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71.
General trends, observations and personal viewpoints are presented on membrane processes for the water, pulp and paper, and the food industry. Thus electrodialysis, reverse osmosis and ultrafiltration are considered form their historic and economic aspects, and thoughts are advanced on how and why institutions and companies have entered this technology and which entities will be leading the development in the eighties. 相似文献
72.
Examined the effects of act- and outcome-oriented adult prohibitions on the moral judgments of 7- and 9-yr-old children. Moral dilemmas portraying children in hospital settings were presented to 32 Ss aged 6.0–9.11 yrs. The stimulus presentation contained an audiotaped adult prohibition directed at the portrayed target children: one prohibition condition (act oriented) emphasized a desired action, while the other (outcome oriented) emphasized a desired outcome. In line with predictions, the direction of moral judgments made by 7-yr-olds was influenced by the nature of the antecedent adult prohibition, with intentional judgments made under the act-oriented condition and consequential judgments under the outcome-oriented condition. Nine-yr-olds gave intentional judgments in both conditions. The results provide some support for a cognitive-developmental view of child discipline. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
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75.
Bj?rn-Ivar Klevebring Erik Bogren Rune Mahrs 《Metallurgical and Materials Transactions A》1975,6(1):319-327
A theory for determining the critical inclusion size with respect to void formation during hot working operation is presented.
The theoretical model assumes that the relationship between inclusion size (r) and number (n) is of the typen = 1/rα. Equations are deduced for the three cases α = 2,α = 3 and α = 4. The most reliable results are obtained if α equals 3 or 4. The critical inclusion size is of the order of
2.5 to 3.5 μm for strains of about 0.7.
Formerly with the Department of Ferrous Metallurgy, Royal Institute of Technology, Stockholm. 相似文献
76.
Significant identification of proteins by mass fingerprinting and partial sequencing of tryptic peptides is central to proteomics. However, peptide masses cluster with distances of approximately 1 Da. Expanding these clusters will give more peptides of unique masses, thereby identifying proteins with a higher significance. The mass clusters can be expanded downward by including more oxygen atoms in the peptides. Classic performic acid oxidation modifies three residues, Cys to CysO(3), Met to MetO(2), and Trp to TrpO(2). In this study, we compare the mass distributions of tryptic peptides computed from the predicted proteomes of Bacillus subtilis, Drosophila melanogaster, Arabidopsis thaliana, and Homo sapiens modified by oxidation, reduction, and reduction followed by carboxymethylation, carboxamidomethylation, or pyridylethylation. Forty to 46% of the eukaryotic tryptic peptides contain Cys, Met, or Trp. Additionally, the importance of mass accuracy of differentially modified tryptic peptides for significant protein identification by database searches was analyzed. The results show that performic acid oxidation gives markedly extended mass distributions at mass accuracies from +/-0.002 to +/-0.25 Da for the eukaryotes. The effect of the expanded mass distribution on significant protein identification was illustrated by searching simulated mass peak lists against the databases containing oxidized and reduced tryptic peptides. The specificity of formic acid oxidation was tested experimentally, and no general adverse effects were detected. Tryptic peptides provided a 100% sequence coverage of oxidized barley grain peroxidase by LC-MS, and the sequence coverages of oxidized and carboxymethylated bovine serum albumin were similar by MALDI-TOF MS analyses. 相似文献
77.
The influence of ammonium ions on the activity and selectivity of the electrocatalytic oxygen reduction reaction (ORR) on polycrystalline Pt was investigated in model studies under continuous mass transport, both in sulfuric and perchloric acid solutions. Ammonium was found to increase the yield of hydrogen peroxide, particularly in sulfuric acid, but also in perchloric acid solutions, and also at higher potentials (0.80–0.90 VRHE) typical for fuel cell cathode operation, which may severely impair the long-term stability of membranes and electrodes in fuel cells exposed to fuel gases and/or air containing ammonia. Adsorbed species, assigned to ammonia and nitric oxide, were identified on a Pt film electrode using in situ FTIR spectroscopy. Adsorbed nitric oxide could only be observed in perchloric acid solutions. The higher coverage of adsorbed ammonia in sulfuric acid solution is attributed to a stabilization by coadsorbed (bi-)sulfate species; the higher total coverage in this electrolyte can explain the larger effect of ammonium ions on the ORR activity and selectivity in sulfuric compared to perchloric acid solution. 相似文献
78.
Degradation kinetics of different size dextrans in a biofilm reactor were evaluated. Degradation rates of dextran standards, measured as time series of oxygen utilisation rates, decreased with increasing initial molecular weight. Removal of bulk phase total organic carbon with time was highly correlated (R2>0.99) and could be modelled with variable half-order degradation rate expressions. A power correlation between initial molecular weight and the variable half-order degradation rate coefficient was found for polymers in the range 6-500 kDa. Degradation of dextran in the colloid size range (MW>1 Mda) did not follow the same kinetics. Reductions in the observed removal rate with polymer size can be explained by the effect of reduced diffusivities of the substrate, without assuming reaction rate effects. 相似文献
79.
Rune Haubo Bojesen Christensen Graham CleaverPer Bruun Brockhoff 《Food quality and preference》2011,22(6):542-549
The A-not A protocol with sureness produce multinomial observations that are traditionally analyzed with statistical methods for contingency tables or by calculation of an R-index. In this paper it is shown that the Thurstonian model for the A-not A protocol can be written as a cumulative link model including the binormal unequal variances model. The model is extended to allow for explanatory variables and we illustrate how consumer differences can be modeled within the Thurstonian framework on a consumer study of packet soup conducted by Unilever. The extension also allows several test-product variations to be analyzed in the same model providing additional insight and reduced experimental costs. The effects of explanatory variables on the Thurstonian delta, the sensitivity (AUC), the ROC curve and the response category thresholds are discussed in detail. All statistical methods are implemented in the free R-package ordinal (http://www.cran.r-project.org/package=ordinal/). 相似文献
80.
Bjørn Rune Sørås Rogne Christian Thaulow Afrooz Barnoush 《Metallurgical and Materials Transactions A》2014,45(4):1996-2003
Micropillar compression tests were performed on martensite (M) and retained austenite (A) containing constituents formed in high-strength low-alloy steel after simulated thermal weld heat treatment. Due to the complicated fine microstructure of the constituent, the resulted stress–strain curves were further analyzed by considering the post-mortem scanning electron micrographs and the morphology of the deformation of the pillars. It was possible to obtain relevant data for the uniaxial stress–strain behavior of the M–A constituent in the studied steel. Microvickers measurements, which were converted to macroscopic yield stress by empirical relations, were compared with the micropillar compression test results. Comparison showed that these empirical relations are overestimating the obtained mechanical properties of the M–A constituents. 相似文献