Data‐Driven Analysis of Results from Blast Furnace Tuyere Core Drillings

Due to the extremely hostile environment in the lower part of the ironmaking blast furnace, where three different phases exist and interact at high temperatures, direct measurements of the prevailing conditions are not available. Tuyere core drillings reveal information about both physical and chemical conditions at the high temperature region. In this paper some results from drillings performed relatively regularly at an industrial blast furnace are analysed and correlated with cyclic changes detected in the furnace hearth lining temperatures. The analysis s based on the lengths of the different zones, such as raceway, bird's nest and deadman, that can be detected from the drill core. The relation between the zone lengths and hearth state derived from the thermocouple readings is modelled and studied with neural networks using different combinations of the measured zone lengths as inputs. The final model can be used to study the relationship between the examined variables and also to quickly classify the hearth state on the basis of future core drillings.     

Slow initiation by tert-butoxybenzenes in living cationic polymerization of isobutylene

Summary tert-Butoxybenzenes including the 4-substituted derivatives of anisole, toluene and p-chlorobenzene have been synthesized and studied as initiators in combination with TiCl₄ for polymerization of isobutylene (IB) in CH₂Cl₂/methylcyclohexane (MeCHx) solvent mixtures at -78°C. Living polymerizations with slow initiation were observed by the allmonomer-in (AMI) and incremental monomer addition (IMA) techniques, and polymers with narrow molecular weight distribution (MWD) (M_w/M_n>1.1) were obtained under certain conditions. Aging of the initiating system prior to charging the monomer does not improve the initiating efficiency. It has been found that the initiating efficiency can be increased by increasing the solvent polarity, however, the relative volume of CH₂Cl₂ is limited in order to avoid polymer precipitation and bimodal MWD.     

Comparison of methane production by co-digesting fruit and vegetable waste with first stage and second stage anaerobic digester sludge from a two stage digester

Fruit and vegetable waste (FVW) was co-digested with first stage (FSS) and second stage anaerobic digester sludge (SSS) separately, over the course of 10 days, in batch reactors. Addition of FVW significantly increased the methane production in both sludges. After 10 days of digestion FSS + FVW produced 514 ± 57 L CH(4) kg VS(-1)(added) compared with 392 ± 16 L CH(4) for the SSS + FVW. The increased methane yield was most likely due to the higher inoculum substrate ratio of the FSS. The final VS and COD contents of the sewer sludge and FVW mixtures were not significantly different from the control values suggesting that all of the FVW added was degraded within 10 days. It is recommended that FVW be added to the first stage of the anaerobic digester in order to maximize methane generation.     

MALDI MS peptide mapping performance by in-gel digestion on a probe with prestructured sample supports

Matrix-assisted laser desorption/ionization (tandem) mass spectrometry (MALDI MS) is widely used in protein chemistry and proteomics research for the identification and characterization of proteins isolated by polyacrylamide gel electrophoresis. In an effort to minimize sample handling and increase sample throughput, we have developed a novel in-gel digestion protocol where sample preparation is performed directly on a MALDI probe with prestructured sample support. The protocol consists of few sample-handling steps and has minimal consumption of reagents, making the protocol sensitive, timesaving, and cost-efficient. Performance of the on-probe sample preparation protocol was demonstrated by analysis of a set of rat liver proteins obtained from a fluorescently stained (Cy3 and SyproRuby) two-dimensional polyacrylamide gel. The success rate of protein identification by on-probe tryptic digestion and MALDI peptide mass mapping was 89%. The on-probe in-gel digestion procedure provided superior sensitivity and peptide mass mapping performance as compared to our standard in-gel digestion protocol. The on-probe digestion technique resulted in significantly improved amino acid sequence coverage of proteins, mainly due to efficient recovery and detection of large (>1.5 kDa) hydrophobic peptides. These observations indicate that numerous tryptic peptides are lost when using the standard in-gel digestion methods and sample preparation techniques for MALDI MS. This study also demonstrates that the on-probe digestion protocol combined with MALDI tandem mass spectrometry provides a robust platform for proteomics research, including protein identification and determination of posttranslational modifications.     

