The use of chromium waste sludge for the adsorption of colour from dye effluent streams

Adsorption studies show that chromium hydroxide precipitates can be used for the removal of methylene blue, reactive blue, congo red and disperse orange dyes from aqueous media. Three different mechanisms are involved: attraction of positive surface charges on the precipitate at low pH for dye anions (reactive blue and congo red); attraction of negative surface charges on hydroxide at high pH for dye cations (methylene blue), and dye particle entrapment for the neutral disperse orange. The point of zero charge of the chromium hydroxide precipitate based on the dye adsorption studies is pH 10.5. The changes in the surface charge of such precipitates with pH can be used to achieve the removal of any charged dye species. © 2002 Society of Chemical Industry     

Evaluation of a new instrument offering sodium,potassium, and ionized calcium in combination with haematocrit,pH and blood gas analysis; the performance of the Nova Stat Profile 1

The Nova Stat Profile 1 analyser, a combined sodium, potassium, ionized calcium, haematocrit and conventional blood gas analyser, was evaluated over a four month period. In addition to assessing and demonstrating that the instrument met analytical requirements, an appreciation of the use of ionised calcium (iCa) was made. Prospective costs were characterised and practical problems of iCa measurement addressed.     

Titanium Sheet Fabricated from Powder for Industrial Applications

In collaboration with Ametek and Commonwealth Scientific and Industrial Research Organization (CSIRO), Oak Ridge National Laboratory has evaluated three different methods for converting titanium hydride?Cdehydride (HDH) powder into a thin-gauge titanium sheet from a roll-compacted preform. Methodologies include sintering, followed by cold rolling and annealing; direct hot rolling of the roll-compacted sheet; and hot rolling of multiple layers of roll-compacted sheet that are encapsulated in a steel can. Fabrication of fully consolidated sheet has been demonstrated using all three methods, and each processing route has the ability to produce a sheet that meets ASTM B265 specifications. However, not every method currently provides a sheet that can be highly formed without tearing. The degree of sintering between powder particles, postprocessing density, and the particle-to-particle boundary layer where compositional variations may exist have a significant effect on the ability to form the sheet into useful components. Uniaxial tensile test results, compositional analysis, bend testing, and biaxial testing of the titanium sheet produced from hydride?Cdehydride powder will be discussed. Multiple methods of fabrication and the resulting properties can then be assessed to determine the most effective and economical means of making components for industrial applications.     

Effect of pre-dehulling treatments on some nutritional and physical properties of navy and pinto beans (Phaseolus vulgaris L.)

The effect of pre-dehulling treatments using low and high temperatures on some nutritional and physical properties of navy and pinto beans was investigated. Beans were exposed to water (14%, 28% and soaking 1:5, w/v for 6 h, 16 and 16 h, respectively) to facilitate seed coat detachment prior to freeze drying (FD) for 48 h or heat drying (HT) for 20 or 60 min. Exposure to the highest moisture levels produced the largest seed coat yields (17.38-20.91%) and was independent of the drying conditions. The total phenolic content was positively correlated to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) antioxidant activity and increased as the exposure time to HT increased, but it was unaffected by the FD. The nutritional properties of the bean varieties differed significantly, phytic acid was unaffected, and the highest antioxidant activity was observed on the seed coats of HT pinto beans (69.24-84.46% of DPPH discoloration). Significant physical changes were observed for the HT seeds, with the highest yellowness and the lowest peak viscosity detected in the soaked and HT (60 min) beans.     

Energy literacy of secondary students in New York State (USA): A measure of knowledge,affect, and behavior

Energy literacy, which encompasses broad content knowledge as well as affective and behavioral characteristics, will empower people to make appropriate energy-related choices and embrace changes in the way we harness and consume energy. Energy literacy was measured with a written questionnaire completed by 3708 secondary students in New York State, USA. Results indicate that students are concerned about energy problems (affective subscale mean 73% of the maximum attainable score), yet relatively low cognitive (42% correct) and behavioral (65% of the maximum) scores suggest that students may lack the knowledge and skills they need to effectively contribute toward solutions. High school (HS) students scored significantly better than middle school (MS) students on the cognitive subscale; gains were greatest on topics included in NY State educational standards, and less on topics related to “practical” energy knowledge such as ways to save energy. Despite knowledge gains, there was a significant drop in energy conservation behavior between the MS and HS students. Intercorrelations between groups of questions indicate energy-related behaviors are more strongly related to affect than to knowledge. These findings underscore the need for education that improves energy literacy by impacting student attitudes, values and behaviors, as well as broad content knowledge.     

