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排序方式: 共有134条查询结果,搜索用时 62 毫秒
41.
Brigitte Wolkinger Andrea Damm Stefan Schleicher Andreas Tuerk Wolf Grossman 《Climate Policy》2013,13(6):667-689
Having agreed upon a binding emissions reduction path by 2020, the EU plays a leading role in international climate policy. The EU currently pursues a dual approach through an Emissions Trading Scheme (ETS) at the EU level and also via national targets in sectors not covered by the ETS. The latter include the buildings sector, transportation, agriculture, and waste. Emissions from these sectors are mainly subject to policies at provincial and local levels. A method is presented for elaborating and implementing a long-term climate policy process up to 2030 for the regional (provincial) level. Building on regional GHG inventory data, a set of indicators for each sector is developed in order to arrive at a target path consistent with the deduced regional GHG reduction requirement. Policy measures and their implementation are then settled subsequent to this process. Quantitative regional targets are found to be a prerequisite for the formation of regional climate policy as they increase participant responsibility and commitment. A five-step process of stakeholder participation ensures effective implementation of regional climate action plans. Insights from an exemplary European region are drawn upon, and policy issues are discussed in both quantitative and institutional terms. 相似文献
42.
Qi‐Chao Yang Klaus Peter Jochum Brigitte Stoll Ulrike Weis Dmitry Kuzmin Michael Wiedenbeck Heike Traub Meinrat O. Andreae 《Geostandards and Geoanalytical Research》2012,36(3):301-313
To test whether the silicate reference glasses BAM‐S005‐A and BAM‐S005‐B from BAM (The Federal Institute for Materials Research and Testing, Germany) are suitable materials for microanalysis, we investigated the homogeneity of these reference glasses using the microanalytical techniques EPMA, LA‐ICP‐MS and SIMS. Our study indicated that all major and most trace elements are homogeneously distributed at micrometre sampling scale in both types of glass. However, some trace elements (e.g., Cs, Cl, Cr, Mo and Ni) seem to be inhomogeneously distributed. We also determined the composition of BAM‐S005‐A and BAM‐S005‐B. The EPMA data of major elements confirmed the information values specified by the certificate. With the exception of Sr, Ba, Ce and Pb, our trace element data by LA‐ICP‐MS were also in agreement with the certified values within the stated uncertainty limits. The reasons for the discrepancy in these four elements are still unclear. In addition, we report new data for twenty‐two further trace elements, for which the concentrations were not certified. Based on our investigation, we suggest that both of these materials are suitable for many microanalytical applications. 相似文献
43.
Brigitte Gavio Shelly Palmer-Cantillo J. Ernesto Mancera 《Marine pollution bulletin》2010,60(7):1018-1030
To understand the coastal water quality of San Andrès Island, and provide tools for the management of its marine resources, we present the historical analysis of the island monitoring, which includes ammonia, nitrites, nitrate, phosphates, fecal and total coliforms. The anthropogenic pressure on the coastal system is heavy, with water nutrification, posing at risk seagrass and coral ecosystems. During dry season, biologically available nitrogen is 3-9 times higher than the maximum recommended for coral reefs, while during wet season values are 2-6.4 times the maximum. Biologically available phosphorous is also high, 1-8 times the maximum during dry season, 2-13 times during wet season. In some sites the concentration of pathogenic bacteria is above the limits set by law for primary and secondary contact. It is urgent to improve the management of sewage discharge, the main polluting source of San Andres coastal waters. 相似文献
44.
On the repeatability and consistency of three-component ambient vibration array measurements 总被引:1,自引:0,他引:1
Brigitte Endrun Matthias Ohrnberger Alexandros Savvaidis 《Bulletin of Earthquake Engineering》2010,8(3):535-570
Ambient vibration measurements with small, temporary arrays that produce estimates of surface wave dispersion have become
increasingly popular as a low-cost, non-invasive tool for site characterisation. An important requirement for these measurements
to be meaningful, however, is the temporal consistency and repeatability of the resulting dispersion and spatial autocorrelation
curve estimates. Data acquired within several European research projects (NERIES task JRA4, SESAME, and other multinational
experiments) offer the chance to investigate the variability of the derived data products. The dataset analysed here consists
of repeated array measurements, with several years of time elapsed between them. The measurements were conducted by different
groups in different seasons, using different instrumentations and array layouts, at six sites in Greece and Italy. Ambient
vibration amplitude spectra and locations of dominant sources vary between the two measurements at each location. Still, analysis
indicates that this does not influence the derived dispersion information, which is stable in time and neither influenced
by the instrumentation nor the analyst. The frequency range over which the dispersion curves and spatial autocorrelation curves
can be reliably estimated depends on the array dimensions (minimum and maximum aperture) used in the specific deployment,
though, and may accordingly vary between the repeated experiments. The relative contribution of Rayleigh and Love waves to
the wavefield can likewise change between repeated measurements. The observed relative contribution of Rayleigh waves is generally
at or below 50%, with especially low values for the rural sites. Besides, the visibility of higher modes depends on the noise
wavefield conditions. The similarity of the dispersion and autocorrelation curves measured at each site indicates that the
curves are stable, mainly determined by the sub-surface structure, and can thus be used to derive velocity information with
depth. Differences between velocity models for the same site derived from independently determined dispersion and autocorrelation
curves—as observed in other studies—are consequently not adequately explained by uncertainties in the measurement part. 相似文献
45.
