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81.
A High‐Performance Recycling Solution for Polystyrene Achieved by the Synthesis of Renewable Poly(thioether) Networks Derived from d‐Limonene 下载免费PDF全文
82.
Dinero Rachel E.; Conger Rand D.; Shaver Phillip R.; Widaman Keith F.; Larsen-Rife Dannelle 《Canadian Metallurgical Quarterly》2008,22(4):622
According to attachment theory, attachment style derives from social experiences throughout the life span. The authors tested this expectation by examining associations between the quality of observed interaction patterns in the family of origin during adolescence and self-reported romantic attachment style and observed romantic relationship behaviors in adulthood (ages 25 and 27). Family and romantic relationship interactions were rated by trained observers from video recordings of structured conversation tasks. Attachment style was assessed with items from D. W. Griffin and K. Bartholomew's (1994a) Relationship Scales Questionnaire. Observational ratings of warmth and sensitivity in family interactions were positively related to similar behaviors by romantic partners and to attachment security. In addition, romantic interactions characterized by high warmth and low hostility at age 25 predicted greater attachment security at 27, after controlling for attachment security at age 25. However, attachment security at age 25 did not predict later romantic relationship interactions after controlling for earlier interactions. These findings underscore the importance of close relationships in the development of romantic attachment security but do not indicate that attachment security predicts the quality of interactions in romantic relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Irene M. C. Lo Chester S. C. Lam Keith C. K. Lai 《Canadian Metallurgical Quarterly》2005,131(11):1598-1606
Eleven columns were set up under various groundwater geochemistry conditions to investigate the competitive effect of trichloroethylene (TCE) on hexavalent chromium [Cr(VI)] removal by zero-valent iron (Fe0). They were found to be electron competitors in the redox reactions. In the presence of TCE, the Cr(VI) removal capacities of Fe0 were decreased by about 40% when compared with their respective Cr(VI) removal capacities with identical groundwater geochemistry but without TCE. The specific reaction rate constant (kSA) of TCE was decreased by about 50% when Cr(VI) was singly applied. The kSA of TCE was further decreased by 75% in the presence of both Cr(VI) and carbonate. However, there was no apparent effect on the kSA of TCE when Cr(VI), hardness and carbonate were all present. It revealed that TCE was a stronger electron competitor of Cr(VI) and the degradation of TCE became more favorable when both hardness and carbonate were present. This suggests that the passivated precipitates formed on the Fe0 surface in the presence of both hardness and carbonate may significantly affect the Cr(VI) removal by Fe0 but has insignificant effect on the TCE removal. 相似文献
84.
Explored developmental patterns of gender traditionality and flexibility in 479 Ss across middle childhood and early and late adolescence and assessed the correlates of gender flexibility at these 3 developmental periods. Gender flexibility was differentiated into 2 dependent variables: self-related gender preferences and attitudes toward others. Varying theoretical developmental trends have been posited with regard to gender flexibility, but relationships obtained between age and gender flexibility were mostly positive. Several negative relationships, however, underscored the complexity of gender-related responses. Most variables assessed contributed significantly and cumulatively to the prediction of gender flexibility; socialization variables proved to be the strongest predictors of all 3 developmental levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Finkel Eli J.; Campbell W. Keith; Brunell Amy B.; Dalton Amy N.; Scarbeck Sarah J.; Chartrand Tanya L. 《Canadian Metallurgical Quarterly》2006,91(3):456
Tasks requiring interpersonal coordination permeate all spheres of life. Although social coordination is sometimes efficient and effortless (low maintenance), at other times it is inefficient and effortful (high maintenance). Across 5 studies, participants experienced either a high- or a low-maintenance interaction with a confederate before engaging in an individual-level task requiring self-regulation. Self-regulation was operationalized with measures of (a) preferences for a challenging task with high reward potential over an easy task with low reward potential (Study 1) and (b) task performance (anagram performance in Study 1, Graduate Record Exam performance in Studies 2 and 3, physical stamina in Study 4, and fine motor control in Study 5). Results uniformly supported the hypothesis that experiencing high-maintenance interaction impairs one's self-regulatory success on subsequent, unrelated tasks. These effects were not mediated through participants' conscious processes and emerged even with a nonconscious manipulation of high-maintenance interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Taylor H. Gerry; Dietrich Ann; Nuss Kathryn; Wright Martha; Rusin Jerome; Bangert Barbara; Minich Nori; Yeates Keith Owen 《Canadian Metallurgical Quarterly》2010,24(2):148
