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Kumar M. Dinesh Tandon Shubham Bassi Nitin Mohanty Pradipta Kumar Kumar Saurabh Mohandas Manish 《Natural Hazards》2022,110(3):2035-2057
Natural Hazards - Many coastal cities in developing countries are at the risk of flooding due to a progressive increase in the built-up areas and poor management of storm water. The flooding... 相似文献
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Summary Mechanically stirred actinometric solutions of uranyl oxalate, sensitive to radiation below 4300 Å, are found to respond consistently to conditions of solar radiation which are met in Italy during summer, at elevations between 0–3500 metres. The instrumentation developed permits to monitor the course of radiation-dependent chemical reactions in solution, under sunlight. 相似文献
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Alberto C. Montefinale Gianna L. Petriconi Henry M. Papee 《Pure and Applied Geophysics》1970,83(1):182-200
Summary A systematic cloud-seeding experiment was conducted in the Prenestine Hills, east of Rome, during the period of time Jan. 1966 – June 1968. The objective was to determine whether the use of monodisperse, electron-emitting giant condensation nuclei, and of giant Al2S3 ice-forming nuclei, both recently developed in our laboratories, could increase the precipitation over an area circumjacent to the site of aerosol dispersion. The method of evaluation involved comparisons of precipitation fallen during the week which followed the aerosolization of about 15 kg. of particulate matter, to the precipitation collected during the fortnight aftet that period. The results show that despite a relatively small amount of nuclei used per seeding operation, and notwithstanding an apparently handicapped design of data evaluation, the normalized and cumulated ratios of precipitation events, associated with those periods of time, indicate significant increases during summer and autumn, and significant decreases during winter season, over the area considered. 相似文献
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G. N. Zastenker E. Salerno F. Buehler P. Bochsler M. Bassi Yu. N. Agafonov N. A. Eismont V. V. Khrapchenkov H. Busemann 《Astrophysics》2002,45(2):131-142
One of the important problems in astrophysics is the determination of the abundances of the helium isotopes 3He and 4He in various regions of the universe, since those abundances can provide evidence of the intensities of various possible processes of the production and decay of light elements and can thereby reflect their history. In this paper we describe the procedure and results of the first determination by a direct method of the abundances of helium isotopes in the local interstellar medium surrounding the solar system. The experiment was carried out on the piloted MIR station by the prolonged exposure in open space of specimens of metallic foil with their subsequent return to earth and detailed laboratory mass-spectrometric analysis. As a result, we were able to obtain estimates of the 4He density (about 7.5·10-3 cm-3) and the 3He/4He isotopic ratio (about 1.7·10-4) for the local interst ellar medium. 相似文献
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Md. Aftabuzzaman Kazuki Yomogida Shota Suzuki Hideko Takayanagi Akimasa Ishigaki Shiki Machida Yoshihiro Asahara Koshi Yamamoto Naoto Hirano Shin-Ichi Sano Shun Chiyonobu Davide Bassi Yasufumi Iryu 《Island Arc》2021,30(1):e12400
Sedimentological, geochemical, and chronological analyses were carried out on 18 carbonate rock samples collected at depths of 938, 1085, and 3354 m on the western slope of Minamitorishima (Marcus Island), which is located near the western margin of the Pacific Plate. Four groups of carbonate rocks were distinguished: a mollusk-rich limestone, a coral-rich dolomite, a foraminiferal-nannofossil packstone, and a phosphatized mudstone/wackestone. The mollusk-rich limestone is characterized by the dominance of bivalves (including rudists) and gastropod shells. Strontium isotope ratios (87Sr/86Sr) and Mesorbitolina ex gr. texana (a large benthic foraminifer) indicate that the shallow-water carbonates were deposited during the late Aptian–early Albian (ca. 123–111 Ma). The coral-rich dolomite is characterized by abundant scleractinian corals and nongeniculate coralline algae associated with encrusting acervulinid foraminifers. The biotic composition is similar to that of the Oligocene–Pleistocene carbonates reported from other seamounts in the northwestern Pacific. Geochemical data show that the coral-rich carbonates were dolomitized at 9.5–6.8 Ma (Tortonian–Messinian) and that normal seawater was the most likely parent fluid. The foraminiferal-nannofossil packstone is a semi-consolidated foraminiferal-nannofossil ooze and was deposited during the Pleistocene (0.99–0.45 Ma). The phosphatized mudstone/wackestone is marked by the absence of macrofossils and the presence of traces of planktic foraminifers. Although its depositional age is not constrained, the Sr isotope ratios indicate that the phosphatization occurred at 33.2–28.9 Ma. After the deposition of the Cretaceous shallow-water carbonates, including the mollusk-rich limestone, Minamitorishima was drowned and its top was covered with a pelagic cap, represented by the mudstone/wackestone. The late Eocene–early Oligocene volcanism (40.2–33.2 Ma) caused episodic uplift and returned the top of Minamitorishima to a shallow-water environment. After the early Oligocene phosphatization of the pelagic cap, coral reefs flourished on the top of this island. The reef limestone was dolomitized during the Tortonian–Messinian. 相似文献