Temperature Measurement Deviation during Annealing of Multiphase Steels

A pyrometric analysis of the temperature of continuous annealed strip material is an essential component of industrial production. However, despite calibration, the development of composition-dependent oxides during annealing prevents an accurate pyrometric measurement of actual strip temperature. An Al-based and a Si-based transformation induced plasticity (TRIP)-assisted steel were pyrometrically analyzed during annealing under a reducing atmosphere (5 pct H₂ and 95 pct Ar). Oxide development on both steels led to a deviation between pyrometer readings and simultaneous thermocouple measurements. The developing oxides influenced the pyrometer readings to different extents because of unique emissivities and different growth kinetics.     

Metallschichten für langlebige Strukturen

For the steady growing of the miniaturisation in the interconnection technique new basic materials with improved quality must be available. The new generation for the flex materials affords high reliability for many applications that are characterized for example by high temperature, high humidity and aggressive chemicals surroundings.     

Study of the structural,thermodynamic and cyclic effects of vanadium and titanium substitution in laves-phase AB2 hydrogen storage alloys

The substitution of the high-purity and expensive raw materials vanadium (V) and titanium (Ti) by their low-cost, low-purity alternatives ferrovanadium (FeV) and Ti sponge in Ti_0.98Zr_0.02V_0.43Fe_0.09Cr_0.05Mn_1.5 was investigated and the microstructural, thermodynamic and cyclic properties were tested of these compounds. Four different samples were prepared and studied: one material prepared with high-purity V and Ti, a second one prepared with FeV in substitution for V and Fe, a third prepared with Ti sponge in substitution for Ti, and a fourth prepared with FeV and Ti sponge in substitution for V, Fe and Ti. The substitution of Ti with Ti sponge and of V and Fe by FeV had negligible effects on the microstructural properties. 2.0 mass% H were absorbed in both the pristine (high-purity V and Ti) material and after replacing Ti by Ti sponge. Substitution of V by FeV reduced the initial hydrogen absorption capacity to approximately 1.7 mass%. All materials exhibited equilibrium hydrogen absorption and dissociation pressures of ca. 1.5 MPa. They reversibly stored 1.8 mass% H for both the pristine and Ti-substituted samples and 1.6 mass% H after substitution of V and Fe by FeV or after substitution of V, Fe and Ti by FeV and Ti sponge, respectively.Long-term cyclic experiments over 1000 de-/hydrogenation pressure swing cycles were performed for the pristine material and after substitution of V, Fe and Ti by FeV and Ti sponge, respectively. Both materials exhibited similar activation and degradation behavior upon cycling. A reversible capacity of 1.5 mass% H was recorded for the pristine material after 1000 cycles, and 1.4 mass% H were reversibly stored in the material prepared with FeV and Ti sponge subjected to 1000 cycles. The raw material cost to store an equal amount of hydrogen can be reduced by 83% when V and Ti are substituted by FeV and Ti sponge.     

Antibiotic susceptibility of bacteria isolated from pasteurized milk and characterization of macrolide-lincosamide-streptogramin resistance genes

The presence of antibiotic-resistant bacteria in pasteurized milk was detected by plating 18 milk samples on selective media containing beta-lactams, macrolides, or a glycopeptide. Most samples contained gram-positive bacteria that grew on agar plates containing oxacillin, erythromycin, and/or spiramycin. The disk-diffusion method confirmed resistance to erythromycin and/or spiramycin in 86 and 65% of the coryneform bacteria and Micrococcaceae tested, respectively. PCR and sequence analysis revealed the presence of an ermC gene in 2 of the 25 Micrococcaceae strains investigated for their resistance to erythromycin and/or spiramycin. None of the 14 corynebacteria strains resistant to erythromycin and/or spiramycin harbored the erm(X) gene. No gene transfer could be demonstrated between the two erm(C) staphylococcal isolates and recipient strains of Enterococcus faecalis JH2-2 or Staphylococcus aureus 80CR5.     

