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131.
The permittivity and the dielectric loss of ternary mixtures of equimolar concentrations of m-cresol, o-cresol with acetonitrile, acrylonitrile and benzonitrile in benzene have been measured at 8.33 GHz and 308 K. The distribution parameter α, the most probable relaxation time τ, the relaxation time for overall rotation of the molecule τ(1), the relaxation time for group rotation τ(2), and the excess dipole moment for various systems have been calculated by the Cole-Cole and Higasi methods. Data has been analyzed in terms of two-relaxation processes: overall rotation and group rotation.  相似文献   
132.
The strain-hardening behaviour of metals and alloys are significantly affected by the dynamic recovery process, the rate of which can be increased by increases in deformation temperature and/or stacking fault energy (SFE). In the present work, the decay slope of the strain-hardening rate with flow stress as a function of both temperature and stacking fault energy is quantitatively evaluated for several face-centered cubic metals and alloys. A universal and quantitative approach to the scaling of the effects of temperature and stacking fault energy on strain-hardening behaviour is developed, which could be useful for predicting deformation behaviour or for material design.  相似文献   
133.
Thin films of Ga x Te100? x (x?=?3, 6, 9 and 12) have been synthesized by thermal evaporation. From SEM images, it is observed that all the films contain nanoparticles of sizes varying from 100 to 200?nm. The dc electrical conductivity of the as-deposited films of Ga x Te100?x nanoparticles is measured as a function of temperature range from 298 to 383?K, and increases exponentially with temperature. The value of the activation energy, calculated from the slope of ln?σ dc versus 1000/T plots, is found to decrease with increase in the Ga content. On the basis of the value of the pre-exponential factor σ o, it is suggested that the conduction is due to thermally assisted tunneling of carriers in localized states near the band edges. The optical measurements suggest an indirect optical band gap in this system. The value of the optical band gap decreases on increasing the Ga concentration.  相似文献   
134.
Photo-induced phenomena in glasses excited by two-photon absorption have been studied and compared with those produced by bandgap illumination. The two-photon excitation of As2S3 gives a refractive-index increase, unaccompanied by photodarkening. Raman-scattering spectra show that the excitation increases the density of ‘wrong’ bonds. These observations are discussed and compared with photo-induced changes in SiO2.  相似文献   
135.
The evolution of consciousness is seen in the context of energy driven evolution in general in which energy and information, or the in‐forming of complex structure, are seen as two sides of the same coin. From this perspective consciousness is viewed as an ecological system in which streams of cognitive, perceptual, and emotional information form a rich complex of interactions, analogous to the interactive metabolism of a living cell. The result is an organic, self‐generating, or autopoietic, system, continuously in the act of creating itself. Evidence suggests that this process is chaotic, or at least chaotic‐like, and capable of assuming a number of distinct states best understood as chaotic attractors. Such systems do not exist in isolation, but function most normally in hypercomplex attractor patterns termed societies.  相似文献   
136.
The human species faces crises of critical proportions. Excessive population, global warming, and the anticipated descent from peak fossil-fuel extraction promise to change our future in far-reaching ways. Operant conditioning prepares the individual for a world similar to the selecting past, but our world is changing more rapidly than our adaptation. As individuals, we cannot make substantial changes in the world at large because we do not control enough reinforcers, but we can turn to the sources of our personal behavior and manipulate them. We will need help. Better organized social networks and the self-management techniques they support can promote immediate changes in consumption at home, work, and moving about in our personal worlds. Surprisingly, consuming less can lead to more satisfying and happier lives, but a better understanding of reinforcement contingencies is necessary. We can recover the strengthening effects of personal daily accomplishments that are eroded when conditioned generalized reinforcers intervene. When we get our own personal lives in order we can reduce our carbon footprints, restore the connections between our behavior and its strengthening effects, and become models worthy of imitation.  相似文献   
137.
Martire  Lynn M.  Stephens  Mary Ann Parris 《Sex roles》2003,48(3-4):167-173
We review findings from our programmatic research on adult daughters who are simultaneously involved in the roles of employee and care provider to an impaired parent. Two opposing theoretical perspectives on the health effects of occupying these two roles are described, and empirical findings that bear on each perspective are presented. Our review reveals that, consistent with the competing demands perspective, parent care and employment often conflict with one another. Consistent with the energy expansion perspective, however, there is evidence that holding these two roles can be beneficial for the health of adult daughters.  相似文献   
138.
Summary  Well known quantum and time paradoxes, and the difficulty to derive the second law of thermodynamics, are proposed to be the result of our historically grown paradigm for energy: it is just there, the capacity to do work, not directly related to change. When the asymmetric nature of energy is considered, as well as the involvement of energy turnover in any change, so that energy can be understood as fundamentally “dynamic”, and time-oriented (new paradigm), these paradoxes and problems dissolve. The most basic consequence concerns the particle-wave dualism. For a reversible inter-conversion of a particle into a wave, subject to a dynamic energy, a self-image of information has to be generated: quantum theory has to be complemented by a theory of information. Then, quantum processes can be derived from classical ones and the second law of thermodynamics with the tendency of increasing entropy follows in a straightforward way.  相似文献   
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140.
Risk-sensitive foraging models predict that choice between fixed and variable food delays should be influenced by an organism's energy budget. To investigate whether the predictions of these models could be extended to choice in humans, risk sensitivity in 4 adults was investigated under laboratory conditions designed to model positive and negative energy budgets. Subjects chose between fixed and variable trial durations with the same mean value. An energy requirement was modeled by requiring that five trials be completed within a limited time period for points delivered at the end of the period (block of trials) to be exchanged later for money. Manipulating the duration of this time period generated positive and negative earnings budgets (or, alternatively, "time budgets"). Choices were consistent with the predictions of energy-budget models: The fixed-delay option was strongly preferred under positive earnings-budget conditions and the variable-delay option was strongly preferred under negative earnings-budget conditions. Within-block (or trial-by-trial) choices were also frequently consistent with the predictions of a dynamic optimization model, indicating that choice was simultaneously sensitive to the temporal requirements, delays associated with fixed and variable choices on the upcoming trial, cumulative delays within the block of trials, and trial position within a block.  相似文献   
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