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101.
N. V. Kabychenko G. G. Kocharyan D. V. Pavlov A. N. Besedina 《Seismic Instruments》2012,48(3):214-217
A procedure for eliciting displacements in tidal waves from seismograms of broadband velocimeters like STS-2 and KSESH-R and the evaluation conversion of these displacements into vertical or volumetric deformation is proposed. 相似文献
102.
D. V. Lukashev 《Water Resources》2010,37(3):394-398
Variations in Cd, Cr, Cu, and Fe concentrations in water and the soft tissues of bivalved mollusks Anodonta anatina and Unio
tumidus along the Southern Bug River channel are examined. Fe concentration was found to be somewhat higher than the MAC.
Cd, Cr, and Cu concentrations in water met the drinking water standards. The comparison of individual reaches of the channel
in terms of heavy metal concentrations in mollusks allowed polluted river reaches to be identified. The highest Fe concentrations
in the soft tissues of mollusks were recorded near the river source. The mollusks in the middle and lower reaches of the Southern
Bug featured high accumulation of Cd, Cr, and Cu. 相似文献
103.
K. K. Edel’shtein A. V. Goncharov M. G. Ershova V. V. Puklakov N. G. Puklakova D. I. Sokolov 《Water Resources》2010,37(2):234-244
The methodological features and results of two soil surveys of the Senezh Reservoir carried out in 1992 and 2006 as a part
of multidisciplinary limnological studies of this large recreation water body with the aim to monitor its ecological state
and prepare recommendations for water protection measures are analyzed 相似文献
104.
Integrative fuzzy set pair model for land ecological security assessment: a case study of Xiaolangdi Reservoir Region, China 总被引:5,自引:1,他引:4
Shiliang Su Xia Chen Stephen D. DeGloria Jiaping Wu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2010,24(5):639-647
Due to the increasingly serious ecological degradation of land systems, the land ecological security issues have attracted
more and more attention of policy makers, researchers and citizens. Aiming at overcoming the disadvantages in subjectivity
and complexity of the currently used assessment methods, an integrative fuzzy set pair model for assessing the land ecological
security was developed by integrating fuzzy assessment and set pair analysis (SPA). The approximate degree of land ecological
security to the optimal standard set was calculated to describe the secure level by combining multiple indices. The indices
and weights were determined by a pressure-state-response model and the fuzzy analytic hierarchy process (AHP), respectively.
Aided by a geographic information system, this model was applied to evaluate comprehensively the status of land ecological
security in Xiaolangdi Reservoir Region, China, taking the administrative division as the assessment unit. The results showed
that 20% of the total area maintained a slightly secure status, while 50% of the study area was of a middle or seriously low
grade of land ecological security. The remaining portion (30%) was the most ecologically insecure. From the spatial prospective,
obvious variations were observed. The land eco-security gradually decreased from the Xiaolangdi Dam to its surrounding regions.
It was concluded that the status of the integral land ecological security of Xiaolangdi Reservoir Region was in the middle
level, and increasingly intense human activities speeded up the degradation of regional land ecosystem in recent years and
thus induced the crisis of land ecological security. 相似文献
105.
106.
S.?V.?VyatkinEmail author G.?Yu.?Kriulina V.?K.?Garanin D.?G.?Koshchug E.?A.?Vasilyev 《Moscow University Geology Bulletin》2018,73(2):161-165
Two samplings of 65 diamond crystals divided by the intensity of a slow X-ray luminescence component are studied from the Arkhangel’skaya and Karpinskogo-1 pipes. IR and EPR spectroscopies revealed a relationship between the nitrogen A and P2 centers of the diamonds and the presence of a slow X-ray luminescence component. Its absence in most diamonds with high content of P1 (C) centers is explained by the low number of A and P2 centers. 相似文献
107.
108.
109.
V. L. Afanasjev I. D. Karachentsev V. A. Lipovetsky H. Lorenz D. Stoll 《Astronomische Nachrichten》1979,300(1):31-36
Spectra of three high-redshift quasars discovered on low-dispersion objective prism plates were obtained. We present the emission line identifications and redshifts of the objects. Equivalent widths, line widths and low-resolution line profiles are given characterizing the quasar emission region. The Lyα and CIV equivalent widths indicate that the considered quasars are luminous objects at high redshift. Both these equivalent widths are too low by a factor 4, whereas the N V/Lyα ratio is 5 times larger than predicted by the photoionisation models. The line profiles are compared with logarithmic, electron-scattering and Gaussian profiles. In all the spectra rich absorption line systems are evident. 相似文献
110.
D. O. Gough 《Solar physics》2017,292(5):70
It has been argued (Gough and McIntyre in Nature 394, 755, 1998) that the only way for the radiative interior of the Sun to be rotating uniformly in the face of the differentially rotating convection zone is for it to be pervaded by a large-scale magnetic field, a field which is responsible also for the thinness of the tachocline. It is most likely that this field is the predominantly dipolar residual component of a tangled primordial field that was present in the interstellar medium from which the Sun condensed (Braithwaite and Spruit in Nature 431, 819, 2004), and that advection by the meridional flow in the tachocline has caused the dipole axis to be inclined from the axis of rotation by about \(60^{\circ}\) (Gough in Geophys. Astrophys. Fluid Dyn., 106, 429, 2012). It is suggested here that, notwithstanding its turbulent passage through the convection zone, a vestige of that field is transmitted by the solar wind to Earth, where it modulates the geomagnetic field in a periodic way. The field variation reflects the inner rotation of the Sun, and, unlike turbulent-dynamo-generated fields, must maintain phase. I report here a new look at an earlier analysis of the geomagnetic field by Svalgaard and Wilcox (Solar Phys. 41, 461, 1975), which reveals evidence for appropriate phase coherence, thereby adding support to the tachocline theory. 相似文献