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61.
62.
This study examined the environmental impact of low-complexity electrical consumer products during their use in a domestic context. In the experimental scenario, 48 users were asked to use a kettle under different conditions. On-product information (OPI), task instruction, and kettle design were employed as independent variables in a mixed multi-factorial design to examine their effects on different parameters of ecological performance (e.g., water and electricity consumption). Measures of user variables (environmental concern, knowledge, domestic habits, environmental control beliefs) were also taken to examine their relationship with performance parameters. The results revealed main effects of ecological task instruction, OPI and (partly) kettle design on ecological user behaviour. Habits, environmental concern and control beliefs were found to be related to performance parameters whereas knowledge was not. The implications of the results for product design are discussed against the background of a strong prevalence of habits and low ecological user motivation. 相似文献
63.
The study examines the cognitive demands of collision avoidance under a range of maritime scenarios. Operators used a PC-based radar simulator to navigate set courses over 100 6-min trials varying in collision threat and traffic density. Corrective maneuvers were made through the application of standard navigation rules and by using two decision aids (target acquisition and test maneuver). Results showed widespread effects of collision threat in terms of decision aid use, subjective workload, and secondary task performance. Most notably, demand increased markedly over the course of emergency trials, in which collision threat resulted from rule violation by target vessels. The findings are discussed in terms of the comparison between predictable demands (requiring standard course changes) and those involving uncertainty about the others' intentions (involving more intensive monitoring and forced delays in corrective action). The study has relevance for the design of collision avoidance systems, specifically for the use of ecological displays. 相似文献
64.
A versatile spectroelectrochemical apparatus is introduced to study the changes in IR spectra of organic and inorganic compounds upon oxidation or reduction. The design is based on an attenuated total reflection device, which permits the study of a wide spectral range of 16,700 (600 nm)-250 cm(-1), with a small opaque region of 2250-1900 cm(-1). In addition, an IR data collection protocol is introduced to deal with electrochemically nonreversible background signals. This method is tested with ferrocene in acetonitrile; concentrations as low as 1 mM produce results that agree with those in the literature. 相似文献
65.
Lueftner T. Berthold J. Pacha C. Georgakos G. Sauzon G. Hoemke O. Beshenar J. Mahrla P. Just K. Hober P. Henzler S. Schmitt-Landsiedel D. Yakovleff A. Klein A. Knight R. J. Acharya P. Bonnardot A. Buch S. Sauer M. 《Solid-State Circuits, IEEE Journal of》2007,42(1):134-144
To meet the widely varying speed and power requirements of multifunctional mobile devices, an appropriate combination of technology features, circuit-level low-power techniques, and system architecture is implemented in a GSM/Edge baseband processor with multimedia and mixed-signal extensions. Power reduction techniques and performance requirements are derived from an analysis of relevant use cases and applications. The 44 mm2 baseband processor is fabricated in a 90-nm low-power CMOS technology with triple-well option and dual-gate oxide core devices. The ARM926 core achieves a maximum clock frequency of 380 MHz at 1.4-V supply due to the usage of thin oxide (1.6 nm) devices. Power dissipation can be adapted to the performance requirements by means of combined voltage and frequency scaling to reduce active power consumption in medium-performance mode by 68%. To reduce leakage currents during standby mode, large SRAM blocks, nFET sleep transistors, and circuit components with relaxed performance requirements are implemented using devices with 2.2-nm gate oxide thickness 相似文献
66.
We show that the rod-shaped Tobacco mosaic virus (TMV) can be coated with the wide band gap semiconductor zinc oxide by electroless deposition under mild reaction conditions. The process involves pretreatment with aqueous Pd(II), followed by nucleation of ZnO, directed to palladium centers formed on the surface of TMV. The mechanism is based on the local pH change due to the reduction of nitrate by dimethylamine borane at the palladium. Morphology and chemical composition have been analyzed by transmission electron microscopy (TEM) and by energy filtering TEM, respectively. The optical properties were elucidated by cathodoluminescence, which showed the desired near-band edge emission. 相似文献
67.
