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51.
An airborne oceanographic lidar, with a frequency-tripled Q-switched Nd: YAG laser of 355 nm, has been designed to measure chlorophyll-a (Chl-a) concentration in the sea surface layer by the Ocean Remote Sensing Institute, OUC. The field experiment was carried out in the bay which is located south of the Liaodong Peninsula on the 10th of September 2005. After the flight, the raw data were processed and analyzed by the fluorescence-to-Raman ratio method with seawater attenuation coefficients calculated from signal profiles. The results of Chl-a concentration measurements by lidar are shown. The measurements in clear sea water were also compared with those of Chl-a concentration by a Moderate Resolution Imaging Spectroradiometer (MODIS). 相似文献
52.
水敏现象在石油、岩土和环境工程等领域广泛存在。有效地控制水敏现象的发生,不仅具有科学意义,还有一定的经济价值。本文在广泛查阅国内外研究成果的基础上,总结了水敏性在石油、岩土和环境工程方面应用的研究进展,并在此基础上提出了水敏性研究的发展方向。 相似文献
53.
The ground water flow path of the coastal area in the Yellow Sea, Korea, was interpreted using both the cross‐correlation analysis of hydraulic properties and the principal component analysis (PCA) of ground water chemistry. Data was obtained from observation wells in the underground liquefied petroleum gas (LPG) cavern constructed in the coastal area of Pyeongtaek. Cross‐correlation results showed that the operating pressure became more influenced on artificial factors for the variation of the groundwater level of the study area (45–66% of correlation coefficient) even though its affecting area was limited to the region with fractures or faults, and also showed that the delay time from the variation of operating pressure to the fluctuation of ground water level were relatively long periods (28–31 days). Three hydrogeochemical events (encrusted cement dissolution, host rock dissolution, and seawater intrusion), which were dominantly influenced on ground water quality, could be induced from the result of PCA. Quantitative evaluation for these events using the mixed equation with principal component scores suggest that the dissolution of encrusted cement materials was the predominant factor (39·0% of the total mixed proportion) to change the chemical composition of the seepage water during the ground water flow from the observation wells to the cavern. Integration of the statistical results also imply that ground water flow and hydrogeochemistry were predominantly affected by artificial factors such as cavern operation pressure and dissolution of encrusted cement materials, which were interdependent factors on the observation wells with high cross‐correlation coefficients and pH. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
54.
S.A. Crosby G.E. Millward E.I. Butler D.R. Turner M. Whitfield 《Estuarine, Coastal and Shelf Science》1984,19(2):257-270
The rate of uptake of phosphate onto synthetic Fe(III)- and Fe(II)-derived oxyhydroxides has been studied using reaction conditions similar to those encountered in natural waters. Kinetic analyses were carried out on the adsorption profiles and both first-order and second-order conditional rate constants were obtained. The temperature dependence of some of the rate constants was investigated and corresponding apparent activation energies calculated. Similar experiments and analyses were undertaken using Fe from natural sources and in general the conditional rate constants obtained in seawater were in agreement with the synthetic ones. The results of this study are of value when comparing the time scales of adsorption processes in natural waters with the time scales of mixing and advection. 相似文献
55.
This paper presents the general situation and key techniques of the drilling well M-1 in Matouying dry hot rock exploration hole, Leting, Tangshan, Hebei Province. A series of problems have been studied on the sea water drilling fluid, high temperature resistant fresh water drilling fluid, screw composite drilling technique, screw hole coring technology, and high temperature, thus solving the difficulty of sea water drilling fluid well protection, poor stability of drilling fluid under high temperature, and low efficiency in hot dry rock drilling and coring drilling to ensure the safety of the borehole and improve drilling efficiency. The high temperature resistant double condensation and double density cement slurry system and relevant technical measures are adopted to ensure the quality of cementing in the high temperature environment. Through the understanding and analysis of the strata in this area, this work provides valuable experience for drilling in the same strata in the future. The final hole depth of the M-1 well in Matouying is 4502. 11m, and hot dry rock with a temperature of 150t is found at 3965 m, which is the first hot dry rock well with a temperature of more than 150°C in the Beijing-Tianjin-Hebei region so far. © 2022 Editorial Board of Geology and Exploration. All rights reserved. 相似文献
56.
解决山东水资源短缺的对策 总被引:1,自引:0,他引:1
分析了山东省水资源现状和存在的主要问题,针对山东省水资源的严重短缺,提出了在传统用水、治水的基础上,实施人工增雨工程,直接利用海水和海水淡化与节约用水,建立节水型社会,调整水源结构,更新用水观念,开发新水源,综合用水,综合治水的路子,只有这样才能长久解决水危机。 相似文献
57.
Hamed Ketabchi Davood Mahmoodzadeh Behzad Ataie‐Ashtiani Adrian D. Werner Craig T. Simmons 《水文研究》2014,28(24):5938-5953
The fresh groundwater lenses (FGLs) of small islands can be highly vulnerable to climate change impacts, including sea‐level rise (SLR). Many real cases of atoll or sandy islands involve two‐layer hydrogeological conceptualizations. In this paper, the influential factors that affect FGLs in two‐layer small islands subject to SLR are investigated. An analytical solution describing FGLs in circular islands, composed of two geological layers, is developed for the simplified case of steady‐state and sharp‐interface conditions. An application of the developed model is demonstrated to estimate the FGL thickness of some real‐world islands by comparison with existing FGL thickness data. Furthermore, numerical modelling is applied to extend the analysis to consider dispersion effects and to confirm comparable results for both cases. Sensitivity analyses are used to assess the importance of land‐surface inundation caused by SLR, relative to other parameters (i.e. thickness of aquifer layers, hydraulic conductivity, recharge rate and land‐surface slope) that influence the FGL. Dimensionless parameters are used to generalize the findings. The results demonstrate that land‐surface inundation has a considerable impact on a FGL influenced by SLR, as expected, although the FGL volume is more sensitive to recharge, aquifer thickness and hydraulic conductivity than SLR impacts, considering typical parameter ranges. The methodology presented in this study provides water resource managers with a rapid‐assessment tool for evaluating the likely impacts of SLR and accompanying LSI on FGLs. 相似文献
58.
59.
应用模糊综合评价方法对大连臭水套海域疏浚物预选倾倒区的水质状况进行了评价,得到了有益的结论。 相似文献
60.
ImooUonONSCCisoneofthemosttwortantcausoffailureofstaiuleSsstalequipmentandfacilitieS.Studiesonunh0refacilitiesshowedthatanaddicchloridesolutionfilmcouldbefo~onthescheeofstalandthatstaiuleSSstalisinaCtivedissolutionstateinaedicchloridesolutionopinetal.,l99O;Gnanamoorthyetal.,l99O).ltisgenerallythoughtxthatSCCcannotoimrwhenthematerialisinaCtiveanodicdissolutionstate,soitsomcewithresultingcasualties(0ldfieldetal.,l99O)arousedattentiont0it.SomeSCCmeCanisrnsproposedpeuang,l988,Newmanctal.,… 相似文献