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1.
We investigated the effect of aligning crystal orientation in the microstructures containing sub micro-sized grains on the thermoelectric properties for polycrystalline Bi-Te materials.Bi-Te powder,prepared through the conventional pulverization process,was sufficiently dispersed in an appropriate solvent,and then was formed into c-axis aligned green bodies under a designated high magnetic field.The green bodies were sintered with spark-plasma-sintering machine.The degree of crystal alignment of sintered bodies was examined with the electron-back-scatter-diffraction SEM and the X-ray diffraction patterns.It was observed that for both p and n type thermoelectric Bi-Te materials,aligning crystal orientation properly made electrical resistivity decreased with keeping Seebeck coefficient and thermal conductivity remained unchanged.As a typical result,the aligned Bi-Te material with the magnetic field of 10 tesla showed 30%enhancement of the thermoelectric performance. 相似文献
2.
Sweet potato and corn starches were gelatinized and liquefied to dextrose equivalent (DE) 10 in a steam-jacketed kettle or in a twin-screw extrusion cooker in a single step process with a heat stable ex-amylase. The time required to gelatinize and liquefy 20% starch slurries in a kettle at 95°C was 45 to 50 sec. Starch powder (10 kg/hr) and water (2-6 kg/hr) were fed to an extrusion cooker to adjust the moisture contents of the starch from 20 to 55% (wet basis) and gelatinized and liquefied to DE 10 at a barrel temperature of 120°C or above with 2 to 3% (w/w) a-amylase added. The optimum conditions for the operation were to feed starch with water to maintain 50% moisture and 2% heat stable a-amylase at a barrel temperature of 120°C. 相似文献
3.
An all-fiber wavelength selective Q-switching modulator based on fiber grating loop mirror is proposed.A newly configured Q-switched erbium doped fiber laser using this all-fiber modulator is numerically analyzed taking into account the effects of the spontaneous emission 相似文献
4.
Extraction of hydrated and freeze-dried bakers’yeast yielded ~ 50 μg erythroascorbic acid (EAA) and 5 μg ascorbic acid (AA)/g dry yeast as determined by HPLC with electrochemical detection. D-EAA (82 ppm based on flour) slightly increased the flow of dough as rest time increased. Gluten isolated from a flour-water dough containing 82 ppm D-EAA or 100 ppm Lcysteine stretched at a faster rate than control gluten. EAA like AA did not change dough development time. Unlike AA, EAA showed neither oxidizing effect on dough and gluten nor improving effects on bread. 相似文献
5.
YANBIN LI MICHAEL F. SLAVIK CARL L. GRIFFIS JEONG-WEON KIM 《Journal of Food Safety》1993,13(4):241-252
Electrical stimulation was evaluated as a method to kill Salmonella typhimurium in various salt solutions at different concentration . Salmonella typhimurium at 2 × 105 CFU/ml was treated at 22–24C for 60 min in each salt solution using electricity at 10 mA/cm2 current, 1 kHz frequency, and 50% duty cycle. Samples taken at various times were serially diluted, plated on tryptic soy agar and xylose lysine desoxycholate agar, and incubated at 37C for 18–24 h. To detect injured cells, samples were also pre-enriched in buffered peptone water at 37C for 4–5h before being plated. Results indicated all salmonellae were electrically killed at 5 min in NaCl, at 30 min in NaNO3 , and at 45 min in NaC2 H3 O2 at 0.15 and 0.015 M concentrations. Salmonellae were also killed at 45 min in Na3 PO4 and at 60 min in Na2 CO3 at 0.0015 M concentration by electricity in combination with high pH . 相似文献
6.
High-Protein Texturized Products of Defatted Soy Flour, Corn Starch and Beef: Shelf-Life, Physical and Sensory Properties 总被引:3,自引:0,他引:3
Selected mixes consisting of Bf [high-beef (29%) low-fat (2.96%)], bf [low-beef (20%) low-fat] and BF [high-beef high-fat (5%)] which incorporated raw beef, defatted soy flour, and corn starch were extruded in a single-screw extruder. The products had no flavor additives and trained sensory panelists detected hay-like, beany or grainy flavors. Bf extrudate was more expanded than BF extrudate and rated least hard by the sensory panel, whereas bf extrudate was least susceptible to lipid oxidation. Bf and bf extrudates showed microstruc-tures with large air cells. All three showed advantages of beef and soy flour in amino acid and fatty acid compositions, respectively, and were microbiologically safe during prolonged storage at 37°C. 相似文献
7.
The changes in the size and shape of soybean protein bodies in different solvent systems were observed, and their influence on hydrodynamic properties in solutions was investigated by capillary viscometer. The intrinsic viscosity of the isolated protein bodies varied with the type of dispersion media; 0.036 cm3/g in CCI4-benzene solution, 0.355 cm3/g in 50% glycerol-water mixture, 0.574 cm3/g in water at pH 7, and 1.18 cm3/g in the aqueous solution at pH 12. The hydration of the protein bodies in different dispersion media was estimated by Oncley's method and Mooney's method. The estimated degree of hydration agreed well with the swelling of the protein bodies as observed by microscope. 相似文献
8.
KONG-HWAN KIM HENRY G. SCHWARTZBERG JOHN R. ROSENAU 《Journal of food process engineering》1983,7(1):37-62
Concentrated CaCl2 and LiCl brines were used to evaporatively concentrate liquid foods. The concentration was carried out in double falling film evaporators in which brine flowed down the outside of the tubes and liquid food flowed down the inside. The vapor spaces between the brine and the food were connected and vapor from the food was absorbed in the brine. The heat generated by vapor absorption in the brine provided the heat needed to sustain evaporation, and was transferred to the food because of the boiling point elevation of the brine. Evaporation rates approaching those obtained in commercial evaporators were obtained for skim milk, sugar solutions and orange juice. The evaporation rates were affected by flow rates, temperature, concentration and tube material. 相似文献
9.
To solve information asymmetry problem on online auction, this study suggests and validates a forecasting model of winning bid prices. Especially, it explores the usability of data mining approaches, such as neural network and Bayesian network in building a forecasting model. This research empirically shows that, in forecasting winning bid prices on online auction, data mining techniques have showed better performance than traditional statistical analysis, such as logistic regression and multivariate regression. 相似文献
10.
USE OF OZONE TO INACTIVATE MICROORGANISMS ON LETTUCE 总被引:6,自引:0,他引:6
When ozone (1.3 mM) was bubbled for 3 min in a mixture of shredded lettuce and water, counts ofmesophilic andpsychrotrophic bacteria decreased 1.4 and 1.8 log10 cfu/g, respectively. Counts of these microorganisms on lettuce, from a different batch, decreased 3.9 and 4.6 log, respectively, during 5 min of ozone treatment. Shredded lettuce was treated with gaseous ozone, or mixed with aqueous solution of ozone (1:20 w/w) with or without bubbles. For effective delivery of ozone, stirring (low and high speed), sonication or stomaching was applied during the ozonation. Washing the lettuce with water only decreased total count on shredded lettuce by 0.74–1.0 log cfu/g. When lettuce in a treatment chamber was flushed with gaseous ozone, the total count decreased 0.85 log cfu/g, but when vacuum was applied before the ozone flush, the total count decreased 0.96 log cfu/g. Bubbling ozone in water-lettuce mixture while sonicating, high-speed stirring, or before stomaching inactivated 1.4, 1.9 and 1.9 log cfu/g, respectively. In conclusion, bubbling gaseous ozone in water is the most effective ozonation method. Efficient ozone delivery to microorganisms on lettuce requires a combination of ozone bubbling and high-speed stir. 相似文献