Role of dietary patterns for dioxin and PCB exposure

Dietary patterns were related to intake and blood concentrations of polychlorinated dibenzo‐p‐dioxins and dibenzofurans (PCDD/PCDFs), dioxin‐like polychlorinated biphenyls (dl‐PCBs) and selected non‐dioxin‐like‐PCBs (ndl‐PCBs). Intake calculations were based on an extensive food frequency questionnaire and a congener‐specific database on concentrations in Norwegian foods. The study (2003) applied a two‐step inclusion strategy recruiting representative (n=73) and high consumers (n=111) of seafood and game. Estimated median intakes of sum PCDD/PCDFs and dl‐PCBs of the representative and high consumers were 0.78 and 1.25 pg toxic equivalents (TEQ)/kg bw/day, respectively. Estimated median intakes of ndl‐PCBs (sum chlorinated biphenyl (CB)‐28, 52, 101, 138, 153, 180) were 4.26 and 6.40 ng/kg bw/day. The median blood concentrations of PCDD/PCDFs/dl‐PCBs were 28.7 and 35.1 pg TEQ/g lipid, and ndl‐PCBs (sum of CB‐101, 138, 153 and 180) 252 and 299 ng/g lipid. The Spearman correlations between dietary intake and serum concentration were r=0.34 (p=0.017) for dl‐compounds and r=0.37 (p<0.001) for ndl‐PCBs. Oily fish was the major source of dl‐compounds and ndl‐PCBs in high and representative consumers. Four dietary patterns were identified by principal component analysis. Two were related to high intakes, one dominated by oily fish ((Ω‐3)), the other by fish liver and seagull eggs (“northern coastal”). Only the latter was closely associated with high blood concentrations of dioxins and PCBs.     

Characteristics of radial growth and stable isotopes in a single oak tree to be used in climate studies

In this study we have analyzed the variability of tree-ring widths and stable isotopes (delta(13)C and delta(18)O) of a single sessile oak tree (Quercus petraea (Matt.) Liebl.) since these parameters are critical in reconstructing the environment, particularly climatic conditions. Tree rings were separated into early- and latewood (EW(t); LW(t)), tree ring (TR(t)), and transfer tree ring (TTR(t), the latter being the latewood plus the earlywood of the subsequent year. Mean sensitivity, simple correlation, partial correlation and autocorrelation analyses were applied to describe data and relationships. Although this research focused on a single tree, the results compared well with average site data. Widths and delta(18)O values showed generally low autocorrelation for all tree-ring components, whereas delta(13)C revealed highly significant autocorrelations for most tree-ring components. Mean sensitivity of the standardized values turned out to be high for delta(18)O, marginally lower for width and the lowest for delta(13)C. Correlation analyses have proven that the relationships within the tree-ring widths or within the isotope parameters are much stronger than across widths and isotope parameters. The study demonstrates the unique potential of all measured tree-ring data to be used as climate proxies.     

Drinking Water Production from Well Water with High Sulfur and Sulfur Bacteria Content

Problems with treatment of Ahaste well water (Audru Parish, P?rnu County, Estonia) were studied in field conditions. The groundwater contains a significant amount of sulfur, from which at pH = 7.5–8.0 about 70–90% is in the form of hydrogen sulfide ion and 30–10% in the form of dissolved H2S. After aeration in the summer, this water formed an unknown slimy microbial mass with a distinct sulfuric odor, which clogged the aeration tanks, catalytic filters, and even the distribution network up to the consumers. After laboratory analyses, it was established that this unknown microbial mass is obviously the filiform sulfur bacteria Thiothrix, together with particles of free sulfur. It was found that this mass formed during enrichment under warm conditions using air as the oxidizer. Under these conditions, elemental sulfur was liberated and created favorable conditions for the Thiothrix to thrive using the elemental sulfur as their food source. A new treatment technology for this well water was developed using ozone as a strong oxidant/disinfectant, followed by filtration through an Everzit-Special, a material, which besides filtration, partially behaves as an adsorbent. The capital and operation costs of the new technology were estimated.