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941.
We consider the problem of stable development of natural economical complexes from the viewpoint of basic balances in an ecological
economical system. We construct a basic dynamical model of the complex capable of predicting various scenarios of the industrial
development, consumption of natural resources, and pollution of the environment and propose a mechanism of control over the
process of development by introducing rent payments for the use of natural resources and ecological fines for the pollution
of the environment. The efficiency of the applied model is demonstrated by analysing the process of control over the concentration
of biological resources in marine media as an example. We describe the results of numerical experiments performed to show
the possibility of creation of the information technology of control over marine bioresources.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
942.
L. P. Ogorodova I. A. Kiseleva M. F. Vigasina L. V. Mel’chakova I. A. Bryzgalov D. A. Ksenofontov 《Geochemistry International》2017,55(9):814-821
The paper reports original thermochemical data on six natural amphibole samples of different composition. The data were obtained by high-temperature melt solution calorimetry in a Tian–Calvet microcalorometer and include the enthalpies of formation from elements for actinolite Ca1.95(Mg4.4Fe 0.5 2+ Al01)[Si8.0O22](OH)2(–12024 ± 13 kJ/mol) and Ca2.0(Mg2.9Fe 1.9 2+ Fe 0.2 3+ )[Si7.8Al0.2O22](OH)2, (–11462 ± 18 kJ/mol), and Na0.1Ca2.0(Mg3.2Fe 1.6 2+ Fe 0.2 3+ )[Si7.7Al0.3O22](OH)2 (–11588 ± 14 kJ/mol); for pargasite Na0.5K0.5Ca2.0-(Mg3.4Fe 1.8 2+ Al0.8)[Si6.2Al1.8O22](OH)2 (–12316 ± 10 kJ/mol) and Na0.8K0.2Ca2.0(Mg2.8Fe 1.3 3+ Al0.9) [Si6.1Al1.9O22](OH)2 (–12 223 ± 9 kJ/mol); and for hastingsite Na0.3K0.2Ca2.0(Mg0.4Fe 1.3 2+ Fe 0.9 3+ Al0.2) [Si6.4Al1.6O22](OH)2 (?10909 ± 11 kJ/mol). The standard entropy, enthalpy, and Gibbs free energy of formation are estimated for amphiboles of theoretical composition: end members and intermediate members of the isomorphic series tremolite–ferroactinolite, edenite–ferroedenite, pargasite–ferropargasite, and hastingsite. 相似文献
943.
Whole rock RbSr measurements were made on associatedbasic and acid intrusives and extrusives from the northern andsouthern ends of the Lebombo monocline with a view to determineif the acid rocks came from the mantle or from the crust. Inthe south, in Swaziland (now called Ngwame) and Zululand, rhyolitesand granophyres (age 202 14 m.y.) have an initial Si87Sr86ratio of 0.7042 0.0005; in the north, in the Nuanetsi syncline,rhyolites (age 206 13 m.y.) and granites from ring complexes(age 177 7 m.y.) have initial ratios of 0.7081 0.0008 and0.7085 0.0007, respectively. The initial ratios of the basicrocks, basalts and gabbros, vary in both areas and have a rangefrom 0.7042 to 0.7125 which can be explained by crustal contamination.The low initial ratios and isotopic homogeneity of the acidmagmas over long distances (160 km) in Swaziland and Zululandare interpreted as implying that they were derived from themantle. 相似文献
944.
Ivan I. Shevchenko 《Monthly notices of the Royal Astronomical Society》2008,384(3):1211-1220
The chaotic orbital motion of Prometheus and Pandora, the 16th and 17th satellites of Saturn, is studied. Chaos in their orbital motion, as found by Goldreich & Rappaport and Renner & Sicardy, is due to interaction of resonances in the resonance multiplet corresponding to the 121:118 commensurability of the mean motions of the satellites. It is shown rigorously that the system moves in adiabatic regime. The Lyapunov time (the 'time horizon of predictability' of the motion) is calculated analytically and compared to the available numerical–experimental estimates. For this purpose, a method of analytical estimation of the maximum Lyapunov exponent in the perturbed pendulum model of non-linear resonance is applied. The method is based on the separatrix map theory. An analytical estimate of the width of the chaotic layer is made as well, based on the same theory. The ranges of chaotic diffusion in the mean motion are shown to be almost twice as big compared to previous estimates for both satellites. 相似文献
945.
