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61.
The best interest of any company is well served when responsibility for procurement of vapor control equipment is properly fixed. From discovery of need, to final operation of the equipment, many events must occur and much effort must be expended. In many petroleum industry marketing terminals today, decentralization of control has forced terminal managers to become cost center managers as well as distribution facility managers, and this added responsibility is valuable. Who else is in a better position to evaluate the true operating costs of any equipment and to carry out the responsibility of finding the right equipment for the job at hand? Where companies employ central engineering staffs, the necessary support studies should be made available to the terminal manager so that he can understand and review: (1) the capital investment and related depreciation expense; (2) the need for preventive maintenance programs as suggested by bidding equipment suppliers; (3) the need for local contractors to bid on preventive maintenance programs; (4) company maintenance routines and all labor expense involved; and (5) budget preparation for both capital and expense budgets.  相似文献   
62.
Mercury occurs naturally in the environment and can be found in elemental (metallic), inorganic, and organic forms. Modern uses for mercury include chemical manufacturing, thermometers, and lighting (mercury vapor and fluorescent lamps). The chemical and allied products industry group is responsible for the largest quantity of mercury used in the United States. Mercury, particularly the organic methylmercury form, is a potent neurotoxin capable of impairing neurological development in fetuses and young children and of damaging the central nervous system of adults. Mercury regulations span multiple federal and state environmental statutes, as well as multiple agency jurisdictions. In August 2007, the U.S. Environmental Protection Agency's (US EPA's) Office of Superfund Remediation and Technology Innovation (OSRTI) published a report titled “Treatment Technologies for Mercury in Soil, Waste, and Water.“ The report identifies eight treatment technologies and 57 projects, 50 of which provide performance data. This information can help managers at sites with mercury‐contaminated media and generators of mercury‐contaminated waste and wastewater to identify proven and effective mercury treatment technologies; screen technologies based on application‐specific goals, characteristics, and costs; and apply experiences from sites with similar treatment challenges. This article provides a synopsis of the US EPA report, which is available at http://clu‐in.org/542R07003 . © 2007 Wiley Periodicals, Inc. *
  • 1 This article is a U.S. Government work and, as such, is in the public domain of the United States of America.
  •   相似文献   
    63.
    Techniques for enhancing the biodegradation of oil-contaminated fine soils in a slurry-phase bioreactor were investigated. Using a model system consisting of kaolin particles containing adsorbed n-dodecane as a diesel fuel surrogate, we investigated how increasing the temperature and adding a surfactant and various hydrophobic support media affected the biodegradation rate of n-dodecane. Increasing the temperature from 25 to 35 degrees C decreased the time required for complete degradation of n-dodecane by 30%, from 110h to 80h. Addition of the surfactant polyethylene glycol p-1,1,3,3-tetramethylbutylphenyl ether decreased the degradation time to less than 48h at 35 degrees C, although a high concentration of the surfactant (3000mgl(-1)) was required. We suspect that the surfactant increased the degradation rate by solubilizing the n-dodecane into the solution phase in which the microorganisms were suspended. We tested five types of organic polymers as support media for the microorganisms and found that the biodegradation time could be reduced by approximately 50% with a support medium made from polyurethane; in the presence of this medium, only 36h was required for complete decomposition at 35 degrees C. The reduction in the degradation time was probably due to transfer of the n-dodecane from the soil to the support medium, which improved contact between the n-dodecane and the microorganisms. The polyurethane support medium bearing the microorganisms was stable and could be reused.  相似文献   
    64.
    To delineate the natural history of fetal multicystic dysplastic kidneys (MDKs), all cases that were prenatally detected in the Prenatal Diagnosis Center of the University of Virginia from September 1985 to 31 August 1988 were reviewed. All patients were followed through the Center with serial ultrasound evaluations at approximately 4-week intervals, and each liveborn infant was evaluated and followed by one of the authors (S.S.H.) Of the 14 cases detected, ten were detected in the second trimester, the earliest at 16·5 weeks' gestation. Of the nine fetuses with non-lethal disease, there were two cases in which the lesion remained unchanged during observation. Both had an initial diagnosis in the third trimester. In those cases diagnosed in the second trimester (7), all showed an initial increase in the size and number of cysts, followed by involutional changes either in utero (2) or in the neonatal period (3). Two infants had immediate surgical removal of the MDK, one because of respiratory compromise, and the other because of an uncertain diagnosis on renal scan. Abnormalities of the contralateral kidney were found in 7 of 14 fetuses. Five were lethal conditions. Associated non-renal abnormalities were common in bilateral MDK (80 per cent), but rare in unilateral MDK (11 per cent).  相似文献   
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    A variety of studies have established the value of shaded coffee plantations as habitat for birds. While the value of birds as biological controls in coffee has received some attention, the interactions between birds and other predators of insects have not been tested. We used exclosures to examine the effects of vertebrate predators on the arthropods associated with coffee, in particular the coffee leafminer (Leucoptera coffeella) and the flatid planthopper Petrusa epilepsis, in a shaded coffee plantation in Puerto Rico. We used a 2 x 2 factorial design with four treatments: exclusion of birds, lizards, birds and lizards, and control (no exclusion). Abundance of insects > 5 mm increased when birds or both birds and lizards were removed. Birds and lizards had an additive effect for insects < 5 mm and for all insects combined. Coffee leafminers showed a weak response to removal of predators while planthopper abundance increased significantly in the absence of avian predators. Arthropod predators and parasitoids did not differ significantly between treatments. Our findings suggest that vertebrate insectivores have an additive effect on insects in coffee and may help control abundances of some coffee pests. Equally important, we present evidence suggesting that they do not interfere with other known natural enemies of coffee pests.  相似文献   
    67.
    This paper summarizes the results of a primarily qualitative (with certain quantitative elements) socio-ecological study on three Greek islands of the Aegean Archipelago to characterize fire science and policy at regional and local levels, and perceptions of fire risk. Among the most important factors influencing dynamics of fire regimes on the islands are changing land use patterns and practices, and changes in climate and fuel conditions. While use of scientific information is not widespread, there are individuals in all three islands who regularly consult scientific sources. Although fire policy is largely controlled at the national and European Union levels, local activity also occurs, most notably through the volunteer fire fighting organizations, interactions with local officials, and public education efforts. However, though seen as important, significant lack of financial support and resources exist to support prevention and pre-suppression programs. Prevention of fires on the islands, including the use of prescribed burning, is relatively inadequate, and while an intense interest in preventing the loss of communities and ecosystems is frequently encountered, public participation in fire prevention remains limited. The findings suggest that relying on local knowledge, in combination with fire managers’ decision-making abilities, could improve fire management options and reduce wildfire suppression costs and ecological disasters.  相似文献   
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    The ability to pay for water and wastewater services is a growing issue in the developed world. To this point in time, utilities have helped customers grappling with affordability issues using different types of customer assistance programs (CAPs). Income‐based billing approaches differ from CAPs in that bills are structured so as to be affordable for customers at the outset. Recently, the City of Philadelphia implemented an innovative program to work towards resolving the affordability problem in their city using income‐based billing. This tiered assistance program or TAP structures bills for water, wastewater, and stormwater services to program enrollees’ income. Given the innovative nature of the program, this paper describes the rollout of TAP and assesses the impact of the program on customers and utility revenues. The paper closes with a critical assessment of TAP and considerations for utilities evaluating the implementation of similar programs.  相似文献   
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