Klaus Peter Jochum Ulrike Weis Brigitte Stoll Dmitry Kuzmin Qichao Yang Ingrid Raczek Dorrit E. Jacob Andreas Stracke Karin Birbaum Daniel A. Frick Detlef Günther Jacinta Enzweiler 《Geostandards and Geoanalytical Research》2011,35(4):397-429
We present new reference values for the NIST SRM 610–617 glasses following ISO guidelines and the International Association of Geoanalysts’ protocol. Uncertainties at the 95% confidence level (CL) have been determined for bulk‐ and micro‐analytical purposes. In contrast to former compilation procedures, this approach delivers data that consider present‐day requirements of data quality. New analytical data and the nearly complete data set of the GeoReM database were used for this study. Data quality was checked by the application of the Horwitz function and by a careful investigation of analytical procedures. We have determined quantitatively possible element inhomogeneities using different test portion masses of 1, 0.1 and 0.02 μg. Although avoiding the rim region of the glass wafers, we found moderate inhomogeneities of several chalcophile/siderophile elements and gross inhomogeneities of Ni, Se, Pd and Pt at small test portion masses. The extent of inhomogeneity was included in the determination of uncertainties. While the new reference values agree with the NIST certified values with the one exception of Mn in SRM 610, they typically differ by as much as 10% from the Pearce et al. (1997) values in current use. In a few cases (P, S, Cl, Ta, Re) the discrepancies are even higher. 相似文献
46.
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48.
Shitou Wu Gerhard Wrner Klaus Peter Jochum Brigitte Stoll Klaus Simon Andreas Kronz 《Geostandards and Geoanalytical Research》2019,43(4):567-584
Three synthetic reference glasses were prepared by directly fusing and stirring 3.8 kg of high‐purity oxide powders to provide reference materials for microanalytical work. These glasses have andesitic major compositions and are doped with fifty‐four trace elements in nearly identical abundance (500, 50, 5 µg g?1) using oxide powders or element solutions, and are named ARM‐1, 2 and 3, respectively. We further document that sector‐field (SF) ICP‐MS (Element 2 or Element XR) is capable of sweeping seventy‐seven isotopes (from 7Li to 238U, a total of sixty‐eight elements) in 1 s and, thus, is able to quantify up to sixty‐eight elements by laser sampling. Micro‐ and bulk analyses indicate that the glasses are homogeneous with respect to major and trace elements. This paper provides preliminary data for the ARM glasses using a variety of analytical techniques (EPMA, XRF, ICP‐OES, ICP‐MS, LA‐Q‐ICP‐MS and LA‐SF‐ICP‐MS) performed in ten laboratories. Discrepancies in the data of V, Cr, Ni and Tl exist, mainly caused by analytical limitations. Preliminary reference and information values for fifty‐six elements were calculated with uncertainties [2 relative standard error (RSE)] estimated in the range of 1–20%. 相似文献
49.
Detectability of gravitational waves emitted by newly born, hot, rapidly rotating neutron stars as they spin down due to the r-mode instability is discussed. It is shown that differential rotation induced by r-modes plays a fundamental role in the evolution of the mode’s instability, making it more difficult to detect these gravitational waves. 相似文献
50.
Brigitte Schmieder 《Solar physics》1976,47(2):435-460
Using a 32 minutes sequence of observation, brightness and velocity fluctuations in the wings of the Mgi line at 5172.7 Å and Fe ii line at 5197.578 Å are analysed. The analysis of phase shifts and amplitude ratios leads to the following conclusions:
(1) | In the frequency range from (400s)–1 to (130s)–1, we find the existence of three modes of waves: internal gravity, evanescent and propagating acoustic waves which appear with increasing frequency. A satisfactory agreement for velocity between observations and theory in the range of horizontal wavelengths \s>5000km with a theoretically local relaxation time –180s-40s is obtained. The calculation of intensity fluctuations shows that the Mgi line is sensitive to temperature and density fluctuations while the Fe ii line is only sensitive to temperature perturbation. For the best fit with the same value of –1 to both lines (i.e., Fe ii and Mg i) it is found necessary that the density effect should be taken into account for the Mg i intensity fluctuations. The relaxation time deduced from observed intensity fluctuations seems to decrease with the period of oscillation. This suggests the presence of a dissipation process. 相似文献 |