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991.
992.
Cinquemani P.L. Kuchta F.L. Hayes H.L. III Chavarria G.E. Lindler C.E. Jr. 《Power Delivery, IEEE Transactions on》2005,20(1):4-10
High-stress design 35-kV ethylene propylene rubber (EPR)-insulated cables with 1.14-mm (45-mil) wall reduction have been in service for more than ten years. In the mid 1990s, an extensive cable testing program was initiated to demonstrate that high-stress designs up to 4 kV/mm (101.6 V/mil) exhibit a significant electrical and mechanical safety margin to operate on typical utility network systems. Investigations were also undertaken to demonstrate the suitability of accessories for high-stress designs. This paper will present the results of six-year, long-term wet electrical testing conducted to demonstrate that with proper design, the aging performance of standard wall and high-stress design cables provide satisfactory results and suitable performance for the intended application. Additionally, utility field experience is presented on 35- and 15-kV cables operating at high stress. The experience for these 15-kV medium-voltage EPR cable designs employ the highest recommended stress for cables of this class, as well as taking into account the complete system performance. 相似文献
993.
Although the main function of reservoirs in agriculture is to allow the storage and temporal shifting of large volumes of waters, further benefits emerge from their application in wastewater reuse systems. In fact, as observed in several other studies carried out on such complex natural systems, the storage period, under proper conditions, can lead to a significant improvement of the water quality for irrigation thanks to concurrent physical, chemical and biological processes. In order to investigate the reservoir dynamics, an experimental research was carried out in a farm reservoir (volume of 11,000 m3, maximum depth of 6.3 m and mean depth of about 5 m), receiving treated wastewater and subject to scheduled highly variable input to volume ratios, in order to observe the broadest range of behaviour responses. Specifically, over a monitoring period lasted 4 months, the reservoir was operated as a standard batch reactor in the first and third phases and as a continuous flow reactor in the second one. Based on correlation analysis between the chemical, physical and biological water parameters and operational ones, a new operative index is proposed which integrates the morphological characteristics of the tank and the management ones, and shows a significant correlation with the qualitative characteristics of the stored water. 相似文献
994.
King Abby C.; Taylor C. Barr; Haskell William L.; DeBusk Robert F. 《Canadian Metallurgical Quarterly》1989,8(3):305
Evaluated 120 healthy, sedentary, middle-aged adults randomly assigned to either a 6-mo home-based aerobic exercise training program or to an assessment-only control condition. Adherence across the 6-mo period by the exercise group was demonstrated by self-report and heart rate microprocessor methods to exceed 75%. A 14-item Likert rating scale was used to measure a variety of psychological variables. Significant between-groups differences favoring the exercise group were found on scale items closely associated with actual physical changes that occurred with exercise (satisfaction with shape/appearance, perceived fitness). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Soybean Hulls as an Iron Source for Bread Enrichment 总被引:1,自引:0,他引:1
Soybean hulls, a concentrated source of iron, may have potential as a source of iron fortification in baked products. Retention of 59Fe in rats from white bread containing intrinsically labeled soybean hulls did not differ significantly (p<0.05) from extrinsically labeled white bread fortified with bakery grade ferrous sulfate (70.4 and 63.1%, respectively). Physical and sensory evaluations of bread containing up to 5% soybean hulls did not differ from white bread in loaf volume, cross-sectional area, tenderness or overall acceptance. These results suggest that soybean hulls are a good source of available iron and may be added to bakery products without deleterious effects in baking performance and sensory acceptability. 相似文献
996.
997.
A variational principle for magneto-elastic buckling 总被引:1,自引:0,他引:1
P. H. Van Lieshout P. M. J. Rongen A. A. F. Van De Ven 《Journal of Engineering Mathematics》1987,21(3):227-252
A variational principle that can serve as the basis for a magneto-elastic stability (or buckling) problem is constructed. For the two cases of soft ferromagnetic media and superconductors, respectively, it is shown how the variational principle directly yields an explicit expression for the buckling value. The formulation starts from a specific choice for a magneto-elastic Lagrangian L (associated with the so-called Maxwell-Minkowski model for magneto-elastic interactions). For the evaluation of the principle the first and second variations of L are calculated both inside and outside the solid magneto-elastic body. Thus, a general buckling criterion, consisting of an expression for the critical field value, together with a set of constraints for the field variables occurring in the right-hand side of this expression, is constructed. Finally, more detailed formulations are given for, successively, soft ferromagnetic bodies and superconductors. Applications to specific structures, yielding explicit numerical values for the magneto-elastic buckling fields, will be given in a forthcoming paper. 相似文献
998.
Rate of passage from the rumen was estimated from samples from the rumen, duodenum, ileum, and rectum after four crossbred heifers were dosed with cobalt ethylenediaminetetraacetic acid and ytterbium-labeled alfalfa or corn grain as digesta markers. Diets consisted of chopped alfalfa hay or an 80% concentrate mixture fed twice daily at 2.0% of body weight (dry matter per day) in two trials. Rates of particulate passage were calculated by two mathematical models, and influence of site of sampling on rate of ruminal passage was appraised. Rate of fluid passage calculated from ruminal samples was more rapid than rates from samples at the duodenum, ileum, and rectum for both the alfalfa diet (10.6 versus 6.3, 5.6, and 5.6% X h-1) and the 80% concentrate diet (10.3 versus 6.8, 7.2, and 6.1% X h-1). With the alfalfa diet, rates of fluid passage estimated from ruminal and rectal samples were correlated .98 despite the marked disparity of means. Rates of passage of particulates estimated from samples from the duodenum, ileum, and rectum were not correlated. Estimates of rate of digesta passage from the rumen differed with postruminal site of sampling. 相似文献
999.
F. R. DEL VALLE H. VILLANUEVA J. REYES-GOVEA M. ESCOBEDO M. J. MUNOZ J. PONCE M. VEGA M. HERNANDEZ G. VELAZQUEZ 《Journal of food science》1985,50(2):551-552
A nitrogen balance study, comparing a low-cost soy-oats infant formula with and without supplemental methionine, was carried out with infants of ages 3 - 26 months at a single equivalent level of nitrogen intake (approximately 850 mg/kg/day). Nitrogen retention was found to be unaffected by methionine supplementation. Com- parison of data obtained in this study with previous research re- vealed that a critical value for intake of total L-sulfur amino acids apparently exists in infants 3 - 26 months of age, below which methionine supplementation will increase nitrogen retention, but above which it will not. This value appears to coincide with that of 49 mg/kg/day recommended for infants by the FNB. 相似文献
1000.
Prevention of the green-grey discoloration of liquid whole eggs cooked at high temperatures was studied. Disodium ethylenediaminetetraacetic acid (NaZEDTA) was used to prevent the discoloration in whole egg adjusted to pH 8.5. Liquid egg samples in flexible packages were subjected to retort conditions (121°C, for 20 min) and evaluated for off-color development. Discoloration was more severe at higher temperatures and longer cooking times; however, the use of 0.015% NazEDTA was effective in preventing green-grey color development. 相似文献