428 research outputs found

    The Effects of Sulfuric Acid on the Mechanical Properties of Ice Single Crystals

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    Ice single crystals of various orientations containing various concentrations of H2SO4 up to 11.5 ppm were cut from large pucks of laboratory-grown ice. Constant-strain-rate compression tests were performed on the doped ice crystals both at −20°C at an axial strain rate of 1 × 10−5 s−1 and at −10°C at 1 × 106 s−1. The stress–strain curves showed a linearly rising stress with increasing strain, followed by a sharply declining stress after reaching a peak. With further strain, the sharp decline in stress slowed. The tests clearly showed, for the first time, that this naturally occurring impurity dramatically decreases both the peak stress and the subsequent flow stress of ice single crystals. The decrease in the peak strength was related to the square root of the concentration of H2SO4 up to 11.5 ppm, suggesting that the solubility limit of H2SO4 in ice is at least 11.5 ppm. The sulfuric acid also appeared to increase the ductility of the ice. Preliminary examination of a doped ice single crystal by synchrotron X-ray topography suggested that sulfuric acid dramatically increases the grown-in dislocation density

    The Role of Compensatory Beliefs in Rationalizing Environmentally Detrimental Behaviors

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    Compensatory green beliefs (CGBs) reflect the idea that a pro-environmental behavior (e.g., recycling) can off-set the negative effects of an environmentally detrimental behavior (e.g., driving). It is thought that CGBs might help explain why people act in ways that appear to contradict their pro-environmental intentions, and inconsistently engage in pro-environmental behaviors. The present study sought to investigate the nature and use of CGBs. A series of interviews suggested that participants endorsed CGBs to: (a) reduce feelings of guilt with respect to (the assumed or actual) negative environmental impact of their actions, and (b) to defend their green credentials in social situations. Participants also justified detrimental behaviors on the basis of higher loyalties (e.g., family’s needs), or the perceived difficulty of performing more pro-environmental actions. In addition to shedding light on how, when, and why people might hold and use CGBs, the research also provides new insight into how CGBs should be assessed

    Continuous Monitoring of Plant Water Potential

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