P. I. A. Kinnell 《水文研究》2005,19(14):2815-2844
Raindrop‐impact‐induced erosion is initiated when detachment of soil particles from the surface of the soil results from an expenditure of raindrop energy. Once detachment by raindrop impact has taken place, particles are transported away from the site of the impact by one or more of the following transport processes: drop splash, raindrop‐induced flow transport, or transport by flow without stimulation by drop impact. These transport processes exhibit varying efficiencies. Particles that fall back to the surface as a result of gravity produce a layer of pre‐detached particles that provides a degree of protection against the detachment of particles from the underlying soil. This, in turn, influences the erodibility of the eroding surface. Good understanding of rainfall erosion processes is necessary if the results of erosion experiments are to be properly interpreted. Current process‐based erosion prediction models do not deal with the issue of temporal variations in erodibility during a rainfall event or variabilities in erodibility associated with spatial changes in dominance of the transport processes that follow detachment by drop impact. Although more complex erosion models may deal with issues like this, their complexity and high data requirement may make them unsuitable for use as general prediction tools. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
946.
The sedimentary sequences of the Southern Uplands of Scotland host numerous lead-zinc-copper-silver vein deposits, the genesis of which has never been adequately explained. Fluid inclusion and stable isotope analysis of vein minerals from these deposits indicate that, for the vein stages studied, the mineralizing fluids were low temperature (< 150°C), high salinity (19 to 30 equiv. wt. % NaCl + CaCl2) modified meteoric waters. A consideration of the availability of such fluids throughout the geological history of the Southern Uplands suggests a Lower Carboniferous (Dinantian) age for the mineralization. 相似文献
947.
A problem of locating and comprehensively investigating ocean areas that exercise a significant influence over the migration
dynamics of fishing ranks among important problems of fisheries oceanology. Among all the environment factors affecting various
fishery situations, factors should be chosen that are constantly logged on large water areas for a long time comparable with
fishery observation time. As described in a number of works, the most suitable information for these purposes is data on the
distribution of surface temperature fields.
The problem of locating discriminative areas can then be stated as follows. For a particular fishery situation (e.g., for
the period of maximum catch in fishing season), temperature values or thermostructural features should be singled out that
are suitable to define the situation, using hydrological charts of surface temperature fields. Correlating the feature with
the areas where they were observed, we will obtain discriminative areas.
The important problem is then to develop techniques and means for algorithmically identifying areas. This relates to a vast
volume of information and complex structure.
Logical-mathematical models of locating discriminative areas are being developed at the Pacific Oceanological Institute for
some years. These models are to be for forecasting fishery situations in the NW Pacific. Techniques for representing isotherm
fields in a computer have been developed. Formal operations of comparing the fields have been proposed which aid in distinguishing
significant differences in their structure. A software for analyzing isotherm fields has been developed based on threshold
logic models.
This approach allows one not only to identify discriminative areas for relatively stable fishery situations but also to trace
their dynamics. This has been achieved due to multiple-alternative computations and the presentations of data obtained in
the form suitable for their interpretation. Some components of proposed models have been used in the system of short-term
forecasting saira and sardine fishery in the South-Kuril area. 相似文献
948.
949.
950.
FIKRY I. KHALAF 《Sedimentology》1990,37(1):155-164
Diagenetic alunite occurs with calcrete, gypcrete and silcrete deposits in a Mio-Pleistocene clastic sequence at several locations in southern Kuwait, Arabian Gulf. Based on their physical properties and textural characteristics the alunite deposits were divided into (1) chalky quartzitic alunite, (2) chalky quartz-free alunite, (3) hard pink alunitic sandstone. The chalky alunite is composed mainly of hydronium-alunite (H3O)Al3(SO4)2(OH)6, while the hard pink alunite is composed solely of well developed potassium alunite KAl3(SO4)2(OH)6. These minerals resulted from the action of sulphuric acid on clays and K-feldspars in the muddy sandstone and mudstone host sediments. The sulphuric acid is most probably produced by the oxidation of hydrogen sulphide that might have seeped in from the oil fields of this area. Four diagenetic stages are suggested for the genesis of the studied alunites: gypsification, sulphuratization, silicification and alunitization. In oil field areas, the occurrences of alunite would serve as an indicator for the presence at depth of hydrocarbons. 相似文献