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Kross Ethan; Duckworth Angela; Ayduk Ozlem; Tsukayama Eli; Mischel Walter 《Canadian Metallurgical Quarterly》2011,11(5):1032
Although children and adolescents vary in their chronic tendencies to adaptively versus maladaptively reflect over negative feelings, the psychological mechanisms underlying these different types of self-reflection among youngsters are unknown. We addressed this issue in the present research by examining the role that self-distancing plays in distinguishing adaptive versus maladaptive self-reflection among an ethnically and socioeconomically diverse sample of fifth-grade public schoolchildren. Children were randomly assigned to analyze their feelings surrounding a recent anger-related interpersonal experience from either a self-immersed or self-distanced perspective. They then rated their negative affect and described in writing the stream of thoughts they experienced when they analyzed their feelings. Children's stream-of-thought essays were content analyzed for the presence of recounting statements, reconstruing statements, and blame attributions. Path analyses indicated that children who analyzed their feelings from a self-distanced perspective focused significantly less on recounting the “hot,” emotionally arousing features of their memory (i.e., what happened to me?) and relatively more on reconstruing their experience. This shift in thought content—less recounting and more reconstruing—led children in the self-distanced group to blame the other person involved in their recalled experience significantly less, which in turn led them to display significantly lower levels of emotional reactivity. These findings help delineate the psychological mechanisms that distinguish adaptive versus maladaptive forms of self-reflection over anger experiences in children. Their basic findings and clinical implications are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
94.
Mirey Bonfil Ahmet Sirkecioglu Ozlem Bingol‐Ozakpinar Fikriye Uras F. Seniha Güner 《应用聚合物科学杂志》2014,131(15)
A series of polyurethane film were prepared from poly(ethylene glycol) with different molecular weight (PEG 1500, 3000, and 8000) and castor oil by one‐shot bulk polymerization method. Hexamethylene diisocyanate and 1,4‐buthane diol were used as diisocyanate and chain extender, respectively. In order to characterize the samples, their density, swelling ratio, water contact angle, surface free energy, gel content, thermal, and viscoelastic properties were determined. The effect of the soft segment length (SSL) and hard segment content (HSC) of all polyurethane films on their shape memory behavior such as shape fixity (Rf) and shape recovery (Rr) rates were investigated by bending test. Direct contact and MTT tests were used for assessment of cell adhesion and proliferation. The relatively high Rf and Rr values were obtained for the samples programmed at high temperature difference. Rf increased with decreasing HSC. On the other hand, Rr tended to decrease with increasing SSL. After evaluating experimental data by a nonlinear equation, it was found that HSC is more effective parameter on shape memory property than SSL. The gel content, swelling ratio, and water contact angle of the samples were dependent on both SSL and HSC in their structures. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40590. 相似文献
95.
Scientometrics - In 2015, a new ex-post incentive policy was introduced in Turkey to increase the academic productivity of researchers. This convergent parallel design study aims to find an answer... 相似文献
96.
Ibtissam Ressam Abdelkrim El Kadib Mohammed Lahcini Gerrit A. Luinstra Hubert Perrot Ozlem Sel 《International Journal of Hydrogen Energy》2018,43(40):18578-18591
The introduction of naturally occurring fibrillary structured halloysite clays (HNTs) into the Nafion matrix resulted in an enhanced proton conductivity and a reduced activation energy for proton transport. To assess the effect of the various states of the HNTs as a membrane additive, the σH+ of the composite membranes (Nafion/HNTs, Nafion/HNTs-NH2, Nafion/HNTs-SO3H) was measured at 30 °C and 80 °C and at different levels of relative humidity (%RH). An overall improvement of the σH+ of the Nafion was observed in the presence of the nanotubular additives (HNTs or HNTs-NH2) which can be attributed to the high specific surface area accommodating hydrophilic functional groups and therefore contributing to the water retention/management in the composite membrane. However, the Nafion/HNT-SO3H composites are distinguished in terms of enhanced performance in σH+ which persist in the whole range of % RH levels and noted that the σH+ values are almost 2 times higher than native Nafion in the low humidity region (30%–50%) and at 80 °C. In agreement with the σH+ enhancement, the activation energy is lower than that of native Nafion indicating that the proton transport is facilitated in the presence of -SO3H modified HNTs, probably due to an improved connectivity and arrangement of ionic conducting domains. 相似文献
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Various physical, chemical and genetic approaches have been applied in order to enhance enzyme stability and activity. In this study, the aim was to investigate the capability of sub- and supercritical carbon dioxide to alter the stability and activity of α-amylase as an alternative technique. The effects of operational parameters such as pressure (50-300 bar), temperature (28-80 °C), CO? flow (2-10 g min?1) and time (60-180 min) were evaluated in regard to the activity and stability of fungal based α-amylase from Aspergillus oryzea. The activity of untreated enzyme was determined as 17,726 μmol/ml/min. While both sub- and supercritical conditions enhanced the activity, the increase in flow rate had an adverse effect and the activity was decreased by 28.9% at a flow rate of 10 g min?1 under supercritical conditions. Nuclear magnetic resonance (NMR) spectra of untreated enzyme and treated samples exhibiting the lowest and the highest activities were almost identical except for the chemical shifts observed at the lowest activity sample from 4.0 to 4.4 ppm which were assigned to protons of hydrogen-bonded groups. Optimum conditions were determined as 240 bar, 41 °C, 4 g min?1 CO? flow and 150 min of process duration yielding 67.7% (29,728 μmol/ml/min) higher activity than the untreated enzyme providing fundamental basis for enzymatic applications. 相似文献
99.
In traditional wireless sensor network (WSN) applications, energy efficiency may be considered to be the most important concern whereas utilizing bandwidth and maximizing throughput are of secondary importance. However, recent applications, such as structural health monitoring, require high amounts of data to be collected at a faster rate. We present a multi-channel MAC protocol, MC-LMAC, designed with the objective of maximizing the throughput of WSNs by coordinating transmissions over multiple frequency channels. MC-LMAC takes advantage of interference and contention-free parallel transmissions on different channels. It is based on scheduled access which eases the coordination of nodes, dynamically switching their interfaces between channels and makes the protocol operate effectively with no collisions during peak traffic. Time is slotted and each node is assigned the control over a time slot to transmit on a particular channel. We analyze the performance of MC-LMAC with extensive simulations in Glomosim. MC-LMAC exhibits significant bandwidth utilization and high throughput while ensuring an energy-efficient operation. Moreover, MC-LMAC outperforms the contention-based multi-channel MMSN protocol, a cluster-based channel assignment method, and the single-channel CSMA in terms of data delivery ratio and throughput for high data rate, moderate-size networks of 100 nodes at different densities. 相似文献
100.
Slow, fast and flash pyrolysis of rapeseed 总被引:3,自引:0,他引:3
Pyrolysis experiments have been conducted on a sample of rapeseed to determine particularly the effects of pyrolysis temperature, heating rate, particle size and sweep gas flow rate on the pyrolysis product yields and their chemical compositions. The maximum oil yield of 73% was obtained at the final pyrolysis temperature of 550–600 °C, particle size range of +0.6–1.25 mm, and sweep gas flow rate of 100 cm3min−1 (N2) at flash pyrolysis conditions in tubular transport reactor. Chromatographic and spectroscopic studies on the pyrolytic oil showed that the oil obtained from rapeseed can be used as a renewable fuel and chemical feedstock. 相似文献