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71.
Physicochemical properties and amylopectin chain profiles of cowpea,chickpea and yellow pea starches
Junrong Huang Henk A. Schols Jeroen J.G. van Soest Zhengyu Jin Ellen Sulmann Alphons G.J. Voragen 《Food chemistry》2007,101(4):1338-1345
Starches from cowpea and chickpea seeds were isolated and their properties were compared with those of commercial yellow pea starch. Amylose contents were 25.8%, 27.2%, and 31.2%, and the volume mean diameter of granules, determined in the dry state, were 15.5, 17.9, and 33.8 μm for cowpea, chickpea and yellow pea starches, respectively. All three legume starches showed a C-type X-ray diffraction pattern and two-stage swelling pattern. Amylopectin populations were isolated and the unit chain profiles were analyzed by HPLC after debranching with pullulanase. The degree of polymerization (DP) of short chain populations was about 6–50 and the populations of long chain had a DP of 50–80. Cowpea showed a lower weight ratio of short:long chains than chickpea and yellow pea starches. The larger portion of long side chains in cowpea amylopectin can be correlated with a higher gelatinization temperature, greater pasting peak and a slight difference in crystalline structure found for cowpea starch. Chickpea and yellow pea starches exhibited similarity in unit chain profile of amylopectin as well as in gelatinization temperature and pasting profile, while they differed in amylose content, particle size and syneresis. It is assumed that the chain length distribution of amylopectin has a large influence on starch properties. 相似文献
72.
de Jong Peter J.; Merckelbach Harald; Arntz Arnoud; Nijmam Henk 《Canadian Metallurgical Quarterly》1992,101(4):724
20 treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by the behavioral treatment. In addition, untreated Ss were more confident about their contingency estimates than were treated Ss. The present results fit with earlier studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Stroebe Margaret; Stroebe Wolfgang; Schut Henk; Zech Emmanuelle; van den Bout Jan 《Canadian Metallurgical Quarterly》2002,70(1):169
Two longitudinal studies assessed whether disclosure of emotions facilitates recovery from bereavement. Study 1 tested prospectively over a 2-year period whether the extent to which bereaved persons talked about their loss to others and disclosed their emotions was associated with better adjustment to the loss of a marital partner. There was no evidence that disclosure facilitated adjustment. Study 2 randomly assigned recently bereaved individuals either to the Pennebaker writing task (J. W. Pennebaker & S. K. Beall, 1986) or to no-essay control conditions. The writing task did not result in a reduction of distress or of doctors visits either immediately after the bereavement or at a 6-month follow-up. Beneficial effects were not demonstrated for bereaved persons who had suffered an unexpected loss or who at the time of the study still expressed a high need for emotional disclosure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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76.
Klánová J Diamond M Jones K Lammel G Lohmann R Pirrone N Scheringer M Balducci C Bidleman T Bláha K Bláha L Booij K Bouwman H Breivik K Eckhardt S Fiedler H Garrigues P Harner T Holoubek I Hung H MacLeod M Magulova K Mosca S Pistocchi A Simonich S Smedes F Stephanou E Sweetman A Sebková K Venier M Vighi M Vrana B Wania F Weber R Weiss P 《Environmental science & technology》2011,45(18):7617-7619
77.
Chromium speciation in coal and biomass co-combustion products 总被引:1,自引:0,他引:1
Stam AF Meij R Te Winkel H Eijk RJ Huggins FE Brem G 《Environmental science & technology》2011,45(6):2450-2456
Chromium speciation is vital for the toxicity of products resulting from co-combustion of coal and biomass. Therefore, understanding of formation processes has been studied using a combination of X-ray absorption fine structure (XAFS) spectroscopy and thermodynamic equilibrium calculations. The influence of cofiring on Cr speciation is very dependent on the type of fuel. Cr(VI) contents in the investigated fly ash samples from coal and cofiring average around 7% of the total chromium. An exception is cofiring 7-28% wood for which ashes exhibited Cr(VI) concentrations of 12-16% of the total chromium. Measurements are in line with thermodynamic predictions: RE factors of Cr around 1 are in line with volatile Cr only above 1400 °C; lower Cr(VI) concentrations with lower oxygen content and Cr(III) dissolved in aluminosilicate glass. Stability of Cr(VI) below 700 °C does not correlate with Cr(VI) concentrations found in the combustion products. It is indicated that Cr(VI) formation is a high-temperature process dependent on Cr evaporation (mode of occurrence in fuel, promoted by organic association), oxidation (local oxygen content), and formation of solid chromates (promoted by presence of free lime (CaO) in the ash). CaCrO(4)(s) is a probable chemical form but, given different leachable fractions (varying from 25 to 100%), different forms of Cr(VI) must be present. Clay-bound Cr is likely to dissolve in the aluminosilicate glass phase during melting of the clay. 相似文献
78.
Aarts HJ Vos P Larsson JT van Hoek AH Huehn S Weijers T Grønlund HA Malorny B 《International journal of food microbiology》2011,145(Z1):S68-S78
A proof of principle of a multi-target assay for genotyping Salmonella has been developed targeting 62 genomic marker sequences of Salmonella related to pathogenicity. The assay is based on multiplex ligation detection reaction (LDR) followed by customized ArrayTube? microarray detection. The feasibility of the developed assay was verified in a method comparison study with conventional PCR using 16 Salmonella 'test' strains comprising eight serovars. Subsequently, the feasibility of the LDR microarray assay was also tested by analyzing 41 strains belonging to 23 serovars. With the exception of four serovars each serovar was characterized by a unique virulence associated gene repertoire. The LDR microarray platform proved to be a convenient, rapid and easy to use tool with potential in tracing a Salmonella contamination in the food chain, for outbreak studies, and to provide data for risk assessors that support bio-traceability models. 相似文献
79.
80.
Setpoint control for air heating in a church to minimize moisture related mechanical stress in wooden interior parts 总被引:1,自引:0,他引:1
The paper presents the setpoint control for air heating in a church to minimize moisture related mechanical stress in wooden
interior parts, with the focus on the preservation of a monumental organ. The setpoint operation of the heating, ventilation,
and air conditioning (HVAC) system is evaluated by simulation using MatLab, COMSOL and Simulink models. The main model components
are presented and combined in a single integrated Simulink model: (1) a HAMBase Simulink building model for simulating the
indoor temperature and relative humidity, (2) a COMSOL partial differential equation model for simulating detailed dynamic
moisture transport and related mechanical stresses in the monumental wood (organ) and (3) a Simulink controller model. The
main advantage of the integrated model is that it directly simulates the impact of HVAC control setpoint strategies on the
indoor climate and the related mechanical stresses in wooden objects, like a monumental organ. As control strategy the limited
indoor air temperature changing rate is discussed. Recommendations from international literature suggest that a limitation
of the relative humidity changing rate of 2 to 5RH%/h will preserve the interior of churches. This study shows that a limitation
of indoor air relative humidity changing rate of 2RH%/h can reduce mechanical stresses by a factor of 2.5, compared to maximum
capacity heating. 相似文献