Data center design and location: Consequences for electricity use and greenhouse-gas emissions

The rapidly increasing electricity demand for data center operation has motivated efforts to better understand current data center energy use and to identify strategies that reduce the environmental impact of these buildings. This paper builds on previous data center energy modeling efforts by characterizing local climate and mechanical equipment differences among data centers and then evaluating their consequences for building energy use. Cities in the United States with significant data center activity are identified. Representative climate conditions for these cities are applied to data center energy models for several different prototypical space types. Results indicate that widespread, effective economizer use in data centers could reduce energy demand for data centers by about 20–25%, equivalent to an energy efficiency resource in the US of ∼13–17 billion kWh per year. Almost half of the potential savings would result from better airflow management and proper control sequences. The total energy savings potential of economizers, although substantial, is constrained by their limited potential for use in server closets and server rooms, which together are estimated to account for about 30% of all data center energy demand. Incorporating economizer use into the mechanical systems of larger data centers would increase the variation in energy efficiency among geographic regions, indicating that as data center buildings become more energy efficient, their locations will have an increasing effect on overall energy demand. Differences among regions become even more important when accounting for greenhouse-gas emissions. Future data center development could consider site location, along with efficiency measures, to limit the environmental impact attributable to this increasingly prominent economic sector.     

Le Groupe de travail W 45 apporte des modifications à la liste des ≪ exigences humaines ≫

Une économie planifiée au niveau central et basée sur des principes socialistes doit malgré tout faire face à l'augmentation continuelle des prix et des coûts de la construction. Un économiste de l'EGSZI, l'Institute for Building Economics and Organisation hongrois, explique dans cet article le système de collecte de données grâce auxquelles sont établis les indices des prix de la construction basés sur les coûts unitaires du travail, procédé qui ressemble par beaucoup de côtés aux systèmes de contrôle des prix appliqués dans d'autres pays.

Cet article est une version abrégée d'une étude détaillée réalisée pour la commission de travail W55 du CIB sur les problèmes économiques de la construction.     

Nutritional evaluation of kidney beans (phaseolus vulgaris): The toxic principle

Kidney bean (Phaseolus vulgaris) lectins were purified by affinity chromatography on a fetuin-Sepharose-4B column. The net protein utilisation (NPU) of rats fed on a 5% casein-containing diet was strongly depressed by these pure lectin preparations. The extent of this nutritional toxicity was found to be related to the lectin content of the diet according to the following equation: NPU = NPU_{5% casein} ?280 x (where x is the lectin content in % w/w). Thus, because in addition lectin-free kidney bean protein preparations were found to be non-toxic for rats, it is now suggested that the toxic principle of kidney bean is identical with its constituent lectins.     

Fuel miles and the blend wall: costs and emissions from ethanol distribution in the United States

From 1991 to 2009, U.S. production of ethanol increased 10-fold, largely due to government programs motivated by climate change, energy security, and economic development goals. As low-level ethanol-gasoline blends have not consistently outperformed ethanol-free gasoline in vehicle performance or tailpipe emissions, national-level economic and environmental goals could be accomplished more efficiently by concentrating consumption of gasoline containing 10% ethanol (i.e., E10) near producers to minimize freight activity. As the domestic transportation of ethanol increased 10-fold in metric ton-kilometers (t-km) from 2000 to 2009, the portion of t-km potentially justified by the E10 blend wall increased from less than 40% to 80%. However, we estimate 10 billion t-km took place annually from 2004 to 2009 for reasons other than the blend wall. This "unnecessary" transportation resulted in more than $240 million in freight costs, 90 million L of diesel consumption, 300,000 metric tons of CO(2)-e emissions, and 440 g of human intake of PM(2.5). By 2009, the marginal savings from enabling Iowa to surpass E10 would have exceeded 2.5 g CO(2)-e/MJ and $0.12/gallon of ethanol, as the next-closest customer was 1600 km away. The use of a national network model enables estimation of marginal transportation impacts from subnational policies, and benefits from policies encouraging concentrated consumption of renewable fuels.     

Nutritional evaluation of kidney beans (phaseolus vulgaris): The isolation and partial Characterisation of Toxic Constituents

Comprehensive fractionation studies on the contents of the seeds of two varieties of kidney bean (Phaseolus vulgaris) were carried out. The extent of toxicity of the fractions obtained was assessed from the depression of the growth of rats fed on a mixed diet containing 5% casein protein and 5% unfractionated bean proteins or proportional amounts of fractionated materials. The low molecular weight diffusible materials and the structural water-insoluble carbohydrate-protein complexes (10 and 73% of the seeds, respectively) were found to have had little deleterious effects on rat growth performance. However, both protein fractions, the albumins (6.3% of the seeds) and the globulins (11% of the seeds), were found to be toxic. Further fractionation with continuous high-voltage electrophoresis indicated that most of the toxicity of the albumin fraction might be related to the presence of a range of isolectins. A similar, but not identical, isolectin might also be implicated in the toxicity of the globulin fraction. In addition, these results also demonstrated that the three major storage proteins, glycoprotein I and II and the trypsin inhibitors, which altogether made up about three quarters of the total protein content, could have made a small contribution only to the toxicity of kidney beans.     

