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81.
EXPERIMENTAL INVESTIGATIONS ON DIFFUSION CHARACTERISTICS OF HIGH CONCENTRATION JET FLOW IN NEAR REGION 总被引:3,自引:2,他引:1
Zhang Yan Wang Dao-zeng Fan Jing-yu Shanghai University Shanghai Institute of Applied Mathematics Mechanics Shanghai China 《水动力学研究与进展(B辑)》2001,(1)
1 . INTRODUCTIONTheresearchofjetisanimportantfieldinfluidmechanics.Italsohasmanyapplicationsinengineering ,forexample ,thedischargeofpollutantandcoolingwaterinindustries .Whentheinitialdensityofthejetisdifferentfromthatoftheambientwaterbody ,thejetwillbeaf… 相似文献
82.
水性聚氨酯电导率与聚沉值的研究 总被引:4,自引:0,他引:4
研究了软(硬)段含羧基的水性阴离子纳米聚氨酯体系的n(NCO)/n(OH)比值,COOH的质量分类,反离子各类,合成方法与电导率关系及产生的原因;探讨了该体系的n(NCO)/n(OH)值,COOH的质量分数,合成方法与临界聚沉值(Cc.c)的关系和规律。并分析,比较了软(硬)段含羧基的水性阴离子聚氨酯体系电导率与Cc.c二者关系,得出了随COOH的质量分数升高,二者变化相同,随n(NCO)/n(OH)比值升高,二者变化相反的结论。 相似文献
83.
84.
介绍65t/h煤粉炉的基本概况和存在的问题,详细阐述了采用水平浓缩煤粉燃烧技术对原燃烧器的改造过程,对改造前后运行参数及经济效益进行了对比。 相似文献
85.
Emaeyak N Ukpong C S Odoemena G Ekpo 《Journal of the science of food and agriculture》1994,64(4):449-453
Aspergillus niger (strain UUF9202) significantly reduced the dormancy period and boosted aggregate germination percentage (AGP) in seeds of Tetrapleura tetraptera. A net reduction in mean germination time (MGT) to 12 days and an increase from 0 to 42% AGP were obtained in 32 days. The optimal spore inoculum of the fungus was 8.5 × 10≥10 ml?1 per 100 seeds in 96 h pregermination incubation. The potential of some physical factors in combination with this fungal concentration in enhancing AGP was evaluated. The treatments were as follows: (i) hot water scarification at 30°C, 50°C, 80°C and 100°C plus A niger; and (ii) nicking by decoating at either the micropylar or chalazal ends plus A niger. Micropylar scarification plus A niger gave the highest AGP (94%) followed by chalazal scarification plus A niger (86%) and hot water dip at 80°C + A niger (82%). The control seeds which were soaked in presterilised (by autoclaving at 121°C for 15 min) A niger spore suspension at 30°C gave zero germination. 相似文献
86.
87.
介绍了一种专为时分复用系统设计的时院分配计算算法。这种算法中主要用到的技术是从一个话务矩阵的各行选出一个区别代表的系统方法。对于任何话务矩阵,这种算法的分配效率都能达到100%,所产生的模式矩阵个数最多为n2-2n+2个(对于n×n矩阵)。 相似文献
88.
An integral method is investigated and developed in the current work. The effects of the parameters of inlet distortions
on the trend of downstream flow feature in compressor are simulated. Other than the drag-to-lift ratio of the blade and the
inlet incidence angle, it is found that the distorted inlet velocity is another essential parameter to control the distortion
in propagation. Based on this study, a novel critical distortion line and corresponding critical distortion factor are proposed
to express the effect of the two essential inlet parameters on the propagation of distortion, namely, the inlet incidence
angle and the distorted inlet velocity. From the viewpoint of compressor efficiency, the propagation of inlet flow distortion
is further described by a compressor critical performance and its critical characteristic. The results present a useful physical
insight to an axial flow compressor behavior and asymptotic behavior of the propagation of inlet distortion, and confirm the
active role of compressor in determining the velocity distribution when compressor responds to an inlet flow distortion.
Received: 20 December 2001 / Accepted: 21 August 2002
The authors would like to thank HQ RSAF for permission to publish this work, their financial support and encouragement. The
first author wants to acknowledge Prof. Frank Marble of California Institute of Technology, for bringing the problem to the
author's attention and for his helpful discussion. 相似文献
89.
介绍了一种烟道气中SO2在线检测系统,该系统可以实现24h不间断地监测烟道气中SO2的体积分数和质量浓度,同时将信息经网络传送给环保有关部门,具有一定的新颖性、可靠性、准确性。 相似文献
90.
STEFAN KASAPIS 《International Journal of Food Science & Technology》1994,29(1):29-38
The physical properties of the capsular polysaccharide of Rhizobium Trifolii (CPS) were investigated. Viscosity measurements provided information about the hydrodynamic volume of single coils, the perturbation of solvent flow and the shear-thinning behaviour of concentrated solutions. Changes in chain geometry and the development of an intermolecular network as a function of temperature were monitored using the techniques of optical rotation and dynamic oscillation. Finally, analysis of calorimetric thermograms elucidated the type of interactions between CPS and the bacterial levan. Overall, the Rhizobium polysaccharide was found to form thermally-reversible gels at an extremely low 'minimum critical gelling concentration' (co ∼ 0.35gl-1 ). At temperatures above the gel melting point (∼ 48°C), however, the compact polymer coils entangled at comparatively high concentrations (about 60 times higher than co ). In the presence of a highly branched levan, the thermal stability of ordered CPS structures increased as a consequence of thermodynamic incompatibility between the two polymers. 相似文献