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991.
Michael J. Hawkins Bernard P. Hyde Michael Ryan R. P. O. Schulte John Connolly 《Nutrient Cycling in Agroecosystems》2007,79(1):93-101
This paper describes an empirical model of soil-evolved nitrous oxide emissions inferred from data gathered in a 2-year rotational
grazing experiment investigating emissions from a fertilised and grazed grassland site. The model was used to simulate daily
and annual emissions for the 9-year period between 1994 and 2002 under different possible fertiliser application scenarios.
As the model only requires a small number of commonly available site-specific data inputs, this facilitates its use at different
geographical locations. This is the first empirical modelling of daily fluxes to give estimates of annual emissions. Results
reveal a high interannual variability of emissions that increases with the amount of nitrogen fertiliser applied. Simulation
using the model for the period 1994–2002 indicated that higher soil moisture status on the day of fertiliser N application
increased the average annual nitrous oxide emissions. 相似文献
992.
Roland Hany René Hartmann Christine Böhlen Jumpei Kawada Christiane Löwe Bernard Witholt 《Polymer》2005,46(14):5025-5031
A polyhedral oligomeric silsesquioxane containing seven isobutyl groups and one mercaptopropyl group (POSS-SH) was linked via a free radical addition reaction to the side-chain double bonds of bacterial poly[3-hydroxyalkanoate-co-3-hydroxyalkenoate], (PHAE). PHAE with 11.5, 55, 78, and 97 mol% of double bonds were used to produce a series of inorganic-organic hybrid materials, PHAE-POSS, with increasing amounts of POSS. The reactions proceeded with high yields and limited side reactions, confirmed with NMR and GPC experiments. X-ray diffraction and 13C solid-state NMR analysis of these nanocomposite materials suggested the favoured crystallization of POSS, with PHAE functioning as a non-crystalline combining matrix. This is in contrast to blends of POSS-SH and PHAE, where incompatibility occurred and the two components crystallized independently. The covalent links between PHAE and POSS imposed spatial constraint which resulted in disordered crystalline POSS domains and limited crystal sizes. With increasing POSS content, the appearance of these POSS-based biopolyesters changed from non-sticky and elastic to brittle and glass-like. The covalent linking of POSS-SH to PHAE increased the heat stability such as glass transitions, and melting points could be tailored between 48 and 120 °C. 相似文献
993.
Nathalie Nallet Marlène Bernard Mireille Chiron 《Accident; analysis and prevention》2008,40(6):1836-1843
This paper sets out to describe the drivers attending driving licence points recovery courses (PRC), in order to modify the psychologist’s approach during the sessions.The paper describes a questionnaire-based survey of a representative sample of 853 drivers taking a “course designed to raise awareness about the causes and consequences of road traffic accidents”. The data are analyzed in part by applying a multiple correspondence analysis.Among those taking part in PRC, recognizing whether they commit violations or not seems to be independent from the perceived probability of sanctioning and the perceived danger. The group of course-takers is divided into two main clusters (“offenders” and “victims”) which require a completely different approach on the part of the training staff. 相似文献
994.
Three studies are presented on attention paid to feedback provided by a computer-based assessment for learning on information literacy. Results show that the attention paid to feedback varies greatly. In general the attention focuses on feedback of incorrectly answered questions. In each study approximately fifty percent of the respondents paid attention to feedback of incorrect answers only. Approximately another twenty-five percent did not pay attention to feedback at all. Results suggest that differences in attention paid to feedback are influenced by task difficulty and test length. Supervision, however, does not seem to influence the average attention paid to feedback. On the other hand, results show that indirect and direct supervision lead to a greater impact of feedback provided by a computer-based assessment for learning as the number increases of students taking the test and, as a consequence, paying attention to feedback. 相似文献
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996.
997.
Burhans Lauren B.; Smith-Bell Carrie; Schreurs Bernard G. 《Canadian Metallurgical Quarterly》2008,122(6):1191
Interest in classical conditioning is usually focused on anticipatory responses to a stimulus associated with a significant event, and it is assumed that responses to the event itself are reflexive, involuntary, and relatively invariant. However, there is compelling evidence that both the rabbit nictitating membrane response (NMR) and heart rate response (HR), well-known reflexive reactions to aversive events, can change quite dramatically as a function of learning when measured in the absence of the conditioned stimulus. In the case of NMR conditioning, a simple blink is transformed into a larger and more complex response. For HR conditioning, reflexive heart rate acceleration can actually change to heart rate deceleration. In both cases, the reflex comes to resemble the conditioned response and follows some of the same behavioral laws. This change in response to the aversive event itself or weaker forms of that event is called conditioning-specific reflex modification (CRM). CRM may force us to reevaluate the behavioral and neural consequences of classical conditioning and may have important consequences for the treatment of conditions such as posttraumatic stress disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
PAYA Bernard GAGNOUD Annie MAUSSION Pascal ROEHR Philippe BREVILLE Thierry NEMER Maroun GOUPIL Christophe 《钢铁研究学报(英文版)》2012,(Z2):646-652
The Energy Climate Package is the EU response to the Global Warming Challenge.Induction heating processes can contribute to the energy saving goal:20%saving within 2020.European induction manufacturer already propose many efficient solutions at industrial scale.To improve induction devices for an always better energy efficiency,EDF R&D set up a French cooperative project called ISIS with a financial support of the French National Research Agency.Its objective is to promote induction heating as Best Available Technology(BAT)and to develop innovative solutions to increase its efficiency.The ISIS innovations concern the electroheat conversion of induction devices(auto-adaptive multi-coil power supply,low losses coils)and the recovering of fatally lost energy.This paper shows the mid-term results of this project.Firsts control algorithms were successfully tested on a 100 kW 3-coil power supply.A homogenization technique is proposed to model a multi-strand coil.A heat recovery test bench is build and equipped with a PFC control loop to fit with the production fluctuations. 相似文献
1000.
In 2006, Hydro-Québec introduced a large DSM program on the market to promote the adoption of compact fluorescent lamps in
Québec households. After 3 years of program implementation, there was significant indication on the part of market actors
that the promotional campaign component was quite effective in transforming the Québec market. Hydro-Québec therefore decided
to modify its approach to program evaluation to include the quantification of market effects. Econoler led a team including
American partners, Opinion Dynamics Inc. and Megdal & Associates to conduct an evaluation of program impacts on market transformation.
An evaluation strategy was designed where different research tools would be integrated to determine market evolution over
the two previous years. Each research method was used to determine an estimate of program impacts, then triangulated with
other approaches to determine the most appropriate impact evaluation method regarding the Hydro-Québec program. Research efforts
included a non-participant survey, interviews at manufacturer headquarters across Canada, interviews with banner distributor
representatives across Canada, the collection of sales and market share data from manufacturers and retailers as well as secondary
research to identify other players that could influence the market. The evaluation revealed that savings of 168 GWh could
be attributed to direct and indirect impacts of the program for the 2006–2007 period. 相似文献