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81.
To improve the overall sustainability of MgO‐based refractory production, a novel process to produce high purity MgO from calcined low‐grade magnesite in ammonium chloride solution was developed. The process was designed on the basis of the phase equilibria of the NH4Cl‐MgCl2‐NH3‐H2O system obtained using the Mixed Solvent Electrolyte model embedded in OLI software. The optimum calcination temperature of low‐grade magnesite was determined to be 650°C in terms of the conversion ratio of magnesium and calcium in the leaching experiments. An apparent activation energy of Mg extraction was 30.98 kJ/mol, which is slightly lower than that of Ca leaching. An empirical kinetic model of magnesium extraction was also developed to describe the effects of NH4Cl concentration, particle size of calcined magnesite, and solid‐to‐liquid ratio on the extent of extraction of magnesium. At leaching time of 10 min, the leachate with high Mg/Ca molar ratio was obtained. Then, MgO with a purity of 99.09% was produced through the decomposition of intermediate 4MgCO3·Mg(OH)2·4H2O. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1933–1946, 2015  相似文献   
82.
The study of the magneto-electric effect on molten salts have been reported in a previous article in which were given the necessary conditions to measure a reproducible magneto-electric voltage and the results for an organic salt 1-ethylpyridinium bromide, in the molten state and in alcoholic and aqueous solutions, were compared. Here the study is extended to some inorganic II salts: silver chloride, potassium nitrate and sodium nitrate. A magneto-electric voltage is measured as a function of the magneto-electrics stress and also of the temperature of the molten salts. All the resulting graphs exhibited identical shapes and three characteristic parameters were noted which seemed to intercorrelate well. These results agree with those previously obtained from 1-ethylpyridinium bromide.  相似文献   
83.
Distributed scene graphs are important in virtual reality, both in collaborative virtual environments and in cluster rendering. Modern scalable visualization systems have high local throughput, but collaborative virtual environments (VEs) over a wide‐area network (WAN) share data at much lower rates. This complicates the use of one scene graph across the whole application. Myriad is an extension of the Syzygy VR toolkit in which individual scene graphs form a peer‐to‐peer network. Myriad connections filter scene graph updates and create flexible relationships between nodes of the scene graph. Myriad's sharing is fine‐grained: the properties of individual scene graph nodes to share are dynamically specified (in C++ or Python). Myriad permits transient inconsistency, relaxing resource requirements in collaborative VEs. A test application, WorldWideCrowd, demonstrates collaborative prototyping of a 300‐avatar crowd animation viewed on two PC‐cluster displays and edited on low‐powered laptops, desktops, and over a WAN. We have further used our framework to facilitate collaborative educational experiences and as a vehicle for undergraduates to experiment with shared virtual worlds. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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When combined with NMR spectroscopy, high hydrostatic pressure is an alternative perturbation method used to destabilize globular proteins that has proven to be particularly well suited for exploring the unfolding energy landscape of small single-domain proteins. To date, investigations of the unfolding landscape of all-β or mixed-α/β protein scaffolds are well documented, whereas such data are lacking for all-α protein domains. Here we report the NMR study of the unfolding pathways of GIPC1-GH2, a small α-helical bundle domain made of four antiparallel α-helices. High-pressure perturbation was combined with NMR spectroscopy to unravel the unfolding landscape at three different temperatures. The results were compared to those obtained from classical chemical denaturation. Whatever the perturbation used, the loss of secondary and tertiary contacts within the protein scaffold is almost simultaneous. The unfolding transition appeared very cooperative when using high pressure at high temperature, as was the case for chemical denaturation, whereas it was found more progressive at low temperature, suggesting the existence of a complex folding pathway.  相似文献   
87.
Do affective responses to odors vary as a function of culture? To address this question, we developed two self-report scales in the United Kingdom (Liverpool: LEOS) and in Singapore (city of Singapore: SEOS), following the same procedure as used in the past to develop the Geneva Emotion and Odor Scale (GEOS: Chrea, Grandjean, Delplanque et al., 2009). The final scales were obtained by a three-step reduction of an initial pool of 480 affective terms, retaining only the most relevant terms to describe odor-related subjective affective states and comprised of six (GEOS) or seven affective dimensions (LEOS and SEOS). These included dimensions that were common to the three cultures (Disgust, Happiness Well-being, Sensuality Desire, and Energy), common to the two European samples (Soothing Peacefulness), and dimensions that were culture specific (Sensory Pleasure in Geneva; Nostalgia and Hunger Thirst in Liverpool; Intellectual Stimulation, Spirituality, and Negative Feelings in Singapore). A comparative approach showed that the dimensional organization of odor-related affective terms in a given culture better explained data variability for that culture than data variability for the other cultures, thus highlighting the importance of culture-specific tools in the investigation of odor-related affect. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
88.
Using prospective longitudinal data on an older sample beginning prior to the death of a spouse, G. A. Bonanno et al. (2002) distinguished 5 unique trajectories of bereavement outcome: common grief, chronic grief, chronic depression, depression followed by improvement, and resilience. These trajectories having been identified, the aims of the current study were to examine differences in how respondents in each group reacted to and processed the loss. Specific hypotheses were tested regarding differences in coping, meaning making, context, and representations of the lost relationship. Results suggest that chronic grief stems from the upheaval surrounding the loss of a healthy spouse, whereas chronic depression results from more enduring emotional difficulties that are exacerbated by the loss. Both the resilient and the depressed-improved groups showed remarkably healthy profiles and relatively little evidence of either struggling with or denying/avoiding the loss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Field studies have not yet conclusively established how attributions affect adjustment to unanticipated traumatic events. This may be due, in part, to the adoption of several untested assumptions in most prior research. It has usually been assumed that attributional issues are important to people who experience a traumatic event, that such concern is adaptive, and that specific attributions (e.g., self-blame) influence subsequent adjustment. These assumptions were tested with longitudinal data collected over 18 mo from 124 parents whose children died of Sudden Infant Death Syndrome. By 3 wks postloss, 45% of parents were not concerned with attributional issues. These parents were less distressed and less likely to blame themselves or others for the death. Longitudinal analyses did not support the assumption that attributions influence subsequent adjustment. Rather, attributions to oneself or others appear to be symptomatic of distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
Because of the increasing complexity of work in people's lives and the rapid ways in which work is changing, it is likely that all applied psychologists will need greater content knowledge about work to assist clients with issues related to work choice, entry, and adjustment. This article identifies 5 knowledge domains about work that include important information for applied psychologists. These domains are as follows: (a) economics and politics, (b) work structures, (c) globalization, (d) social factors, and (e) technology. These 5 domains are outlined, as are anticipated future trends in work. The implications of these issues for applied psychologists are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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