Modelling atmospheric dispersal of the Chernobyl release across Europe     

H. M. ApSimon  J. J. N. Wilson 《Boundary-Layer Meteorology》1987,41(1-4):123-133

At the time of the Chernobyl accident little was known about the magnitude and time pattern of the release from the damaged reactor. This paper describes the detective work done in the weeks following the accident to assess the release and its dispersal across Europe; also calculations done since the USSR presentations in Vienna at the end of August 1986 and some estimates of longer term collective dose commitment. To conclude some general remarks are made about the implications of the Chernobyl accident for technical support in emergency procedures for any future nuclear accident.  相似文献   

In Situ Biorestoration as a Ground Water Remediation Technique   总被引：1，自引：0，他引：1  

John T Wilson  Lowell E. Leach  Michael Henson  Jerry N. Jones 《Ground Water Monitoring & Remediation》1986,6(4):56-64

In situ biorestoration, where applicable, is indicated as a potentially very cost-effective and environmentally acceptable remediation technology. Many contaminants in solution in ground water as well as vapors in the unsaturated zone can be completely degraded or transformed into new compounds by naturally occurring indigenous microbial populations. Undoubtedly, thousands of contamination events are remediated naturally before the contamination reaches a point of detection. The need is for methodology to determine when natural biorestoration is occurring, the stage the restoration process is in, whether enhancement of the process is possible or desirable, and what will happen if natural processes are allowed to run their course.
In addition to the nature of the contaminant, several environmental factors are known to influence the capacity of indigenous microbial populations to degrade contaminants. These factors include dissolved oxygen, pH, temperature, oxidation-reduction potential, availability of mineral nutrients, salinity, soil moisture, the concentration of specific pollutants, and the nutritional quality of dissolved organic carbon in the ground water.
Most enhanced in situ bioreclamation techniques available today are variations of hydrocarbon degradation procedures pioneered and patented by Raymond and coworkers at Suntech during the period 1974 to 1978. Nutrients and oxygen are introduced through injection wells and circulated through the contaminated zone by pumping one or more producing wells.
The limiting factor in remediation technology is getting the contaminated subsurface material to the treatment unit or units, or in the case of in situ processes, getting the treatment process to the contaminated material. The key to successful remediation is a thorough understanding of the hydrogeologic and geochemical characteristics of the contaminated area.  相似文献   

Determination of Microbial Cell Numbers in Subsurface Samples   总被引：2，自引：0，他引：2  

JoAnn J. Webster  Ginger J. Hampton  John T. Wilson  William C. Ghiorse  Franklin R. Leach 《Ground water》1985,23(1):17-25

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Metal accumulation rates in northwest Atlantic pelagic sediments     

J Thomson  M.S.N Carpenter  S Colley  T.R.S Wilson  H Elderfield  H Kennedy 《Geochimica et cosmochimica acta》1984,48(10):1935-1948

Measurements of ²³⁰Th, ${}^{87}\text{Sr}{}^{86}\text{Sr}$ and twenty-four metals were made on cores from the Nares Abyssal Plain. The sediment is characterized by slowly-accumulating (0.3–0.7 g/cm² 10³ yr) pelagic red clays and rapidly deposited grey clays transported by turbidity currents. Despite their colour differences and the enrichment of Mn, Fe, Cu, Co, Ni, Zn, V and, to a lesser degree, the rare earths in the red clays, Sr isotope evidence demonstrates that the clays have the same terrigenous origin. The excesses of metals in the red clays have been attributed to metal removal from the water column and a comparison with the grey clays has enabled the authigenic fluxes of metals to be estimated. The fluxes obtained are in the ranges 20–50 μmol/cm² 10³ yr for Mn and Fe, 0.1–0.4 μmol/cm² 10³ yr for Cu, Co, Ni, Zn, V, Sr and Ce, 10–20 nmol/cm² 10³ yr for La and Nd, and 0.5-3 nmol/cm² 10³ yr for Sm, Eu, Gd, Dy, Er and Yb. Authigenic fluxes of Y, Nb, Cr, Zr, Rb, U and Th were not resolvable. Fluxes appear to be near constant on the Plain but comparison with other areas shows that they are quite variable both between and within ocean basins. The chief factor controlling authigenic fluxes is the geochemical abundances of the elements but fractionation within both the transition element and rare earth series can be recognized from inter-element comparisons and from differences in fluxes between Atlantic and Pacific red clays corresponding to the oceanic reactivities of the elements.  相似文献   

