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21.
Kwang Soo Lee In Soo Park & Dong Sun Lee 《International Journal of Food Science & Technology》1996,31(1):7-13
The aim of this study was to design a modified atmosphere package for a mixed vegetable salad consisting of 75 g of cut carrot, 55 g of cut cucumber, 20 g of sliced garlic and 50 g of whole green pepper. Respiration data of all the components were combined with film permeability data to predict package atmospheres and design optimal packages for experimental testing for improved shelf-life of the produce. The optimal package avoided minimum O2 and maximum CO2 tolerance limits, and chilling injury temperatures for any component. A pouch form package made of 27 mm low density polyethylene developed a modified atmosphere of 2.0–2.1% O2 and 5.5–5.7% CO2 , which was beneficial for all components and provided better quality retention than other test packages. 相似文献
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W D Tiner 《International Journal of Project Management》1985,3(1):13-18
In order to control a project, construction management requires project information. This is obtained through accounting, estimating, cost management and scheduling functions which produce project reports. These reports are best obtained by subdividing the project into small parts. The ways in which each of these functions subdivides a project in order to produce its reports is discussed, together with a means of interrelating this information with a technique known as the work breakdown structure. 相似文献
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Vibro-fluidized beds are widely used in drying sticky powders and agglomerated materials as milk powder. Using a vibro-fluidized laboratory scale dryer, this work is aiming at analyzing preliminarily the effect of its operational variables on the drying kinetics and characteristics of whole milk powder. The full-factorial design technique with three replications at the central point has been employed to generate data and correlations to quantify the effect of inlet air temperature, air flow rate, and vibration bed amplitude on the drying curves and the milk powder properties related to its faster reconstitution in water (as tapped density, Hausner cohesion ratio, agglomerate size distribution, and internal pore concentration). Results obtained are analyzed and discussed to identify the adequate operation condition for final drying whole milk powder in vibro-fluidized beds, assuring a high product quality. 相似文献
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Jennifer G. Winter M. Catherine Eimers Peter J. Dillon Lem D. Scott Wolfgang A. Scheider Campbell C. Willox 《Journal of Great Lakes research》2007,33(2):381-396
Total phosphorus (TP) inputs to Lake Simcoe have led to hypolimnetic dissolved oxygen (DO) depletion and loss of cold water fish habitat. Since 1990, efforts have been made to reduce the total TP input to the lake below a defined target of 75 t/year, which was predicted to lead to reductions in spring TP concentration and improvements in end-of-summer hypolimnetic DO concentrations. The total TP load to the lake during the most recent period of record (1998/99-2003/04) ranged from 53 to 76 t/yr and averaged 67 t/yr, compared to an average of 114 t/yr estimated between 1990/91 and 1997/98 (range 85-157 t/yr). Reductions in TP loads from the catchment via tributary discharge (∼26 t) accounted for the majority of the decrease in total load between the two time periods. Total P concentrations decreased significantly in four out of six long-term monitored tributaries; however, concentrations in all six tributaries remain above the level recommended to avoid nuisance plant growth (30 μg/L). Although TP loads to the lake are currently below the target 75 t/yr, excessive growths of filamentous algae and macrophytes continue to be a problem in the nearshore zone. End-of-summer minimum hypolimnetic DO concentrations (average 4.3 mg/L, 1998/99-2003/04) remain substantially below the level (7 mg/L) that is considered protective of lake trout. Efforts to reduce TP loads to the lake therefore need to continue. 相似文献
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论社区服务产业化 总被引:2,自引:0,他引:2
刘波 《重庆理工大学学报(自然科学版)》2003,17(1):127-131
社区经济作为一种优化的资源配置方式,利用社区服务为载体,将社区内互不相联的各种经济成份变为利益共同体,建立一种新的经济生产方式,从而带动社区乃至更广区域的经济发展。 相似文献
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