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51.
The scanning electron microscope has proven itself efficient for determining dopant concentrations in semiconductors. Contrast between differently doped areas is observable in the secondary electron emission. Multiple studies have revealed quantitative relations between the image contrast and dopant concentration. However, intimate examination shows a low reproducibility of the contrast level for a particular local difference between the doping rates. Data about dynamic behaviour of the dopant contrast and its dependence on the status of the sample surface are presented.  相似文献   
52.
The effect of visibly inferior flaxseed ( Linum usitatissimum L.) on the lipid quality of milled flaxseed was investigated. Flaxseed was aspirated and separated into low-, medium- and high-density fractions. All density fractions contained ≤ 0.1% broken seed, ≤ 0.4% contrasting seed and ≤ 0.25% extraneous material. The low-density fraction contained the most immature (2.8%) and off-colored seed (4.1%). Immature seed had a lipid content of 40.8%, a peroxide value (PV) of 2.69 meq/kg and a free fatty acid (FFA) content of 1.06%. The off-colored seed had a lipid content of 38.1%, a PV of 5.79 meq/kg, and a FFA content of 1.89%. Hand-cleaned seed (averaged across fraction density) had a lipid content of 41.4%, a PV of 0.41 meq/kg and FFA content of 0.37%. The removal of seed defects improved flaxseed quality and improved lipid quality in the low-density fraction.

PRACTICAL APPLICATIONS


Lipid oxidation is a major concern when using milled flaxseed as a food ingredient. These results indicate the importance of removing off-colored and immature flaxseed. Seed lots that contain immature and off-colored seed likely will have poor lipid quality and, when milled, be more susceptible to lipid oxidation during storage than will seed lots free of immature and off-colored seed.  相似文献   
53.
ENZYMATIC HYDROLYSIS OF SOYBEAN FOR SOLVENT AND MECHANICAL OIL EXTRACTION   总被引:1,自引:0,他引:1  
Due to inefficient extractability of its low oil content, soybeans are often bypassed in village‐scale processing. Soygrits, flakes, and expanded collets were hydrolyzed by proteases, cellulases, and pectinases before oil extraction by solvent and static mechanical pressure. Driselase with multi‐enzyme activity and two proteases improved solvent extraction rates but only Driselase enhanced mechanical pressing. Up to 58% of seed oil was pressed from enzyme‐hydrolyzed flakes but 88% was pressed from Driselase‐treated collets. Either pretreatment is a feasible adjunct to mechanical pressing in small batch operations.  相似文献   
54.
In a recent study, the capillarization of normal prostatic tissue and prostatic carcinoma tissue was characterized by means of explorative methods of spatial statistics. In the present paper, an attempt was made to go beyond the explorative approach and to characterize the observed point patterns of the capillary profiles on sections by means of a parametric model. For this purpose, the flexible class of Gibbs processes was considered. Specifically, stationary Strauss hard-core processes were fitted to the observed point patterns. The goodness of fit achieved by the model was checked by simulations with the Markov chain Monte Carlo method using the Metropolis–Hastings algorithm. Model fitting and simulations were performed with the help of the spatstat package under R. The observed point patterns were in some cases compatible with realizations of stationary Strauss hard-core processes for all ranges of spatial interaction. However, deviations from the model were found for one or more domains of ranges in other cases. In the tumour tissue, a highly significant decrease of the interaction parameter of the Strauss hard-core process could be found as compared to the normal prostatic tissue. This finding is discussed in terms of a loss of the normal lobular architecture of the glands in the tumour tissue.  相似文献   
55.
把窑炉中的玻璃液放干,即是在冷修或从窑炉中回收玻璃。经常用此种技术降低炉内玻璃的液面,或改变玻璃品种/颜色时或在新生产技术的试验中,用同样的技术清洗窑炉。  相似文献   
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57.
Three selected carbohydrate-based fat replacers which were derived from pectin, gums, and oat bran (Slendid, Kel-Lite BK and TrimChoice-5, respectively) were used at a fixed rate in biscuits while shortening was reduced at 33, 66 and 100%. The principal effects of each fat substitute on biscuit quality varied with the fat substitute type and level of fat. Generally, fat substitute usage produced a significant (p < 0.05) increase in moisture content, as well as a light crust color. Variations in volume and crumb firmness were associated with the type of fat substitute and level of fat. Sensory data were found to be in agreement with the analytical data for moistness, crust color and crumb firmness. Crumb size decreased and bitterness was detected in biscuits as fat levels decreased regardless of the type of fat substitute.  相似文献   
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59.
FROM EYSENCK'S PERSONALITY THEORY AND RECENT NOTIONS OF STIMULUS-SEEKING BEHAVIOR, IT WAS PREDICTED THAT EXTRAVERSION WOULD CORRELATE WITH STIMULUS SEEKING AS MEASURED BY THE SENSATION SEEKING SCALE OF ZUCKERMAN, KOLIN, PRICE, AND ZOOB. THE CORRELATION FOUND WAS .47, P  相似文献   
60.
Because of increased interest in color uniformity among iron-sulfur amber bottle glasses, a study was undertaken of their color, their spectral transmittance, and the relationship of these properties. It was found that the psychophysical attributes of color (C.I.E. system) as computed from complete light-transmittance spectra can actually be estimated for iron-sulfur amber glasses with good accuracy from transmittance at only two suitable wave lengths, 550 and 650 mp. Transmittance at 550 mμ is closely correlated with brightness (C.I.E.) and thus is sufficient to characterize color intensity, which is the most important variable of color quality among commercial amber glasses. There is also fair correlation between transmittance at 550 mμ and transmittance in the ultraviolet. The latter is important in the avoidance of photochemical action on bottled products. Incidental to this work, the transmittances of a large number of glasses were compared with their iron and sulfur contents. Broadly speaking, it was found that transmittance at 550 mp decreases with increasing ferrous iron or with increasing sulfide content. However, this transmittance is affected substantially by other factors, such as gross composition, minor constituents like fluorine, and thermal history, of which no account was taken in the present work. Transmittance at 1050 mp can be correlated closely with ferrous iron content (as determined by chemical analysis) and absorbancy per unit concentration of ferrous iron in carbon-sulfur ambers is about the same as in green glasses containing no sulfur.  相似文献   
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