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1.
In view of the importance for CoxOy,-MoO3/-Al2O3 hydrodesulphurization (HDS) catalysts, the reactivity of cobalt oxide layers towards cobalt aluminate formation was investigated on both MoO3-covered and bare -Al2O3 substrates. Co3O4/MoO3/-Al2O3 and Co3O4/-Al2O3 systems were prepared by vapour-deposition of MoO3 (12 × 1015 Mo atoms/cm2) and Co (400 × 1015 Co atoms/cm2) layers onto a -Al2O3 substrate, followed by oxidation of the Co layer to Co3O4. After annealing at 800°C for 40 h, the interfacial reaction to cobalt aluminate was assessed using Rutherford backscattering spectrometry. The presence of molybdenum oxide appeared to enhance cobalt aluminate formation. The Mo atoms, which spread out over the entire cobalt-containing layer, presumably caused a high defect density, which explains the observed higher reaction rate. The amount of MoO3 was much too low to stabilize all cobalt atoms by cobalt molybdate formation.  相似文献   
2.
Over the past decade process mining has emerged as a new analytical discipline able to answer a variety of questions based on event data. Event logs have a very particular structure; events have timestamps, refer to activities and resources, and need to be correlated to form process instances. Process mining results tend to be very different from classical data mining results, e.g., process discovery may yield end-to-end process models capturing different perspectives rather than decision trees or frequent patterns. A process-mining tool like ProM provides hundreds of different process mining techniques ranging from discovery and conformance checking to filtering and prediction. Typically, a combination of techniques is needed and, for every step, there are different techniques that may be very sensitive to parameter settings. Moreover, event logs may be huge and may need to be decomposed and distributed for analysis. These aspects make it very cumbersome to analyze event logs manually. Process mining should be repeatable and automated. Therefore, we propose a framework to support the analysis of process mining workflows. Existing scientific workflow systems and data mining tools are not tailored towards process mining and the artifacts used for analysis (process models and event logs). This paper structures the basic building blocks needed for process mining and describes various analysis scenarios. Based on these requirements we implemented RapidProM, a tool supporting scientific workflows for process mining. Examples illustrating the different scenarios are provided to show the feasibility of the approach.  相似文献   
3.
To study the influence of steam on the solid state reaction between MeO (Me = Ni, Co, Cu or Fe) and Al2O3, MeO/-Al2O3 and MeO/-Al2O3 model catalysts were kept in either N2/20% O2 or N2/O2/30% H2O at 500–1000°C. The samples were subsequently analyzed with RBS and FTIR. Surprisingly, nickel, cobalt and copper volatilized when MeO/-Al2O3 or MeAl2U4/-Al2O3 samples were annealed in the presence of 0.3 atm steam at 1000°C. Especially copper was found to volatilize very rapidly in the presence of steam, even at a temperature as low as 800°C. FTIR spectra of steam-treated NiO/-Al2O3 samples showed the incorporation of hydroxyl groups in the nickel oxide layer. This observation and an excellent agreement with thermochemical calculations support our conclusion that the volatile species are metal hydroxides. The solid state reaction of MeO with-Al2O3 was found to proceed at a much higher rate in the presence of 0.3 atm steam at 500–800°C, presumably as a result of an enhanced surface mobility of Me and Al ions along the grain boundaries and the surfaces of the internal pores of the-Al2O3 support, when steam is present.  相似文献   
4.
Surface quality and downstream processability of hot rolled strip depend on tertiary scale thickness and composition at all process stages, from secondary descaling to the cold coil. TGA oxidation experiments provided the basis for quantitative modelling of scale growth during finishing hot rolling of low carbon steels (with or without Si or P). Finishing temperature (FT), gauge, and (particularly at the edges) coiling temperature (CT) are the main influence factors with respect to scale thickness. Based on HTXRD oxidation trials and microscopic analyses, trendlines are presented that roughly predict the final scale composition as a function of CT, for the coil centre and the edges. It appears that a CT of 400‐600°C, in combination with a coil centre position, is favourable for decomposed wustite, which is the preferred component for a good scale ad‐ and cohesion. Retention of wustite, the most preferred phase in the roll bite but very brittle at room temperature, is promoted by relatively high CTs (particularly with a coil quench) and by very low CTs. Hematite is formed at the edges in case of a high CT. This extremely hard phase is unwanted at any stage.  相似文献   
5.
