Dose-response feeding study of short chain chlorinated paraffins (SCCPs) in laying hens: effects on laying performance and tissue distribution, accumulation and elimination kinetics

Technical short chain chlorinated paraffins (C10-C13 with 60% chlorine) were fed to 93 laying hens from 24 to 32 weeks of age in increasing concentrations of up to 100 mg/kg feed. No significant influence on health, relative organ weights or performance (laying intensity, egg weight, feed consumption) was noted. The chlorinated paraffin content of the tissues was linearly related to the concentration of short chain paraffins of the feed. The highest concentrations were found in abdominal fat, egg yolk and fatty tissues. Breast muscle, egg albumen and bile fluid contained minimal or no residues. Less than 1% of the chlorinated paraffins ingested were incorporated into the body (without head, feet, gut and feathers), whereas about 1.5% were eliminated with the egg yolk and 30% were excreted with urine and faeces. A six-week kinetic depuration study revealed a biphasic elimination with half-lifes of 4-40 min (liver, kidneys, legs, fat, blood) for the initial rapid phase, and 15-30 days (blood, fat, liver, yolk, kidneys, legs) for the terminal slow phase.     

Silage fermentation of fish or fish waste products with lactic acid bacteria

Silage fermentation of minced fish and fish offal after inoculation with cereals prefermented with Pediococcus acidilactici and Lactobacillus plantarum initiates a rapid fall in pH to below 4.5 within 30 h, and the content of competing gram-negative fermenters and fish pathogens, such as Vibrio anguillarum and Aeromonas salmonicida, is eliminated. The addition of 0.1% sorbic acid inhibits the growth of yeasts during the initial fermentation period and during storage but does not affect the lactic acid fermentation. Degradation of nitrogen components proceeds during storage and is manifested as an increase in volatile basic nitrogen compounds, amino acids and peptides. These substances increase the pH and/or force the bacteria to produce more acid. The rate of production of these basic substances is mainly temperature-dependent and cannot be attributed to microbial activity. The proteolytic activity is mainly caused by tissue proteases (e.g., cathepsins) and, to a lower degree, by gut proteases. It is doubtful whether fish fermentation can be utilised on an industrial scale without improving the technique. Such improvements consist of the selection and use of psychotrophic lactic acid fermenters and commercially acceptable inhibitors of proteolytic activity and yeast growth.     

Development of an event-specific detection method for genetically modified rice Kefeng?6 by quantitative real-time PCR

The genetically modified (GM) rice Kefeng?6 has gained resistance against several rice pests by inserting the cpti and cry1Ac genes. As this transgenic line is not approved for import, processing and cultivation in the European Union (EU), sensitive and specific detection methods need to be available to monitor any illegal presence of Kefeng?6 in food products within the EU. The aim of this study was to develop and validate an event-specific detection method by means of quantitative real-time PCR (qPCR) for the detection of Kefeng?6 in foodstuff. A primer pair and hydrolysis probe were designed according to the right border junction sequence of the transgene. The qPCR assay was validated according to the ENGL/EURL-GMFF guidelines for GMO testing and is presented according to the MIQE guidelines. The in-house validation process resulted in a limit of detection of 5 DNA copies of the transgene with confidence intervals (95?%) between 0.07 and 0.52, a PCR efficiency of 105?% and a correlation coefficient (R ²) value of 0.9997. The specificity of the assay was tested by end-point PCR, gel electrophoresis and subsequent sequencing of the PCR products. By testing DNA of several GM and non-GM crops, cross reactivity of the assay was not observed. Further, 35 food products were analyzed for the presence of Kefeng?6 by means of the event-specific detection method. For 9 out of 35 samples, PCR products for Kefeng?6 DNA were observed.     

The Adhesion‐Enhanced Contact Electrification and Efficiency of Triboelectric Nanogenerators

In the present work, the contact electrification of polymers that differ in adhesion strength is studied. Electrical current is measured along with adhesion in macroscale contacting‐separation experiments. Additionally, local adhesion and roughness are studied with atomic force microscopy to get deeper insight into relations between surface properties and electrification. Measurements reveal that higher surface charge is formed on more adhesive surfaces, thus confirming covalent bond cleavage as a mechanism for contact electrification of polymers. Investigated materials possess enhanced contact electrification making them attractive candidates for the conversion of mechanical energy to electrical in triboelectric nanogenerator devices.     

