摘要:

The increasing awareness of the potential environmental impacts of heavy metal pollution and the techno‐economic limitations of conventional metal removal techniques have led to the study alternate, inexpensive methods. Lignin, an easily available polymer from pulp and paper industry waste, appears to he an attractive material for heavy metal removal.

ISSN:0360-1226    

DOI:10.1080/10934528909375521

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Much attention has been given to groundwater contamination due to the release of hazardous constituents from treatment and disposal facilities. Since some of the constituents entered groundwater aquifers in much shorter times than had been calculated, regulatory agencies have become concerned that hazardous constituents may be escaping from units not currently regulated under hazardous waste management programs. One of the major concerns of regulators is that unlined earthen surface impoundments in industrial wastewater treatment trains may be leaking heavy metals such as chromium and other hazardous constituents into the groundwater. The Environmental Protection Agency is moving toward bringing such impoundments under the Resource Conservation and Recovery Act (RCRA) regulations. In addition, EPA is now proposing to list hexavalent chromium as a hazardous air pollutant due to its possible release from the mist of cooling towers, citing hexavalent chromium's potent carcinogenicity as the primary concern. While such a listing would primarily affect worker exposure, leakage of chromium from surface impoundments could enter groundwater sources and carry exposures far beyond industrial facilities.

ISSN:0360-1226    

DOI:10.1080/10934528909375522

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Twenty‐five blood and biopsy fat samples were collected from donors with and without a Down's Syndrome child, and analyzed for 29 selected polychlorinated biphenyl isomers. Differences in polychlorinated biphenyl isomer levels in blood and adipose tissue of donors with or without a Down's Syndrome child were not statistically significant. Most polychlorinated biphenyl Isomers observed in blood were also detected in adipose tissue, except for the 3,4,4'‐trichlorobiphenyl, which was sometimes observed in blood, but not in adipose tissue.

ISSN:0360-1226    

DOI:10.1080/10934528909375523

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Surface and ground‐water quality were monitored in the Appoquinimink Watershed as part of the Appoquinimink Rural Clean Water Project (RCW)). Surface water was monitored for seven years and ground water was monitored for three years. As part of the RCWP plan, conservation tillage, fertilizer management and pesticide management were the most widely used best management practices.

ISSN:0360-1226    

DOI:10.1080/10934528909375524

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The changes in some metal components of water hyacinth by exposure to cadmium, nickel with or without surface‐active agents are determined. Metal contents of Cd, Ni, Al, Ca, Si, Mn in tops and roots were changed in relatively short time by treatment with Cd or Ni. The values of concentration factors are reduced in both tops and roots under the presence of the anionic surface‐active agents.

ISSN:0360-1226    

DOI:10.1080/10934528909375525

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

A continuous counter‐current leaching of shikonin from Arnebia Documbens (Baraginoceae) was undertaken using different types of organic solvents. The optimum number of actual stages and the most powerful solvent were determined. The leaching batteries had been linked with the distillation column allowing complete recycling of the waste solvent and minimizing environmental disposal. The method gave a high rate of solvent recovery, eliminated lossses of solvent to the environment and an excellent washfastness dyestuff product was obtained.

ISSN:0360-1226    

DOI:10.1080/10934528909375526

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Blood samples from 200 Saudi Arabian school boys, aged 6–8 years, were analyzed for their Pb concentrations by graphite furnace atomic absorption spectrometry, Mean Blood‐Pb concentration was found to be 6.9 (±3.4) ug/dl. The blood samples were also examined for some hematological parameters : total counts of erythrocytes and leucocytes, hematocrit, mean corpuscular volume, hemoglobin, mean corpuscular hemoglobin concentration, and basophilic stippling, using a Coulter Counter. All values obtained were within the ‘normal ranges’. However, the hematological effects of sub‐toxic levels of Pb in blood were assessed by considering the seven cases whose Blood‐Pb values were between 15 ‐ 25 ug/dl. The data indicate that sub‐toxic levels of Pb in blood may be related to early stages of microcytic anemia.

ISSN:0360-1226    

DOI:10.1080/10934528909375527

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Effect of paraquat and trifluralin on the growth of a Kuwaiti soil isolate,Trichoderma viridehas been studied. The former herbicide inhibited the growth of the microorganism while the latter had little effect on its growth pattern. An analysis of the fatty acid pattern after interaction of the microorganism with paraquat revealed a consistent decrease in the saturated fatty acids content while a consistent increase in polyunsaturated fatty acids was observed. A possible explanation for the changes in fatty acids of the organism is offered.

ISSN:0360-1226    

DOI:10.1080/10934528909375528

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Molasses stillage 1s a pyproduct of the sugar cane Industry in Egypt.Candida utilisandPaecilomyces variotiiwere used separately and in a mixed culture for treatment of this still age and biomass production. A two‐steps aerobic batch process has been adopted. The distillery waste water was treated withC. utilis1n the first step and withP..variotii1n the second step, which was carried out on the supernatant from the first step.

ISSN:0360-1226    

DOI:10.1080/10934528909375529

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Potassium permanganate (KMnO4) has been as an oxidant for decades to remove and control iron and manganese in surface water supplies. This oxidant was investigated for its ability to inactivate bacteriophage MS‐2 and thereby reduce the amount of chlorine required for a 99.99% reduction of virus during drinking water treatment as required by the U.S. Environmental Protection Agency's Surface Treatment Rule (U.S. EPA 1989). Experiments were conducted in potassium monophosphate buffer (pH 6.0 and pH 8.0) at 7°C. At time intervals from 0 to 30 min, samples were taken and mixed immediately with a solution of sodium thiosulfate:sodium thioglycolate to neutralize residual KMnO4. At 0.5 and 5.0 mg/L KMnO4, results showed no significant differences (p<:0.05) in the inactivation of MS‐2 between experiments done at pH 6.0 and those at pH 8.0. Ninety‐nine percent of the virus was inactivated after 50, 35, and 5 min of exposure time to 0.5, 1.5, and 5.0 mg/L potassium permanganate at pH 8.0, respectively. It appears that at the currently used levels of KMnO4(up to 10 mg/L), this oxidant may supplement high levels of chlorination in the disinfection of water systems.

ISSN:0360-1226    

DOI:10.1080/10934528909375530

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor