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281.
The paper mentions the first attempts of European savants and scientists in the past centuries to study in a more systematic way the phenomenon named an earthquake. Discussed in this context are the activities developed in the second half of the 19th century by Viennese and other Austro-Hungarian physicists, geologists, geographers and specialists in geomagnetism, geodesy and other geo-disciplines with the aim to initiate regular seismological research in the Monarchy. These efforts resulted in the idea to organize an effective seismic survey which would supply the researchers with continuous earthquake data, first on the macroseismic level, later on the basis of instrumental observations.We speculate upon the reasons which stimulated such a difficult and long-term project at that time and discuss the impact of the new ideas on one particular region of the Monarchy—the territory of Bohemia the seismic activity of which had been described as low or moderate. We link these efforts to the all-European endeavour of the time to promote (up to that time only sporadic) earthquake observations and studies to the rank of systematic seismological research.The paper deals with these activities as they had been accomplished by the end of the 19th century. In Part II, the continuation of the efforts in the first decade of the 20th century will be discussed. The pioneering works reported in both papers quite naturally created a solid fundament for the later development of seismology in former Czechoslovakia and in the present Czech Republic. 相似文献
282.
We closed the preceding part of our paper with the statements that a regular macroseismic service of unprecedented effectivity had been successfully established in the Austrian part of the Monarchy in 1896-1899, and that first continuous instrumental observations had been started at the seismic stations in Ljubljana, Trieste and Kremsmünster in 1897, 1898 and 1899, respectively. In the present part we report how the macroseismic service performed its task from the beginning of the 20th century until the outbreak of World War I, we briefly summarize the beginnings and development of observational seismology in the Hungarian part of the Monarchy, and we inform the reader about the state of European seismometry at the time of establishment of the first stations of the Austro-Hungarian seismographic network.Main topics of the present paper are the history of the development, the principles and properties of the instruments, and the milestones in the interpretation of instrumental observations in both parts of the Monarchy in 1897-1914. The wealth of information extracted from over seventy original papers and books of geoscientists of the time is summarized in the form of two, to a large extent self explaining tables. In Table 1 the altogether seventeen seismic stations gradually established in the Austrian as well as Hungarian parts of the Monarchy in 1897-1914 are ordered chronologically according to the date of initiation of regular measurements at them, and the instruments by which the stations were originally equipped and later successively upgraded are specified. The most important facts about progress in the instrumentation and in the analysis, interpretation and archivation of the observational material are summed up in the last column of Table 1. The principles of the altogether sixteen different types of seismic instruments that were in operation at the stations of the Austro-Hungarian network in the discussed period are explained and their basic technical parameters are specified in Table 2. Those instrumental problems, those moments in the methodology of interpretation of the instrumental observations, and the contributions of those scientists who most decisively influenced the progress of Austro-Hungarian seismology in 1897-1914 are commented in more detail in the text.At the end of the first decade of the 20th century, the instrumentation of the stations of the Austro-Hungarian seismographic network as well as the scientific erudition and publication activities of the station directors and involved geosavants, especially of A. Belar, H. Benndorf, R. Kövesligethy, V. Láska, E. Mazelle, A. and S. Mohorovii and A. Réthly, had reached a standard comparable with that of analogous activities in Italy and Germany. The well developed Austrian macroseismic service gradually disintegrated during World War I. After the war, seismology progressed in the newly constituted states Czechoslovakia, Poland and Yugoslavia in broader, all-European collaboration. 相似文献
283.
Ernst-Jan Buis Marco Beijersbergen Stefan Kraft Alan Owens Francesco Quarati Sytze Brandenburg Reint Ostendorf 《Experimental Astronomy》2005,20(1-3):333-339
Recent developments of cerium-doped lanthanum-halide scintillators like LaBr3:Ce show a remarkable performance in gamma-ray spectroscopy. When high energy resolution in combination with stopping power is required they provide excellent gamma-ray detector candidates for the use in space missions. Moreover, irradiation tests have shown that such detectors are radiation tolerant. In this paper we discuss a possible application of LaBr in nuclear astrophysics missions. We show results on recent proton irradiation tests at KVI in Groningen (NL) and discuss the damage and activation effects after irradiation. A possible implementation for a focal plane detector in a gamma-ray telescope and the expected performance is presented. 相似文献
284.
