The Western Pearl River Delta: Growth and Opportunities for Cooperative Development with Hong Kong by Y. M. Yeung,Shen Jianfa,and Zhang Li     

Mike Rudibaugh 《The Professional geographer》2007,59(3):397-398

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利用AutoPrep技术抑制型电导离子色谱法检测土壤中碘     

刘肖  史亚利Archava Siriraks Mike Kinderman 《岩矿测试》2007,26(6):446-450

利用AutoPrep自动样品前处理技术，对土壤燃烧吸收液进行在线预浓缩，抑制型电导进行检测，建立了一种全新思路的检测土壤样品中碘的方法。选择亲水性非常强的氢氧化物选择性IonPac AS16阴离子交换色谱柱，淋洗液发生装置在线产生KOH进行等梯度淋洗，抑制型电导检测。结果表明，对于土壤燃烧吸收液中碘离子的测定，方法检出限（S／N=3）可达1．2μg/L，线性相关系数为0．9998，方法精密度（RSD，n=7）为1．161％～4．566％，回收率在90．6％～100．8％。采用AutoPrep电导检测和脉冲安培检测离子色谱法测定不同土壤样品中的碘，两种方法的检测结果基本一致。方法在提供了稳定的系统空白的同时，还具备自动化程度高、操作简单、重现性好、灵敏度高、系统稳定、节约时间、成本低廉和对环境友好等多方面特点，适合于大批量土壤普查中碘的分析。  相似文献   

Space exploration and the RAS     

Mike Hapgood  Ian Crawford 《Astronomy& Geophysics》2007,48(6):6.9-6.10

Mike Hapgood and Ian Crawford assess the relevance of the BNSC UKSEWG Report for the Royal Astronomical Society.  相似文献   

Editorial Note     

Mike Parnwell  & Jonathan Rigg 《Singapore journal of tropical geography》2001,22(3):205-211

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SCAP meeting no.10     

Mike Bode  Phil Charles  Carlos Frenk 《Astronomy& Geophysics》2001,42(2):2.27-2.28

Mike Bode , Phil Charles and Carlos Frenk report the minutes of the tenth meeting of the Standing Conference of Astronomy Professors, held at the RAS, Burlington House on 30 January 2001.  相似文献   

Potential Water-Quality Impact of Hard-Rock Mining     

Mike Wireman 《Ground Water Monitoring & Remediation》2001,21(3):40-51

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A 1951–80 global land precipitation climatology for the evaluation of general circulation models     

Mike Hulme 《Climate Dynamics》1992,7(2):57-72

Previous evaluations of model precipitation fields have suffered from two weaknesses; they have used only mean observed climatologies which have prevented an explicit evaluation of interannual variability, and they have generally failed to quantify the significance of differences between model and observed fields. To rectify these weaknesses, a global precipitation climatology is required which is designed with model evaluation in mind. This paper describes such a climatology representative of the period 1951–80. The climatology is based on historical gauge-precipitation measurements from over 2500 land-based station time series representing over 28% of the Earth's surface. It is necessarily biased towards terrestrial areas. The climatology (CRU5180) is derived from month-by-month gridbox precipitation estimates at 5° resolution. Although other global precipitation climatologies exist, this is the first one to have used a consistent reference period for each station, and to include the details of interannual variability. Fields of mean seasonal and annual precipitation and mean temporal variability are presented, and the variability of global-mean precipitation over 1951–80 assessed. The resulting mean monthly global precipitation fields are compared briefly with two other observed climatologies used for model evaluation, those prepared by Jaeger and Legates and Willmott. The global and hemispheric means, mean seasonal cycles, and spatial patterns of the three cimatologies are compared. Although based on a smaller set of stations than Legates and Willmott, the CRU5180 precipitation estimates agree closely with their uncorrected climatology.  相似文献   

Reply to P. I. A. Kinnell's comments on ‘the generation and redistribution of overland flow on a massive oxic soil in a eucalypt woodland within the semi-arid tropics of North Australia’, Mike Bonell and John Williams. Hydrological processes, 1, 31–46 (1986)     

Mike Bonell  John Williams 《水文研究》1989,3(1):97-100

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Spatial and temporal variations in bank erosion on sand‐bed streams in the seasonally wet tropics of northern Australia     

M. J. Saynor  Wayne D. Erskine 《地球表面变化过程与地形》2006,31(9):1080-1099

Bank erosion rates and processes across a range of spatial scales are poorly understood in most environments, especially in the seasonally wet tropics of northern Australia where sediment yields are among global minima. A total of 177 erosion pins was installed at 45 sites on four sand‐bed streams (Tributaries North and Central, East Tributary and Ngarradj) in the Ngarradj catchment in the Alligator Rivers Region. Bank erosion was measured for up to 3·5 years (start of 1998/99 wet season to end of 2001/02 wet season) at three spatial scales, namely a discontinuous gully (0·6 km²) that was initiated by erosion of a grass swale between 1975 and 1981, a small continuous channel (2·5 km²) on an alluvial fan that was formed by incision of a formerly discontinuous channel between 1964 and 1978, and three medium‐sized, continuous channels (8·5–43·6 km²) with riparian vegetation. The bank erosion measurements during a period of average to above‐average rainfall established that substantial bank erosion occurred during the wet season on the two smaller channels by rapid lateral migration (Tributary Central) and by erosion of gully sidewalls due to a combination of within‐gully flows and overland flow plunging over the sidewalls (Tributary North). Minor bank erosion also occurred during the dry season by faunal activity, by desiccation and loss of cohesion of the sandy bank sediments and by dry flow processes. The larger channels with riparian vegetation (East Tributary and Ngarradj) did not generate significant amounts of sediment by bank erosion. Deposition (i.e. negative pin values) was locally significant at all scales. Bank profile form and channel planform exert a strong control on erosion rates during the wet season but not during the dry season. Copyright © 2006 Commonwealth Government of Australia.  相似文献   

Automated classification of stellar spectra — II. Two-dimensional classification with neural networks and principal components analysis     

Coryn A. L. Bailer-Jones  Mike Irwin  & Ted von Hippel 《Monthly notices of the Royal Astronomical Society》1998,298(2):361-377

We investigate the application of neural networks to the automation of MK spectral classification. The data set for this project consists of a set of over 5000 optical (3800–5200 Å) spectra obtained from objective prism plates from the Michigan Spectral Survey. These spectra, along with their two-dimensional MK classifications listed in the Michigan Henry Draper Catalogue, were used to develop supervised neural network classifiers. We show that neural networks can give accurate spectral type classifications (σ₆₈= 0.82 subtypes, σ_rms= 1.09 subtypes) across the full range of spectral types present in the data set (B2–M7). We show also that the networks yield correct luminosity classes for over 95 per cent of both dwarfs and giants with a high degree of confidence.   Stellar spectra generally contain a large amount of redundant information. We investigate the application of principal components analysis (PCA) to the optimal compression of spectra. We show that PCA can compress the spectra by a factor of over 30 while retaining essentially all of the useful information in the data set. Furthermore, it is shown that this compression optimally removes noise and can be used to identify unusual spectra.   This paper is a continuation of the work carried out by von Hippel et al. (Paper I).  相似文献