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81.
Water Resources - For the first time, data are given on cyanobacterial toxins entering tap water, supplied to the population of some cities in Yaroslavl oblast. The detection of microcystins with... 相似文献
82.
Water Resources - The results of long-term studies of a group of aufeis-forming Buluus groundwater sources are given. A stow, which has been formed by the spring, contains the drainage area of the... 相似文献
83.
Water Resources - The article presents the results of summer dry-season areal surveys of subsoil water chemistry in the drainage basin of the Ivankovo Reservoir in the Volga segment from Tver City... 相似文献
84.
Constantinos C. Repapis Petros P. Mimoglou Vicky V. Dimakopoulou Ioannis N. Psycharis Ioannis M. Taflampas 《地震工程与结构动力学》2020,49(5):479-497
The special interest produced by near-field directivity records and their effect on structural response has given a new significance in the velocity time history, its pulse-like content, and relevant parameters and indices. Recent research has shown that directivity pulses inherent in these records govern the linear and the nonlinear response of a wide range of structures. Based on this observation, it is suggested in this paper that a truncated ground motion, limited to the duration of the predominant velocity pulse, can be efficiently used to predict the structural response, instead of the base motion with the total duration, reducing significantly the required runtimes. The proposed methodology is verified for a series of medium to high rise reinforced concrete buildings, for which nonlinear time-history analyses are performed for a vast suite of pulse-like near-field records applied as base excitations with their total duration and the proposed truncated one. Comparison of the results for the response displacements and forces shows very good agreement, permitting the acceptance of the pulse duration as the efficient strong motion time interval of the original record, which determines the response and, thus, it can be used for nonlinear structural analyses. 相似文献
85.
Charles C. Rhoades Timothy S. Fegel Timothy P. Covino Kathleen A. Dwire Kelly Elder 《水文研究》2021,35(3):e14089
Springs are the point of origin for most headwater streams and are important regulators of their chemical composition. We analysed solute concentrations of water emerging from 57 springs within the 3 km2 Fool Creek catchment at the Fraser Experimental Forest and considered sources of spatial variation among them and their influence on the chemical composition of downstream water. On average, calcium and acid neutralizing capacity (bicarbonate-ANC) comprised 50 and 90% of the cation and anion charge respectively, in both spring and stream water. Variation in inorganic chemical composition among springs reflected distinct groundwater sources and catchment geology. Springs emerging through glacial deposits in the upper portion of the catchment were the most dilute and similar to snowmelt, whereas lower elevation springs were more concentrated in cations and ANC. Water emerging from a handful of springs in a geologically faulted portion of the catchment were more concentrated than all others and had a predominant effect on downstream ion concentrations. Chemical similarity indicated that these springs were linked along surface and subsurface flowpaths. This survey shows that springwater chemistry is influenced at nested spatial scales including broad geologic conditions, elevational and spatial attributes and isolated local features. Our results highlight the role of overlapping factors on solute export from headwater catchments. 相似文献
86.
Slyuta E. N. Vysochkin V. V. Ivanov V. V. Makovchuk V. Yu. Nazarov A. I. Pogonin V. I. Roskina E. A. Safronov V. V. Tatsiy L. P. 《Solar System Research》2021,55(5):437-445
Solar System Research - The ionization-type cosmic dust detector METEOR-L is being developed for the lunar orbiter Luna-26 and is designed to study the distribution of meteoric bodies in space by... 相似文献
87.
Astronomy Letters - The sensitivity of future far-infrared telescopes, such as Millimetron, will be limited by the confusion noise produced by distant galaxies. We have constructed a model of the... 相似文献
88.
Bondur V. G. Vorobyev V. E. Murynin A. B. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(9):887-897
Izvestiya, Atmospheric and Oceanic Physics - A method for retrieving sea wave spectra from space images of high spatial resolution has been developed for various conditions of wave generation based... 相似文献
89.
Garetsky R. G. Gribik Ya. G. Litvinovskaya R. P. Savchuk A. L. Mardosevich M. A. Khripach V. A. 《Doklady Earth Sciences》2020,494(1):688-690
Doklady Earth Sciences - The content of plant hormones (brassinosteroids) in oil samples from a number of oilfields in Belarus is determined using an enzyme immunoassay method. Brassinosteroids of... 相似文献
90.
Nemirovskaya I. A. Zavyalov P. O. Konovalov B. V. Khramtsova A. V. 《Doklady Earth Sciences》2020,492(1):387-391
Doklady Earth Sciences - The results of studying the content and composition of aliphatic hydrocarbons (AHCs) and polycyclic aromatic hydrocarbons (PAHs) in the suspended particulate matter of the... 相似文献