加拿大安大略萨德伯里镍矿石中铂族元素地壳成因的锇同位素证据     

Dick.  AP 黄典豪 《国外矿床地质》1994,(1):44-52

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Biosensors for marine pollution research,monitoring and control     

Kröger S  Piletsky S  Turner AP 《Marine pollution bulletin》2002,45(1-12):24-34

Measurement of ecological, climatic and anthropogenic changes underpins the formulation of effective management strategies for sustainable use and protection of the marine environment. Sensors are traditionally used in marine studies to determine physical parameters, but there is increasing demand for real-time information about chemical and biological parameters. These parameters are currently measured in samples collected at sea and subsequently analysed in the laboratory. Biosensors fuse the exquisite sensitivity and specificity of living systems with the processing power of microelectronics to deliver simple, inexpensive measurement systems for use in the field or deployment in situ. While their potential for use in the marine environment is enormous, much published work to date has focussed on applications in freshwater and wastewater. Marine applications pose a substantial challenge in the robustness required for remote application, but recent developments in portable medical devices and receptor design suggest that these demands can now be realistically tackled.  相似文献   

地籍图与宗地图测绘方法探讨     

孙贤斌  肖本林 《测绘技术》1997,(2):51-53

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用双觇标建立竖直角折光模型的方法   总被引：1，自引：0，他引：1  

Pild.  AP  张剑平 《测绘技术》1989,(1):33-39

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A coupled soil-atmosphere model of H2O2 on Mars     

Bullock MA  Stoker CR  McKay CP  Zent AP 《Icarus》1994,107(1):142-154

The Viking Gas Chromatograph Mass Spectrometer failed to detect organic compounds on Mars, and both the Viking Labeled Release and the Viking Gas Exchange experiments indicated a reactive soil surface. These results have led to the widespread belief that there are oxidants in the martian soil. Since H2O2 is produced by photochemical processes in the atmosphere of Mars, and has been shown in the laboratory to reproduce closely the Viking LR results, it is a likely candidate for a martian soil oxidant. Here, we report on the results of a coupled soil/atmosphere transport model for H2O2 on Mars. Upon diffusing into the soil, its concentration is determined by the extent to which it is adsorbed and by the rate at which it is catalytically destroyed. An analytical model for calculating the distribution of H2O2 in the martian atmosphere and soil is developed. The concentration of H2O2 in the soil is shown to go to zero at a finite depth, a consequence of the nonlinear soil diffusion equation. The model is parameterized in terms of an unknown quantity, the lifetime of H2O2 against heterogeneous catalytic destruction in the soil. Calculated concentrations are compared with a H2O2 concentration of 30 nmoles/cm3, inferred from the Viking Labeled Release experiment. A significant result of this model is that for a wide range of H2O2 lifetimes (up to 10(5) years), the extinction depth was found to be less than 3 m. The maximum possible concentration in the top 4 cm is calculated to be approximately 240 nmoles/cm3, achieved with lifetimes of greater than 1000 years. Concentrations higher than 30 nmoles/cm3 require lifetimes of greater than 4.3 terrestrial years. For a wide range of H2O2 lifetimes, it was found that the atmospheric concentration is only weakly coupled with soil loss processes. Losses to the soil become significant only when lifetimes are less than a few hours. If there are depths below which H2O2 is not transported, it is plausible that organic compounds, protected from an oxidizing environment, may still exist. They would have been deposited by meteors, or be the organic remains of past life.  相似文献   

加拿大萨斯喀彻温钾盐矿的坑道雷达测深     

Anna.  AP 刘钊剡 《国外地质勘探技术》1989,(9):33-38

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流量演算的状态—空间模型（节译）     

Geor.  AP 刘德平 《水文科技情报》1991,8(1):37-41

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Hydrocarbon composition and distribution in a coastal region under influence of oil production in northeast Brazil   总被引：1，自引：0，他引：1  

Wagener Ade L  Carreira RS  Hamacher C  Scofield Ade L  Farias CO  Cordeiro LG  Luz LG  Baêta AP  Kalas FA 《Marine pollution bulletin》2011,62(8):1877-1882

Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10-50 ng L⁻¹ for ∑16PAH and 5-10 μg L⁻¹ for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5-10 ng g⁻¹for ∑16PAH and 0.01-5.0 μg g⁻¹ for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin.  相似文献   

IGCP项目280进展报告—地球上最古老的岩石     

Nutm.  AP 徐达 《国外地质(成都)》1992,(3):106-107

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根系生态护坡的有限元分析   总被引：2，自引：0，他引：2  

肖本林  罗寿龙  陈军  邓友生  郑建强 《岩土力学》2011,32(6):1881-1885

生态护坡是公路建设可持续发展的要求。根据林木根系对边坡浅层加筋锚固的原理,结合现场提取刺槐根系进行试验所得的基本参数,利用有限元软件ADINA进行分析。在模拟分析过程中,根系采用弹性杆件模型,土体采用摩尔-库仑模型,从坡度的变化对整个刺槐林边坡进行模拟计算,对其应力和应变场的变化进行分析。研究结果表明,刺槐群根能改善边坡浅层土体的应力、应变场,使坡体浅层更趋稳定;边坡坡度的增加会导致坡脚应力增大、坡肩处逐渐产生拉应力及其数值逐渐增大、应变集中区的范围也扩大,此时根系护坡效果减弱  相似文献