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51.
Mesoporous (H(I)-ePt) platinum microelectrodes electrodeposited from the hexagonal (H(I)) lyotropic liquid crystalline phase are shown to be excellent amperometric sensors for the detection of hydrogen peroxide over a wide range of concentrations. Good reproducibility, high precision, and accuracy of measurements are demonstrated. Mesoporous microelectrodes retain the high rates of mass transport typical of conventional microelectrodes, and their high real surface area greatly enhances their catalytic activity. This unique combination of properties overcomes the limitations of previous amperometric hydrogen peroxide sensors and yields outstanding qualitative and quantitative results.  相似文献   
52.
Crisis management logic suggests that planning and preparing for crisis should be a vital part of institutional and policy toolkits. This paper explores the difficulties in translating this ideal into practice. It focuses on four key difficulties. First, crises and disasters are low probability events but they place large demands on resources and have to compete against front‐line service provision. Second, contingency planning requires ordering and coherence of possible threats, yet crisis is not amenable to being packaged in such a predictable way. Third, planning for crisis requires integration and synergy across institutional networks, yet the modern world is characterised by fragmentation across public, private and voluntary sectors. Fourth, robust planning requires active preparation through training and exercises, but such costly activities often produced a level of symbolic readiness which does not reflect operational realities. Finally the paper reflects on whether crisis preparedness is a ‘mission impossible’, even in the post‐9/11 period when contingency planning seems to be an issue of high political salience.  相似文献   
53.
Using the recorded response at two vertical array sites, the SimSoil model presented in the companion paper is evaluated. The SimSoil model, which describes the small strain nonlinear behavior of granular materials, is implemented as a material model in AMPLE2000, a nonlinear, one-dimensional site response analysis code. Shear wave velocity profiles and laboratory test data available for both the La Cienega site, which was instrumented over 250?m, and the Lotung site, which was instrumented over 47?m, were used to determine SimSoil model parameters. Predictions from AMPLE2000 are compared with the measured response at several elevations for earthquakes that resulted in both nonlinear and nearly linear soil behavior. Using the available laboratory data and known input motions, the predictions of the response at these sites matched the recorded response well for varied magnitudes of shaking with a single set of parameters for each site.  相似文献   
54.
The crystal structure of Sr 2 Y 0.8 Ca 0.2 Co 2 O 6 is orthorhombic below 270 K (Immm, a = 3.84029(7) Å, b = 3.80691(6) Å and c = 19.4980(3) Å at 20 K), transformed from tetragonal (I4/mmm, a = 3.82765(6) Å and c = 19.5795(3) Å) at 295 K. The crystal structure distortion is accompanied by an anomalous temperature dependence of the degree of buckling of the CoO 2 plane and is correlated with the development of anisotropic antiferromagnetic ordering of magnetic moments (2.93(2) B per Co at 20 K). A magnetically glassy state below about 35 K and variable range hopping conduction below about 64 K for were found by magnetic susceptibility and electrical resistivity measurements.  相似文献   
55.
The EPSRC funded Rethinking Project Management Network produced several insights into new directions for project management theory and practise, highlighting gaps between current theory and practise in several areas. This paper reviews the discussions around project management practitioner development that arose out of this rethinking process where project management is seen as growing from a predominantly technical skill-set to a broader practise of reflectively managing the things needed to provide a successful project outcome. In particular, the paper identifies and addresses the challenges of developing competent project managers in a world exhibiting increasingly complex project challenges, and when skilled resources at all levels are often increasingly scarce. We provide examples of practical and academic initiatives that are designed to address these challenges: internal assessment and development programs, reflective practice thesis, and distance-based critical management MBA. We conclude by speculating on some of the further challenges in developing reflective practitioners that have yet to be resolved.  相似文献   
56.
Investigated the role of limited capacity processes in the detection of automatic targets in a dual-task paradigm using both behavioral and event-related potential (ERP) measures. Six right-handed undergraduates served as Ss. An automatic detection task was paired with another concurrent discrimination while the relative importance of each task was systematically varied. The resulting performance operating characteristic showed that both the speed and accuracy of automatic detection responses were affected by the allocation of attention. Reductions in the accuracy of each task were accompanied by reductions in the amplitude of a late-positive component of the ERP (P300). The latency of the P300 component elicited by automatic targets was increased in dual-task conditions. A comparison of behavioral and ERP measures suggested the involvement of 2 separate limited-capacity processes in automatic detection: one concerned with the formation of an episodic representation of target occurrence and the other with the execution of rapid motor responses. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
Many psychological experiments generate data that form multidimensional tables of frequencies. Although these tables are conventionally analyzed by such theoretical models as signal-detection theory, a direct and atheoretical analysis of the associations present in the data gives additional valuable information about the underlying detection processes. The present article demonstrates an application of these models to psychophysiological data, which provides an attractive compliment to the more usual signal-detection theory analysis. It is suggested that direct frequency analysis can investigate quite complicated patterns of association; furthermore, it allows approximate statistical test of specific hypotheses to be run. Thus, it provides a valuable adjunct to theoretical models. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Hypothesized that, when the degree of crowding is manipulated by varying group size in cages of equal size, it is probable that crowded animals will engage in more contact than uncrowded animals. Home-cage observation of 24 male and 24 female deer mice indicates that crowded Ss do, in fact, engage in more contact behavior. Both home-cage observation and testing in pairs for pain-elicited aggression reveal that (a) crowded Ss display more agonistic behavior than uncrowded Ss, and (b) agonistic behavior increases with prolonged crowding. Support is obtained for the theory that the effect of crowding derives from contact with conspecifics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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