Identifying the effect of polar constituents in coal-derived NAPLs on interfacial tension

Interfacial tension, which is a critical variable affecting multiphase flow of nonaqueous phase liquids (NAPLs) in the subsurface, varies greatly with the composition of complex NAPLs recovered from field sites. Much of this variability stems from the presence of acid and base molecules in the NAPL mixture. The interfacial tension and acid and base concentration in six coal-derived NAPLs were measured. Creosotes generally have lower interfacial tensions due to their higher concentrations of organic acid and base macromolecules as compared with coal tar samples. Interfacial tension is a function of pH, with lower values measured at pH greater than approximately 9. At a neutral pH, the interfacial tensions are inversely proportional to the total acid concentration. Asphaltenes in these coal-derived NAPLs account for most of the acid and base constituents. It is found in this study that acid and base numbers are valuable indicators of interfacial tension and, therefore, the capillary phenomena associated with multiphase flow behavior of NAPLs in the subsurface.     

Field evaluation of the solvent extraction residual biotreatment technology

The Solvent Extraction Residual Biotreatment (SERB) technology was evaluated at a former dry cleaner site in Jacksonville, FL, where an area of tetrachloroethylene (PCE) contamination was identified. The SERB technology is a treatmenttrain approach for complete site restoration, which combines an active in situ dense nonaqueous-phase liquid (DNAPL) removal technology, cosolvent extraction, with a passive enhanced in situ bioremediation technology, reductive dechlorination. During the in situ cosolvent extraction test, approximately 34 kL of 95% ethanol/5% water (v:v) was flushed through the contaminated zone, which removed approximately 60% of the estimated PCE mass. Approximately 2.72 kL of ethanol was left in the subsurface, which provided electron donorfor enhancement of biological processes in the source zone and downgradient areas. Quarterly groundwater monitoring for over 3 yr showed decreasing concentrations of PCE in the source zone from initial values of 4-350 microM to less than 150 microM during the last sampling event. Initially there was little to no daughter product formation in the source zone, but after 3 yr, measured concentrations were 242 microM for cis-dichloroethylene (cis-DCE), 13 microM for vinyl chloride, and 0.43 microM for ethene. In conjunction with the production of dissolved methane and hydrogen and the removal of sulfate, these measurements indicate that in situ biotransformations were enhanced in areas exposed to the residual ethanol. First-order rate constants calculated from concentration data for individual wells ranged from -0.63 to -2.14 yr(-1) for PCE removal and from 0.88 to 2.39 yr(-1) for cis-DCE formation. First-order rate constants based on the change in total mass estimated from contour plots of the groundwater concentration data were 0.75 yr(-1) for cis-DCE, -0.50 yr(-1) for PCE, and -0.33 yr(-1) for ethanol. Although these attenuation rate constants include additional processes, such as sorption, dispersion, and advection, they provide an indication of the overall system dynamics. Evaluation of the groundwater data from the former dry cleaner site showed that cosolvent flushing systems can be designed and utilized to aid in the enhancement of biodegradation processes at DNAPL sites.     

Analysis of brandy aroma by solid‐phase microextraction and liquid–liquid extraction

Headspace solid‐phase microextraction (SPME) and continuous liquid–liquid extraction (LLX) with Freon were used to extract and analyse aroma volatiles in brandy. In general, SPME using a non‐polar polydimethylsiloxane coating was more selective for esters and acids than was LLX. LLX using Freon 11 extracted the higher alcohols more efficiently than SPME. Relative differences in volatiles between brandies made from Vitis vinifera L cv Colombard and Vitis vinifera L cv Ugni blanc were observed, particularly for hexanol, 3‐methylbutylacetate, 3‐methylbutanol and 3‐methylbutyloctanoate. In addition, a combination of SPME with GC–olfactometry was used to provide more detailed information on sensory characteristics of varietal brandies. © 2000 Society of Chemical Industry     

Associations Between Message Features and Subjective Evaluations of the Sensation Value of Antidrug Public Service Announcements

The effective targeting of high sensation-seeking adolescents, who are most at risk for drug abuse, requires the creation of high sensation value messages. Whereas previous research has focused on subjective reactions of receivers as the primary way to define message sensation value (MSV), we conceptualize message sensation value as the formal and content features (audio, visual, and format) of a message that contribute to subjective message sensation evaluations. The three objectives of this study were (a) to identify message design features that would aid in the development of effective prevention messages targeting high sensation seekers, (b) to develop an objective measure of message sensation value based on formal and content features of messages, and (c) to determine whether high message sensation value messages were associated with higher subjective evaluations of message sensation value. In the present study, 418 undergraduates each viewed 10 PSAs selected at random from a pool of 109 PSAs that had been previously coded for message sensation value. Analyses provide support for the central hypothesis of the study, indicating that perceived message sensation value is at least in part a product of the formal and content features of a PSA.     

Performance analysis and comparison of optical signal processing beamforming networks: a survey

Photonic Network Communications - Forthcoming wireless systems are developed to support greater data rate and extra coverage area. This can be achieved with the help of multiple input multiple...