Laser-assisted photothermal imprinting of nanocomposite

We report on a laser-assisted photothermal imprinting method for directly patterning carbon nanofiber-reinforced polyethylene nanocomposite. A single laser pulse from a solid state Nd:YAG laser (10 ns pulse, 532 nm and 355 nm wavelengths) is used to melt/soften a thin skin layer of the polymer nanocomposite. Meanwhile, a fused quartz mold with micro-sized surface relief structures is pressed against the surface of the composite. Successful pattern transfer is realized upon releasing the quartz mold. Although polyethylene is transparent to the laser beam, the carbon nanofibers in the high density polyethylene (HDPE) matrix absorb the laser energy and convert it into heat. Numerical heat conduction simulation shows the HDPE matrix is partially melted or softened, allowing for easier imprinting of the relief pattern of the quartz mold.Mechanical Engineerin

Weather, climate, and the economy: Explaining risk perceptions of global warming, 2001-10

Abstract Two series of national survey datasets (2001-10), supplemented with monthly temperature and precipitation data and unemployment data, are used to examine how weather and climate, economic performance, and individuals\u27 sociodemographic backgrounds and political orientations affect public perceptions of global warming. Consistent with previous studies, political orientations play a key rolein determining public perceptions of global warming. Democrats and liberals are more likely than Republicans and conservatives to see global warming as an immediate and serious problem. Sociodemographic characteristics are also shown to be significant factors, with young people, women, and racial minorities likely to show higher concern about global warming than their counterparts. Moreover, individuals with lower income and higher levels of education tend to be more concerned about global warming. Net of these factors, summer temperature trends over the past 10 years, among other weather and climate measures, are shown to have consistently positive effects on public perceptions of global warming. This suggests that individuals who have experienced increasing summer heat are most likely to perceive immediate impacts and severity of global warming. Surprisingly, macroeconomic conditions - represented by the unemployment rate at the county level - do not appear to influence public perceptions of global warming

Science, scientists, and local weather: Understanding mass perceptions of global warming

Objective: To explore the effects of long-term climate trends and short-term weather fluctuations, evaluations of scientists and science, political predispositions, religious affiliation, the information environment, and demographic attributes on individuals’ views about whether global warming exists and, if so, whether it is a result of natural cycles or human activity. Methods: We use data from the 2009 Pew General Public Science Survey, along with data on long- and short-term patterns of temperature and precipitation in individuals’ home communities. Results: We find that long-term trends in summer temperatures influence perceptions of global warming. Individuals who reside in communities with long-term warming of summer temperatures that are coupled with long-term cooling of spring temperatures are significantly more likely to perceive that global warming exists and is due to human activity. We also find that Americans\u27 attitudes toward scientists and science, political dispositions, evangelical religious affiliation, education, and some demographic attributes all have discernible effects on their perceptions of anthropogenic (man-made) global warming. Conclusion: Individuals’ attitudes toward global warming are influenced by long-term temperature trends in their home communities, as well as a variety of attitudinal and demographic attributes

Entangled SU(2) and SU(1,1) coherent states

Entangled SU(2) and SU(1,1) coherent states are developed as superpositions of multiparticle SU(2) and SU(1,1) coherent states. In certain cases, these are coherent states with respect to generalized su(2) and su(1,1) generators, and multiparticle parity states arise as a special case. As a special example of entangled SU(2) coherent states, entangled binomial states are introduced and these entangled binomial states enable the contraction from entangled SU(2) coherent states to entangled harmonic oscillator coherent states. Entangled SU(2) coherent states are discussed in the context of pairs of qubits. We also introduce the entangled negative binomial states and entangled squeezed states as examples of entangled SU(1,1) coherent states. A method for generating the entangled SU(2) and SU(1,1) coherent states is discussed and degrees of entanglement calculated. Two types of SU(1,1) coherent states are discussed in each case: Perelomov coherent states and Barut-Girardello coherent states.Comment: 31 pages, no figure