主要手段的技术,建立以设备自身状态信息为主,故障维修业务填报信息和观测资料检查等多元信息相互校验的技术,实现监控、维修保障、装备供应的信息联动。     

基于数字高程模型的公路勘察设计

根据公路勘测设计的特点,阐述了数字高程模型(DEM)的概念和特点以及数字高程模型的建模方式,讨论了适应于公路勘查设计的数字高程模型数据采集方法等问题,总结了数字高程模型在公路勘察设计中的应用。     

MTBE and gasoline hydrocarbons in ground water of the United States

The occurrence of methyl tert-butyl ether (MTBE) and gasoline hydrocarbons was examined in three types of studies of ground water conducted by the U.S. Geological Survey: major aquifer surveys, urban land-use studies, and agricultural land-use studies. The detection frequency of MTBE was dependent on the study type, with the highest detection frequency in urban land-use studies. Only 13 ground water samples from all study types, or 0.3%, had concentrations of MTBE that exceeded the lower limit of the U.S. EPA's Drinking-Water Advisory. The detection frequency of MTBE was highest in monitoring wells located in urban areas and in public supply wells. The detection frequency of any gasoline hydrocarbon also was dependent on study type and generally was less than the detection frequency of MTBE. The probability of detecting MTBE in ground water was strongly associated with population density, use of MTBE in gasoline, and recharge. Ground water in areas with high population density, in areas where MTBE is used as a gasoline oxygenate, and in areas with high recharge rates had a greater probability of MTBE occurrence. Also, ground water from public supply wells and shallow ground water underlying urban land-use areas had a greater probability of MTBE occurrence compared to ground water from domestic wells and ground water underlying rural land-use areas. The probability of detecting MTBE in ground water was weakly associated with the density of leaking underground storage tanks, soil permeability, and aquifer consolidation, and only concentrations of MTBE >0.5 microg/L were associated with dissolved oxygen.