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91.
结合2011年阿尔金山保护区水文地质科学考察工作,在对保护区地表水水系、水体类型及特征进行调查分析的基础上,采集了主要地表水体类型的水化学样本,对各样本中的阴阳离子含量、矿化度、pH等水化学指标进行了测试,分析了保护区主要地表水类型的水化学现状特征及其空间变化规律,并与历史调查资料进行了对比分析,探讨了近30年保护区地表水水化学特征发生的变化及主要原因。  相似文献   
92.
通过液体选择培养基、平板划线的方法从脱硫污泥中分离筛选出一株硫氧化细菌,并对其进行初步鉴定和生长特性的分析。结果表明,该细菌为化能自养型细菌,短杆状,大小为0.5~0.8 μm × 1.2~3.0 μm,革兰氏染色显阴性。以5%的接种量接种于富集培养基,S2-初始浓度为100 mg/L时,SOB在60 h内基本将还原态硫氧化完全,pH最低降到2左右。当溶液中有SO42-量积累和电导率升高后,对SOB氧化S2O32-过程有明显的抑制作用。该菌株对盐分的耐受值为7 650 μS/cm(以电导率计)。  相似文献   
93.
电化学氧化法处理高盐低COD污水研究   总被引:1,自引:0,他引:1  
文章针对高盐、低COD难降解污水进行电化学氧化法降解有机污染物的研究和试验,介绍了电化学氧化法降解COD、氨氮的原理,探讨了试验对COD、氨氮、聚合物的去除情况,分析了装置的经济性能及试验去除污染物的影响因素。  相似文献   
94.
盐度对刺参(Apostichopus japonicus)消化酶活力的影响   总被引:1,自引:0,他引:1  
以刺参(Apostichopus japonicus)为实验对象,分别设置5个盐度水平(23、26、29、32和35),采用酶活性分析的方法比较研究了在不同盐度的养殖环境下,刺参消化道内前肠和中肠不同部位蛋白酶、淀粉酶和脂肪酶3种消化酶活性的差异.结果表明,盐度对刺参消化酶活性影响显著(P<0.05).蛋白酶活力在盐度...  相似文献   
95.
Cell length of the diatom Cylindrotheca closterium (Ehr.) Reimann & Lewin was investigated on a fortnightly basis from January to April 2000 in a hyperhaline pond (Sardinia, Mediterranean Sea) and relationships, with changes in temperature, salinity, and nitrite concentrations were assessed using single and multiple regression analyses. Results of our study indicate that C. closterium cell size was inversely related to temperature changes, but that salinity and nitrite concentrations may have a major idiosyncratic effect on cell size variability.  相似文献   
96.
ABSTRACT: Salinity increases in water in some parts of the Nava-jo aquifer in southeastern Utah have been documented previously. The purpose of this paper is to use bromide, iodide, and chloride concentrations and del oxygen-18 and deuterium values in water from the study area to determine if oil-field brines (OFB) could be the source of increased salinity. Mixing-model results indicate that the bromide-to-chloride X 10,000 weight ratio characteristic of OFB in and outside the study area could not be causing the bromide depletion with increasing salinity in the Navajo aquifer. Mixing-model results indicate that a mixture of one percent OFB with 99 percent Navajo aquifer water would more than double the bromide-to-chloride weight ratio, instead of the observed decrease in the weight ratio with increasing chloride concentration. The trend of the mixing line representing the isotopically enriched samples from the Navajo aquifer does not indicate OFB as the source of isotopically enriched water; however, the simulated isotopic composition of injection water could be a salinity source. The lighter isotopic composition of OFB samples from the Aneth, Ratherford, White Mesa Unit, and McElmo Creek injection sites relative to the lsmay site is a result of continued recycling of injection water mixed with various proportions of isotopically lighter make-up water from the alluvial aquifer along the San Juan River. A mixing model using the isotopic composition of the simulated injection water suggests that enriched samples from the Navajo aquifer are composed of 36 to 75 percent of the simulated injection water. However, chloride concentrations predicted by the isotopic mixing model are up to 13.4 times larger than the measured chloride concentrations in isotopically enriched samples from the Navajo aquifer, indicating that injection water is not the source of increased salinity. Geochemical data consistently show that OFB and associated injection water from the Greater Aneth Oil Field are not the source of salinity increases in the Navajo aquifer.  相似文献   
97.
高盐度污水生物处理技术研究   总被引:9,自引:1,他引:8  
广西涠洲石油终端处理厂污水Cl 浓度在 110 0 0~ 12 0 0 0mg L ,平均为 113480mg L ,CODCr约为 15 0~ 4 0 0mg L ,属高盐度污水。通过对微生物进行驯化 ,仍可以用生化法处理。研究表明 :单一的厌氧生化法和好氧生化法处理污水均不能达标 ,而厌氧 好氧联合处理效果良好 ,出水水质稳定 ,出水CODCr为 14~ 6 7mg L ,可达到国家污水排放一级标准  相似文献   
98.
The consequences of anthropogenic impact on the water area of Amur Bay (the Sea of Japan) near Vladivostok include the eutrophication of coastal waters and littering with various objects used as artificial substrates, which protect sedentary animals from predators and contribute to the survival of their larvae. An indicator of eutrophication, the diatom Skeletonema costatum accounting for 81–96% of the total abundance of phytoplankton (Stonik and Selina, 1995), is consumed mainly by barnacles and the Pacific oyster. Thus, these animals gain an advantage in the colonization of artificial substrates. The results of the study suggest that eutrophication will lead to changes in the structure of the marine community.  相似文献   
99.
砂引草对滨海盐渍沙质土壤改良作用的研究   总被引:1,自引:0,他引:1  
以山东省威海市高区国际海水浴场的砂引草种群为研究对象,在其根系附近采集实验组土样并在周围的空白地面上采集对照组土样,测定几组能够说明其土质的数据,如土壤中空气的体积、土壤储水能力、有机质含量、土壤pH值等.通过将实验组与对照组进行比较,分析得出在滨海盐渍沙质土生长的砂引草可增加土壤中的空气和有机质含量,提高土壤颗粒的贮水能力,降低土壤pH值,同时还有绿化美观的效果,可为滨海的土质改良和绿化提供帮助.  相似文献   
100.
Kenney, Terry A. and Susan G. Buto, 2012. Evaluation of the Temporal Transferability of a Model Describing Dissolved Solids in Streams of the Upper Colorado River Basin. Journal of the American Water Resources Association (JAWRA) 48(5): 1041‐1053. DOI: 10.1111/j.1752‐1688.2012.00667.x Abstract: The application of a nonlinear least‐squares regression model describing the sources and transport of dissolved solids in streams of the Upper Colorado River Basin, and that was calibrated using data from water year 1991, was evaluated for use in predicting annual dissolved‐solids loads for the years 1974 through 1998. Simulations for each water year were run using annual climate data. To evaluate how well the model captures the observed annual variability across the basin, differences in predicted annual dissolved‐solids loads for each simulated year and 1991 were compared with differences in monitored annual loads. The temporal trend of the differences between predicted annual loads for the simulated years and the load for 1991 generally followed the trend of the monitored loads. The model appears to underpredict the largest annual loads and overpredict some of the smaller annual loads. An underprediction bias for wetter years was evident in the residuals as was an overprediction bias, to a lesser degree, for drier years. A regression analysis on the residuals suggests that the underprediction bias is associated with precipitation differences from 1991 and with previously defined downward trends in dissolved‐solids concentrations in the basin. In general, given the representative climatic conditions, the model adequately performs throughout the period examined. However, the model is most transferable to years with climatic conditions similar to 1991.  相似文献   
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