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An equilibrium study was made of the distribution of chromium and oxygen between liquid iron, containing less than 1 pct Cr, and simple slags of the CaO(MgO)-SiO2-FeO-Cr2O3 type in the temperature range 1526° to 1734°C The effects of slag oxidation, temperature, and basicity were observed.  相似文献   
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Understanding urban residential end uses of water   总被引:1,自引:0,他引:1  
The 'end use' of water is a breakdown of the total household water usage such as water used for toilets, showers, washing machines, taps, lawn watering, etc. Understanding end uses of water will enable water planners, water authorities and household owners determine where water is used/wasted, how much and how often. This paper describes the end uses of water from a number of single-family homes in Greater Melbourne, Australia. The study involves the analysis of water consumption data recorded at 5-s intervals from logged households collected by Yarra Valley Water in Melbourne in 2004. The study determines how much water is used for outdoor and indoor purposes in a single-family home in Melbourne and compares the water usage during winter and summer. Hourly patterns of major end uses of water are also developed. The aim of this study is to improve the understanding of the end uses of water and to assist where to focus water conservation efforts that would be most effective financially and environmentally, and be acceptable to everyone.  相似文献   
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In this article, we discuss experiences and lessons learned from deploying four mobile sensing applications on off-the-shelf mobile phones within a recreational framework called MobSens that contains elements of health, social, and environmental sensing at both individual and community levels. We describe the main components of our applications, which facilitate logging and external communications. We also outline the challenges faced when building and testing these applications and describe our strategies for overcoming them.  相似文献   
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The present review has attempted to summarize the classic symptoms and signs of aortic valve stenosis, especially in an adult. It is emphasized that all the classic signs rarely are present and their absence may mislead an unwary clinician. The diagnostic help provided by noninvasive tests, including echocardiography and phonocardiography, has been emphasized. A need for cardiac catheterization and angiography in most patients prior to corrective surgery is stressed. The natural history of the disease without operative intervention is dim and a significant risk of sudden death exists. The current surgical approach with immediate and long-term results is summarized. Finally, attention has been drawn to the special clinical circumstances when the aortic valve stenosis provides a strinkingly different clinical picture. We cannot find a better way to end this review than by quoting a warning note given by Thomas Lewis in 1920: "It is the faint cry of an anguished and fast failing muscle, which, when it comes, all should strain to hear, for it is not long repeated. A few months, a few years at most, and the end comes."  相似文献   
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J.M. Powers  J.C. Roberts  R.G. Craig 《Wear》1976,39(1):117-122
The influence of double-pass sliding on the surface failure of filled and unfilled dental restorative resins was evaluated. Damage was more severe for double-pass than for single-pass sliding. Wear of restorative resins and composites was influenced by the resistance to penetration and by the mode of deformation during sliding.  相似文献   
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A system for the quantitative analysis of stereo-pairs of photomicrographs has been devised using a Commodore ‘PET’ microcomputer coupled to a digitizing pad, plotter and printer. The system need not use any form of stereo-viewer and does not require any particular alignment of the photographs. Height differences, derived from parallax measurements, can be obtained quickly even by operators who might normally experience difficulties with stereoscope-based systems due to either poor stereo vision or inexperience. Three-dimensional coordinates, input from point-pairs, are stored inside the computer and may be sorted to draw line profiles along any operator-selected line. Such profiles may be referred to either the projection of the median plane of the two images or rotated (‘levelled’) to the 0° tilt plane. The operation of the system is described and illustrated using both specially-constructed left- and right-hand ‘images’ from test contours and also real SEM stereo pairs. Finally, both the potential and limitations of such a system for development and application are discussed.  相似文献   
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Life stress was studied in relation to postrecovery attrition, symptom course, and recurrence of depression over 3 yrs. Participants were 67 individuals with recurrent depression who had responded to treatment. Life stress was assessed for the prior 12 wks at acute treatment entry (T1), initial recovery (T2), and after 17 wks of sustained recovery (T3). Severe life events at T1 predicted greater attrition, a more favorable postrecovery symptom course, and a lower likelihood of recurrence over 3 yrs. Life stress at T2 was not predictive of outcomes. Finally, undesirable life events at T3 tended to predict a worse symptom course and a higher likelihood of recurrence, particularly for individuals on medication. The findings are discussed in terms of (a) different processes influenced by life stress over time and (b) limitations of existing longitudinal research for studying the effects of life stress over prolonged intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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