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761.
Although there is published information on the mechanism of sedimentary pyrite formation resulting from bacterial reduction of sulfate, little is known about the distribution of forms of sulfur, including organic, in peats. In order to increase understanding of the geochemistry of sulfur in coals, we have determined distributions of forms of sulfur in five cores of saline peat and one of brackish peat, all from areas near the Shark River and Whitewater Bay in the coastal swamps of south Florida. All concentrations vary widely with depth. Total sulfur concentrations range up to 6% of dry solids. Minor amounts of sulfur are present as H2S, S0, SO42−, and acid-soluble sulfide, but the principal forms are usually pyritic and organic. The ratio, organic/pyritic, is highly variable, but at a majority of levels in a profile is considerably greater than unity. It is inferred that topochemical factors are important in determining the distribution of sulfur forms in any element of volume.  相似文献   
762.
Zagidullin  A. A.  Usanin  V. S.  Petrova  N. K.  Nefedyev  Yu. A.  Andreev  A. O.  Gudkova  T. V. 《Astronomy Reports》2020,64(12):1093-1106
Astronomy Reports - The work is devoted to the study of the physical libration of the Moon. Interest in the traditional topic related to the rotation of the Moon is stirred up by the activity of...  相似文献   
763.
Doklady Earth Sciences - The interaction between the atmosphere and the lithosphere in the minute range of periods is considered. The technique of assessment of the influence of atmospheric...  相似文献   
764.
The weathering crust of the Beden ultrabasite massif (the basin of Big Laba River) is identified and studied. Anomalously high contents of noble metals (Au, Pt, Pd) are revealed in the basal horizon of the Jurassic part of the weathering crust. For this reason we suspect an existence of a belt of noble metal miner-alization in the Paleozoic ultrabasites in the Peredovoi Range of the Northern Caucasus.  相似文献   
765.
We solve a plane problem of linear baroclinic seiches in closed rotating basins of variable depth with two-layer density stratification. In the long-wave approximation, we get a boundary-value problem for a system of ordinary differential equations and propose a numerical procedure for finding internal seiches. The analytic solutions of the problem are obtained for a basin of constant depth. The numerical analysis of seiches is performed for the distributions of depth corresponding to the zonal and meridional sections of the Black Sea and model basins including the cases of a shelf zone and an underwater ridge. It is shown that the baroclinic seiches become more intense in shallow-water regions and that the intense longshore currents caused by Earth’s rotation are formed in the shelf zones and over the underwater ridges.  相似文献   
766.
767.
Vul'fson  A. N.  Borodin  O. O. 《Water Resources》2000,27(6):625-632
An intergral model of a transient vertical impulse–buoyant jet is suggested. The model contains a universal equation describing the propagation of the upper boundary of the convection front depending on the strength of the point source of buoyancy and momentum. The convective regime of jet propagation is considered, which includes a class of self-similar solutions corresponding to the buoyancy sources, whose strength varies with time following power and exponential laws. The obtained numerical solutions are compared with available experimental data on the profiles of vertical velocity and buoyancy on the jet axis.  相似文献   
768.
Wind erosion of soil is an appreciable but unstudied event following fires in cold desert. We examined aeolian transport of sediment for 1 year following fire in semi-arid shrub steppe on loess soils in southern Idaho, USA. Sediment collectors were used to determine horizontal mass transport of soil and saltation sensors and anemometers were used to determine saltation activity (fraction of time having saltation) and threshold wind speed in an area burned in August and an unburned control site. Horizontal mass transport (per 30-day period) was negligible in the unburned area, but in the burned area was 5.40 kg m?1 in October and decreased to 2.80 kg m?1 in November and 0.32 kg m?1 in December. Saltation activity was high enough to determine threshold wind speeds only in the burn site during fall, when values ranged from 10.0 to 10.6 m s?1. Sediment flux and saltation activity in the burned site became much less pronounced following the emergence of herbaceous vegetation in the spring. Post-fire sediment flux in the shrub steppe we examined was of greater magnitude but shorter duration than post-fire fluxes in warm deserts or sandier regions that experience more frequent wind erosion.  相似文献   
769.
Book reviews     
APPLIED GEOGRAPHY: Issues, Questions and Concerns (Geo Journal Library Vol. 15) edited by M. S. Kenzer. 16 × 24 cm, x and 210 pages. Kluwer: Dordrecht 1989 (ISBN 0 7923 04381).