68.
John K. G. Kramer Frank D. Sauer Edward R. Farnworth Dan Stevenson Gail A. Rock 《Lipids》1998,33(1):1-10
Canola oil is not presently permitted in infant formulations in the United States because of lack of information concenring
the effects of feeding canola oil to the newborn. We have previously reported a transient decrease in platelet counts and
an increase in platelet size in newborn piglets fed canola oil for 4 wk, and have confirmed this in the present study. In
canola oil-fed piglets, changes in platelet size and number were overcome by adding either long-chain saturated fatty acids
from cocoa butter (16:0 and 18:0), or shorter-chain saturates from coconut oil (12:0 and 14:0). Feeding a high erucic acid
rapeseed (HEAR) oil, with 20% 22:1n−9, led to an even greater platelet reduction and increased platelet size throughout the
4-wk trial. Bleeding times were longer in piglets fed canola oil or HEAR oil compared to sow-reared and soybean oil-fed piglets.
There were no other diet-related changes. Diet-induced platelet changes were not related to platelet lipid class composition,
but there were fatty acid changes. The incorporation of 22:1n−9 into platelet phospholipids of piglets fed canola oil was
low (0.2–1.2%), and even for the HEAR oil group ranged from only 0.2% in phosphatidylinositol to 2.4% in phosphatidylserine.
A much greater change was observed in the concentration of 24:1n−9 and in the 24:1n−9/24:0 ratio in platelet sphingomyelin
(SM). The 24:1n−9 increased to 49% in the HEAR oil group compared to about 12% in animals fed the control diets (sow-reared
piglets and soybean oil-fed group), while the 24:1n−9/24:0 ratio increased from about 1 to 12. Even feeding canola oil, prepared
to contain 2% 22:1n−9, led to a marked increase in 24:1n−9 to 29% and had a 24:1n−9/24:0 ratio of 5. The canola oil/cocoa
butter group, which also contained 2% 22:1n−9, showed a lower level of 24:1n−9 (20%) and the 24:1n−9/24:0 ratio (3) compared
to the canola oil group. The results suggest that the diet-related platelet changes in newborn piglets may be related to an
increase in 24:1n−9 in platelet SM, resulting from chain elongation of 22:1n−9. The inclusion of canola oil as the sole source
of fat in the milk-replacer diets of newborn piglets resulted in significant platelet and lipid changes. 相似文献
69.
Islam M.N. Sunderman E.R. Soccolich C.E. Bar-Joseph I. Sauer N. Chang T.Y. Miller B.I. 《Quantum Electronics, IEEE Journal of》1989,25(12):2454-2463
Using multiple-quantum-well (MQW) saturable absorbers, a NaCl color center was passively mode locked to produce 275-fs transform-limited, pedestal-free pulses with a peak power as high as 3.7 kW. The pulses are tunable from λ=1.59 to 1.7 μm by choosing MQWs with different bandgaps. The output pulses from the laser were shortened to 25 fs using the technique of soliton compression in a fiber. The steady-state operation of the laser requires the combination of a fast saturable absorber and gain saturation 相似文献
70.
We examined relationships between depressive rumination, anger rumination, and features of borderline personality disorder in a sample of 93 students with a wide range of borderline symptoms. All completed self-report measures of borderline features; trait-level negative affect; depressive and anger rumination; and current symptoms of depression, anxiety, and stress. Depressive and anger rumination were strongly associated with borderline features after controlling for comorbid symptoms of depression, anxiety, and stress. Both types of rumination showed significant incremental validity over trait-level sadness, anger, and general negative affect in predicting borderline features. Relationships with borderline features were stronger for anger rumination than for depressive rumination. Relationships between trait-level negative affect and borderline features were substantially reduced when anger rumination was included in regression models, suggesting the need for longitudinal analyses of mediation. Findings suggest that severity of borderline symptoms is influenced by ruminative thinking in response to negative affect, especially anger. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献