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981.
M. J. Callejo M. J. Gil G. Rodríguez M. V. Ruiz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1999,139(3):27-32
Continuing an investigation into the different factors affecting the quality of white pan bread and the changes taking place during storage, on the basis of instrumental determinations of firmness using compression and bending tests, this second instalment addresses the influence of adding gluten to the dough. Three types of bread were prepared using three different water contents and three proportions of added gluten each. Firmness was evaluated at 24, 48 and 72 h. Addition of gluten significantly increased flexibility and significantly decreased firmness in the bread at the higher water content levels. It also improved the keeping properties of the bread by slowing the increase in firmness with time; this effect was also higher at the higher water content levels. 相似文献
982.
A. Ruiz Celma F. López-Rodríguez F. Cuadros Blázquez 《Food and Bioproducts Processing》2009,87(4):247-253
The thin-layer infrared drying behaviour of industrial grape by-products was experimentally investigated in the temperature range from 100 to 160 °C. The drying rate was found to increase with temperature, thus reducing the total drying time. In particular, as drying temperature was raised from 100 °C up to 160 °C, the time period needed to reduce the moisture content of the sample from 204.32% down to 38.89% by weight (dry basis) decreased from 60.5 to 21 min.Using a non-linear regression (Marquart's method) together with a multiple regression analysis, a mathematical model for the thin-layer infrared drying process of wet grape residues was proposed. The values for the diffusivity coefficients at each temperature were obtained using Fick's second law of diffusion. They varied from 11.013 × 10?9 to 26.050 × 10?9 m2/s along the temperature range. The temperature dependence of the effective diffusivity coefficient was expressed by an Arrhenius type relationship. Activation energy for the moisture diffusion was determined as 19.27 kJ/mol. 相似文献
983.
Xiaole Weng Ben Perston Xue Z. Wang Isaac Abrahams Tian Lin Shoufeng Yang Julian R.G. Evans David J. Morgan Albert F. Carley Michael Bowker Jonathan C. Knowles Ihtesham Rehman Jawwad A. Darr 《Applied catalysis. B, Environmental》2009,90(3-4):405-415
Two compositions Ce0.50Zr0.39La0.04Y0.07O2−δ and Ce0.25Zr0.65La0.04Y0.06O2−δ based on ceria-zirconia solid solutions were prepared as nanopowders using a continuous hydrothermal flow synthesis reactor, followed by either freeze-drying or hotplate-drying of the slurry. Each dried nanopowder was then subjected to 10 h heat-treatment at 1000 °C, 1100 °C or 1200 °C in air (to simulate accelerated ageing). The reducibility and hydrogen consumption of the oxidised samples were measured using temperature programmed reduction (TPR) up to 1000 °C. The effects of composition, drying method and heat-treatment temperature were evaluated on the TPR profiles of the materials. The powders were further investigated using a range of analytical methods including UV/Vis spectroscopy (which yielded colour data), Raman spectroscopy, powder X-ray diffraction, BET surface area measurements and X-ray photoelectron spectroscopy (XPS). Chemometric methods were used to investigate relationships between the spectroscopic and total oxygen storage capacity (OSC) data. Principal component analysis (PCA) was used to provide a simple interpretation of the effects of various synthesis and treatment parameters on Raman spectra. Principal component regression (PCR) was used to build regression models relating the Raman spectra and the temperature of hydrogen consumption peak at several set temperatures in the TPR. The total hydrogen consumption of the materials was generally high, while the drying and heat-treatment conditions appeared to have a significant effect on the final properties of the resulting powders, such as the surface area and total oxygen storage capacity. 相似文献
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987.
Barefoot John C.; Beckham Jean C.; Haney Thomas L.; Siegler Ilene C.; Lipkus Isaac M. 《Canadian Metallurgical Quarterly》1993,8(1):3
Multiple measures of hostility were administered to middle-aged and older volunteers. There was a positive association between age and self-report measures reflecting hostile beliefs about others, including cynicism and suspiciousness. There was a weak inverse relationship between age and self-report measures of the overt expression of anger and aggression, but no association between age and measures of covert hostility was found. There was a positive relationship between age and an assessment of hostile behavior that was based on the respondent's interaction style during an interview. The magnitude of these age trends did not differ between men (n?=?50) and women (n?=?75). Findings illustrate the multidimensional nature of hostility. They also have practical implications for older people because hostility is associated with psychological well-being and has been shown to have consequences for health and longevity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
988.
Garcia-Molina R. Ruiz J. Chicoon R. Ortuno M. Gunn J.M.F. 《Microwave Theory and Techniques》1990,38(4):445-448
The reflection coefficient of a section of randomly rough waveguide is calculated using a coordinate transformation developed by A.K. Mallick and G.S. Sanyal (ibid., vol.26, no.4, p.243-9, 1978). A perturbed analysis which assumes that the amplitude of the roughness is small compared to the average width of the waveguide is performed. A drastic difference at long wavelengths between TEM on the one hand and TE and TM on the other has been found 相似文献
989.
BACKGROUND: Carbohydrate-Deficient Transferrin (CDT) is a new marker for excessive alcohol drinking. It appears to be useful to detect alcoholism, harmful consumption and relapse. It have been introduced in our country recently. METHOD: Recent studies about utility of CDT have been reviewed. RESULTS: Sensitivity and specificity of CDT level as a marker of alcoholism were 72-97% and 31-81% respectively. As a marker of harmful consumption its sensitivity was 15-69% and its sensitivity was higher than 82%. CDT was demonstrated to be a effective maker for evaluating alcoholic abstinence in alcoholic patients. CONCLUSIONS: CDT determinations have a high specificity for screening heavy drinking in different settings. Problems related to its sensitivity are discussed. 相似文献
990.
Failure mechanisms were studied in a unidirectional carbon/epoxy composite under uniform and linearly varying longitudinal compression. The first failure mechanism is shear yielding or shear failure in the matrix precipitated by initial fiber misalignment. It was shown how an initial fiber misalignment of 1.5° can produce the measured compressive strength of 1725 MPa (250 ksi). Matrix failure is followed by fiber buckling and fracture, resulting in the formation of a kink band. The kink band orientation is constant in the range of β = 20–30°, whereas the kink angle a varies from a small initial value to a maximum value of 2β. Kink band widths varied between 4 and 20 fiber diameters. Kink bands can occur on different planes which can rotate along the band. Kink band multiplication or broadening with increasing stress was observed at points where the maximum kink angle was reached. 相似文献