Axel Schippers Lev N. Neretin Gaute Lavik Falk Pollehne 《Geochimica et cosmochimica acta》2005,69(9):2241-2252
Mn(II) oxidation in the suboxic zone of the water column was studied at four stations in the western Black Sea. We measured Mn(II) oxidation rates using 54Mn tracer and tested the hypothesis of alternative oxidants for Mn(II) other than dissolved oxygen. In anoxic incubation experiments with water from different depths of the chemocline, Mn(II) was not oxidized by nitrite, nitrate, or iodate. In the presence of light, Mn(II) also was not oxidized under anoxic conditions as well. Anaerobic Mn(II) oxidizing microorganisms could not be enriched. In oxic incubation experiments, the addition of alternative oxidants did not significantly increase the Mn(II) oxidation rate. The lack of an anaerobic Mn(II) oxidation in our experiments does not unambiguously prove the absence of anaerobic Mn(II) oxidation in the Black Sea but suggests that dissolved oxygen is the only oxidant for biologically catalyzed Mn(II) oxidation. Lateral intrusions of modified Bosphorus water were shown to be the main mechanism providing dissolved oxygen in the suboxic and the upper anoxic zones and explaining observed Mn(II) oxidation rates. Maximum in situ Mn(II) oxidation rates in the suboxic zone were 1.1 nM Mn(II) per h in the central Black Sea, 25 nM Mn(II) per h on the Romanian continental slope and 60 nM Mn(II) per h on the Anatolian continental slope. These rates correlate with the amount of particulate Mn and the number of Mn-oxide particles and are in agreement with rates measured 13 yr before. Our study highlights the importance of lateral intrusions of oxygen for the ventilation of the suboxic zone and the anoxic interior and for the regulation of different oxidation-reduction processes in the chemocline, including Mn(II) oxidation, which may be significant for other anoxic basins as well. 相似文献
285.
Axel Michaelowa 《Climate Policy》2003,3(1):31
Germany is one of the two OECD countries having achieved substantial greenhouse gas reductions in the last decade. While a part was large reductions in industry after the economic crash in East Germany, a relevant share is due to the huge public infrastructure investments in East Germany. The real success of German climate policy in the past decade is the strong reduction of methane and nitrous oxide which has been almost unnoticed.German climate policy is a good example of how lobbying of interest groups leads to a complex maze of hundreds of measures whose effects are difficult to evaluate. Paradoxically, policies have focused on expensive measures and Germany clearly is a pioneer in the most expensive forms of renewable energy. Concerning cost-effective measures and market instruments, Germany is a laggard. Only slowly, policymakers start to notice this distortion and first, shaky steps towards a more cost-efficient policy are made. Several challenges such as nuclear phase-out and trends in household energy consumption will put pressure on government to embrace the Kyoto Mechanisms and to refocus domestic instruments well before the first commitment period. 相似文献
286.
Transaction costs of the Kyoto Mechanisms 总被引:2,自引:0,他引:2
Transaction costs will reduce the attractiveness of the Kyoto Mechanisms compared to domestic abatement options. Especially the project-based mechanisms Clean Development Mechanism (CDM) and Joint Implementation (JI) are likely to entail considerable costs of baseline development, verification and certification. The Activities Implemented Jointly (AIJ) pilot phase and the Prototype Carbon Fund (PCF) programme give indications about the level of these costs. Under current estimates of world market prices for greenhouse gas emission permits, projects with annual emission reductions of less than 50,000 t CO2 equivalent are unlikely to be viable; for micro projects transaction costs can reach several hundred € per t CO2 equivalent. Thus, the Marrakech Accord rule to have special rules for small scale CDM projects makes sense, even if the thresholds chosen advantage certain project types; projects below 1000 t CO2 equivalent per year should get further exemptions. An alternative solution with no risk for the environmental credibility of the projects would be to subsidise baseline setting and charge lower, subsidised fees for small projects for the different steps of the CDM/second track JI project cycle. 相似文献
287.
The reductive amination of low‐molecular‐weight saccharides, uronic acids, and amino sugars, followed by a separation of the derivates by means of ion‐pair chromatography or RP‐HPLC, offers an interesting alternative to HPAEC‐PAD for the environmental analysis of these compounds. Under this aspect various potential amination reagents, i.e., p‐amino‐benzoic acid (p‐AMBA), p‐AMBA propyl ester, 1‐aminopyrene, 2‐(2‐aminophenyl)indole, and 4‐aminoazobenzene, were tested with regard to the formation of derivates and to the chromatographic properties of the formed derivates. p‐AMBA, p‐AMBA propyl ester and 4‐aminoazobenzene proved to be especially suited, because they facilitate the amination of all carbohydrate reference components together with a complete separation and sensible detection (detection limits < 0.5 mg/L) of the derivates. Mainly the following elution sequence was ascertained: amino sugars (hexosamines) / disaccharide(s) / monosaccharides (hexoses) / hexuronic acid(s) / N‐acetyl‐D‐glucosamine. Detection limits down to 0.1 μmol/L were realized using p‐AMBA as reagent, facilitating the determination of the target compounds in landfill leachates and lysimeter percolates. Applying the p‐AMBA propyl ester for derivatization, chromatographic interferences with weakly retained derivates and the coelution of the reagent with its galactosamine derivate can be avoided, since the ester elutes after its derivates unlike p‐AMBA itself. 相似文献
288.
