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61.
Evaluated the relation between self-reported frequency of nightmares, a number of saliency measures of the nightmare experience, and a self-report measure of annihilation anxiety (appended) for 1,357 undergraduates from 2 independent populations. A significant positive relation was found between nightmare frequency and salience and annihilation anxiety. Findings were cross-validated across both samples. Results are discussed within the context of object relations and ego psychology theory utilizing an ego boundary model and are consistent with previous research (e.g., E. Hartmann, 1991) demonstrating boundary impairment in Ss with self-reported frequent nightmares. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Electron paramagnetic resonance (EPR) spectroscopy was used to test the presence of Ti3+ in several novel compounds also containing Ti4+ . The results obtained confirmed the presence of Ti3+ , and indicated that differences in the EPR spectral lines of Ti3+ can make differentiation easier between compounds which have X-ray diffraction (XRD) patterns that are not markedly different. 相似文献
63.
Gas from a reservoir at constant pressure and temperature is forced through a two-dimensional porous region. The surface through which the gas exits is at a specified uniform temperature and pressure. The local gas and solid matrix temperatures are assumed equal. General solutions for the local temperature and pressure in the porous medium are found as a function of a potential. This potential can be determined by solving Laplace's equation in the porous region for a simple set of boundary conditions, and the temperature and pressure will then be known functions of position. Because of the nature of the boundary conditions it is particularly convenient to solve Laplace's equation by conformai mapping. By using this technique some illustrative heat and mass flow results were calculated for a porous wall with a step in thickness, a wall supplied with gas through periodic slots, and an eccentric annular region. 相似文献
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Removal of heavy metals from aqueous systems with thiol functionalized superparamagnetic nanoparticles 总被引:3,自引:0,他引:3
Yantasee W Warner CL Sangvanich T Addleman RS Carter TG Wiacek RJ Fryxell GE Timchalk C Warner MG 《Environmental science & technology》2007,41(14):5114-5119
We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid (DMSA) are an effective sorbent material for toxic soft metals such as Hg, Ag, Pb, Cd, and Tl, which effectively bind to the DMSA ligands and for As, which binds to the iron oxide lattices. The nanoparticles are highly dispersible and stable in solutions, have a large surface area (114 m2/g), and have a high functional group content (1.8 mmol thiols/g). They are attracted to a magnetic field and can be separated from solution within a minute with a 1.2 T magnet. The chemical affinity, capacity, kinetics, and stability of the magnetic nanoparticles were compared to those of conventional resin based sorbents (GT-73), activated carbon, and nanoporous silica (SAMMS) of similar surface chemistries in river water, groundwater, seawater, and human blood and plasma. DMSA-Fe3O4 had a capacity of 227 mg of Hg/g, a 30-fold larger value than GT-73. The nanoparticles removed 99 wt% of 1 mg/L Pb within a minute, while it took over 10 and 120 min for Chelex-100 and GT-73 to remove 96% of Pb. 相似文献
66.
Eighteen sessions of cognitive–behavioral (CB) and 13 sessions of psychodynamic–interpersonal therapy obtained from experienced clinicians in a naturalistic setting were investigated to determine the various therapeutic interventions associated with high and low emotional experiencing (EXP). Clients receiving reflections and acknowledgments, affiliative and noncontrolling interventions, or interventions highlighting nonspecific client content were associated with maintained high EXP. Lengthier interventions and interventions rated as affiliative but moderately controlling were associated with shifts to low EXP. For clients of CB therapists, questions, interventions rated affiliative but controlling, and highlighting minimal emotional content were also associated with shifts to low EXP. Male therapists were associated with clients who maintained high EXP and female therapists were associated with clients who shifted to low EXP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
JR Canvin AP Marvin M Sivakumaran JC Paton GJ Boulnois PW Andrew TJ Mitchell 《Canadian Metallurgical Quarterly》1995,172(1):119-123
Mice were infected intranasally with a serotype 2 pneumococcus, a pneumolysin-negative derivative (PLN-A), or an autolysin-negative derivative (AL-2). Numbers of wild type pneumococci were seen in the lung from approximately 12 h after infection and were first detected in the blood around this time. Immunofluorescent staining of lung sections showed that pneumolysin was produced in vivo. Pneumococcal infection resulted in alteration of the composition of the blood but not the bone marrow. Some of the hematologic changes did not occur after PLN-A. PLN-A had a slower growth rate in the lung and bacteremia was delayed. AL-2 was rapidly cleared from the lungs and was not detected in the blood. These events paralleled the pattern of histology in the lung, with the severity of inflammation reduced with PLN-A and no inflammation or hematologic changes with AL-2. 相似文献
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To date, little social science understanding has been developed about what it would mean to strategically build resilience in the context of such rich interdependencies between social, technical and natural worlds. We argue that shifts in strategies to deal with urban crises marks a turn from the politics of urgency, characteristic of crisis management, towards a governance of preparedness, characterised by strategies to build urban resilience. Social science needs to develop research agendas that critically engage with different understandings of resilience and the challenges of building resilience across different scales of urban governance. 相似文献