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We conduct a consequential lifecycle analysis (LCA) of greenhouse gas (GHG) emissions from North American liquefied natural gas (LNG) export projects, estimating the change in global natural gas and coal use resulting from the market effects of increased LNG trade. We estimate that building a 2.1 billion cubic feet per day (Bcfd) LNG export facility, equivalent to one of the larger LNG projects under development in the US today, will change global GHG emissions −39 to 11 Mt CO2e (90% range) with a median value of −8 Mt CO2e. Previous attributional LCA methods for electricity generation with LNG replacing coal find a much larger benefit of LNG exports, a median value of −36 Mt CO2e for this size project. The smaller decrease in GHGs is attributable to higher domestic coal use and a smaller decrease in international coal use than assumed by previous methods. Net global emission change estimates are most sensitive to the uncertainty in economic elasticities outside of North America. Given the scale of planned and proposed LNG export terminals, project regulators and policymakers must account for market effects to more accurately estimate the global net change in GHG emissions.

Considers solutions for reducing carbon emission levels in the United States (U.S.). Key source of carbon emission in the U.S.; Potential technologies to power motor vehicles with no net carbon dioxide emissions; Economic and environmental considerations on the alternatives; Difficulties facing a switch from gasoline to cellulosic ethanol.

Summary A tentative structure and composition of a surfactant, BL-86, produced byBacillus licheniformis 86 is described. The surfactant is a mixture of lipopeptides with the major components ranging in size from 979 to 1091 Da and varying in increments of 14 Da. The variation in molecular weight represents changes in the number of methylene groups in the lipid and/or peptide portion of the surfactant. There are 7 amino acids per molecule. The peptide portion is composed of the following amino acids: glutamic acid or glutamine (glx), aspartic acid or asparagine (asx), valine, leucine, and isoleucine at a ratio of 1.0:1.0:1.4:3.0:0.6, respectively. The leucine is present as both thed andl isomers at a ratio of about 2:1, respectively. Forty percent of the molecules containl-valine instead ofl-isoleucine. The glx and asx are present as a combination ofl-glutamic acid andl-asparagine and/orl-glutamine andl-aspartic acid. The N-terminus of the peptide is blocked, most likely by a peptide bond to the lipid portion. An ester carbonyl structure is present, which could be a part of a lactone ring connecting the ß position of the lipid to one of the carboxyl groups in the peptide. The lipid portion is composed of, on average, 8–9 methylene groups, and contains a mixture of linear and branched tails. Results of DCI-MS and FAB-MS analyses, as well as surface tension measurements, of purified BL-86 HPLC fractions support the proposed composition.

Summary Surfactant (BL86) was isolated from foam produced during growth ofBacillus licheniformis 86 by acid-precipitation followed by extraction into tetrahydrofuran or methanol. The surfactant is anionic and dissolves in tetrahydrofuran, methanol, chloroform, dichloromethane, xylene, toluene, and alkaline water. The surfactant lowers the surface tension of water to 27 dynes/cm, and achieves the critical micelle concentration with as little as 10 µg surfactant/ml. Its interfacial tension can reach 0.36 dynes/cm when measured in 4% sodium chloride againstn-hexadecane. The surfactant is stable from pH 4.0 to 13.0, at temperatures ranging from 25 to 120°C, and in salt solutions ranging from 0 to 30% NaCl. Preliminary analytical results indicate that the surfactant is a mixture of lipopeptides different from previously reportedBacillus produced surfactants.

The article presents a reaction to the energy resources policy employed by the U.S. government as of March 2006. The authors of the article have analyzed and found that the U.S. can have a gasoline substitute at an attractive price with little infrastructure investment and no change to our current fleet of cars and light trucks. By 2016, the country could produce and import roughly 30 billion gallons of ethanol from corn, sugar cane, and grasses and trees, lowering gasoline use dramatically. Furthermore, the U.S. could encourage the European Union, Japan, and other rich nations to raise their ethanol production at home and in developing nations by a similar amount. Such increased production, together with improvements in vehicle fuel economy, would result in a notable decrease in petroleum demand, with positive implications for oil prices and Middle Eastern policy.