Quantifying technological aspects of process sustainability: a thermodynamic approach

Thermodynamic analysis has greatly helped to compare and to improve the energy efficiency of all kinds of technological processes, and recently we have also attempted to analyse some important biochemical processes under intracellular conditions. This work has pointed to some key strategies on sustainable process operation, such as the exceptionally high thermodynamic efficiencies of chemical and solar energy conversion in living cells.From this it was expected that the sustainability strategies of specific biochemical processes and those of the ecosphere as a whole could be of guidance to current technological processes, especially now that there is a growing demand from government and industry to effectively deal with sustainability aspects in process analysis. Our focus on this issue has led to methodologies to quantify technological aspects of sustainability by making use of thermodynamic principles. Three indicators were constructed to express three technological aspects of process sustainability. First, an indicator for the sustainability of resource utilization considers the thermodynamic input and the availability the resources used in the process. Secondly, an efficiency indicator focuses on the conversion and loss of thermodynamic quantities in the process itself. Thirdly, an indicator for environmental compatibility takes into account the thermodynamic input required to prevent possible negative side effects of the process, such as global warming or water pollution. The three indicators are used to reflect on (un)sustainable characteristics of current technological processes compared to biochemical processes. Finally, we address the drawbacks of combining indicator values to express overall sustainability.     

A Study of The Moisture-Uptake Kinetics of a Hygroscopic Pharmaceutical Powder

The moisture-uptake kinetics of a hygroscopic powder, sodium heparin contained in a cylindrical container, was determined using a novel moisture-uptake measuring device under a constant convective air flow. The amount of moisture uptake increased with the increase in the relative humidity of the air. The effect of powder-bed height on the total amount of moisture uptake was found to be significant only at the highest relative humidity (75%) evaluated in this study. However, the percent of weight increase of the powder as a result of moisture uptake decreases as the height of the powder bed increases. The results of this study are explained by the dynamic nature of the moisture-uptake process associated with the instrument.     

Digital implementation of bus clamped space vector modulation

Space vector modulation has recently become a popular PWM method of supplying a high performance drive. An adaptation of SVM modulation is presented here. This system is called bus clamped space vector modulation. This method has some practical advantages when compared to normal SVM. These include a reduced average switching frequency, easy digital implementation and asynchronous control and switching frequencies     

Limited expansion of the (CAG)n repeat of the Huntington gene: a premutation (?)

Pantoprazole is a specific inhibitor of the H+/K(+)-ATPase of the gastric parietal cell. The dose-dependency of a range of pantoprazole pharmacokinetic characteristics was studied. Twelve healthy male subjects were given 10, 20, 40 and 80 mg pantoprazole intravenously according to a randomized, single blind, 4-period change-over scheme. The area under the concentration vs time curve (AUC) and the maximum serum concentration (Cmax) showed a linear increase in line with the dose. Apparent volume of distribution (Vd area), clearance (Cl) and terminal half-life (t1/2) were independent of the dose. The dose-independent elimination of pantoprazole was attributed to the lack of interaction of the drug with cytochrome P450. In clinical practice, a good predictable response, as well as a low potential for interaction with other drugs might be expected.     

Psychopathy and alexithymia in female offenders.

Determined the comorbidity of psychopathy and alexithymia in 37 female inmates of a medium-security prison. The authors also investigated the association between psychopathy and alexithymia with the use of affective language in response to questions about an emotional event, and with their propensity for violence. The extent of psychopathy and alexithymia were assessed with the Hare Psychopathy Checklist—Revised (PCL-R) and the Toronto Alexithymia Scale (TAS), respectively. Using standard cutoff scores, 30% were identified as psychopaths, and 32% as alexithymics. Three Ss were both psychopaths and alexithymics. The correlation between PCL-R and TAS total scores was not significant, but the socially deviant impulsive factor of the PCL-R significantly correlated with the TAS items that reflect inability to discriminate feelings and bodily sensations. Alexithymia, but not psychopathy, was negatively related to measures of affective speech content. Both psychopathy and alexithymia were associated with a history of violence. In spite of several manifest similarities, psychopathy and alexithymia appear to be different clinical constructs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Job demands and worker health: Three-dimensional reexamination of the relationship between person€nvironment fit and strain.

The most influential study of the person–environment (P–E) fit approach to stress was conducted by J. R. French et al (1982). Unfortunately, this study operationalized fit using various transformations of difference scores, thereby introducing numerous substantive and methodological problems. In the present study, the authors reanalyze data from French et al, using a procedure described by J. R. Edwards (in press) that avoids problems with difference scores and captures the underlying 3-dimensional relationship between environment, person, and strain. Results resolve ambiguities in the French et al findings and identify relationships between environment, person, and strain that, although consistent with P–E fit theory, cannot be adequately represented by fit measures such as those used by French et al. Implications for P–E fit research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distribution and Fate of Escherichia coli in Lake Michigan Following Contamination with Urban Stormwater and Combined Sewer Overflows

Escherichia coli distribution and persistence in nearshore Lake Michigan were assessed following heavy rains and sanitary sewer overflow (SSO) and combined sewer overflow (CSO) events over a 5-year period, including an 18-day period following 25.4 cm of rainfall in which intensive studies were conducted following multiple CSO and SSO events. E. coli levels in the Milwaukee estuary and harbor following SSO and CSO events ranged from 10⁴ to nearly 10⁵ CFU/100 mL, which were significantly higher (p ≤ 0.05) than levels following rainfall alone. Sites outside of the breakwall but within the contamination plume (e.g., within 2 km of the harbor) were an order of magnitude lower. Locations 2–5 km from the harbor ranged from below detection limits, of < 1 to 5 CFU/100 mL. E. coli levels corrected for dilution based on specific conductivity measurements were lower than what would be expected for loss due to dilution alone, suggesting a combination of die-off and dilution, were responsible for the rapid disappearance of these organisms outside of the harbor. E. coli and fecal coliforms measured concurrently demonstrated that fecal coliforms could be recovered longer than E. coli in the open waters of the lake. E. coli isolated directly from sewage treatment plant influent were found to have a marked increase in antibiotic resistance traits for ten antibiotics commonly used in the human population compared with isolates from two animal sources of fecal pollution. However, E. coli obtained from sewage impacted water (n = 2,513) and from stormwater impacted water (n = 1,465) collected the previous year when there were no sewage overflows, were found to have no significant difference (p < 0.05) in the frequency of resistance when comparing the two conditions. E. coli survival characteristics and population dynamics are most likely influenced by multiple factors in complex systems such as the watershed/estuarine/lake environments of the Great Lakes.     

Impact of Preferential P-Diffusion Along the Grain Boundaries on Fine-Grained Polysilicon Solar Cells

Thin-film polysilicon solar cells are a promising low-cost alternative for bulk silicon solar cells due to their reduced material thickness. Recently, we showed that the use of an amorphous silicon/polycrystalline silicon heterojunction emitter instead of a diffused homojunction emitter led to a boost in the open-circuit voltage by 90 mV. Now, we present a full evidence that shows that this improvement is related to the absence of dopant smearing along the grain boundaries. By using scanning spreading resistance microscopy, we found an enlargement of the junction area by a factor of five in case of a homojunction. The tips of the dopant spikes represent lowly doped areas with an enhanced recombination.