WINE AND THE VINE: An Historical Geography of Viticulture and the Wine Trade by T. Unwin. 16 × 24 cm, xvi and 409 pages. Routledge: London 1991 (ISBN 0 415 13120 6) $A155.00 (hard); distributed by The Law Book Co.

WATERFRONT SYDNEY 1860–1920 by G. Aplin and J. Storey. 26 × 18 cm. 144 pages. Allen & Unwin: Sydney 1991 (first published 1984) (ISBN 1 86373 098 2) $A24.95 (soft).

Australian Geographer 23 (2), November 1992

INDUSTRIAL LOCATION: Principles and Policies (Second Edition) by K. Chapman and D. F. Walker. 15 × 23 cm, xiii and 322 pages. Basil Black‐well: Oxford 1991 (ISBN 0 631 16789 7) $A39.95 (soft).

INTERNATIONALISATION OF AUSTRALIA'S SERVICE INDUSTRIES by J. V. Langdale. 17 × 25 cm, iv and 373 pages. Australian Government Publishing Service, for Department of Industry, Technology and Commerce: Canberra 1991 (ISBN 0 644 13841 6).

TOURISM AND GOLD IN KAKADU: The Impact of Current and Potential Natural Resource Use on the Northern Territory Economy by B. Knapman, O. Stanley and J. Lea. 21 × 29 cm, vi and 49 pages. North Australia Research Unit, Australian National University: Darwin 1991 (ISBN 0 7315 1179 4).

ABORIGINAL AUSTRALIA AND THE ‘NEW FEDERALISM’ INITIATIVE (Discussion Paper No. 2) by G. J. Crough. 14 × 21 cm, 42 pages. North Australia Research Unit, Australian National University: Darwin 1991 (ISBN 0 7315 1325 8).

AUSTRALIAN NATIONHOOD AND OUTBACK INDIGENOUS PEOPLES (Discussion Paper No. 1) by P. Jull. 14 × 21 cm, 38 pages. North Australia Research Unit, Australian National University: Darwin 1991 (ISBN 0 7315 1309 6).

MIGRATION AND DEVELOPMENT IN THE SOUTH PACIFIC (Pacific Research Monograph No. 24) edited by J. Connell. 17 × 25 cm, xii and 199 pages. National Centre for Development Studies, Australian National University: Canberra 1990 (ISBN 0 07315 0668 5) $A25.00 (soft).

POPIULESIN BLONG HONIARA: Olketa Popiulesin Map Blong 1986 Sensis. HONIARA: 1986 Census Atlas (Statistics Office Occasional Paper No. 4 / Board of Development Studies Monograph No. 1) by A.C. Walsh. 21 × 29 cm, vii and 95 pages. Department of Statistics: Honiara and Board of Development Studies, Massey University: Palmerston North 1990 (ISSN 0114 8834) $NZ34.00 in New Zealand, $NZ38.00 elsewhere (soft).

DOI MOI: Vietnam's Renovation Policy and Performance (Political and Social Change Monograph No. 14) edited by D. K. Forbes, T. H. Hull, D. G. Marr and B. Brogan. 15 × 22 cm, xiv and 263 pages. Department of Political and Social Change, Australian National University: Canberra 1991 (ISBN 0 7315 1303 7).  相似文献   

770.
Proposed are the methods and software package that enable estimating automatically the degree of the pollution of annual and long-term river runoff at the joint processing of large volumes of standard (routine) hydrological and hydrochemical information. As a result of computations, the individual quality certificate of river runoff was created for the part of the river under study. Computation methods include regulations concerning the parameters that connect the water runoff volume with water quality; the parameters that may connect the computation of the pollution degree using RD 52.24.643-2002 adapted for the partial volumes of the annual runoff according to these methods, with the subsequent classification of the pollution degree. The computation technique was worked out and used for the first time. The informativeness of estimates is demonstrated for one of the discharge section lines of the Selenga River.  相似文献   
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