We have fabricated multiwalled carbon nanotubes (CNTs) with flowing acetylene, using a well-ordered porous anodic aluminum oxide (AAO) nanotemplate with or without deposition of Co in the pores as a catalyst. Without deposition of Co, the tubes were made in the pores having the shape of the pores by catalysis with the alumina of the AAO templates. With deposition of Co, both alumina and Co could work as a catalyst. By widening the pores after Co deposition, tubes grow out from the pores, by forming a tube-in-tube, which could be used for electrochemical energy storage. Since the alumina of the AAO templates works as a catalyst, one can fabricate special shapes of CNTs by designing the pores of AAO templates. We have succeeded for the first time to fabricate linearly joined CNTs by using AAO templates prepared by using pore widening and multianodization techniques. The electronic properties of the linearly joined CNTs will be affected critically by the junctions that contain five-and seven-membered carbon ring defects and could be controlled by changing the ratio of the two diameters of them. A schematic to fabricate FET (field-effect transistor) using the linearly joined CNTs fabricated on AAO templates has been suggested.

-In this paper, a new energy harvesting technology using stray electric field of an electric power line is presented. It is found that energy can be harvested and stored in the storage capacitor that is connected to a cylindrical aluminum foil wrapped around a commercial insulated 220 V power line. The average current flowing into 47 µF storage capacitor is about 4.53 µA with 60 cm long cylindrical aluminum foil, and it is possible to operate wireless sensor node to transmit RF data every 42 seconds. The harvested average power is about 47 µW in this case. Since the energy can be harvested without removing insulating sheath, it is believed that the proposed harvesting technology can be applied to power the sensor nodes in wireless ubiquitous sensor network and smart grid system.

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A new energy harvesting technology that extracts energy from the stray electric field around a three-wire AC power line is presented. It is observed that when 20 cm of the insulated power line is surrounded with a conductive sheet, about 20 mJ of energy is harvested in 15 min with a 1 μF storage capacitor. An autonomous harvesting circuit was designed and built adopting an MEMS switch as a low leakage, low power consumption and hysteretic switch. It is demonstrated that the harvested energy is utilised to drive a commercial Zigbee-based wireless sensor module autonomously. Since it is easy and safe to install, the proposed stray electric field harvesting technology should greatly expand the field in which wireless sensors are required, such as home automation, smart grid, building energy management and structural health monitoring, as long as power lines are available nearby.

The galvanostatic lithiation/sodiation voltage profiles of hard carbon anodes are simple, with a sloping drop followed by a plateau. However, a precise understanding of the corresponding redox sites and storage mechanisms is still elusive, which hinders further development in commercial applications. Here, a comprehensive comparison of the lithium‐ and sodium‐ion storage behaviors of hard carbon is conducted, yielding the following key findings: 1) the sloping voltage section is presented by the lithium‐ion intercalation in the graphitic lattices of hard carbons, whereas it mainly arises from the chemisorption of sodium ions on their inner surfaces constituting closed pores, even if the graphitic lattices are unoccupied; 2) the redox sites for the plateau capacities are the same as those for the closed pores regardless of the alkali ions; 3) the sodiation plateau capacities are mostly determined by the volume of the available closed pore, whereas the lithiation plateau capacities are primarily affected by the intercalation propensity; and 4) the intercalation preference and the plateau capacity have an inverse correlation. These findings from extensive characterizations and theoretical investigations provide a relatively clear elucidation of the electrochemical footprint of hard carbon anodes in relation to the redox mechanisms and storage sites for lithium and sodium ions, thereby providing a more rational design strategy for constructing better hard carbon anodes.

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This paper investigates the impact of economic growth, and more specifically robust economic growth along with other macroeconomic determinants, on poverty levels using both the U.S. official measure of poverty and an estimated time series of Sen indices of poverty. The results reveal that the period of robust economic expansion that the U.S. economy experienced during the 1990s did not have a significant impact on poverty using either measure. In addition, we find that the impact of growth and other macro controls is dramatically different when a subset of the poverty population, namely non-white poverty, is investigated. The percentage of households headed by women is shown to be a significant factor in examining poverty for this subgroup. Copyright 2004 Blackwell Publishing Ltd.

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