The Effect of Ionic Contaminants on Silicon Transistor Stability

The development of the beam-lead sealed-junction (BLSJ) technology (beam-lead contact metals-silicon nitride passivation) included many experiments to study the effects of various ionic contaminants on silicon transistor stability. Stress aging was performed on standard n-p-n silicon transistors (aluminum contacts and silicon dioxide protection) under various conditions of temperature, bias, contamination, and ambient. These experiments showed the following results. 1) Alkali ions and copper in a reducing ambient are detrimental to the devices. 2) A hydrogen ambient accelerates the effect of alkali ions on the transistor degradation. 3) The degradation is approximately a linear function of the reverse bias and the contamination level from 4 to 400 ? of sodium chloride. 4) Anions have only a secondary effect on the migration of alkali ions in the oxide. The BLSJ technology was developed to protect unencapsulated silicon devices from the degradation seen on standard transistors during the preceding experiments. Results have shown that the median time to failure of sodium-contaminated BLSJ transistors aged in air at 300°C is higher than that for standard silicon transistors aged under identical conditions.     

Environmental Assessment of Logistics Outsourcing

Environmental awareness is increasingly important to society, government, and industry, and there is a strong demand for sustainable development practices. The importance of supply chain management is critical, as it characterizes and influences the life cycles of all products. Within the major logistics trends, outsourcing has a significant potential to increase sustainability in the supply chain as third-party logistics providers (3PLs) focus on improving resource utilization and making processes more efficient. However, their motivation is largely economic, and an environmental perspective is rarely seen in 3PLs. As consumers demand greener alternatives and, subsequently, environmental regulatory measures are implemented, 3PLs will have to become more environmentally and socially aware in order to develop sustainability goals. This study compares two scenarios using life-cycle assessment (LCA): one where logistics functions are handled in-house, and an alternative scenario where such functions are outsourced to a 3PL. The impacts of logistics outsourcing on energy utilization, global warming potential, and fatalities are first quantified in the supply chain of an automobile. Even though vehicle operation, responsible for most of the impacts considered, is outside the domain of logistics functions, logistics outsourcing nonetheless has the potential to reduce energy use and global warming potential by 0.4–2% and fatalities by 0.8–3.3% throughout the entire life cycle of a typical automobile. Road and air transportation are found to account for most of the impacts in all selected metrics. Analyzing logistics outsourcing in the other sectors of the U.S. economy revealed the same trend as observed in the supply chain of an automobile.     

Organs relative weight and plasma amino acid concentrations in rats fed diets based on whole legume (faba bean,lupin, chickpea,defatted soybean) seed meals or their fractions

The effects on organ relative weights (g per 100 g bw) and plasma amino acid concentrations of diets based in legume (faba bean (Vicia faba), lupin (Lupinus angustifolius), chickpea (Cicer arietinum) and soybean (Glycine max)) seed meals as the only source of protein were studied with growing rats using lactalbumin or casein as controls. Also, legume seed meal extracted globulins were included in control diets replacing lactalbumin to produce legume globulin‐based diets, and legume residue fractions, containing most of the starch and/or insoluble fibre (NSP+lignin) from the seed meals, were included in control diets to reach the same amounts present in whole legume seed meal diets. All experimental diets were formulated to contain the same amounts of protein (100 g kg⁻¹) and energy (15.5 kJ g⁻¹), and were supplemented with essential amino acids. Compared with lactalbumin, higher relative weights of gastrointestinal sections were determined in rats fed legume seed meals or their corresponding residue fractions. On the contrary, spleen relative weight was lower in rats fed diets containing lupin, chickpea or soybean meals or extracted globulins, while residue fractions had no effect on it. Thymus relative weight was also lower in rats fed whole chickpea seed meal or any of the extracted legume globulins. Except for chickpea meal, animals fed legume‐ or legume protein‐based diets had lower liver relative weights than controls. Lower proportions (mg g⁻¹ tissue) of glycogen, and lower total protein and RNA, were also determined in the livers of rats fed lupin seed meal. Free plasma concentrations (mM litre ⁻¹) of glycine, histidine and arginine were higher, and threonine, leucine and lysine were lower, in rats fed diets based in all legume seed meals of their respective globulin proteins. The possible reasons and implications of these results are discussed. © 1999 Society of Chemical Industry     

Reductive defluorination of perfluorooctane sulfonate

Perfluorooctane sulfonate (PFOS) is under increased scrutiny as an environmental pollutant due to recent reports of its worldwide distribution, environmental persistence, and bioaccumulation potential. The susceptibility of technical PFOS and PFOS branched isomers to chemical reductive dehalogenation with vitamin B12 (260 microM) as catalyst and Ti(III)-citrate (36 mM) as bulk reductant in anoxic aqueous solution at 70 degrees C and pH 9 was evaluated in this study. Defluorination was confirmed by fluoride release measurements of 18% in technical PFOS, equivalent to the removal 3 mol F-/mol PFOS, and 71% in PFOS branched isomers equivalent to the removal of 12 mol F-/mol PFOS. Degradation of PFOS was further confirmed by monitoring the disappearance of PFOS compounds with reaction time by suppressed conductivity ion chromatography, LC-MS/MS, and 19F NMR studies. The PFOS compounds differed in their susceptibility to reductive degradation by vitamin B12Ti(III) citrate. Chromatographic peaks corresponding to branched PFOS isomers disappeared whereas the peak corresponding to linear PFOS was stable. To our knowledge this is the first report of reductive dehalogenation of PFOS catalyzed by a biomolecule.