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131.
Jeff Gamlin Douglas Downey Paul Favara Lonnie Duke Glenn Anderson 《补救:环境净化治理成本、技术与工艺杂志》2017,27(3):9-17
Travis Air Force Base, California, has accelerated the pace of remediation while reducing long‐term costs and cutting greenhouse gas production. This has been achieved through optimizing existing systems and processes, adopting greener cleanups best management practices, and testing and implementing innovative “green” technologies. By optimizing and replacing existing systems that used energy‐intensive infrastructure, and by promoting the use of innovative in situ technologies, the US Air Force (Air Force) led team comprised of the Air Force Civil Engineer Center, the US Army Corps of Engineers, the performance‐based contractor CH2M, and the regulatory agencies consisting of the US Environmental Protection Agency, the California Water Board, and the California Department of Toxic Substances Control, has reduced annual system operation and maintenance costs by over $200,000 per year, while reducing annual carbon dioxide production by approximately 930 tons per year. As a result of these actions, chlorinated solvent source areas have been reduced by over 99 percent in some cases, and the predicted cleanup time frame for multiple sites has been reduced by several decades. This article provides a case study for implementation of cost‐effective greener cleanup actions, and summarizes the approach taken by the Air Force led team to complete the greener cleanups self‐declaration process consistent with the ASTM International's E‐2893 Standard Guide for Greener Cleanups. 相似文献
132.
The role of natural disaster in individual and relational adjustment in Sri Lankan mothers following the 2004 tsunami 下载免费PDF全文
Alyssa Banford David C. Ivey Thulitha Wickrama Judith Fischer Anne Prouty Douglas Smith 《Disasters》2016,40(1):134-157
The purpose of this study is to examine the associations between maternal mental health distress symptoms, including depression and post‐traumatic stress disorder, the extent to which the presence of a child's disaster‐related physical health problem(s) have interfered with daily functioning, and family cohesion over time among Sri Lankan mothers who survived the tsunami on 26 December 2004. Study variables were measured using a self‐report questionnaire administered approximately four months after the event and three years later in summer 2008. Univariate, bivariate, and multivariate analyses were conducted. Path analysis was employed to assess the relationships between the key variables over time and the correlations in the study variables at each time point. Among other findings, the results of the path analysis indicated that post‐traumatic stress symptom distress four months after the disaster significantly predicted variance in family cohesion three years later. Clinical and empirical research implications are presented and discussed. 相似文献
133.
134.
Summary The longitudinal survivorship of a group of free-ranging male and female rhesus monkeys from La Parguera, Puerto Rico, was analyzed. Males had lower age-specific survivorship than females. There were no differences in the survivorship of daughters of high- and low-ranking mothers and there was no correlation between total number of offspring born and maternal rank for females. However, the sons of low-ranking mothers had lower survivorship than the sons of high-ranking females. This sex-related difference in survivorship, in conjunction with other evidence, indicates that the average lifetime reproduction of sons of low-ranking females is lower than that of daughters and vice versa for offspring of high-ranking females. 相似文献
135.
Douglas W. Tallamy 《Behavioral ecology and sociobiology》1985,17(4):357-362
Summary Data are presented which document that females of the subsocial lace bug, Gargaphia solani lay eggs in the nests of conspecifics whenever the opportunity arises. Because of an inverse relationship between time invested in maternal care and fecundity, maternal behavior in G. solani is an ecologically expensive trait that is adaptive only in the face of heavy predation on eggs and nymphs. By facultatively utilizing the maternal defensive behavior of conspecifics, it is possible for egg donors to protect their progeny from predators without limiting fecundity. Whenever possible, females oviposit in recently established egg masses of conspecifics. While guarding their own eggs, egg recipients inadvertently protect the eggs of egg donors. Egg donors need not establish and guard their own masses as long as there are females with egg masses in the vicinity. Instead, egg donors are free to lay as many eggs as physiologically possible by avoiding long periods of maternal care.Published with the approval of the Director of the Delaware Agricultural Experiment Station as Miscellaneous Paper No. 1048, Contribution No. 544 of the Department of Entomology and Applied Ecology, University of Delaware, Newark, Delaware, USA 相似文献
136.
