Chromium speciation in coal and biomass co-combustion products

Chromium speciation is vital for the toxicity of products resulting from co-combustion of coal and biomass. Therefore, understanding of formation processes has been studied using a combination of X-ray absorption fine structure (XAFS) spectroscopy and thermodynamic equilibrium calculations. The influence of cofiring on Cr speciation is very dependent on the type of fuel. Cr(VI) contents in the investigated fly ash samples from coal and cofiring average around 7% of the total chromium. An exception is cofiring 7-28% wood for which ashes exhibited Cr(VI) concentrations of 12-16% of the total chromium. Measurements are in line with thermodynamic predictions: RE factors of Cr around 1 are in line with volatile Cr only above 1400 °C; lower Cr(VI) concentrations with lower oxygen content and Cr(III) dissolved in aluminosilicate glass. Stability of Cr(VI) below 700 °C does not correlate with Cr(VI) concentrations found in the combustion products. It is indicated that Cr(VI) formation is a high-temperature process dependent on Cr evaporation (mode of occurrence in fuel, promoted by organic association), oxidation (local oxygen content), and formation of solid chromates (promoted by presence of free lime (CaO) in the ash). CaCrO(4)(s) is a probable chemical form but, given different leachable fractions (varying from 25 to 100%), different forms of Cr(VI) must be present. Clay-bound Cr is likely to dissolve in the aluminosilicate glass phase during melting of the clay.     

A multiplex ligation detection assay for the characterization of Salmonella enterica strains

A proof of principle of a multi-target assay for genotyping Salmonella has been developed targeting 62 genomic marker sequences of Salmonella related to pathogenicity. The assay is based on multiplex ligation detection reaction (LDR) followed by customized ArrayTube? microarray detection. The feasibility of the developed assay was verified in a method comparison study with conventional PCR using 16 Salmonella 'test' strains comprising eight serovars. Subsequently, the feasibility of the LDR microarray assay was also tested by analyzing 41 strains belonging to 23 serovars. With the exception of four serovars each serovar was characterized by a unique virulence associated gene repertoire. The LDR microarray platform proved to be a convenient, rapid and easy to use tool with potential in tracing a Salmonella contamination in the food chain, for outbreak studies, and to provide data for risk assessors that support bio-traceability models.     

Influence of Temperature on the Fatigue Behaviour of Glass Fibre Reinforced Polypropylene

Abstract: The behaviour of a composite with a polymeric matrix subjected to fatigue was analysed. The study was conducted at ambient temperature, as well as at 50 and 100 °C. The material was observed to behave differently at each temperature. Furthermore, a statistical analysis was performed using Castillo’s model. Although certain similarities in behaviour were observed at ambient temperature and 50 °C, the material behaved differently at 100 °C. Structural modifications were found in the thermal analysis that justify these differences.     

Setpoint control for air heating in a church to minimize moisture related mechanical stress in wooden interior parts

The paper presents the setpoint control for air heating in a church to minimize moisture related mechanical stress in wooden interior parts, with the focus on the preservation of a monumental organ. The setpoint operation of the heating, ventilation, and air conditioning (HVAC) system is evaluated by simulation using MatLab, COMSOL and Simulink models. The main model components are presented and combined in a single integrated Simulink model: (1) a HAMBase Simulink building model for simulating the indoor temperature and relative humidity, (2) a COMSOL partial differential equation model for simulating detailed dynamic moisture transport and related mechanical stresses in the monumental wood (organ) and (3) a Simulink controller model. The main advantage of the integrated model is that it directly simulates the impact of HVAC control setpoint strategies on the indoor climate and the related mechanical stresses in wooden objects, like a monumental organ. As control strategy the limited indoor air temperature changing rate is discussed. Recommendations from international literature suggest that a limitation of the relative humidity changing rate of 2 to 5RH%/h will preserve the interior of churches. This study shows that a limitation of indoor air relative humidity changing rate of 2RH%/h can reduce mechanical stresses by a factor of 2.5, compared to maximum capacity heating.     

