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61.
62.
A measure of family social support for workers was developed, and initial investigations of its psychometric characteristics were conducted. Data from several samples endorse the internal consistency of the support dimensions of emotional sustenance and instrumental assistance, and confirmatory factor analysis findings reinforce the bidimensional structure of the instrument. Lack of a relationship with social desirability, correlations with life and job satisfactions, and gender differences in perceived instrumental assistance afford preliminary validity evidence. Exploratory multiple regression analyses revealed significant three-way interactions suggesting that the level of emotional sustenance from family members may be important to job satisfaction for employed women. Furthermore, empirical evidence was generated to assess the viability of the instrument relative to other existing measures of social support. Results supported convergent, discriminant, and nomological validity.  相似文献   
63.
ABSTRACT: Streamside red alder (Alnus rubra Bong.) stands are common in western Oregon, and they have been suspected of causing water quality problems in domestic supplies during autumn leaf fall. Studies in the Seaside municipal watershed showed potential water quality effects (particularly increased color) from alder leaves, but stream sampling during 1981–82 revealed no chronic problems. The few observed short-term increases in water color occurred near the onset of storm flows, which suggested a flushing of organic matter storage sites. An extended period of unusually low flows and high leaf fall are probably necessary to produce significant water quality problems in this stream system. Laboratory leaching of alder leaves in filtered stream water indicated a fairly constant release of colored organic matter over time, and running water leached this matter more efficiently than still water. Water color increased linearly with increasing leaf mass added to still water, and for a given leaf mass there appeared to be a limit to the amount of colored matter that could be removed in the first 48 hours of leaching. Other laboratory tests showed that ultraviolet absorbance (254 mm) may provide a reasonable estimate of dissolved organic carbon concentrations in systems dominated by alder leaf inputs.  相似文献   
64.
The pattern of cadmium in the environment of five Minnesota cities   总被引:1,自引:0,他引:1  
This paper reports on the cadmium results of a soil survey conducted by the State of Minnesota during the summer of 1986. The survey collected soil-dust trom the oldest census tracts of Minneapolis, St. Paul, Duluth, St. Cloud and Rochester. The results reveal fundamental differences in soil cadmium among cities. Soil cadmium exceeds 2 g g–1 in 8.4% of the samples in Minneapolis, and 7.0, 4.0, 3.3 and 1.5% respectively of the samples collected in St. Paul, Duluth, St. Cloud and Rochester. Minneapolis and St. Paul residential houseside soil samples had cadmium levels that exceeded 2 g g–1 in 24.5 and 21.2% respectively of the samples collected. By comparison, the Minneapolis and St. Paul residential streetside soil samples had cadmium levels that exceeded 2 g g–1 in 1.2 and 0.6%, respectively, of the samples collected. Also the Minneapolis and St. Paul residential midyard soil samples had cadmium levels that exceeded 2 g g–1 in 1.9 and 5.5%, respectively, of the samples collected. Cadmium levels for the combined data for all cities and communities in Minneapolis appears to be directly related to traffic flow. However, cadmium levels around housesides and in midyards do not follow patterns of traffic flow in the same manner as cadmium content of soils along streetsides. St. Paul has an anomalously high cadmium content toward the east of the city compared with the west side of the city. The Pigs Eye sewage sludge incinerator located east of the city is the most likely source of cadmium to cause this pattern. This study provides essential urban background information about both the fundamental environmental patterns of cadmium as well as processes which appear to operate to cause those patterns.  相似文献   
65.
We explored temporal trends of young-of-year (YOY) fishes caught in bottom trawl hauls at an established offshore monitoring site in Lake Erie in fall during 1961–2001. Sampling was conducted during morning, afternoon, and night in each year. Catches per hour (CPH) of alewife (Alosa pseudoharengus) YOY were relatively low and exhibited no temporal trend. This result was consistent with the species’ intolerance to Lake Erie’s adverse winter water temperatures. Gizzard shad (Dorosoma cepedianum) YOY decreased sharply after 1991, which was consistent with recent oligotrophication of the lake. Following the establishment in 1979 and rapid increase of white perch (Morone americana) YOY, white bass (Morone chrysops) and freshwater drum (Aplodinotus grunniens) YOY decreased. Trout-perch (Percopsis omiscomaycus) YOY decreased during 1986–1991, but recovered to previous levels during 1991–2001. The recovery coincided with the resurgence of mayflies (Ephemoptera) in the lake. CPH of spottail shiner (Notropis hudsonius) and emerald shiner (N. atherinoides) YOY exhibited no temporal trend between 1961 and the late 1970s to early 1980s. CPH of yellow perch (Perca flavescens) YOY decreased during 1961–1988, and walleye (Sander vitreum) YOY increased overall during the time series. These observations were consistent with published studies of adults in the region. CPH of 4 of the 10 species of YOY considered were greatest during night. CPH for walleye YOY was higher in the morning than in the afternoon, but there was no significant difference between night and morning abundances. The results suggest that (1) CPH of YOY fishes may be a useful monitoring tool for Lake Erie, and (2) offshore monitoring programs that do not include night sampling periods may underestimate recruitment for several common species.  相似文献   
66.
