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Obstetric complications, such as severe pre-eclampsia, fetal growth restriction, abruptio placentae, or stillbirth are associated with abnormally elevated second-trimester maternal serum alpha-fetoprotein (MSAFP) and β subunit of human chorionic gonadotrophin (βhCG). This has been attributed to placental abnormalities. Women with thrombophilias have been shown to have abnormalities of the placenta resulting in adverse pregnancy outcome in these patients. The purpose of the present study was to evaluate whether women with pregnancy complications and inherited thrombophilias have abnormally elevated second-trimester MSAFP or βhCG. Sixty-two women with pregnancy complications were tested for inherited thrombophilias several months after delivery. The thrombophilia group included 29 women with pregnancy complications and an inherited thrombophilia and the control group included 33 other patients without thrombophilia. Patients in the thrombophilia group had a higher median MoM MSAFP compared to the controls (1.337 vs 1.086, p=0.0516). The incidence of abnormally elevated MSAFP (>2.5 MoM) was also significantly higher in the thrombophilia group compared to controls (21% vs 3%, p=0.04). Neither the median MoM βhCG nor the incidence of abnormally elevated βhCG were significantly different between the groups. We conclude that second trimester MSAFP, but not βhCG, is abnormally elevated in patients with thrombophilia and obstetric complications. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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This paper examined the effects of work and family stressors and conflicts on Air Force women's mental health and functioning. We analyzed data from a 1993 survey of representative stratified samples of 525 Air Force women from the active duty reserve and guard forces. The analyses of the data are guided by the comprehensive model of work–family conflict that has been tested by Frone, Russell, and Cooper (1992) using a large representative community sample. Structural equation modeling analyses provided support for the work–family conflict model. The analyses also provided support for an extension of the model, which included the separate effects of marital and parental roles on mental health. The extended model demonstrated that job and parental stresses had direct effects on work–family conflicts and that job and marital distress and family–work conflict had an independent adverse effect on mental health. Whereas job and parental involvement had a beneficial effect on distress, they had an adverse effect on work–family conflicts. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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Many states are promoting the cleanup and reuse of industrial sites. The reasons stem from the need to implement cost-effective risk reduction programs that show reasonable progress in the cleanup of contaminated sites and from the need to make effective use of industrial sites instead of abandoning them and making use of greenfield sites for new industrial facilities. The industrial land-use cleanup criteria developed by states are primarily risk-based. Several EPA regional offices also have developed similar risk-based cleanup criteria. This article addresses methodologies employed for assessing and evaluating the level of cleanup at several industrial sites in Texas, Michigan, and Ohio. This includes defining the regulatory framework, estimating the level and extent of contamination of soil and groundwater, assessing migration pathways, performing health risk assessments, and estimating cleanup requirements and associated costs. The implications associated with the various types of risk reduction options available for these states also are addressed.  相似文献   
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Self‐efficacy belief is a significant predictor of behavioral choices in terms of goal setting, the amount of effort devoted to a particular task, and actual performance. This study conceives of formation and change of self‐efficacy as a social and context‐dependent process. We hypothesized that different group factors (discretionary and ambient group stimuli) influence changes in members' self‐efficacy through differing routes (individual‐level and cross‐level processes). We tested our hypotheses using data from individuals in 169 training groups who attended a 5‐day workshop designed to increase participants' job‐search skills and efficacy. Specifically, we examined the degree of change in participants' job‐search efficacy before and after the workshop. The results showed that (a) membership diversity in education was positively related to increases in job‐search efficacy, (b) supportive leadership contributed to job‐search efficacy at the individual level of analysis with no cross‐level effects, and (c) open group climate contributed to job‐search efficacy through both individual‐level and cross‐level processes. Limitations and directions for future research are discussed. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
5.
One of the key elements in estimating the environmental effects associated with the deposition of airborne chemicals and, in particular, salt particles from cooling towers is the drift rate. Eight different experimental methods are currently employed to determine the drift rate from cooling towers. The difficulties associated with the various techniques vary from case to case, but they are mainly associated with collecting a representative sample, maintaining undisturbed air flow, determining the collection efficiency of the various sampling techniques and analyzing the samples for particle size.

