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21.
Monitoring water quality in reservoirs with IRS-1A-LISS-I 总被引:1,自引:1,他引:0
V. K. Choubey 《Water Resources Management》1994,8(2):121-136
An attempt has been made to quantify the relationship between the variation in IRS-IA-LISS-I (Indian Remote Sensing Satellite-1A Linear Imaging Self-Scanning System) radiance data and field measured change in secchi disc depth. Secchi disc depth was measured for 47 predetermined sampling locations on reservoir surface water. At extinction depth (secchi depth), water samples were collected from all the sampling locations. Suspended sediments of eight locations representing various reaches of the reservoir were selected for mineralogical, particle size and optical properties analysis. The LISS-I radiance value in band 1 (0.45–0.52µm) band 2 (0-52–0.59 µm) and band 3 (0.62–0.68 µm) were used in a regression analysis. The absorption infrared band 4 (0.77–0.86 µm) was not included in the analysis. In these, the dependable variable was secchi depth (SD) and the LISS-I-radiance data was the estimator variable. Forty-seven data sets of 20 October 1988 from Tawa reservoir surface water were used to obtain an estimator equation for SD. The verification of the estimator equation was tested by applying it to a data set of 21 measurements of 28 September 1988 for this reservoir. The coefficient of correlation between observed and estimated values for the 28 September 1988 data set wasr=0.92 for SD, indicating that the equation could accurately predict the water clarity (SD) for this reservoir on new occasions from IRS-IA-LISS-I spectral data. It is shown that mineral composition and optical properties of suspended sediments influence the reflected radiance of water quality. It is concluded that IRS-IA-LISS-I data provide a useful means of mapping water quality in reservoir. 相似文献
22.
In this study, the extent of the smear zone and the reduction of permeability and water content within the smear zone were investigated using a large-scale consolidometer. The installation of vertical drains by means of a mandrel causes significant disturbance of the subsoil surrounding the mandrel, resulting in a smear zone. The extent of the smear zone for Moruya clay (New South Wales, Australia) was estimated on the basis of normalized permeability and the reduction of water content by taking undisturbed samples (horizontally and vertically) at different locations. This study reveals that a significant reduction in water content and horizontal permeability takes place towards the drain, whereas the variation in the vertical permeability is negligible. The smear zone for Moruya clay was found to be 2.5 times the equivalent radius of the mandrel with the horizontal permeability varying from 1.09 to 1.64, an average of 1.34 times smaller than that of the undisturbed zone. Finally, a correlation between the permeability decrease and water content reduction within smear zone is proposed. 相似文献
23.
M. van der Kraan M.V. Fernandez Cid G.F. Woerlee W.J.T. Veugelers C.J. Peters G.J. Witkamp 《The Journal of Supercritical Fluids》2007,40(3):336-343
When natural fibres are dyed in supercritical carbon dioxide, the addition of a small amount of water increases coloration. For a process design it is important to know how much water has to be added to obtain a desired humidity of both textile and carbon dioxide. In this work a thermodynamic model is proposed to calculate the distribution of water over the textile phase and the supercritical phase as a function of pressure and temperature. The phase equilibrium is described with Raoult's law for non-ideal fluids. The absorbed water in the textile is a condensed phase and is modelled here as a non-ideal liquid, using the NRTL-equation. The non-ideality of the supercritical phase is described by a solubility enhancement factor, a new equation derived from statistical thermodynamics. Although the model is applied to cotton, viscose, silk and wool, it can be used for all water absorbing textiles. 相似文献
24.
淀粉丙烯酸接枝共聚吸水性树脂的研究进展 总被引:4,自引:0,他引:4
基于淀粉丙烯酸接枝共聚作为吸水性树脂具有环保和可生物降解的优良特性 ,目前 ,人们普遍关注的是如何提高其吸水性 ,抗温性 ,控制水份释放 ,压力下保水 ,以及电解液的吸收等。这些特性的改进将使产品的用途更为广泛 ,可以预见 ,淀粉丙烯酸接枝共聚作为吸水性树脂具有广阔的应用和发展前景。 相似文献
25.
简单介绍了欧盟新的共同对外贸易政策,包括市场准入战略,反倾销战略,新普惠制,统一技术标准与法规等。着重探讨了欧盟及共同对外贸易政策对我国石化行业造成的影响,并提出了应对策略。 相似文献
26.
The ozonation of aniline and anilinium ion in aqueous solution is investigated by determining the product distributions at different degrees of ozonation. Results indicate that anilinium ion, although less reactive than aniline, still has a remarkable reactivity towards ozone. The high anilinium ion reactivity and the observed product distributions are explained by assuming a radical mechanism for anilinium ion ozonation, whereas the behavior of aniline appears to be regulated mainly by the electrophilic ozonolysis mechanism. 相似文献
27.
This paper presents a new job release (JR) and scheduling methodology for one-stage parallel machines where sequence dependent setup times exist. A decision support system (DSS) based on job release is developed in order to enable the application of the methodology. First, mathematical programming models for both job release and job scheduling are devised. Then, due to the NP-hard nature of the problems, heuristics are proposed. As for the interaction between JR and scheduling, job scheduling is integrated with job release for the proposed heuristic solutions so that the capacity achievement provided by scheduling can be utilized for job release. In brief, product design characteristics oriented scheduling affects JR in the proposed approach. Moreover, value stream mapping (VSM) approach is used with the aim of stating the effect of the proposed methodology. Furthermore, the presented methodology was applied in a real life electric wire-harness production system. The application, based on 120-day production data, revealed that the proposed methodology provided 25% decrease in in-plant manufacturing lead time. 相似文献
28.
29.
我国烧碱生产技术概况 总被引:2,自引:0,他引:2
介绍了我国氯碱行业近几年来的发展情况:分析了我国烧碱生产的工艺技术现状。指出了为缩短与世界先进国家的差距需要加快开发关键设备和高性能的离子膜,加强管理。 相似文献
30.
关于煤化工前途的思考 总被引:3,自引:0,他引:3
对煤化工存在的问题做了分析,提出加大科研投入,获取自主知识产权,解决煤化工装置大型化、国产化,坑口气化,煤层气开发利用等煤化工重点问题,适合我国国情的煤化工将有良好的发展前景。 相似文献