Research needs for coal gasification and coal liquefaction

We describe essential features of developing coal-gasification and coal-liquefaction technologies and summarize the current development status and important R&D needs for these processes.     

Complicating neoliberalization and decentralization: the non-linear experience of Colombian water supply, 1909–2012

This article presents key elements in the evolution of water supply regulation in Colombia over the twentieth century. This is novel in that it contradicts widely accepted and seemingly universal trends in water supply development. By putting apparently recent phenomena into a longer historical trajectory, we are able to nuance the idea of a unidirectional transition from centralized to decentralized governance, as well as the evolution of policies associated with neoliberalization. We find that regulatory development began at the municipal scale in the 1920s, only to be centralized mid-century. By the same token, policies typically associated with neoliberalization – such as corporatization, full cost recovery, and volumetric metering – began in the 1910s and 1920s and not under neoliberalism in the 1980s. The work is based on a database compiled by the authors. The database comprises municipal, departmental and state regulatory interventions from 1909 to 2012.     

Phosphorylation- and activation-independent association of the tyrosine kinase Syk and the tyrosine kinase substrates Cbl and Vav with tubulin in B-cells

Aggregation of the B-cell antigen receptor leads to the activation of the 72-kDa Syk protein-tyrosine kinase and the phosphorylation of tubulin on tyrosine. To explore the requirement of Syk catalytic activity for tubulin phosphorylation, tubulin was isolated from cytosolic fractions from anti-IgM-activated B-cells (DT40) that lacked endogenous Syk and immunoblotted with anti-phosphotyrosine antibodies. Tubulin was not tyrosine-phosphorylated in Syk- B-cells. Phosphorylation could be restored by the expression of wild-type, but not catalytically inactive, Syk. However, both catalytically inactive and wild-type Syk were capable of constitutive association with tubulin, indicating that tubulin phosphorylation is not required for this interaction. Anti-phosphotyrosine antibody immunoblotting of proteins adsorbed to colchicine-agarose revealed the presence of three major tubulin-associated phosphoproteins of 110, 90, and 74 kDa, the phosphorylation of which was dependent on Syk expression. The proteins of 110 and 90 kDa were identified as Cbl and Vav, two proto-oncogene products known to become prominently phosphorylated following receptor engagement. Both proteins were shown to be constitutively associated with tubulin.     

Monte Carlo Simulations for Tomlinson Sliding Models for Non-Sinusoidal Periodic Potentials

It is shown that the velocity dependence of a tungsten tip sliding against a mica surface cannot be fit to a semi-empirical analytical solution of the Tomlinson/Prandtl model using a simple sinusoidal sliding potential. This could be due to invalid assumptions in the model itself. However, if it is assumed that the periodic sliding potential is much sharper than a simple sinusoid, quantitative agreement between the experimental velocity dependence of the sliding force and theory is obtained using a single variable parameter, the height of the surface potential. Sliding is modeled in this case using Monte Carlo theory, and it is found that the height of the potential varies linearly with the normal load.     

Pilot Plant Study of the Effect of a Surface Electric Field on Fabric Filter Operation

Electrostatic fields at the fabric surface of fabric dust collectors have been observed in the laboratory to reduce the flow resistance of the collected dust and to reduce the dust penetration into the fabric. A pilot plant study of electrostatically augmented fabric filtration was undertaken to transfer the laboratory technology to the field environment. Pilot plant results are presented. These results are interpreted with respect to dust cake structure and properties.     

Steroid hormone runoff from agricultural test plots applied with municipal biosolids

The potential presence of steroid hormones in runoff from sites where biosolids have been used as agricultural fertilizers is an environmental concern. A study was conducted to assess the potential for runoff of seventeen different hormones and two sterols, including androgens, estrogens, and progestogens from agricultural test plots. The field containing the test plots had been applied with biosolids for the first time immediately prior to this study. Target compounds were isolated by solid-phase extraction (water samples) and pressurized solvent extraction (solid samples), derivatized, and analyzed by gas chromatography-tandem mass spectrometry. Runoff samples collected prior to biosolids application had low concentrations of two hormones (estrone <0.8 to 2.23 ng L(-1) and androstenedione <0.8 to 1.54 ng L(-1)) and cholesterol (22.5 ± 3.8 μg L(-1)). In contrast, significantly higher concentrations of multiple estrogens (<0.8 to 25.0 ng L(-1)), androgens (<2 to 216 ng L(-1)), and progesterone (<8 to 98.9 ng L(-1)) were observed in runoff samples taken 1, 8, and 35 days after biosolids application. A significant positive correlation was observed between antecedent rainfall amount and hormone mass loads (runoff). Hormones in runoff were primarily present in the dissolved phase (<0.7-μm GF filter), and, to a lesser extent bound to the suspended-particle phase. Overall, these results indicate that rainfall can mobilize hormones from biosolids-amended agricultural fields, directly to surface waters or redistributed to terrestrial sites away from the point of application via runoff. Although concentrations decrease over time, 35 days is insufficient for complete degradation of hormones in soil at this site.     

Efficiency of conventional drinking-water-treatment processes in removal of pharmaceuticals and other organic compounds

Samples of water and sediment from a conventional drinking-water-treatment (DWT) plant were analyzed for 113 organic compounds (OCs) that included pharmaceuticals, detergent degradates, flame retardants and plasticizers, polycyclic aromatic hydrocarbons (PAHs), fragrances and flavorants, pesticides and an insect repellent, and plant and animal steroids. 45 of these compounds were detected in samples of source water and 34 were detected in samples of settled sludge and (or) filter-backwash sediments. The average percent removal of these compounds was calculated from their average concentration in time-composited water samples collected after clarification, disinfection (chlorination), and granular-activated-carbon (GAC) filtration. In general, GAC filtration accounted for 53% of the removal of these compounds from the aqueous phase; disinfection accounted for 32%, and clarification accounted for 15%. The effectiveness of these treatments varied widely within and among classes of compounds; some hydrophobic compounds were strongly oxidized by free chlorine, and some hydrophilic compounds were partly removed through adsorption processes. The detection of 21 of the compounds in 1 or more samples of finished water, and of 3 to 13 compounds in every finished-water sample, indicates substantial but incomplete degradation or removal of OCs through the conventional DWT process used at this plant.     

光模块部署的现状和未来发展

手捡起任何一本电信业杂志,总能发现一、二 篇有关光模块的报道。有的是关于某家电信公 司发布的新组件或新器件,有的是关于制作器件所涉及的技术难题。遗憾的是,很多文章未能解释清楚光模块的设计和应用。满足各种需求的模块当前光模块的核心都有一个基本功能,就是在电气和光传输网络之间提供接口。确实,众多线路卡供应商具有设计和交付1Gb/s以下专用链路的生产资源。而当数据速率增加至2.5Gb/s、10Gb/s、甚至40Gb/s时,显然缺乏可用的设计技术,增加了研发这类接口,使之同步增长所需的时间预算。这是促使人们不断关注…