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991.
对水冷分离式制冷系统进行了初步分析,并结合工程实例与水冷式冷水主机制冷系统进行比较,尝试找出其在工程中的适用范围。 相似文献
992.
993.
994.
Environmental Scanning Electron Microscopy Evaluation of Tortilla Chip Microstructure During Deep-Fat Frying 总被引:2,自引:0,他引:2
C. McDONOUGH M.H. GOMEZ J. K. LEE RD. WANISKA L.W. ROONEY 《Journal of food science》1993,58(1):199-203
When the baked chip was immersed in the fryer, oil immediately coated and clung to the surface and began to move into the chip. As heat built up within the chip, the moisture turned to steam and exited the chip leaving behind a sponge-like network of tunnels which became filled with oil. The transformations occurred within 20 sec. As frying time increased, (1) starch granules with strong birefringence remained on the surface of the chip, (2) starch granules lost birefringence within the chip, and (3) the interior of the chip became smooth and plastic in appearance as protein, starch and lipids interacted to form a continuous phase that hardened upon dehydration. 相似文献
995.
Y. D. LEE R. C. McCLUNG G. G. CHELL 《Fatigue & Fracture of Engineering Materials & Structures》2008,31(11):1004-1016
This paper summarizes the development of an efficient stress intensity factor (SIF) solution scheme applicable to a corner crack (CC) in a rectangular section subjected to arbitrary stressing on the crack plane. A general bivariant weight function (WF) formulation developed previously for a CC in a plate was extended to address a CC at a hole. Two supplemental algorithms were developed to achieve a substantial reduction in the computational time necessary for practical application. The new SIF solution scheme was validated by comparison with more than 180 three‐dimensional (3D) boundary element (BE) solutions. 相似文献
996.
997.
This study was undertaken to determine the effect of preparation and service, particularly reheating methods, on the thiamin content of freshly prepared and leftover Italian spaghetti in a university cafeteria foodservice. The processes studied include hot steam-table holding, 4 wk of frozen storage, and reheating by microwave and conventional ovens. No significant losses occurred in thiamin content of the Italian spaghetti after hot-holding, freezing, microwave or conventional reheating. Thus it can be concluded that the thiamin losses of Italian spaghetti prepared and served in cafeteria-style foodservices are not significant. 相似文献
998.
Carotenoid loss in dried red pepper products 总被引:1,自引:0,他引:1
DONG SUN LEE SYUNG K. CHUNG KIT L. YAM 《International Journal of Food Science & Technology》1992,27(2):179-185
The carotenoid loss in dried red peppers, whole, and as coarse and fine powders, with and without seeds, was studied under various water activities, storage temperatures, and packaging atmospheres. Carotenoid loss of red pepper is affected by water activity, package atmosphere, storage temperature, and treatment of pepper. Nitrogen flushing or high water activity can increase carotenoid retention. To maintain good colour quality, both high carotenoid retention and low browning, red peppers should be stored in the form of coarse powder with seeds, at water activity below 0.3, and in a nitrogen atmosphere. 相似文献
999.
PbO thin films were deposited on a silicon substrate by plasma-enhanced chemical vapour deposition (PECVD) using Pb(C2H5)4 and oxygen at 250°C. The interdiffusion reaction phenomena between the PbO thin film and the silicon substrate during heat
treatments were investigated in a horizontal furnace in the temperature range between 350 and 650°C under a nitrogen ambient
for 1 h. The PECVD PbO film deposited on the silicon substrate at 250°C, was amorphous and contained carbon-related contaminants
which could almost be removed by heat treatment at 350°C. The PbO on the silicon substrate initially participated in the interdiffusion
reaction in the temperature range between 400 and 450°C. This produced a silicate layer containing lead components. The lead
content in the film varied with the depth of film and heat-treatment temperature. Metallic lead was observed as a cluster
in the specimen heated at 550°C. This cluster was produced by the agglomeration of metallic lead originating from PbO decomposition.
The oxygen source for silicate formation was not ambient oxygen coming from the decomposition of Pb–O bonding. The metallic
lead clusters dissolved as weakly bound metallic lead or as an unbound nanosized metal particle in the silicate layer at 650°C.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
1000.
JIB ZHANG TUNG CHING LEE CHI-TANG HO 《Journal of Food Processing and Preservation》1993,17(4):259-268
Nonenzymatic deamidation of glutamine and asparagine residues of soy protein in aqueous solutions of varying pH (3.0, 5.0, 7.0, 9.0 and 11.0) at different temperatures (100C, 115C and 130C) was monitored over a period of time. the deamidation of soy protein followed first-order kinetics. the activation energies (Ea) of soy protein deamidation at different pHs ranged from 14 to 27 Kcal/mol. the activation energies were highly pH-dependent and decreased very sharply as the pH went up from pH 5 to pH 11. 相似文献