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Conversion of coal to carbon-free energy carriers, [H.sub.2] and electricity, with C[O.sub.2] capture and storage may have the potential to satisfy at a comparatively low cost much of the energy requirements in a carbon-constrained world. In a set of recent studies, we have assessed the thermodynamic and economic performance of numerous coal-to-[H.sub.2] plants that employ [O.sub.2]-blown, entrained-flow gasification and sour water-gas shift (WGS) reactors, examining the effects of system pressure, syngas cooling via quench versus heat exchangers, 'conventional' [H.sub.2] separation via pressure swing adsorption versus novel membrane-based approaches, and various gas turbine technologies for generating co-product electricity. This study focuses on the synergy between [H.sub.2] separation membrane reactors (HSMRs) and syngas cooling with radiant and convective heat exchangers; such 'syngas coolers' invariably boost system efficiency over that obtained with quench-cooled gasification. Conventional [H.sub.2] separation requires a relatively high steam-to-carbon ratio (S/C) to achieve a high level of [H.sub.2] production, and thus is well matched to relatively inefficient quench cooling. In contrast, HSMRs shift the WGS equilibrium by continuously extracting reaction product [H.sub.2], thereby allowing a much lower S/C ratio and consequently a higher degree of heat recovery and (potentially) system efficiency. We first present a parametric analysis illuminating the interaction between the syngas coolers, high temperature WGS reactor, and HSMR. We then compare the performance and cost of six different plant configurations, highlighting (I) the relative merits of the two syngas cooling methods in membrane-based systems, and (2) the comparative performance of conventional versus HSMR-based [H.sub.2] separation in plants with syngas coolers.

The process of low cost ammonia extraction from coal for carbon dioxide storage projects in China is discussed.

The production of wind energy via natural gas turbines and compressed air energy storage to reduce greenhouse gas emissions is analyzed.

Concerns about air pollution, climate change, and oil supply insecurity, requires changes in automotive engine/fuel technologies in directions, that offer both the potential for achieving near-zero emission of air pollutants, and a substitute of petroleum. Alternative automotive engine/fuel options, which are evolving towards these goals, are compared and discussed.

As the number of cars and the amount of driving increase, it becomes necessary to reduce air pollutant emissions per car in order to meet air quality goals. Yet it [...]

Several factors must first be considered before purchasing a charge-coupled device (CCD) camera. Buyers must first examine the camera's quantum efficiency (QE) versus wavelength plot. QE measurements are often made by the CCD manufacturer and simply passed along to the camera maker. In choosing the right camera, the performance of the CCD must first be assessed against the user's requirements. Deciding how much read and dark noise can be tolerated for a specific use can pose a lot of problems. Low-read noise MPP cameras are used for low light level spectroscopy while TE-cooled cameras are used for high light level spectroscopy.

Severe local air pollution, aggravation of the global warming condition and the inaccessibility of coal reserves in China have fueled interest into alternative sources of electricity, such as wind power. Wind power has been in use in China for over 3,000 years. Studies showed that it can provide the same amount of electricity in distant electricity demand centers by combining oversized wind farms, utilizing long-distance transmission lines and large-scale electrical storage. However, problems in funding and the legal structure of the scheme must be addressed.