Indoor and ambient concentrations of 21 volatile organic compounds (including 14 hazardous air pollutants) were measured in the homes of nearly 80 western Montana (Missoula) high school students as part of the 'Air Toxics Under the Big Sky' program during the 2004/2005 and 2005/2006 school years. Target analytes were measured using low flow air sampling pumps and sorbent tubes, with analysis of the exposed samples by thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS). The results reported here present the findings of the first indoor/ambient air toxics monitoring program conducted in a semi-rural valley location located in the Northern Rocky Mountain/Western Montana region. Of all of the air toxics quantified in this study, toluene was found to be the most abundant compound in both the indoor and ambient environments during each of the two school years. Indoor log-transformed mean concentrations were found to be higher when compared with ambient log-transformed mean concentrations at P < 0.001 for the majority of the compounds, supporting the results of previous studies conducted in urban areas. For the air toxics consistently measured throughout this program, concentrations were approximately six times higher inside the student's homes compared to those simultaneously measured directly outside their homes. For the majority of the compounds, there were no significant correlations between indoor and ambient concentrations.  相似文献   
67.
Climate change and biodiversity loss have a central position in policy debate about global environmental change; however, of the two, climate change has a higher profile. This paper explores the similarities and difference between the two issues. Climate change is better defined and better understood as a policy issue, it is underpinned by a strong scientific consensus and practical units of measurement (CO2 and financial impacts), and mitigation involves a key economic sector in energy. Biodiversity loss is less easily understood, more diffuse and less tangible, and policy responses do not engage major economic sectors. We argue that these differences contribute to the higher public and policy profile of climate change and can inform attempts to enhance responses to the problem of biodiversity loss.  相似文献   
68.
The extensive application of 2,4-D herbicides to wheat and other agricultural crops in the states of Washington and Oregon can produce "off-target" damage when the 2,4-D formulations are transported by the atmosphere to sensitive crops, such as grapes. During May-June of 1973 and April-June of 1974, a 2,4-D monitoring network in south-central Washington collected samples for subsequent herbicide analysis. The daily, 24 hr field samples were collected with differential Impactor-impinger air samplers and were routinely analyzed in the analytical laboratory by electron-capture gas chromatography. In addition, gas chromatography/mass spec-trometry was employed for positive identification of the 2,4-D esters and for comparative quantitative analysis. The complete sampling and analytical methodology, the 2,4-D concentration data for 1973 and 1974, the agricultural 2,4-D application records and crop Injury reports, and the concomitant meteorological data are described in this paper.  相似文献   
69.
Emission factors for particulate matter and carbon monoxide have been measured for wood, anthracite coal, and bituminous coal burned in residential heaters operated at less than 15 kW (50,000 Btu/hr). In these studies the stove effluent is mixed with about four volumes of outside air and samples are collected about two minutes after mixing. The main purpose of using this sampling method is to simulate atmospheric conditions more closely. Particulate samples are collected on 20 × 25 cm filters after cyclone preseparation of particles larger than 4 μm. Carbon monoxide concentrations are measured with Draeger tubes.

Particulate emission factors for wood ranged from 1.6 to 6.4 g/kg (fuel) and were found to depend on the fuel load and the firing rate, as indicated by earlier studies. These values are substantially less than the values obtained previously for stoves operated under similar conditions. The average particulate emission factors for bituminous and anthracite coal are 10.4 and 0.50 g/kg, respectively. Carbon monoxide emission factors for wood, bituminous, and anthracite coal are 100,116, and 21 g/kg, respectively.  相似文献   
70.
Editor’s note: Donald F. Adams was Past President of the Air Pollution Control Association in 1983 when he led a delegation of air quality experts to the People’s Republic of China for a technical information exchange. Professor Adams has provided an informative (and humorous) report of this technical exchange and we are pleased to share it with the readers of JAPCA.  相似文献   
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