Spectroscopic and chemical-kinetic analysis of the phases of HCCI autoignition and combustion for single- and two-stage ignition fuels

The temporal phases of autoignition and combustion in an HCCI engine have been investigated in both an all-metal engine and a matching optical engine. Gasoline, a primary reference fuel mixture (PRF80), and several representative real-fuel constituents were examined. Only PRF80, which is a two-stage ignition fuel, exhibited a “cool-flame” low-temperature heat-release (LTHR) phase. For all fuels, slow exothermic reactions occurring at intermediate temperatures raised the charge temperature to the hot-ignition point. In addition to the amount of LTHR, differences in this intermediate-temperature heat-release (ITHR) phase affect the fuel ignition quality. Chemiluminescence images of iso-octane show a weak and uniform light emission during this phase. This is followed by the main high-temperature heat-release (HTHR) phase. Finally, a “burnout” phase was observed, with very weak uniform emission and near-zero heat-release rate (HRR). To better understand these combustion phases, chemiluminescence spectroscopy and chemical-kinetic analysis were applied for the single-stage ignition fuel, iso-octane, and the two-stage fuel, PRF80. For both fuels, the spectrum obtained during the ITHR phase was dominated by formaldehyde chemiluminescence. This was similar to the LTHR spectrum of PRF80, but the emission intensity and the temperature were much higher, indicating differences between the ITHR and LTHR phases. Chemical-kinetic modeling clarified the differences and similarities between the LTHR and ITHR phases and the cause of the enhanced ITHR with PRF80. The HTHR spectra for both fuels were dominated by a broad CO continuum with some contribution from bands of HCO, CH, and OH. The modeling showed that the CO+O→CO₂+hν reaction responsible for the CO continuum emission tracks the HTHR well, explaining the strong correlation observed experimentally between the total chemiluminescence and HRR during the HTHR phase. It also showed that the CO continuum does not contribute to the ITHR and LTHR chemiluminescence. Bands of H₂O and O₂ in the red and IR regions were also detected during the HTHR, which the data indicated were most likely due to thermal excitation. The very weak light emission in the “burnout” phase also appeared to be thermal emission from H₂O and O₂.     

Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids

Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10–60 min. Nonetheless, after 10 d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10 d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, would require a pre-leaching step lasting several days in order to be efficient.     

Heat of solidification in refractory metals studied by drop-tube experiments

A number of pure refractory metals have been investigated by drop-tube experiments. The cooling curves have been registered and theoretically analysed. A model for analysing the heat of fusion has been developed. It was found that the heat of fusion was approximately 50% of the tabulated value.     

On-line monitoring of fuel moisture-content in biomass-fired furnaces by measuring relative humidity of the flue gases

Combustion of biomass for heat and power production is continuously growing in importance, because of incentives for replacing fossil energy resources with renewable ones. In biomass combustion, the moisture content of the fuel is an essential operation parameter, which often fluctuates for biomass fuels. Variation in moisture content complicates the operation of the furnaces and results in an uncertainty in the energy content of the fuel delivered to a plant. The fuel moisture-content in a furnace may be determined either by direct measurement on the entering fuel or by measuring the moisture and oxygen contents of the flue gases deriving the moisture content of the fuel. However, reliable methods of a motivated cost for the small to medium-scale furnaces are today not available. An exception is if the furnace is equipped with flue-gas condenser, which can be used to estimate the moisture content of the flue gases. A limitation of this method is, though, that not all furnaces have flue-gas condensers and that the measured signal has an inherent time delay.In this work, measurement of the relative humidity (RH) of the flue gases from a furnace is investigated as the central component in the on-line monitoring of the moisture content of the fuel in a furnace. The method was analysed with humid air in a laboratory environment and tested for accuracy and dynamical behaviour in two biomass-fired heat-production units, one circulating fluidised-bed boiler (CFB) and one grate furnace. The results show that the method, which is easy to calibrate on site, can be used to predict the moisture content of the biomass fuel in the grate furnace with very good precision (<4% error). Furthermore, the method detects variations in moisture content of the furnace flue gases due to changes in the moisture content of the combusted fuel within the order of seconds. Since the transport time of the flue gases from the furnace to the measurement position is of the same order of magnitude, the total time for detection of a change in the moisture content of the fuel is small enough for the signal to be used to control both the fuel feed and the combustion air in a grate furnace.