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排序方式: 共有1979条查询结果,搜索用时 15 毫秒
101.
Elias C. Aifantis 《International Journal of Engineering Science》1980,18(6):857-867
The problem of flow in media with double porosity (e.g. fissured rocks) is considered by utilizing the author's concept of “multiporosity” and employing the apparatus of continuum theory of mixtures. Relevant results obtained by Barenblatt et al. within the Russian literature are shown to be contained in the present theory. 相似文献
102.
103.
LR Barot JL Rombeau TP Stein R Chernoff RG Settle JL Mullen 《Canadian Metallurgical Quarterly》1982,6(1):34-38
To establish an animal model for the controlled study of enteral nutrition by tube, five adult chair-adapted primates (Macaca fasicularis) had gastrostomy and jejunostomy tubes placed for the delivery of a modified protein isolate diet. Following 7 days of postoperative depletion with a hypocaloric infusion of dextrose (20 kcal, 0 g N/kg/day), the animals were repleted for 10 days with tube feedings (124 kcal, 0.73 g N/kg/day). There was no operative mortality or morbidity and each animal demonstrated conversion to anabolism by significant weight gain, positive nitrogen balance, and net protein synthesis as determined by [15N]glycine protein turnover rates. Significant correlation was found between caloric intake and nitrogen balance at the level of nitrogen provided in this diet (r = 0.88, p less than 0.05). This model was found to be well suited for the surgical and nutritional techniques required for the long-term study of enteral nutrition by tube. 相似文献
104.
E. Elias 《Nuclear Engineering and Design》1981,64(2):249-257
A theoretical model is developed which allows a consistent treatment of the wall heat flux in an inverted-annular film boiling regime. The model is based on an analytical solution of the energy conservation equations in the vapor and liquid regions downstream of the quench front. A constant vapor film thickness is assumed, which depends on the fluid equilibrium quality at the quench front. Good agreement is obtained in comparing the model with quasi-steady state experimental results. 相似文献
105.
RT Geer LR Soma C Barnes JL Leatherman BE Marshall 《Canadian Metallurgical Quarterly》1976,16(10):788-791
Aspiration of hydrochloric acid in rabbits resulted in an increased P(A-a)O2 together with increases in both lung water volume and lung extravascular albumin. This finding suggests lung damage following acid aspiration is related to changes in capillary permeability, with pulmonary edema resulting from the movement of albumin and water into the interstitial space. Therapy with albumin and furosemide together reduced the lung water and albumin accumulation and decreased P(A-a)O2. Treatment with albumin or furosemide alone was ineffective. Caution should be exercised in administering albumin alone for therapy of pulmonary edema when plasma protein is not clearly decreased, or when increased pulmonary capillary permeability is suspected. 相似文献
106.
107.
Thirteen autistic children were compared to 13 normal children matched to them in mental age, on performance of a visual discrimination task. Form, color, and size were relevant and redundant cues. The groups did not differ significantly in mean trials to reach criterion or in breadth of learning, and both groups increased their breadth of learning after 50 trials of overtraining. Form was preferred to color and size by both autistic and normal children. Within each group, rank on mental age was highly correlated with rank in breadth of learning. Verbal and nonverbal autistic children did not differ in breadth of learning or in dimensional preference. Even nonverbal autistics equaled the performance of their normal controls. Our results suggest that overselective attention is better understood as part of a general developmental lag in cognition in autistic children than as a specific deficit underlying psychotic behavior. 相似文献
108.
SEM and X-ray microprobe analysis were combined with clean lab technology atomic absorption spectroscopy to observe the deposition of aerosols on undisturbed pine needle surfaces, to obtain physical and chemical information from the observed particles and to chemically remove these particles for analysis. Comparisons were made among sites with traffic densities of 100, 1000, 10000 cars per day. Correlations were made with periods of heavy rainfall. The results show that the particle size distribution, shape and surface chemistry are possibly characteristic of automotive exhausts, that both the chemical washing procedure and rainfall efficiently remove most particles from the surface, including those bearing lead, and that the rate of deposition is constant between rainfalls and partly a function of traffic density. Deposition rates of 0.3 ng Pb cm?2 day?1 were observed at 100 cars per day, 2–3 ng Pb cm?2 day?1 for 1000 and 10000 cars per day. 相似文献
109.
110.