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Choe JH  Jang A  Lee ES  Choi JH  Choi YS  Han DJ  Kim HY  Lee MA  Shim SY  Kim CJ 《Meat science》2011,87(1):12-18
This study aimed to evaluate the oxidative and color stability of cooked ground pork containing lotus leaf powder at 0.1 (LP1) and 0.5% (LP2) as well as barley leaf powder at 0.1 (BP1) and 0.5% (BP2) during refrigerated storage for 10 days. The oxidative stability of these powders was compared with butylhydroxytoluene (BHT). LP1 had higher a* and lower b* values than the control (-) over 4 days (p<0.05). The pH values of the ground pork samples made with addition of LP and BHT decreased until day 4 and then increased. Thiobarbituric acid-reactive substance (TBARS) values were lowest in LP2 on day 10 (p<0.05). The ground pork samples containing LP and BP had lower peroxide values (POVs) and conjugated dienes (CD) compared to the control (-).These results indicate that LP or BP can be incorporated into ground pork to effectively retard oxidation after cooking.  相似文献   
43.
Response surface methodology was used for optimizing the ratio of vegetable oil and carbon black and occluded volume fraction of rubber in the compound. Central composite design for two variables was chosen as the experimental design. The data obtained from measurement of properties was fitted as a two variable second-order equation, and were plotted as contours using software developed from MATLAB v.5.1. From contours it is observed that at the ratio of 0.06 of vegetable oil and carbon black, there is maximum coupling, and a further increment in vegetable oil and carbon black ratio shows less coupling and more plasticizing effect. The ultimate failure properties like tensile and tear strength and elongation decreases with an increase in occluded volume fraction, reaches a minima at the central region, followed by an increase, whereas 300% modulus and hardness decreases throughout.© 2001 John Wiley & Sons, Inc, J Appl Polym Sci 82: 997-1005, 2001  相似文献   
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Stability of meoru (Vitis coignetiea) anthocyanins during heating under singlet oxygen to simulate low sugar meoru jam-making was studied. Samples consisted of meoru juice, sugars (sucrose, glucose, or fructose), and pectin were placed at 10 or 90°C under singlet oxygen which was produced with riboflavin under 5,500 lx. Anthocyanins present in samples were malvidin-3,5-diglucoside, delphinidin-3-glucoside, cyanidin-3,5-diglucoside, malvidin-3-glucoside, and cyanidin-3-glucoside in a decreasing order. Meoru anthocyanins were degraded under singlet oxygen and heating accelerated the degradation. Degradation was faster in monoglucoside anthocyanins than diglucoside anthocyanins, and in samples added with sucrose or fructose than in samples with glucose. Sucrose in samples was hydrolyzed to glucose and fructose possibly by acid present in meoru, at higher rate at 90°C than at 10°C. Simple sugars added or produced by hydrolysis of sucrose were stable during heating or at 10°C under singlet oxygen, possibly due to quenching activity of meoru anthocyanins on singlet oxygen.  相似文献   
45.
Failure analysis of a boiler tube in USC coal power plant   总被引:2,自引:0,他引:2  
This paper presents failure analysis of final superheater tube in ultra-supercritical (USC) coal power plant. Visual inspection was performed to find out the characteristics of fracture of the as-received material. And the micro-structural changes such as grain growth and carbide coarsening was examined by scanning electron microscope. Detailed microscopic studies were made to find out the behavior of the scale exfoliation on the waterside of tubes. From those investigations, the creep rupture may be caused by the softened structure induced by carbide coarsening and accelerated by the metal temperature increase by the impediment of heat transfer due to voids.  相似文献   
46.