Impact of Crude Oil Quality on the Refining Conditions and Composition of Nutraceuticals in Refined Palm Oil

Palm oil is the major vegetable oil used worldwide due to its unique properties. The effect of crude palm oil acidity on the final free fatty acids (FFA) content, neutral oil loss (NOL), and nutraceutical compounds, such as carotenes, total tocols (tocopherols and tocotrienols), squalene, and phytosterols was investigated. A central composite design was employed to study the influence of the refining conditions: temperature (200 to 260 °C), steam percentage (0.5% to 3.5%), and initial FFA content (2.2% to 6.0%) on the quality of the refined product. The results revealed that initial palm oil acidity is a statistically important parameter to obtain commercially acceptable values for final FFA content. The increase of temperature presented the most important effect on the reduction of all nutraceutical compounds. The highest tocopherols (88%), phytosterols (98%), and squalene retention (84%) was obtained when applying the mildest temperature (200 °C). From the experimental results, 3 equations were generated enabling the prediction of the free fatty acids content, the tocols content, and the losses of neutral oil. Therefore, this work contributes to the understanding and optimization of the process for the production of palm oil with high nutraceutical quality and low free fatty acid contents.     

Atmospherc deposition of organochlorine compounds to remote high mountain lakes of Europe

Bulk deposition samples were taken near three mountain lakes located in the Pyrenees (Estany Redó), Alps (Gossenk?llesee), and Caledonian Mountains (Ovre Ne?dalsvatn) for evaluation of the atmospheric deposition load of organochlorine compounds (OC), namely, polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), and endosulfans, in the remote European high mountain areas. The compounds of present use in agriculture, namely, endosulfans and gamma-HCH, exhibit large differences in mean deposition fluxes between the three sites. They occur in large amounts in Estany Redó (340 and 430 ng m(-2) month(-1) for endosulfans and gamma-HCH, respectively), reflecting the impact of agricultural activities in southern Europe. This lake showed also the highest proportion of the more labile endosulfan isomers (alpha and beta = 82%) whereas only the most recalcitrant species, endosulfan sulfate, was found in Ovre Ne?dalsvatn. In contrast, the OC whose use is now banned exhibit a more uniform geographic distribution with deposition fluxes of 31-40, 30-100, and 1.4-15 ng m(-2) month(-1) for alpha-HCH, PCBs, and HCB. Both compounds of present and past use exhibit a clear seasonal pattern, with higher deposition in the warm periods, which is consistent with enhanced volatilization at higher temperatures. In the case of the agricultural pesticides it may also reflect higher use during application periods. The OC distributions in the atmospheric deposition of the three sites are rather uniform and highly enriched in compounds with volatilities larger than 0.0032 Pa. However, more than 90% of these compounds are not retained in the lake waters or sediments. Comparison of OC composition in atmospheric and sedimentary deposition evidences a selective trapping of the less volatile compounds. Trapping efficiencies increase at decreasing air temperatures of the lacustrine systems.     

Comparison of potato varieties between seasons and their potential for acrylamide formation

BACKGROUND: Acrylamide is a probable human carcinogen produced during food preparation, including frying of potato products. The aim of this study was to investigate the impact of seasonal variation on tuber composition and its acrylamide generation potential. RESULTS: The chemical composition of potato varieties used respectively for French fry (Bintje and Ramos) and crisp (Lady Rosetta and Saturna) production was studied throughout a storage period of 9 months during two growing seasons (2003 and 2004), in addition to their acrylamide generation potential during preparation of French fries. A significant impact of variable climatological conditions on the reducing sugar, dry matter, total free amino acid and free asparagine contents of tubers was observed. Exceptionally warm summers gave rise to a lower reducing sugar content (expressed on a dry matter basis) and thus a lower susceptibility to acrylamide generation during frying. CONCLUSION: It cannot be excluded that potato growers and the potato‐processing industry are confronted with some harvests that are more prone to acrylamide generation than others owing to climatological variability, thus confirming the importance of a multifactorial approach to mitigate acrylamide generation in potato products. Copyright © 2007 Society of Chemical Industry     

A statistical fatigue model covering the tension and compression Wöhler fields

A statistical fatigue model to predict the Wöhler field for any combination of _σmin${\sigma }_{min}$, _σmax${\sigma }_{max}$ or R=_σmin/_σmax$R={\sigma }_{min}/{\sigma }_{max}$ is presented. The model extends an existing model to the case of _σmax${\sigma }_{max}$ being tension and _σmin${\sigma }_{min}$ being tension or compression, and is derived based on physical, statistical and compatibility conditions, thus, eliminating the selection of arbitrary functions. The main tool to derive the model is a functional equation, which allows obtaining the most general model satisfying all the stated conditions. In particular, the regression formula for the _σmax${\sigma }_{max}$–logN$logN$ field for fixed R$R$ values is analyzed. A particular and powerful model is selected and its main properties are derived. This model is applied to some real data to illustrate its applicability to practical problems. The results seem to be very promising, especially because the model, due to its physical and statistical constraints, appears to be very robust and with a high capacity to detect outliers.