Environmental fungi become a potential Indoor Air Quality (IAQ) problem when adequate moisture and nutrients are present in building materials. Because of their potential to rapidly spread contamination throughout a building, ventilation system materials are of particular significance as potential microbial contamination sources. Current recommendations are to discard fibrous glass insulation that appears to be wet or moldy. Unfortunately, this advice is not always followed. Instead, cleaning is sometimes being used in buildings to remediate fibrous glass duct liner that is already contaminated with microbial growth. The objectives of this research program were to: 1) determine, under dynamic test conditions, whether fungal spore levels on heating, ventilating, and air-conditioning (HVAC) duct material surfaces could be substantially reduced by thorough vacuum cleaning, 2) evaluate whether subsequent fungal growth could be limited or contained by mechanical cleaning, and 3) provide data concerning the advisability of cleaning duct materials. The constant high relative humidity (RH) environment to which the test materials were exposed during this study was selected as a favorable growth environment that is frequently found in Southeastern United States HVAC systems. The results showed that, following cleaning, the levels of the two test fungi, A. versicolor and P. chrysogenum, recovered to preclean levels within 6 weeks. Therefore, mechanical cleaning by contact vacuuming alone was able to only temporarily reduce the surface fungal load. The current guidelines to discard contaminated materials should be followed. 相似文献
137.
Eugene R. Masters Jack D. Riggenbach Douglas C. Ammon Richard Sobel 《补救:环境净化治理成本、技术与工艺杂志》1991,2(1):19-37
A new technique has been developed to immobilize organic chemicals at a Superfund site. In the course of predesign studies in preparing the Remedial Design for the Pioneer Sand Superfund site in Pensacola, Florida, a light, nonaqueous phase liquid (LNAPL) was discovered floating on the groundwater within the on-site landfill. The liquid, with a viscosity similar to SAE 20 motor oil, was made up of heavy organic chemicals and volatile organic chemicals (VOCs), but no pesticides or polychlorinated biphenyls (PCBs). The volatiles present included toluene, ethylbenzene, and xylenes. Regulatory agencies expressed concern over the possibility of LNAPL migration and asked that a method of LNAPL immobilization be devised. 相似文献
138.
Miki M. Stuebe Douglas M. Johnston 《Journal of the American Water Resources Association》1990,26(4):611-620
ABSTRACT: Rainfall runoff of six watersheds was modeled via the Soil Conservation Service runoff curve number model in two ways: conventionally (manually) and via a geographic information system (GIS). Input data (elevation, soils, and landcover) were digital for the latter method. In contrast to previous studies, the GIS was ised for all phases of the modeling process, including watershed delineation and routing of runoff. A comparison between the two methods was consistent with results reported by others and indicates that the use of a GIS is an acceptable alternative to the conventional method for watersheds lacking relatively flat terrain. Given this limitation, the GIS method may prove advantageous over manual methods when study areas are large or numerous, runoff is modeled repetitively, alternative landcover scenarios are explored, or a digital database already exists for the study area. 相似文献
139.
Four fetuses with a femur measuring greater than two standard deviations below the mean compared with the biparietal diameter are presented. These four fetuses were subsequently determined to have severe intrauterine growth retardation and no evidence of skeletal dysplasias. 相似文献
140.
The prenatal diagnosis of micrognathia is usually based on a subjective impression of the size of the jaw when examining the fetal profile. We have constructed a centile chart for mandibular length between 12 and 27 post-menstrual weeks in a cross-sectional study of 184 fetuses. The application of this chart in clinical practice may permit a more objective diagnosis of micrognathia in the prenatal period. 相似文献