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Byline: S.T. Hsieh Adoption of technologies for energy production with improved environmental performance is essential for supporting world economic growth and managing the global warming and climate change issues. International cooperation is critical to ensure the environmental and energy security of world economies on a global basis. For example, the USA has acquired a great deal of useful experience in clean coal technology, which has been demonstrated with major utilities in commercial operations. The adoption and installation of clean coal technology should be given high priority worldwide. The continuous exchange of information and technology between developed and developing economies relating to current and future use of environmentally responsive technologies is of great importance. Developed economies that possess environmentally responsive technologies and financial resources should work closely with developing economies to facilitate technology transfer and trade of technologies. Cooperation between economies can result in lowering the cost of deploying clean coal technologies directed toward the clean production of energy. This paper discusses a bilateral approach, i.e. the US/China Center for Energy and Environment, to facilitate the mitigation of emissions and promote the clean use of coal to satisfy growing energy demand in developing economies.

Most research on tetrapod locomotion has focused on movement over solid substrates. The question of how animals locomote on fluid substrates is just beginning to be explored. Basilisk lizards are known for their ability to run across the surface of water to evade predators. Previous research indicates that this method of escape depends largely on how much force the animal generates when slapping the water, relative to its body mass. I ran eight green basilisk lizards (Basiliscus plumifrons) across a 3.7 m long water track. Animals ranged in size and age from two week-old hatchlings to year-old juveniles (2-60g). Runs were filmed with two high-speed Redlake video cameras operating at 250fps and 1/2500 shutter speed. Digitized coordinates from each camera were transformed into three dimensions using direct linear transformation. I divided each stride into four phases: slap, stroke, upwards recovery, and downwards recovery. In comparison to a stride on land, the slap and stroke phases are analogous to periods when the foot is in contact with the ground, while the recovery phases are analogous to when the foot is not in contact with the ground. Preliminary results suggest that there is extreme variation in the kinematics of running, both within and between individuals. Within one run, velocity may vary by as much as 18% (87.9 to 107.2 cm/s); and the slap may occur with the toe first contacting the water (toe strike), or the whole foot contacting the water (flat-foot strike). Equally large variations could be observed in 3D angular motions of the hip, knee, and ankle joints. However, while contact time ([t.sub.c], slap and stroke phases combined) may last between 0.040s and 0.064s, duty factor ([t.sub.c]/Stride period) appears to be relatively invariant (0.458 [+ or -] 0.013, mean [+ or -] se).

Geckos with adhesive toe pads rapidly climb even smooth vertical surfaces. We challenged geckos (Hemidactylus garnoti) to climb up a smooth vertical track that contained a 3D force platform. Kinematics from 3 cameras operating at 500-1000fields/s showed that geckos climbed vertically at up to 77cm/s with a stride frequency of 15Hz. Geckos used a trotting gait in the majority of trials. During each step, whole body vertical (in the direction of motion), lateral and horizontal force all decreased to zero when the animal attached or detached its toe pads. Peak vertical force was twice body weight at mid-stance. Legged animals running on a level attain a constant average velocity by accelerating and decelerating their center of mass (COM) with each step. Geckos climbed at a constant average velocity without generating decelerating forces on their COM in the direction of motion. Changes in vertical kinetic energy comprised 80% of the total change in kinetic energy. Although mass-specific mechanical power to climb was 10 times the value expected for level running, the total mechanical energy of climbing was only 5-11% greater than the potential energy change. DARPA: N00014-98-C-0183

Kinematics of geckos (Hemidactylus garnoti) rapidly ascending a vertical surface showed periods during which only a single foot was in contact with the surface. During descent geckos can have all 4 feet out of contact at once. To reveal mechanisms underlying ascending and descending ability, we measured single-leg forces of animals running up and down a vertical track that contained a force platform. During ascent, the front legs pulled toward, while hind legs pushed away from the vertical surface, generating a net moment pitching the anterior toward the surface. Differential leg function counteracts the tendency of the anterior to rotate away from the surface. During descent hind legs primarily absorbed energy, reducing speed, whereas front legs appeared largely inactive. Kinematics of ascent showed that front and rear toes are oriented in the direction of motion. During descent the hind toes are oriented opposite to the direction of motion. During ascent, attachment and detachment of the foot occupied 15 and 35% of stance time, respectively. As speed increased, th time required to attach and detach did not decrease, suggesting that the period of vertical force production might be constrained. DARPA:N00014-98-C-0183

