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41.
Zhang Jin-Zhang Zhang Dong-Ming Huang Hong-Wei Phoon Kok Kwang Tang Chong Li Gang 《Acta Geotechnica》2022,17(4):1129-1145
Acta Geotechnica - The scale of fluctuation (SOF) is the critical parameter to describe the soil spatial variability, which significantly influences the embedded geostructures. Due to the limited... 相似文献
42.
Ha-Gyu Jeong Joong-Bae Ahn Joonlee Lee Kyo-Moon Shim Myung-Pyo Jung 《Theoretical and Applied Climatology》2020,139(3):923-934
Improved daily precipitation estimations were attempted using the parameter-elevation regressions on a parameter-elevation regression on independent slopes model (PRISM) with inverse-distance weighting (IDW) and a precipitation-masking algorithm for precipitation areas. The PRISM (PRISM_ORG) suffers two overestimation problems when the daily precipitation is estimated: overestimation of the precipitation intensity in mountainous regions and overestimation of the local precipitation areas. In order to solve the problem of overestimating the precipitation intensity, we used the IDW technique that employs the same input stations as those used in the PRISM regression (PRISM_IDW). A precipitation-masking algorithm that selectively masks the precipitation estimation grid points was additionally applied to the PRISM_IDW results (PRISM_MSK). For 6 months from March to August 2012, daily precipitation data were produced in a horizontal resolution of 1 km based on the above two experiments and PRISM_ORG. Afterwards, each experiment was evaluated for improvements. The monthly root mean squared errors (RMSEs) of PRISM_IDW and PRISM_MSK were reduced by 0.83 mm/day and 0.86 mm/day, respectively, compared to PRISM_ORG. 相似文献
43.
Ecosystem responses to climate change in a large on-river reservoir, Lake Paldang, Korea 总被引:3,自引:0,他引:3
Hae-Kyung Park Kang-Hyun Cho Doo Hee Won Jangho Lee Dong-Soo Kong Dong-Il Jung 《Climatic change》2013,120(1-2):477-489
The impact of climate change on a large river reservoir ecosystem was investigated. Long-term meteorological data showed that recent climate change, including warmer winters, increased precipitation intensity and extended dry periods, may have influenced the basin of Lake Paldang, the most downstream reservoir of a series of on-river reservoirs. Extreme hydrologic events and climate warming, acting independently and in combination, appear to be related to changes in the Lake Paldang ecosystem. A significant increase in chlorophyll a concentrations in early spring corresponded to the timing of ice break-up. An increase in winter temperatures, which resulted in a shorter time period of ice-cover and earlier ice break-up, appears to have stimulated phytoplankton growth in winter and early spring. Repeated intensive and extended influxes of turbid water, associated with more frequent extreme rainfall events, have increased concentration of suspended solids and may have influenced the biotic community structure of Lake Paldang. In the mid-2000s, the area vegetated by submerged hydrophytes, the abundance and biomass of the phylum Mollusca, as well as the abundance of fish from the subfamily Acheilognathinae, which spawn in the body of bivalve molluscs, was all smaller than in the late 1980s and early 1990s. Together, these results suggest that climate change may have contributed directly and indirectly to changes in each trophic level of the Lake Paldang ecosystem. 相似文献
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We previously described the genomic structure of the cytochrome P450 1A (CYP1A) gene from the hermaphroditic fish Rivulus marmoratus [Kim, I.-C., Kim, Y.J., Yoon, Y.-D, Kawamura, S., Lee, Y.-S., Lee, J.-S., 2004a. Cloning of cytochrome P450 1A (CYP1A) genes from the hermaphroditic fish Rivulus marmoratus and the Japanese medaka Oryzias latipes. Mar. Environ. Res. 58, 125–129]. To further characterize R. marmoratus CYP1A, we cloned the cDNA sequence of a CYP1A gene from this species and also expressed its recombinant protein in an E. coli system. We exposed R. marmoratus to 4-nonylphenol, and found a small induction of CYP1A mRNA in the treated animals. In this paper, we discuss the characteristics of R. marmoratus CYP1A gene as well as its potential use in a biomonitoring assay. 相似文献
47.
Using density functional simulations, within the generalized gradient approximation and projector-augmented wave method, we study structures and energetics of CaSiO3 perovskite in the pressure range of the Earths lower mantle (0–150 GPa). At zero Kelvin temperature the cubic
CaSiO3 perovskite structure is unstable in the whole pressure range, at low pressures the orthorhombic (Pnam) structure is preferred. At 14.2 GPa there is a phase transition to the tetragonal (I4/mcm) phase. The CaIrO3-type structure is not stable for CaSiO3. Our results also rule out the possibility of decomposition into oxides.
相似文献
Daniel Y. JungEmail: Phone: +41-44-6323744Fax: +41-44-6321133 |
48.
The common practice of freezing sediment cores for later chemical investigation was shown to be inappropriate for samples containing selenium. Pore waters from frozen estuarine sediment cores contained up to eighty times the selenium content of those extracted from chilled but unfrozen cores. Experiments suggested that the increase in selenium concentrations resulted from rupturing the cells of selenium-accumulating bacteria present in the samples. 相似文献
49.
Kocatepe Ayberk Ulak Mehmet Baran Kakareko Grzegorz Ozguven Eren Erman Jung Sungmoon Arghandeh Reza 《Natural Hazards》2019,95(3):615-635
Natural Hazards - Roadway closures magnify the adverse effects of disasters on people since any type of such disruption increases the emergency response travel time (ERTT), which is of central... 相似文献
50.
Zusammenfassung Es wird eine quantitative Ableitung der Coriolisbeschleunigung auf einer rotierenden Kugel gegeben. Die Rechnungen setzen etwa die Kenntnisse eines Abiturienten voraus und sind so geführt, daß die Coriolisbeschleunigung rein in Erscheinung tritt. Erdabplattung und horizontale Führungskräfte, die mit dem Wesen der Corioliskraft nichts zu tun haben, kommen in der Ableitung nicht vor.
An introductory mathematical treatment of the Coriolis force
Summary A quantitative derivation of the Coriolis acceleration on a rotating sphere is given which is considered adequate for students who have passed the final examination of a German High School. Computations are presented in a way that demonstrates the Coriolis acceleration without distracting side issues. The earth's oblateness and the horizontal guiding forces not essentially relating to the Coriolis force are not taken into account in this derivation.
Une introduction dans l'étude de la force de Coriolis
Résumé On donne une dérivation quantitative de l'accélération de Coriolis sur un globe rotatoire. Les calculations nécessaires sont adaptées au savoir d'un bachelier et sont présentées d'une manière que l'accélération de Coriolis est démontrée sans digressions. L'aplatissement de la terre aux pôles et les forces guidantes horizontales qui n'ont pas de rapport essentiel à la nature de l'accélération de Coriolis sont laissés de côté dans cette déduction.相似文献