Autonomy-supportive teachers: How they teach and motivate students.   总被引:2,自引:0,他引:2  
The authors examined motivating style in terms of a teacher's disposition to control students or support their autonomy. In Study 1, 4 independent samples of preservice teachers completed the Problems in Schools (PS) questionnaire so the authors could critically evaluate the instrument to assess motivating style as an individual difference characteristic. In Study 2, preservice teachers taught a 10-min instructional episode as raters judged their language and style. In Study 3, elementary and high school teachers self-reported a recent attempt to teach and motivate one of their students. Compared with their controlling counterparts, autonomy-supportive teachers showed a distinctive motivating style as measured by their conversational behaviors, interpersonal style, and attempts to support students' intrinsic motivational and internalization processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The dependence construct fills an important explanatory role in motivational accounts of smoking and relapse. Frequently used measures of dependence are either atheoretical or grounded in a unidimensional model of physical dependence. This research creates a multidimensional measure of dependence that is based on theoretically grounded motives for drug use and is intended to reflect mechanisms underlying dependence. Data collected from a large sample of smokers (N = 775) indicated that all 13 subscales of the Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) have acceptable internal consistency, are differentially present across levels of smoking heaviness, and have a multidimensional structure. Validity analyses indicated the WISDM-68 subscales are significantly related to dependence criteria such as smoking heaviness and to 4th edition Diagnostic and Statistical Manual of Mental Disorders symptoms of dependence and relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
INTRODUCTION: Ten years of publications (1984-1993) about drug compliance in spanish hypertensive patients are presented. MATERIAL AND METHODS: A bibliography search of Medline (EBSCO CD-ROM ver 104.1, act Jul 1995), Indice Médico Espa?ol (CSIC CD-ROM, act Oct 1993) and other sources has been made. RESULTS: 39 articles have been located and 23 investigational publications have been analysed. All the publications, but one, have evaluated the compliance by an indirect method, mainly patient selfdeclaration. The degree of patient compliance determined by interviews, questionnaires or inquiries is 55.5% (IC 95%: 52.7-58.3). The patient compliance in the publications that use methods based in pill counts is 46.4% (IC 95%: 41.6-51.2). The treatment dropout is present in the 18.5% of the patients (IC 95%: 20.5-16.5). CONCLUSIONS: The drug compliance degree in Spanish patients with hypertension is low.  相似文献   
8.
Multiparous Holstein cows (n = 18) were fed a total mixed ration containing corn silage, corn grain, whole cottonseed, soybean meal, dried distillers grains, and chopped bermudagrass hay (control) or same diet plus Ca salts of long-chain fatty acids (2.2% of diet DM) for the first 60 d postpartum. Predicted energy balance was calculated from DM intake, milk yield and composition, and BW. On d 25 postpartum, cows were injected with 25 mg of prostaglandin F2 alpha and treated for 15 d with an intravaginal device containing 1.9 g progesterone. Profiles of 15-keto-13,14-dihydro-prostaglandin F2 alpha (d 1 to 21) and plasma triglycerides (d 7 to 60) were similar between groups. Average number of follicles, determined by ultrasonography prior to d 25, tended to differ between groups; controls had more 3- to 5-mm and fewer 6- to 9-mm follicles than the group of fat-fed cows. Basal, smoothed mean concentration, and average luteinizing hormone amplitude, determined by 10-min samples for 8 h on d 10, were not significantly different between groups. Increasing predicted energy balance was associated with increased pulse amplitude and diameter of the largest follicle on d 10. During the progesterone treatment period and the postprogesterone treatment estrous cycle, cows fed fat had greater numbers of 3- to 5-mm and greater than 15-mm follicles. In conclusion, feeding fat did not influence 15-keto-13,14-dihydro-prostaglandin F2 alpha or luteinizing hormone dynamics but did alter the average number of follicles within different size classes and the diameter of largest and second largest follicle after progesterone treatment.  相似文献   
9.
In 1990 the electricity in the Netherlands will be generated for more than 50% with coal as fuel. Fireside corrosion causes a minor, but from an economic point of view not negligible, contribution to unforseen plant unavailability. Measures are taken concerning materials, additives and coal blending. Around 1980 heavy oil had an essential (40%) part in the power generation: experiences with corrosion and additives from that period are summarized. Research has been carried out with new coextruded materials under severe corrosion conditions in order to improve the overall unit efficiency. Creep tests at elevated temperatures have been performed in connection to this. Furthermore research is going on concerning the effects of low NOx burning techniques (on the corrosion behaviour of waterwall tubes) and in the field of IGCC-plants.  相似文献   
10.
Farmer-led, participatory approaches are being increasingly employed in agricultural research, with promising results. This study aimed to understand how a participatory approach based on the Danish stable schools could help to achieve practical, farmer-led changes that reduced reliance on antimicrobials in the UK. Five facilitated farmer action groups comprising 30 dairy farms across South West England met on farm at regular intervals between 2016 and 2018, and worked collaboratively within their groups to discuss how to reduce antimicrobial use. Qualitative data from group discussions and individual semi-structured interviews were collected and analyzed using thematic analysis to explore how the approach helped farmers address and deal with changes to their on-farm practices. Facilitator-guided reviews of antimicrobial use and benchmarking were carried out on each farm to assess any change in usage and help farmers review their practices. The pattern of antimicrobial use changed over the 2 yr of the study, with 21 participating farms reducing their use of highest-priority critically important antibiotics (6 farms were not using any of these critical medicines from the outset). Thirty practical action plans were co-developed by the groups with an average implementation rate of 54.3% within a year. All assessed farms implemented 1 recommendation, and many were still ongoing at the end of the study. Farmers particularly valued the peer-to-peer learning during farm walks. Farmers reported how facilitated discussions and action planning as a peer group had empowered them to change practices. Participants identified knowledge gaps during the project, particularly on highest-priority critically important antibiotics, where they were not getting information from their veterinarians. The study demonstrated that facilitation has a valuable role to play in participatory approaches beyond moderating discussion; facilitators encouraged knowledge mobilization within the groups and were participants in the research as well. Facilitated, farmer-led, participatory approaches that mobilize different forms of knowledge and encourage peer learning are a promising way of helping farmers to adapt and develop responsible practices.  相似文献   
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