The amphibious Pacific leaping blenny, Alticus arnoldorum, exhibits a diverse terrestrial locomotor repertoire including jumping, crawling, and climbing. All of these movements involve a stereotyped movement of placing the tail beside the head, twisting the tail axially, and then pushing off with the lateral side of the tail to straighten the body. Despite possessing no obvious modifications to its body plan, it moves about effectively and rapidly on land, whereas its fully-aquatic relatives do not. Six genera from a monophyletic clade of blennies were selected for comparison. For ease of analysis, genera were grouped according to the amount of time spent on land into terrestrial (Alticus and Andamia), amphibious (Praealticus), and aquatic (Istiblennius, Entomacrodus, and Blenniella). I expected that axial tail twisting would enhance terrestrial locomotor capability in regards to jump stability; and that terrestrial and amphibious blennies would adhere more readily to smooth surfaces than do aquatic blennies. Blennies were startled to jump and their movements were filmed with a high-speed video camera at 500 fps and 1/2000s shutter. Adhesion was quantified by tilting individual blennies in a clear, Plexiglas box. Results show terrestrial blennies adhered more readily to a smooth surface than did the aquatic blennies. Also, axial tail twisting is limited to terrestrial and amphibious blennies which exhibited greater stability during jumps. Aquatic blennies pushed off the surface with the ventral surface of their tails and tended to spin axially during jumps. Ongoing analyses of body dynamics and ground reaction forces will address how jumping blennies generate force and maintain body stability.

Amphibious behavior is found in at least 12 families of fishes. Whereas most blennies (family Blenniidae) are fully-aquatic, at least seven of the 53 genera have amphibious species. I have been examining the amphibious locomotor repertoire of the Pacific leaping blenny, Alticus arnoldorum. Found primarily in the tropical Pacific Ocean along the violent surf zones on coastlines, these blennies can leap up to five body lengths between rocks, climb up smooth surfaces such as glass, and appear to skip across the water surface. They routinely use a movement permitting extremely rapid locomotion on land, which involves twisting the tail along its longitudinal axis, curling the tail towards the head and then straightening the body. The ability to actively twist the tail along the longitudinal axis for terrestrial propulsion appears to be unique to this genus. A sister species to A. arnoldorum, Praealticus labrovittatus, the crenulate-lipped rockskipper, also comes onto land to feed, but does not exhibit tail twisting during terrestrial locomotion. Fifteen individuals of A. amoldorum and five individuals of P. labrovittatus moved freely in a glass aquarium, and were filmed with two orthogonally-oriented high-speed video cameras (250 fps). Midline splines were obtained and the coordinates transformed into three-dimensions using a custom program written in Matlab. Preliminary results suggest that A. amoldorum utilize a combination of suction and capillary adhesion to stick to smooth surfaces while climbing. I hypothesize that tail twisting significantly increases terrestrial locomotor capability in A. arnoldorum. I will compare crawling locomotion in both species and will also present preliminary results comparing tail morphology between these two species which may permit active tail twisting in propulsive locomotion.

The evolutionary transition from water to land required dramatic alterations to organismal morphology, physiology, and ecology. Among extant fishes, the ability to come out of water has evolved multiple times. One of the most spectacular examples of amphibious lifestyles in fishes is exhibited by the Pacific leaping blenny, Alticus amoldorum. Described as being almost hydrophobic, these fish are found in large numbers on rocks along the coastlines of Guam, and exhibit an extraordinary repertoire of behaviors that permit extremely rapid locomotion on land. They can leap up to five body lengths between rocks, appear to `skip' on the water surface, and can climb smooth, vertical surfaces. They are often found clinging to the undersides of algae-covered rocks. I hypothesize that these novel, acrobatic behaviors are derived from movements commonly employed by fully aquatic fishes. I filmed A. amoldorum with two high-speed video cameras (250 fps, 1/1250 s shutter) as the fish moved freely in a glass tank. The cameras were oriented such that one filmed the dorsal, and the other the lateral view. Motions of these fish were then digitized and transformed into three-dimensions using direct linear transformation. Preliminary results indicate that during `aerial' locomotion, these blennies utilize the same C- and S-start behavior as fully aquatic fishes. They use S-starts primarily to exit water; for example when leaping out of water to stick on a vertical rock face, or to continue a `skip.' They use C-starts as an escape response on land and for jumping from a solid surface. Their regular locomotion across rocks resembles a modified C-start.

Well-aligned and highly porous carbon nanofiber (CNF) arrays were obtained by a template synthesis method, using epoxy-based solution as carbon precursor in the present study. The diameter and length of the nanofiber were accord with pore size of 100 nm and thickness of 50 μm of the anodic aluminum oxide membrane, respectively. Scanning electron microscope and transmission electron microscopy showed that the open-tipped CNFs had well-defined one-dimensional (1D) structures and high porosity. N[sub 2] adsorption experiment indicated that the mesoporous CNF array exhibited a high Brunauer–Emmett–Teller surface area of 780 m[sup 2]/g. Compared with commercial active carbon, the CNF array has a higher monolayer adsorption capacity of n-hexane due to its unique pore structure. Adsorption kinetics showed that the CNFs can rapidly achieve an equilibrium coverage, indicating smaller diffusion resistance during adsorption. These results are beneficial for the hollow CNF array as a real-time gas sensing material in the future. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]