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51.
Acenaphthene and acenaphthylene are polycyclic aromatic hydrocarbons (PAHs) emitted into the atmosphere from a variety of incomplete combustion sources such as diesel exhaust. Both PAHs are present in the gas phase under typical atmospheric conditions and therefore can undergo atmospheric gas-phase reactions with the hydroxyl (OH) radical and for acenaphthylene with ozone. Using a relative rate method, rate constants have been measured at 296 +/- 2 K for the OH radical reactions with acenaphthene and acenaphthylene of (in units of 10(-11) cm3 molecule(-1) s(-1)) 8.0 +/- 0.4 and 12.4 +/- 0.7, respectively, and for the O3 reaction with acenaphthylene of (1.6 +/- 0.1) x 10(-16) cm3 molecule(-1) s(-1). The products of the gas-phase reactions of acenaphthene and acenaphthylene and their fully deuterated analogues have been investigated using in situ atmospheric pressure ionization tandem mass spectrometry (API-MS) and gas chromatography-mass spectrometry (GC-MS). The major products identified from the OH radical-initiated reaction of acenaphthene and acenaphthylene were a 10 carbon ring-opened product and a dialdehyde, respectively. The major product observed from the API-MS analysis of the O3 reaction with acenaphthylene was a secondary ozonide, which was not observed by GC-MS. 相似文献
52.
Pelley J 《Environmental science & technology》2002,36(23):446A-447A
53.
A model of a heavy-duty vehicle driveline with automatic transmission has been developed for estimating engine speed and load from vehicle speed. The model has been validated using emissions tests conducted on three diesel vehicles on a chassis dynamometer and then on the engines removed from the vehicles tested on an engine dynamometer. Nitrogen oxide (NOx) emissions were proportional to work done by the engine. For two of the engines, the NOx/horsepower(HP) ratio was the same on the engine and on the chassis dynamometer tests. For the third engine NOx/HP was significantly higher from the chassis test, possibly due to the use of dual engine maps. The engine certification test generated consistently less particulate matter emissions on a gram per brake horsepower-hour basis than the Heavy Duty Transient and Central Business District chassis cycles. A good linear correlation (r2 = 0.97 and 0.91) was found between rates of HP increase integrated over the test cycle and PM emissions for both the chassis and the engine tests for two of the vehicles. The model also shows how small changes in vehicle speeds can lead to a doubling of load on the engine. Additionally, the model showed that it is impossible to drive a vehicle cycle equivalent to the heavy-duty engine federal test procedure on these vehicles. 相似文献
54.
Andrew Ireland Bill J. Ellis Andrew Cook Roderick Chapman Janet Barnes 《Journal of Automated Reasoning》2006,36(4):379-410
Using automated reasoning techniques, we tackle the niche activity of proving that a program is free from run-time exceptions.
Such a property is particularly valuable in high integrity software, for example, safety- or security-critical applications.
The context for our work is the SPARK Approach for the development of high integrity software. The SPARK Approach provides
a significant degree of automation in proving exception freedom. Where this automation fails, however, the programmer is burdened
with the task of interactively constructing a proof and possibly also having to supply auxiliary program annotations. We minimize
this burden by increasing the automation, through an integration of proof planning and a program analysis oracle. We advocate
a ‘cooperative’ integration, where proof-failure analysis directly constrains the search for auxiliary program annotations.
The approach has been successfully tested on industrial data. 相似文献
55.
O'Hara Michael W.; Schlechte Janet A.; Lewis David A.; Varner Michael W. 《Canadian Metallurgical Quarterly》1991,100(1):63
Demographic, psychiatric, social, cognitive, and life stress variables were used to determine the etiology of depression in childbearing (CB; n?=?182) and nonchildbearing (NCB; n?=?179) women. Hormonal variables in postpartum depression were also evaluated. In the CB group predictors of depression diagnosis were previous depression, depression during pregnancy, and a Vulnerability (V)?×?Life Stress (LS) interaction; predictors of depressive symptomatology were previous depression, depressive symptoms during pregnancy, life events, and V?×?LS. Only estradiol was associated with postpartum depression diagnosis. In the NCB group V?×?LS was the only predictor of depression diagnosis; depressive symptoms during pregnancy and life events were predictors of depressive symptomatology. Previous findings about depression vulnerability were replicated. The significant V?×?LS interactions support the vulnerability-stress model of postpartum depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Two experiments examined young children's use of behavioral frequency information to make behavioral predictions and global personality attributions. In Experiment 1, participants heard about an actor who behaved positively or negatively toward 1 or several recipients. Generally, children did not differentiate their judgments of the actor on the basis of the amount of information provided. In Experiment 2, the actor behaved positively or negatively toward a single recipient once or repeatedly. Participants were more likely to make appropriate predictions and attributions after exposure to multiple target behaviors and with increasing age. Overall, children's performance was influenced by age-related positivity and negativity biases. These findings indicate that frequency information is important for personality judgments but that its use is affected by contextual complexity and information-processing biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Hill Clara E.; Helms Janet E.; Spiegel Sharon B.; Tichenor Victoria 《Canadian Metallurgical Quarterly》1988,35(1):27
We developed a measure of client reactions to therapist interventions. The 21 categories of the measure were divided into 14 positive and 7 negative reactions, which differed significantly from each other on client helpfulness ratings. Preliminary validity data indicated that therapist intentions were related to client reactions more for successful cases than unsuccessful cases, pretreatment symptomatology was highly predictive of which reactions the clients reported, there were some predictable changes in reactions across time in treatment, and within-case correlations of reactions with client-rated session depth and smoothness indicated some similarities across cases. We discuss the case-specific nature of client reactions, methodological issues, and the need for greater therapist awareness of client reactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Hayes Jeffrey A.; McCracken Janet E.; McClanahan Mary K.; Hill Clara E.; Harp Jennifer S.; Carozzoni Paul 《Canadian Metallurgical Quarterly》1998,45(4):468
A consensual qualitative research strategy was used to examine data from 127 interviews conducted with 8 psychologists immediately following their sessions of brief therapy with 8 clients. Analyses revealed 3 domains relevant to countertransference: origins (including categories of family issues, needs and values, therapy specific issues, and cultural issues), triggers (including categories of content of client material, therapist comparing client with others, change in therapy structure or procedures, therapist assessing progress of therapy, therapist perception of client, and emotions), and manifestations (including categories of approach, avoidance, negative feelings, and treatment planning). The frequency of categories within and across cases was classified, and relationships among categories from the 3 domains were detected, generating hypotheses for future empirical research. Implications for practice, training, and continued research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Interviewed 100 social scientists and 155 decision makers in mental health about what makes social research useful for public policy. Contrary to the expectations of the social scientists, the 2 groups evaluated research and the research-to-policy connection in much the same ways. Where there were disagreements, social scientists overestimated the role of political considerations and underestimated the role of scientific merit in decision makers' judgments of what is useful. The pattern of results suggests that the most important difference between groups lies in their notions of what it means to use research. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
This paper compares two approximation procedures with the implicit enumeration technique for solving reliability optimization problems. The integer nature of the problem is stressed and suggestions are made for evaluating future efforts to solve the problem. 相似文献