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71.
Reconstruction of the “Neues Museum” in Berlin – structural design pro preservation of historic buildings. “While no work can be understood without knowledge of its technology, no technology can be understood without knowledge of the work, either” [1]. The reconstruction of the “Neues Museum” in Berlin is a great challenge for all participants in Adorno's terms. Historical structures, especially arched components, usually have amazing bearing capacities. It is rarely possible to verify these only by calculation. Two examples will show how calculation and experiment complement each other in analyzing the load capacity. Thus historical structure components can be admitted to modern utilisation. 相似文献
72.
Ochratoxin A in dried vine fruit: method development and survey 总被引:7,自引:0,他引:7
Susan MacDonald Pete Wilson Karen Barnes Andrew Damant Rob Massey Eileen Mortby Martin J. Shepherd 《Food Additives & Contaminants》1999,16(6):253-260
A method is described for the determination of concentrations of the mycotoxin ochratoxin A in dried vine fruits (currants, raisins and sultanas) using acidic methanolic extraction,immunoaffinity chromatography clean-up and HPLC determination. The limit of detection was estimated as 0.2mug/kg, and recoveries of 63-77% were achieved at 5mug/kg. HPLC-mass spectrometric confirmation of the identity of ochratoxin was obtained. Ochratoxin A and aflatoxins were determined in 60 samples of retail dried vine fruits purchased in the United Kingdom. Ochratoxin A was found in excess of 0.2mug/kg in 19 of 20 currant, 17 of 20 sultana and 17 of 20 raisin samples examined, an overall incidence of 88% . The maximum level found was 53.6mug/kg. No aflatoxin was found in any sample analysed, using a method with a detection limit of 0.2mug/kg for each of aflatoxin B1, B2, G1 and G2. 相似文献
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74.
Construction and optimization of a CC49-based scFv-beta-lactamase fusion protein for ADEPT 总被引:1,自引:0,他引:1
Roberge M Estabrook M Basler J Chin R Gualfetti P Liu A Wong SB Rashid MH Graycar T Babé L Schellenberger V 《Protein engineering, design & selection : PEDS》2006,19(4):141-145
CC49 is a clinically validated antibody with specificity for TAG-72, a carbohydrate epitope that is over-expressed and exposed on a large fraction of solid malignancies. We constructed a single chain fragment (scFv) based on CC49 and fused it to beta-lactamase. The first generation fusion protein, TAB2.4, was expressed at low levels in Escherichia coli and significant degradation was observed during production. We optimized the scFv domain of TAB2.4 by Combinatorial Consensus Mutagenesis (CCM). An improved variant TAB2.5 was identified that resulted in an almost 4-fold improved expression and 2.5 degrees higher thermostability relative to its parent molecule. Soluble TAB2.5 can be manufactured in low-density E.coli cultures at 120 mg/l. Our studies suggest that CCM is a rapid and efficient method to generate antibody fragments with improved stability and expression. The fusion protein TAB2.5 can be used for antibody directed enzyme prodrug therapy (ADEPT). 相似文献
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78.
An alternative way to process data from polarization measurements for fuel cell model validation is proposed. The method is based on re‐ and subsampling of I–V data, with which repetitive estimations are obtained for the model parameters. This way statistics such as standard deviations and correlations between the parameters may be experimentally derived. Histograms may also be produced, approximating the probability distributions that they follow. Two experimental case studies are discussed. In the first case, observations are made on the behavior of the parameter values for two mathematical models. As the number of data points (measurement points) employed in the estimation of the parameters increases, parameters with high variances converge to specific values. On the contrary, parameters with small variances diverge linearly. The parameters' histograms do not usually follow normal distributions rather they show a connection between the number of peaks in the graphs and correlations of the parameters. The second case study is an application on a fast degraded SOFC button cell, where the values and the histograms of the parameters are compared before and after degradation. 相似文献
79.
Setia R Smith P Marschner P Gottschalk P Baldock J Verma V Setia D Smith J 《Environmental science & technology》2012,46(3):1624-1631
Soil organic carbon (SOC) models are used to predict changes in SOC stocks and carbon dioxide (CO(2)) emissions from soils, and have been successfully validated for non-saline soils. However, SOC models have not been developed to simulate SOC turnover in saline soils. Due to the large extent of salt-affected areas in the world, it is important to correctly predict SOC dynamics in salt-affected soils. To close this knowledge gap, we modified the Rothamsted Carbon Model (RothC) to simulate SOC turnover in salt-affected soils, using data from non-salt-affected and salt-affected soils in two agricultural regions in India (120 soils) and in Australia (160 soils). Recently we developed a decomposition rate modifier based on an incubation study of a subset of these soils. In the present study, we introduce a new method to estimate the past losses of SOC due to salinity and show how salinity affects future SOC stocks on a regional scale. Because salinity decreases decomposition rates, simulations using the decomposition rate modifier for salinity suggest an accumulation of SOC. However, if the plant inputs are also adjusted to reflect reduced plant growth under saline conditions, the simulations show a significant loss of soil carbon in the past due to salinization, with a higher average loss of SOC in Australian soils (55 t C ha(-1)) than in Indian soils (31 t C ha(-1)). There was a significant negative correlation (p < 0.05) between SOC loss and osmotic potential. Simulations of future SOC stocks with the decomposition rate modifier and the plant input modifier indicate a greater decrease in SOC in saline than in non-saline soils under future climate. The simulations of past losses of SOC due to salinity were repeated using either measured charcoal-C or the inert organic matter predicted by the Falloon et al. equation to determine how much deviation from the Falloon et al. equation affects the amount of plant inputs generated by the model for the soils used in this study. Both sets of results suggest that saline soils have lost carbon and will continue to lose carbon under future climate. This demonstrates the importance of both reduced decomposition and reduced plant input in simulations of future changes in SOC stocks in saline soils. 相似文献
80.
D.J. Pete J.B. Helonde A.V. Vairagar S.G. Mhaisalkar 《Journal of Electronic Materials》2012,41(3):568-572
Electromigration-induced void evolution in various dual-inlaid copper (Cu) interconnect structures was simulated by applying
a phenomenological model assisted by Monte Carlo-based simulations, considering the redistribution of heterogeneously nucleated
voids and/or pre-existing vacancy clusters at the Cu/dielectric cap interface during electromigration. The results indicate
that this model can qualitatively explain the electromigration-induced void evolution observed during experimental in situ secondary-electron microscopy (SEM) investigations as well as in various other reported studies. The electromigration mechanism
in Cu interconnect structures and differences in the peculiar electromigration-induced void evolution in various dual-inlaid
Cu interconnect structures can be clearly understood based on this model. These findings warrant reinvestigation of technologically
important electromigration mechanisms by developing rigorous models based on similar concepts. 相似文献