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1.
Lozovik P. A. Zobkova M. V. Ryzhakov A. V. Zobkov M. B. Efremova T. A. Sabylina A. V. Efremova T. V. 《Doklady Earth Sciences》2017,477(2):1510-1514
Using adsorption of organic matter (OM) on diethylaminoethyl cellulose (DEAE-cellulose) in the dynamic mode, OM is divided into autochthonous and allochthonous. Based on the experiments on BOD kinetics and OM division into components, the kinetic parameters of autochthonous and allochthonous OM transformation are established for the first time (kaut = 0.013, kall = 0.0013 day–1 at t =20°C). The activation parameters of transformation for autochthonous OM (ΔH# = 75.6 kJ/mol, ΔS# =–116.5 J/(mol K), and ΔG# = 108.3 J/mol) and allochthonous OM (ΔH# = 66.1 kJ/mol, ΔS# =–149.1 J/(mol K), and ΔG# = 108.0 J/mol) are calculated by the Arrhenius equation.
相似文献2.
For the first time in the Middle Ob Basin, new data of importance for evaluating the quality of swamp and river water were obtained, characterizing the microcomponent composition of extractive organic compounds. More than 150 compounds of natural genesis were identified. The water of oligotrophic and mesotrophic bogs shows widest diversity and maximal, almost equal masses of extractable organic substances, averaging 13357 ng/L. In the water of eutrophic bogs and taiga rivers, this characteristic is five times lower; and that in lakes is lower by more than an order of magnitude. The amount of extractive trace components is closely correlated with the concentration of water-soluble carbon of humic nature. It was established that the natural water of taiga zone identical in terms of the fulvate type differs in the composition of organic trace components and can be grouped into four clusters: (a) water of oligotrophic bogs, (b) water of mesotrophic bogs, (c) river water, and (d) water of eutrophic bogs and bog lakes. 相似文献
3.
N. I. Palshin S. R. Bogdanov G. E. Zdorovennova R. E. Zdorovennov T. V. Efremova B. Z. Belashev A. Yu. Terzhevik 《Water Resources》2018,45(5):695-705
The high-precision observational data on water temperature obtained during seven winters in a small boreal lake are considered. The spectral analysis revealed that the oscillations with a period of about 27 min prevailed in a water column. This period is close to the theoretical estimate of the first mode of the longitudinal barotropic seiche. The variability of temperature oscillations, vertical velocity, and displacement of isotherms suggest the presence of short internal waves along with seiches. The amplitude of the internal waves is an order of magnitude greater than that of seiches, and the length of internal waves is two orders of magnitude less than the linear extent of the lake. 相似文献
4.
The hydrological regime, morphological structure, and landscapes of the Indus River delta are considered, and the significant changes that took place in them during the second half of the XX century because of the large-scale hydraulic engineering activity in the river’s basin, runoff regulation, and water withdrawal for irrigation are analyzed. It is shown that the abrupt decrease in water and sediment runoff in the Indus have affected the hydrological processes in the river’s lower reaches and caused delta degradation. 相似文献
5.
Long-term data (1945–1989) collected during regular observations of water temperature on a network of Roshydromet stations in different types of water bodies in Northwestern European Russia are generalized. A number of mathematical expressions, which are relatively simple and acceptable for wide circles of researchers, are proposed for the assessment of the thermal state of water bodies. Empirical dependences of the thickness of epilimnion, the depth to thermocline, the type of thermal stratification, seasonal variations in the temperature of water surface, and individual characteristics of the “biological summer” on various geographic factors are established. Elements of thermal regime are calculated for the database of ecological-geographical typification of Karelian water bodies. 相似文献
6.
In recent years, following the Chelyabinsk event of February 15, 2013, the lower size limit for presumably dangerous near-Earth objects has been decreased manyfold (essentially, from 140 m to ~10 m). This has drawn an increased attention to the properties of the population of decameter-sized bodies, in particular, the bodies that approach the Earth from the sunward side (daytime sky). The current paper is concerned with various properties of this population. The properties of the ensemble are analyzed using both observational data from other authors and theoretical estimates obtained by cloning virtual bodies. This question is of great practical importance, as the means for detecting such bodies (for example, the SODA project) need to be developed with consideration for the requirements imposed by the population properties. We have shown that the average rate of entering near-Earth space (NES), i.e., at distances less than ~1 million km from the Earth, for decameter-sized and larger bodies from the daytime sky (elongation values of entry points less than 90°) is approximately 620 objects per year for elongation angles of the detection point <90° and approximately 220 objects per year for elongation angles of the detection point <45°. 相似文献
7.
This paper discusses the basic kinds of uncertainties arising in gravity logging. It shows how the accuracy of density determination depends on accuracy in depth determinations, as well as in reference and routine surveying. Corrections to be used in borehole surveying are listed. Field results from gravity and gamma- gamma density logging are reported. 相似文献
8.
Physics of seasonally ice-covered lakes: a review 总被引：2，自引：0，他引：2
9.
Ice phenomena terms on the water bodies of Northwestern Russia 总被引：1，自引：0，他引：1
The dependence of ice phenomena (the dates of ice freeze-up and break-up) on the air temperature and geographic factors (geographic
latitude, height above sea level, and average depth and area of lakes) is investigated on the basis of the data of long-term
observations on the water bodies of Northwestern Russia. The regression models with rather high accuracy level are proposed
not requiring a large number of input parameters unlike the deterministic models. 相似文献
10.
L. Bianchi J. Herald B. Efremova L. Girardi A. Zabot P. Marigo A. Conti B. Shiao 《Astrophysics and Space Science》2011,335(1):161-169
We describe the content and properties of UV source catalogs from GALEX’s All-Sky Imaging Survey (AIS, 5σ depth ≈19.9(FUV)/20.8(NUV) mag, in the AB system) and Medium-depth Imaging Survey (MIS, 5σ depth ≈22.6(FUV)/22.7(NUV) mag), constructed by Bianchi L., et al.: Mon. Not. R. Astron. Soc. (2010, in press). The catalogs contain 65.3/12.6 million (AIS/MIS) unique UV sources with photometric error in NUV less than 0.5 mag, over 21?435(AIS)/1579(MIS) square degrees. Matched optical data from GSC-II provide additional B, R, I photometry for the brightest sources, and SDSS provides u g r i z photometry over 7325(AIS)/1103(MIS) square degrees overlap areas. We discuss statistical properties that are relevant for understanding sample selection biases and completeness, in potential science applications of these catalogs. The FUV (1344–1786 Å) and NUV (1771–2831 Å) photometry uniquely enable selection of the hottest stellar objects, in particular hot white dwarfs (WD), which are elusive at optical wavelengths because of their hot temperatures and faint luminosities. From the GALEX-SDSS matched sources we selected ～40?000 Milky Way (MW) stars hotter than about 18?000 K (FUV-NUV?相似文献