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A method was developed for the determination of organic halogens in water samples with the aim of minimizing matrix effects and simplifying the sample preparation technique commonly used. The method is based on the adsorption of organic halogens in modified hydrophilic divinylbenzene polymer columns and their elution with methanol. The adsorbent used enables rapid adsorption and desorption due to comparatively high operating flow rates and minimized solvent amounts. Furthermore, no additional reconcentration steps are needed. The methanol extract obtained is combusted with a standard EOX (extractable organic halogen) analyzer and the concentration of organically bound halogens is determined by microcoulometric analysis. The matrix effects are considerably reduced compared to the standard procedure (EN 1485) commonly used. A detection limit of 13 μg/L was established. 相似文献
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Manfred Gottwald Thomas Fritz Helko Breit Birgit Schättler Alan Harris 《Meteoritics & planetary science》2017,52(7):1412-1427
With the TanDEM‐X digital elevation model (DEM), the terrestrial solid surface is globally mapped with unprecedented accuracy. TanDEM‐X is a German X‐band radar mission whose two identical satellites have been operated in single‐pass interferometer configuration over several years. The acquired data are processed to yield a global DEM with 12 m independent posting and relative vertical accuracies of better than 2 m and 4 m in moderate and mountainous terrain, respectively. This DEM provides new opportunities for space‐borne remote‐sensing studies of the entire sample of terrestrial impact craters. In addition, it represents an interesting repository to aid in the search for new impact crater candidates. We have used the TanDEM‐X DEM to investigate the current set of confirmed impact structures. For a subsample of the craters, including small, midsized, and large structures, we compared the results with those from other DEMs. This quantitative analysis demonstrates the excellent quality of the TanDEM‐X elevation data. Our findings help to estimate what can be gained by using the TanDEM‐X DEM in impact crater studies. They may also be beneficial in identifying the regions and morphologies where the search for currently unknown impact structures might be most promising. 相似文献
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Nils Reiche Tanja Westerkamp Steffen Lau Helko Borsdorf Peter Dietrich Claudia Schütze 《Environmental Earth Sciences》2014,72(5):1435-1441
Today, ground-based optical remote sensing (ORS) has become an intensively used method for quantifying pollutant or greenhouse gas emissions from point or area sources, and for the validation of airborne or satellite remote sensing data. In this study, we present the results of a release experiment using acetylene (C2H2) as a tracer gas, where three ORS techniques were simultaneously tested for two main purposes: (1) the detection of emission sources and (2) the quantification of release rates. Therefore, passive and active open-path Fourier transform infrared spectroscopy (OP-FTIR) and open-path tunable diode laser absorption spectroscopy (TDLAS) were applied and evaluated. The concentration results of the active ORS methods are compared to those estimated by a Lagrangian stochastic atmospheric dispersion model. Our results reveal that passive OP-FTIR is a valuable tool for the rapid detection and imaging of emission sources and the spatial tracer gas distribution; while with active OP-FTIR and TDLAS, C2H2 concentrations in the sub-ppm range could be quantified that correlated well with the concentration data obtained by our modeling approach. 相似文献
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Axel. Dr. phil. habil. Borsdorf 《GeoJournal》1987,15(1):57-62
Cities as crystalisations of civilizations represent symbolic impact in their layout and architecture. Built environment in
this sense has an symbolic impact. Intending to understand a civilization it can be helpful to look at these symbols.
This article tries to demonstrate the changing symbols in different historic periods of Latin America. Symbols were to be
found in the urban morphology of even the precolumbian cities. They changed within the colonial era, and again during the
different influences of French, British or North American domination. Today there can be noticed a decline of the traditional
symbolic elements of towns. On the other hand there are certain symptoms of a crisis of self-identity of the Latin Americans.
So even the diverse ideas how to define a new image are to be seen in the built environment of main cities of various states.
shortened version of a presentation to the Meeting of the Association of Pacific Coast Geographers at Eugene, Oregon, September
12, 1986
I wish to thank my friend William S. Preston, Department of Geography, Calif. Polytechnic State Univ. San Luis Obispo, for
his patience helping me to translate this article. It was a pleasure to have a competent translater and partner of discussion. 相似文献
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Axel Borsdorf 《GeoJournal》1991,2(1):47-60
The population of Latin America will be increasing by 130 % between 1970 and the year 2000. Due to excessive rural exodus the urban population grows almost twice as fast as the rural does. The urbanization of the subcontinent must be regarded as being the dominant spatial process in Latin America. It results in fundamental changes of the structure and the way of life of the population as well as in the size and character of the settlements.Three case studies (Popayán/Colombia, Sucre/Bolivia and Santiago/Chile) show that a process of westernization can be observed within the analogous to their size, in the course of which the compact structure of the colonial town pattern is succeeded by a sectorially or cellularly arranged cityorganism.From today's point of view a definite judgement on urbanization as a relevant phenomenon of development cannot yet be made. It can be stated, however, that the southern countries of Latin America which have been urbanized the most show distinct signs of a social and economic take off. 相似文献
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Borsdorf A 《GeoJournal》1978,2(1):47-60
The population of Latin America will be increasing by 130 % between 1970 and the year 2000. Due to excessive rural exodus the urban population grows almost twice as fast as the rural does. The urbanization of the subcontinent must be regarded as being the dominant spatial process in Latin America. It results in fundamental changes of the structure and the way of life of the population as well as in the size and character of the settlements. Three case studies (Popayán/Colombia, Sucre/Bolivia and Santiago/Chile) show that a process of westernization can be observed within the analogous to their size, in the course of which the compact structure of the colonial town pattern is succeeded by a sectorially or cellularly arranged cityorganism. From today's point of view a definite judgement on urbanization as a relevant phenomenon of development cannot yet be made. It can be stated, however, that the southern countries of Latin America which have been urbanized the most show distinct signs of a social and economic “take off”. 相似文献
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In the summer of 2010/2011 Chile suffered the third most severe energy and water supply crisis in only one decade.This may be surprising as the Andes which accompany the country along 4,200 km are a water tower and could provide more electricity and water than needed.On top of that,it has to be mentioned that Chile also counts with sunny and windy climates and with excellent geothermal energy resources and thus has a huge potential as far as renewable energies are concerned.After analyzing the existing natural conditions,the infrastructure and the present challenges of climate change,it has to be asked in which way Chile can make use of this potential in the near future,considering the legal and political situation and the technological opportunities.It seems that the resources are still hidden in the Andes,and only the key is missing to realize the country’s natural potential.This research has been based on the analysis of existing literature,media,quantitative data from government institutions and other antecedents obtained by the authors in field work done in the South of Chile in 2010.The added value of this compilation lies in the comprehensive perspective,linking the knowledge of climatologists,hydrologists,mountain researchers and energy experts in order to support a sustainable energy and water supply for the future in Chile.From this present research,it can be concluded that Chile necessarilyhas to adopt new energy-related strategies,particularly those aimed at diminishing the strong dependence on traditional sources of energy and establishing new techniques and technologies for generating electricity and utilizing the vast potential that the country is ready to offer,such as that provided by the Andes along 4,200 kilometers. 相似文献
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