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101.
102.
103.
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
104.
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
105.
在分析转向柱管花键部位应力集中情况的基础上,通过对某厂生产的转向柱管扭转破坏的试验研究,得到如下结论:①转向柱管的承载能力与其外花键齿与方向盘中心内花键齿之间的非接触区长度有关,以花键端部过渡圆弧的直径大小为宜;②安装方向盘总成时所施加在安装螺母上的拧紧力矩在70N.m左右时,转向柱管的承载能力最大。 相似文献
106.
Influence of Coherent Flow Structures on the Dynamics of Suspended Sediment Transport in Open-Channel Flow 总被引:1,自引:0,他引:1
The influence of suspended sediments on coherent flow structures has been studied by simultaneously measuring the longitudinal and vertical components of the instantaneous velocity vector and the instantaneous suspended particle concentration with an acoustic particle flux profiler. The measurements were carried out in clear water and in particle-laden open-channel flows. In both cases, they clearly show the predominance of ejection and sweep phases that are part of a burst cycle. The analysis further demonstrates the importance of the ejection and sweep phases in sediment resuspension and transport. Ejections pick up the sediment at the bed and carry it up through the water column close to the surface. It is shown that ejections and sweeps are in near equality in the near-bottom layer, whereas ejections clearly dominate in the remaining water column. The implications of these results for sediment transport dynamics are discussed. 相似文献
107.
A simple measuring procedure for low concentrations of H2 and H2S (at the level of ppm fractions) above the surface of water by using sensitive gas analyzers is suggested. The procedure is easily accomplished in conditions outside the laboratory (under field conditions). 相似文献
108.
E. V. Chernyshev E. N. Veprov V. A. Petrov S. L. Bogdanov T. Yu. Levina T. I. Petrova V. I. Kashinskii A. A. Zonov A. E. Verkhovskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(1):34-37
Results of a study of tube specimens cut from hot-water boilers show that film-forming octadecyl amine (ODA) used in the process
of preservation removes deposition from the surface of the metal. An ODA film is preserved on the surface after repeated washing
of the latter with hot water. The concentration of chlorides at the surface of the metal after treatment with ODA is lower
than before the treatment.
__________
Translated from élektricheskie Stantsii, No. 11, November 2005, pp. 15–18. 相似文献
109.
Stress Concentration Factors for a Circular Hole in Curved Beams Under Bending Loads 总被引:1,自引:0,他引:1
Abstract: As a contribution to the field of stress concentration studies, the case of circular hole in curved bar elements under bending is hereby studied. Trend values of stress concentration factors (SCF) are presented based on selected variables of the problem for two critical hole locations. The results will help to identify an SCF law for practical use by applying the statistical method of regression analysis. Two approximations obtained by means of computational methods are compared with those obtained by photoelastic experimental method. 相似文献
110.
To confirm the reliability of the theory of phase equibria of multicomponent polymer 1/multicomponent polymer 2 systems (i.e. quasi-binary systems) and the method of computer experiment based on this theory (Brit. Polym. J., 23 (1990)285; 23 (1990)299; Polym. Int., 29 (1992)219), could point curves (CPC), two-phase volume ratios ( R ) and critical solution points (CSP) have been determined experimentally for the quasi-binary mixtures of poly(ethylene oxide) (M¯w = 647, M¯w/M¯n = 1.15; M¯w and M¯n, the weight-average and numberaverage molecular weights, respectively) and poly(propylene oxide) (M¯w = 2028, M¯w/M¯n = 1.08; and Mw = 2987, Mw/Mn = 1.13). The hydroxyl end groups of both polymers were methoxylated in advance by the Cooper & Booth method (Polymer, 18 (1977)164). The thermodynamic interaction parameter between both polymers, χ12, and the concentration dependence parameters for the above quasi-binary systems were determined by the method proposed in a previous paper (Brit. Polym. J., 23 (1990)299). CPC, R and CSP values calculated on the basis of the theory are in good agreement with the values determined experimentally. 相似文献