The aim of this study is to derive parameters from spectral variations associated with heavy metals in soil and to explore the possibility of extending the use of these parameters to hyperspectral images and to map the distribution of areas affected by heavy metals on HyMAP data. Variations in the spectral absorption features of lattice OH and oxygen on the mineral surface due to the combination of different heavy metals were linked to actual concentrations of heavy metals. The ratio of 610 to 500 nm (R610,500 nm) in the visible and near-infrared (VNIR) range, absorption area at 2200 nm (Area2200 nm), and asymmetry of the absorption feature at 2200 nm (Asym2200 nm) showed significant correlations with concentrations of Pb, Zn, and As, respectively. The resulting spectral gradient maps showed similar spatial patterns to geochemical gradient maps. The ground-derived spectral parameters showed a reliable quantitative relationship with heavy metal levels based on multiple linear regression. To examine the feasibility to applying these parameters to a HyMAP image, image-derived spectral parameters were compared with ground-derived parameters in terms of R2, one-way ANOVA, and spatial patterns in the gradient map. The R1344,778 nm and Area2200 nm parameters showed a weak relationship between the two datasets (R2 > 0.5), and populations of spectral parameter values, Depth500 nm, R1344,778 nm, and Area2200 nm derived from the image pixels were comparable with those of ground-derived spectral parameters along a section of the stream channel. The pixels classified in the rule image of Depth500 nm, R1344,778 nm, and Area2200 nm derived from a HyMAP image showed similar spatial patterns to the gradient maps of ground-derived spectral parameters. The results indicate the potential applicability of the parameters derived from spectral absorption features in screening and mapping the distribution of heavy metals. Correcting for differences in spectral and spatial resolution between ground and image spectra should be considered for quantitative mapping and the retrieval of heavy metal concentrations from HyMAP images.  相似文献   
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The Bladder Neck Support Prosthesis (BNSP) was used in 21 women with combined genuine stress incontinence (GSI) and detrusor instability (DI). Outcomes included frequency volume charts, pad tests, voiding cystometry and quality of life scores, up to the sixth month. Of the 21 recruits, 5 never wore the BNSP home, leaving 16 participants. A further 2 did not reach week 4 because of poor efficacy or inability to fit the device. In the 14 who reached week 4, the median number of leaks/day declined from 4.3 to 1.0 (p = 0.002). Median pad test loss fell from 53 to 7 mL (p = 0.012). Cystometry showed an increase in maximum bladder capacity (p < 0.05) and a modest reduction in severity of detrusor instability, with no evidence of outflow obstruction. Three further women discontinued because of poor efficacy (2) or a poorly fitting device (1), leaving 11 of 16 participants (69%) at week 8, when median pad test loss fell to 2 mL. The BNSP is a useful option in patients with the unfortunate combination of an unstable bladder and an incompetent urethra, but requires careful fitting and attention to detail.  相似文献   
49.
Piles are used for platform foundations and other offshore structures. Pile driving performance is predicted and analyzed using the wave equation analysis method. In general, the hammering point can be any part of the pile and the same analyses used for hammering at the top of the pile (top hammering) can be used for pile driving by hammering at the bottom of the pile (bottom hammering). Based on the numerical analyses in this research including residual stresses in the pile, there is little difference between the predictions of pile penetration per hammer blow by single- or multiple-blow analyses when soil resistance is low, such as 10 blows/m. The same is true for top hammering and bottom hammering when soil resistance is low. However, when soil resistance is high compared to that of the pile-hammer system, single-blow analysis predicts early refusal for top hammering and unrealistically high pile penetration for bottom hammering. Therefore, multiple-blow analysis, which considers residual stresses, should be used for better understanding of realistic pile driving performance and predictions. Additionally, this study shows that gravity is another controlling factor for pile driving in low-resistance soil.  相似文献   
50.
Carbon dioxide was absorbed into the phenyl glycidyl ether (PGE) solution within a range of 0–2.0 kmol/m3 in a stirred batch tank with a planar gas-liquid interface at 333–363 K and 101.3 kPa. Trihexylamine-immobilized on chloropropyl-functionalized MCM-41 (THA-CP-MS41) was used as a mesoporous catalyst, dispersed in organic liquid for the reaction between carbon dioxide and PGE. The measured absorption rates were analyzed to obtain the reaction kinetics of the consecutive chemical reactions which consisted of two steps using the mass transfer mechanism based on film theory. The overall reaction kinetics, analyzed with the pseudo-first-order reaction constant in the consecutive reaction model, was equivalent to the consecutive reaction kinetics. Effects of polar solvent, such as N, N-dimethylacetamide, N-methyl-2-pyrrolidinone, and dimethyl sulfoxide, on the reaction rate constants were observed using the solubility parameter of the solvent.  相似文献   
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