To investigate postconcussive symptoms (PCS) following pediatric mild traumatic brain injury (mTBI), 8- to 15-year-old children with mTBI (n = 186) and a comparison group with uncomplicated orthopedic injuries (OI, n = 99) were recruited from two emergency departments. Parent and child ratings of PCS and symptom counts were obtained within 3 weeks after injury (baseline) and at 1, 3, and 12 months postinjury. The mTBI group also completed magnetic resonance imaging at baseline. Group differences were examined using growth modeling, controlling for age at injury, sex, socioeconomic status, and (for parent-based measures) preinjury symptom levels. Relative to the OI group, the mTBI group had higher ratings of somatic PCS and parent counts of PCS at the initial assessments, but higher parent ratings of cognitive PCS and child counts of PCS throughout follow-up. Higher levels of PCS in the mTBI group were associated with motor-vehicle-related trauma, loss of consciousness, neuroimaging abnormalities, and hospitalization. The findings validate both transient and persistent PCS in children with mTBI and document associations of symptoms with injury and noninjury factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Smoke gas analysis by Fourier transform infrared spectroscopy – summary of the SAFIR project results
Tuula Hakkarainen Esko Mikkola Jan Laperre Francis Gensous Peter Fardell Yannick Le Tallec Claudio Baiocchi Keith Paul Margaret Simonson Caroline Deleu Edwin Metcalfe 《火与材料》2000,24(2):101-112
The determination of toxic components from fire gases is difficult because the environment is hot, reactions are often temperature dependent, and a lot of soot may be produced. Due to the different properties of the gas components, a different time‐consuming procedure for each species has traditionally been used. The use of FTIR (Fourier transform infrared) spectrometers as a continuous monitoring technique overcomes many of the problems in smoke gas analyses. FTIR offers an opportunity to set up a calibration and prediction method for each gas showing a characteristic spectral band in the infrared region of the spectrum. The objective of the SAFIR project was to further develop the FTIR gas analysis of smoke gases to be an applicable and reliable method for the determination of toxic components in combustion gases related to fire test conditions. The optimum probe design, filter parameters and the most suitable sampling lines in terms of flow rate, diameter, construction material and operating temperature have been specified. In the large scale, special concern was given to the probe design and the effects of the probe location as well as practical considerations of the sampling line length. Quantitative calibration and prediction methods have been constructed for different components present in smoke gases. Recommendations on how to deal with interferents, non‐linearities and outliers have been provided and a verification method for the spectrometer for unexpected variations and for the different models have been described. FTIR measurement procedures in different fire test scenarios have been studied using the recommendations of this project for measurement techniques and analysis and an interlaboratory trial of the FTIR technique in smoke gas analysis was carried out to define the repeatability and reproducibility of the method in connection with a small scale fire test method, the cone calorimeter. Copyright © 2000 John Wiley & Sons Ltd. 相似文献
88.
Keith Scott 《Electrochimica acta》1983,28(2):133-140
A mathematical model is used to predict current and potential distributions in electrochemical cell banks consisting of bipolar connected parallel plate electrodes. It is shown that the adoption of bipolar connection rather than monopolar connection alleviates the problems of a maldistribution of potential caused by limitations in electrode conductivity for a majority of cells in large cell banks. However, for the outer cells potential distribution is still not uniform regardless of the number of cells in the bank. 相似文献
89.
Keith D. Bartle Michael J. Mulligan Norman Taylor Terence G. Martin Colin E. Snape 《Fuel》1984,63(11):1556-1560
A number of procedures have been investigated for the calibration of a size-exclusion chromatography (s.e.c.) column in the determination of molecular mass (MM) distributions of coal derivatives. The behaviour of narrow fractions of coal extracts in the MM range 200–3000 was compared with a variety of the more generally available calibration standards. Calibration with preparative s.e.c. subfractions of materials similar to those under study has been recommended. Polystyrene standards are satisfactory, however, for MM < 1000, but above this range other polymer standards should be sought. Universal and molar volume calibration do not apply to coal-derived materials. 相似文献
90.
Van Geest JL Mackay D Poirier DG Sibley PK Solomon KR 《Environmental science & technology》2011,45(16):7011-7018
As laboratory-based bioaccumulation methods are standardized and expanded to include other test species, kinetic studies assessing the major classes of contaminants with these species are needed to adequately select the standard duration for bioaccumulation tests. In the present study we measured the uptake (28-d exposure) of polychlorinated biphenyls (PCBs; total and selected congeners) from field-contaminated sediment in the oligochaete Lumbriculus variegatus, mayfly nymph Hexagenia spp., and fathead minnow Pimephales promelas. Depuration (25 d) of PCBs was measured in organisms that had been transferred to clean sediment after the 28-d exposure. Uptake and elimination of PCBs was rapid in L. variegatus and Hexagenia spp. Tissue residues reached steady-state concentrations within 28 d; elimination rates and biota-sediment accumulation factors (BSAFs) of the PCB congeners were not correlated with K(OW). Uptake and elimination rates of PCBs were slower in P. promelas, and it is not clear whether steady-state was reached in fish tissues. Elimination rates of the PCB congeners significantly decreased with increasing K(OW) in fish. The appropriateness of a 28-d exposure for measuring steady-state concentrations in tissue of the invertebrates was confirmed, but further study is required for fish. 相似文献