Non-steady state diagenetic record in eastern equatorial Atlantic sediments     

J. Thomson  T.R.S. Wilson  F. Culkin  D.J. Hydes 《Earth and Planetary Science Letters》1984,71(1):23-30

The radiocarbon age profile of a sediment core from the eastern equatorial Atlantic shows a marked decrease in both clay and carbonate accumulation rates at the end of the last glacial period, with overall rates of 3.2 and 8.1 cm/kyr for the Holocene and late glacial respectively. The transition from glacial to postglacial conditions recorded in the sediments at 39 cm is above the visual Fe(II)/Fe(III) redox boundary at 48 cm which has been used in the past to identify the glacial section, and even further above the increase in preserved organic carbon content at 55 cm. It is concluded from the present organic carbon profile, and recent observations in this area and elsewhere, that organic diagenesis in these sediments is not steady state. Instead it is suggested that the uppermost glacial sediments lost carbon through oxic remineralisation at the change to postglacial conditions, and that this process is now continued with nitrate as the electron acceptor. These observations suggest that the double MnO_x solid phase peak which occurs in these and similar sediments is a direct consequence of an adjustment of the oxic layer depth following the decrease in carbon flux at the onset of the Holocene.  相似文献   

A study on hydrogen peroxide in the atmosphere   总被引：1，自引：0，他引：1  

Su Weihan  Li Wei  Ding Guoan  W.E. Wilson 《大气科学进展》1989,6(4):509-515

Hydrogen peroxide (H2O2) concentrations were measured at two sites. One was on Lushan Mountain in May, 1987. The other was in Beijing in August, 1987 and in December, 1986. The automated fluorometric method was used for the determination of H2O2. The concentrations of H2O2 ranged from approximately 0.50 to 4.32 ppb on Lushan Mountain. The concentrations of H2O2 ranged from approximately 0.05 to 1.49 ppb in August in Beijing, and it was only 0.01 ppb in December in Beijing.  相似文献   

In Situ Bioreclamation: A Cost-Effective Technology to Remediate Subsurface Organic Contamination     

Scott B. Wilson  Richard A. Brown 《Ground Water Monitoring & Remediation》1989,9(1):173-179

In situ bioreclamation is a proven technology that cost-effectively treats organic contamination in subsurface environments. As a remediation strategy, it reduces both the contamination dissolved in ground water, as well as residual soil-bound contamination.
To maximize biodegradation, the technology is applied after conducting laboratory studies. Application of the technology involves infiltrating necessary nutrients to the contaminated subsurface.
Results of a specific case study indicate excellent performance with rapid cleanup of petroleum hydrocarbon contamination from soils and ground water.
Costs associated with in situ bioreclamation technology showed a savings of approximately 50 percent over simple pump-and-treat technology. Time frame for cleanup was shown to be approximately 30 percent of the projected time frame of simple pump-and-treat technology.  相似文献   

GPS Solutions for the Verification and Resolution of GIS Coordinate Database     

Ramesh L. Shrestha  Jim Cameron  Matt Wilson 《GPS Solutions》1995,1(2):129-138

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FTIR studies of deuterium incorporation into coal,associated mineral matter and hydrogenation residues     

A.M. Vassallo  P.M. Fredericks  M.A. Wilson 《Organic Geochemistry》1983,5(2):75-85

An Australian bituminous coal (Liddell) was hydrogenated with hydrogen/deuterium gas mixtures in the presence of tetralin. The nature and forms of deuterium in the insoluble (residue) products were investigated by Fourier transform infrared spectroscopy (FTIR).The results show that deuterium enters and is incorporated into not only aromatic and aliphatic organic structures in the coal but also hydroxyl groups of associated kaolinite. The results suggest that deuterium may be incorporated into organic structures in the coal via an additional reaction pathway involving exchange with kaolinite. This pathway of transfer of deuterium or hydrogen to the coal has not previously been demonstrated.  相似文献   

Nuclear magnetic resonance spectroscopy of soils and related materials. Relaxation of ¹³C nuclei in cross polarization nuclear magnetic resonance experiments     

Michael A. Wilson  Ronald J. Pugmire  David M. Grant 《Organic Geochemistry》1983,5(3):121-129

Relaxation of ¹³C nuclei in a peat, a soil, and three soil fractions have been investigated in order to improve structural resolution and to investigate quantification of various carbon types. Rotating frame spin lattice relaxation times (T_1?'s) and transverse relaxation times (T₂′'s) are similar to those observed for coals. T₂′'s of carbons in different magnetic environments differ sufficiently that spectra can be obtained containing only nonprotonated carbon and methyl substituents if a 40 μsec delay without decoupling is inserted into the pulse programme before data acquisition (dipolar dephasing). Provided quantitative data is obtained in simple cross polarization experiments and allowance is made for loss in signal intensity of nonprotonated carbon during dipolar dephasing, then the fraction of aromatic carbon which is protonated in the samples can be determined.  相似文献