Genome-wide association study for milk infrared wavenumbers

Individual wavenumbers of the infrared (IR) spectra of bovine milk have been shown to be moderately to highly heritable. The objective of this study was to identify genomic regions associated with individual milk IR wavenumbers. This is expected to provide information about the genetic background of milk composition and give insight in the relation between IR wavenumbers and milk components. For this purpose, a genome-wide association study was performed for a selected set of 50 individual IR wavenumbers measured on 1,748 Dutch Holstein cows. Significant associations were detected for 28 of the 50 wavenumbers. In total, 24 genomic regions distributed over 16 bovine chromosomes were identified. Major genomic regions associated with milk IR wavenumbers were identified on chromosomes 1, 5, 6, 14, 19, and 20. Most of these regions also showed significant associations with fat, protein, or lactose percentage. However, we also identified some new regions that were not associated with any one of these routinely collected milk composition traits. On chromosome 1, we identified 2 new genomic regions and hypothesized that they are related to variation in milk phosphorus content and orotic acid, respectively. On chromosome 20, we identified a new genomic region that seems to be related to citric acid. Identification of genomic regions associated with milk phosphorus content, orotic acid, and citric acid suggest that the milk IR spectra contain direct information on these milk components. Consequently milk IR analyses probably can be used to predict these milk components, which have low concentrations in milk; this can lead to novel applications of milk IR spectroscopy for dairy cattle breeding and herd management.     

Influence of substrate treatment on the tribological properties of DLC coatings

Due to the very thin nature of DLC coatings, the substrate must carry the main part of the applied load. If the substrate has insufficient strength to carry the contact load and thus support the coating, plastic deformation will occur, leading to premature failure of the coating. The challenge to improve the properties of hard DLC coatings by thermo-chemical pre-treatment of the substrate has gained much attention in recent years, leading to a new method called duplex treatment. In the present study, a hydrogen-free hard carbon coating deposited on plasma nitrided AISI 4140 steel was investigated with respect to microhardness, residual stress, scratch adhesion and dry sliding wear resistance. The pin-on-disc results showed that nitriding of the substrate improves the wear resistance of the hydrogen-free hard carbon coating as compared to the hardened substrate. The improvement can be related to the increased load carrying capacity of the steel substrate and to improved coating to substrate adhesion.     

CHOP vs. ProMACE-CytaBOM in the treatment of aggressive non-Hodgkin's lymphomas: long-term results of a multicenter randomized trial.(PETHEMA: Spanish Cooperative Group for the Study of Hematological Malignancies Treatment, Spanish Society of Hematology)

From May 1985 to May 1989, 175 patients with previously untreated aggressive non-Hodgkin's lymphoma were randomized to receive CHOP or ProMACE-CytaBOM. Eligibility criteria included follicular large-cell diffuse small cleaved-cell, diffuse mixed, diffuse large-cell and immunoblastic lymphoma with an Ann Arbor stage II, III or IV. One hundred and forty-eight patients were evaluable. There were no significant differences between the 2 treatments in response rate (83.5% [57.5% CR] for CHOP vs. 88% [62% CR] for ProMACE-CytaBOM), time to treatment failure (29% vs. 31% at 5 yr), or overall survival (42% in both groups at 5 yr). Furthermore, there were no significant differences between the 2 regimens when response rates and outcome were analyzed for different prognostic subgroups. Toxicity was not significantly different between the 2 regimens, although only 1 patient died as result of treatment-related toxicity in the CHOP arm compared to 6 patient in the ProMACE-CytaBOM group (p = 0.126). In conclusion, in this study ProMACE-CytaBOM has not proved to be superior to CHOP in aggressive lymphomas. This trial gives support to the notion that CHOP still is the standard chemotherapy for aggressive lymphomas, and that new treatment approaches for these lymphomas should be compared to CHOP.     

Thermal tolerance of the invasive oyster Crassostrea gigas: feasibility of heat treatment as an antifouling option

Pacific oysters, Crassostrea gigas are traditionally considered shellfish of great fishery and aquaculture value. For these reasons they are introduced worldwide. Recently there has been increasing reports about the prevalence of C. gigas as biofouling organism in cooling water systems. In the absence of relevant data on the susceptibility of oysters to commonly employed antifouling techniques such as heat treatment, it was presumed that oysters would be controlled by treatment programmes directed against other major fouling organisms. The present study was carried out to test the above hypothesis, and results showed that C. gigas has an upper temperature tolerance that is much higher than other major marine fouling animals including blue mussel Mytilus edulis. Apparently, temperature regimes presently used in heat treatment of cooling water systems fouled by mussels need to be increased, if C. gigas are to be controlled effectively. Our results also indicate that previous exposure of C. gigas to sublethal high temperatures could make them more resistant to subsequent thermal treatment, an aspect that should be taken into account when heat treatment is used as a fouling control option against oyster fouling.