Several approaches have been taken to predict the deposition of salt water drift droplets on ground surfaces. Some use a simple analogy with the deposition of industrial dust, others use a combination of plume rise theories in conjunction with the Gaussian diffusion model to predict the air concentration of water droplets from which the ground deposition is then calculated. Other methods calculate the trajectories of the drift droplets accounting for their evaporation or employ diffusion type equations. Estimates derived from the various models used to predict drift deposition appear to vary by a factor of ±10 from each other.

In contrast to the fast development in drift loss measurements, very few attempts have been made to measure actual drift deposition from fresh and salt water cooling towers and to compare experimental results with numerical models.

This paper presents a discussion on the state-of-the-art of measuring and computing drift losses. In particular, drift rate values, droplet size distribution and some typical measured and calculated ground deposition values are discussed.  相似文献   
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This article provides an overview of a dynamic methodology leading to the estimation of the level of mercury concentration in soil and soil cleanup volumes associated with a large number of gate stations suspected of having mercury in their soil. The methodology uses a unique screening approach that has been developed for relating measurements of volatile mercury near the surface to mercury concentration in the upper soil subsurface (about twelve inches deep). The screening approach was used in an effort to reduce the number of sites that are subject to extensive multimedia environmental sampling and analysis. The approach helps to focus on a small number of sites that are suspected of having the highest mercury concentration in soil, perform multimedia environmental sampling at these sites, use the field data to perform risk assessment, and determine the cleanup action levels and the volume of hot spots soil to be cleaned at these sites. The information obtained for the most contaminated sites is used to determine, if required, the level of cleanup for less contaminated sites.  相似文献   
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Employee engagement has recently been introduced as a concept advantageous to organizations. However, little is known about the value of employee engagement in explaining work performance behaviors compared with similar concepts. The learning climate, defined as the organization's beneficial activities in helping employees create, acquire, and transfer knowledge, has also been proposed as an antecedent of employee engagement. Using data from a sample of 625 employees and their supervisors in various occupations and organizations throughout Israel, we investigated employee engagement as a key mechanism for explaining the relationship between perceptions of the organization's learning climate and employees' proactivity, knowledge sharing, creativity, and adaptivity. We also tested whether employee engagement explained the relationship more thoroughly than similar concepts such as job satisfaction and job involvement. Multilevel regression analyses supported our hypotheses that employee engagement mediates the relationship between the perceived learning climate and these extra‐role behaviors. Moreover, engagement provides a more thorough explanation than job satisfaction or job involvement for these relationships. The implications for organizational theory, research, and practice are discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
10.
Conant RT  Steinweg JM  Haddix ML  Paul EA  Plante AF  Six J 《Ecology》2008,89(9):2384-2391
Soil C decomposition is sensitive to changes in temperature, and even small increases in temperature may prompt large releases of C from soils. But much of what we know about soil C responses to global change is based on short-term incubation data and model output that implicitly assumes soil C pools are composed of organic matter fractions with uniform temperature sensitivities. In contrast, kinetic theory based on chemical reactions suggests that older, more-resistant C fractions may be more temperature sensitive. Recent research on the subject is inconclusive, indicating that the temperature sensitivity of labile soil organic matter (OM) decomposition could either be greater than, less than, or equivalent to that of resistant soil OM. We incubated soils at constant temperature to deplete them of labile soil OM and then successively assessed the CO2-C efflux in response to warming. We found that the decomposition response to experimental warming early during soil incubation (when more labile C remained) was less than that later when labile C was depleted. These results suggest that the temperature sensitivity of resistant soil OM pools is greater than that for labile soil OM and that global change-driven soil C losses may be greater than previously estimated.  相似文献   
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