Axel Müller Paul Lennox Robert Trzebski 《Contributions to Mineralogy and Petrology》2002,143(4):510-524
Trace elements (Al, K, Ti, Fe), growth and deformation pattern in quartz of the multiple deformed Carcoar, Barry and Sunset Hills granites were investigated by electron micro probe and cathodoluminescence. Zoned quartz phenocrysts with high Ti concentrations (>70 ppm) that show blue cathodoluminescence originated from the early stage of magma crystallisation. Multiple deformation of quartz causes the redistribution of Al and K in the quartz lattice, which results in the accumulation of these elements in submicroscopic inclusions (<0.5 µm) of muscovite-like composition. In contrast, structural Ti in quartz is mostly kept in the lattice. Common halos of defect-poor, secondary quartz around fluid inclusions result from re-equilibration of fluid inclusions because of differences between fluid pressure and lithostatic pressure, e.g. during uplift (isothermal decompression) and/or !/#-transition of quartz. During healing, defect-poor secondary quartz grows at the cost of the host quartz and releases or replaces defect centres. The results of micro-structural investigations combined with Al-in-hornblende thermobarometry allow the reconstruction of regional processes. Carcoar and Barry granodiorites and Sunset Hills granite were intruded in the Late Ordovician-Early Silurian at depths of 4-8.6 and 10-12 km, respectively. In contrast to the continuous crystallisation of the granodiorite magmas, the magma of the Sunset Hills granite ascended in a stepwise fashion, causing multiple quartz nucleation. The two granodiorites were multiple, post-magmatically deformed, first, during Early Devonian under more brittle conditions at temperatures of 350-400 °C, whereas the Sunset Hills granite experienced more ductile deformation at temperatures of around 550 °C. 相似文献
289.
Long-duration deformation experiments at room temperature have shown that crystalline rocks with low porosities, such as granites, diorites, gneisses and metabasites, swell when saturated with water and shrink when dried out. The effect is reversible and reproducible. The swelling cannot be completely hindered by confining pressures up to 15 MPa. The volume strain (from the dry to the saturated state) is of the order of a tenth of the porosity. The volume strain is decreased in brine with increasing molarity and becomes much smaller by saturation with heptane. Swelling and shrinking can also be observed with sorption and desorption of water, that is a change in the relative humidity of the air. It is proposed that the swelling effect is due to surface forces, that is van der Waals attraction and electrostatic double-layer and solvation repulsion. The pore pressure causing the swelling was estimated to be of the order of 15 MPa. This indicates the presence of very flat pores with distances between the surfaces of about 1 nm. The surface forces probably also play an important role in determining the seismic properties of the rocks at low confining pressures. 相似文献
290.
Tectono‐sedimentary evolution of the northern Iranian Plateau: insights from middle–late Miocene foreland‐basin deposits
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Paolo Ballato Francesca Cifelli Ghasem Heidarzadeh Mohammad R. Ghassemi Andrew D. Wickert Jamshid Hassanzadeh Guillaume Dupont‐Nivet Philipp Balling Masafumi Sudo Gerold Zeilinger Axel K. Schmitt Massimo Mattei Manfred R. Strecker 《Basin Research》2017,29(4):417-446
Sedimentary basins in the interior of orogenic plateaus can provide unique insights into the early history of plateau evolution and related geodynamic processes. The northern sectors of the Iranian Plateau of the Arabia–Eurasia collision zone offer the unique possibility to study middle–late Miocene terrestrial clastic and volcaniclastic sediments that allow assessing the nascent stages of collisional plateau formation. In particular, these sedimentary archives allow investigating several debated and poorly understood issues associated with the long‐term evolution of the Iranian Plateau, including the regional spatio‐temporal characteristics of sedimentation and deformation and the mechanisms of plateau growth. We document that middle–late Miocene crustal shortening and thickening processes led to the growth of a basement‐cored range (Takab Range Complex) in the interior of the plateau. This triggered the development of a foreland‐basin (Great Pari Basin) to the east between 16.5 and 10.7 Ma. By 10.7 Ma, a fast progradation of conglomerates over the foreland strata occurred, most likely during a decrease in flexural subsidence triggered by rock uplift along an intraforeland basement‐cored range (Mahneshan Range Complex). This was in turn followed by the final incorporation of the foreland deposits into the orogenic system and ensuing compartmentalization of the formerly contiguous foreland into several intermontane basins. Overall, our data suggest that shortening and thickening processes led to the outward and vertical growth of the northern sectors of the Iranian Plateau starting from the middle Miocene. This implies that mantle‐flow processes may have had a limited contribution toward building the Iranian Plateau in NW Iran. 相似文献