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1.
袁静  张益民  易强 《四川环境》2004,23(4):50-50,53
4-AAP萃取分光光度法测定挥发酚方法中,当挥发酚浓度超出校准曲线范围时,一般将水样稀释后重新分析测定。本文采用氯仿稀释萃取液测定吸光度,通过公式换算求得挥发酚浓度,试验表明,该方法准确可靠,操作简便快捷。  相似文献   

2.
用4—氨基安替比林萃取光度法测定水中挥发酚时,由于一些未知水样中酚含量较高,在预蒸馏水样稀释不当时,会出现显色后的萃取液颜色过深而无法比色测定的现象,此时酚浓度常常超出方法检测上限,若再重新取样耗时太多,采取将萃取液用氯仿再次稀释后比色测定的方法较好。试验证实,此法在超出检测上限的一定浓度范围内,显色反应仍是完全的,对显色后的萃取液,再次稀释测定是准确可靠的。  相似文献   

3.
通过理论分析和大量实验工作,找出了现行国家标准的悬浮物测定方法在测定高含盐污水时的不足之处,并且提出了准确的测定方法。新方法不仅能很好地反映水样的实际状况,而且可以推广应用于各种复杂水样的悬浮物的测定。  相似文献   

4.
文章通过空白、标准样品、实际样品测定实验及色度影响实验,对两种COD测定方法进行比对,验证方法的准确度和精确度。结果表明:哈希比色法在测定色度小的水样时,多次测定均值与重铬酸盐法测定结果相差不大;测定色度较大水样时,可以利用色度与测定结果偏差的相关性进行结果修正。  相似文献   

5.
生化需氧量的差压式测定方法的研究   总被引:1,自引:0,他引:1  
本文研究了用差压式直读测定实验装置测定生化需氧量(BOD5)的方法,验证了用该新技术测定BOD5的可行性。该方法操作简单、直观性好,简化了大量烦琐操作并可连续测定。经对水样分析并用标准稀释法的分析结果加以比较,获得良好的效果。  相似文献   

6.
本文介绍用对氨基二甲基苯胺光度法测定水样中硫化物时,如何降低空白值、提高硫化钠标液的稳定度以及提高酸化吹气回收率的原理和方法。  相似文献   

7.
对化学需氧量测定的不确定度进行合理评定,应充分考虑测定过程中的不确定度来源。建立了重铬酸钾法测定水样中化学需氧量不确定度的数学模型,对组成化学需氧量的各个因子的不确定度分量进行了详尽的分析和计算,得出了本次样品CODCr的测定结果为72.2mg/L,扩展不确定度为3.8mg/L。  相似文献   

8.
卢冬兴 《四川环境》2007,26(2):52-53
本文将标准加入法运用于分光光度分析中,排除了废水氨氮测定中复杂的基体干扰,操作简便,结果准确,适合于单个或小批量水样的直接测定。  相似文献   

9.
林伦志 《四川环境》1993,12(1):35-38
本文选用两种水质采样器,在升钟水库对比采样监测,对大型水库水质监测采样和溶解氧的测定进行讨论。证明一大型水库水质监测采样适宜采样器类型,以及溶解氧水样现场测定的好处。  相似文献   

10.
文章以悬浮物测定的国家标准GB 11901—89《水质悬浮物的测定重量法》为基础,加入水质浊度的概念展开了实验,结合玉门油田工业废水水样,讨论了过滤材料及其冲洗前处理(冲洗法)、水样放置时间、取样体积和浊度对悬浮物测定结果的影响。实验结果表明,在可接受误差范围内且考虑节约因素,选用滤纸进行测定;对预估测定结果偏小的水样应进行滤纸或滤膜冲洗前处理,对预估测定结果偏大的水样选用未冲洗滤纸或滤膜进行测定;水样放置时间要严格控制;取样体积直接影响悬浮物结果,对预估测定结果偏小的水样在不影响操作的情况下应尽量增大测量体积,保证结果精确性;浊度会影响测定结果,但效果微小,一般不考虑。  相似文献   

11.
在水质检测工作中,质量控制方法是确保检测数据准确的一种重要手段。当前水质检测实验室中常用的质控手段有盲样考核、平行测定、加标回收、比对试验、期间核查、相关性分析与质量监督六类,通过分析比较这些质控手段在分析检测中的差异及其对检测结果的影响,为提升水质检测工作质量,出具科学、公正的检测报告提供保障。  相似文献   

12.
扩散参数是影响物质在水中迁移的一个比较重要的参数,本论文通过自己设计的扩散装置,采用^87Sr(NO3)2作为示踪剂研究了锶元素在水环境中的扩散参数,同时还从理论计算上对试验结果进行了验证。  相似文献   

13.
A social cognition model of health behavior, the health belief model, was applied to the pro‐environmental behavior of private well water testing. Conceptualizing environmental behaviors as health behaviors may provide new insight into pro‐environmental behavior change. A groundwater education program was provided to K‐12 children throughout New England. Both child participants and their parents completed surveys pertaining to private well water behavior. Results indicate that perceived barriers and socioeconomic status significantly influenced past well water testing of parent participants. Perceived barriers included: participants' concern related to the cost of treating their water, and how a well water problem would influence their property value. Parent participants also indicated that they would perform future well water testing if they received a reminder cue to action that might include: getting a discount or reminder in the mail, if a well testing program was available, and state or local requirement. Our findings reinforce the need for continued private well water research and parallels to additional environmental behaviors.  相似文献   

14.
喷气式飞机设备可靠性综合试验剖面设计   总被引:1,自引:0,他引:1  
袁宏杰  党炜  杨贵超 《环境技术》2004,22(6):4-6,14
可靠性试验剖面是保证可靠性试验结果客观有效的重要条件。但GJB899中关于制定可靠性试验剖面的一些规定可操作性不强,无法满足实际工作的需要。为解决这些问题,研究了GJB899的有关内容,运用数学和空气动力学知识,对其中某些内容进行了优化和细化,总结了计算温度应力和动压的相关公式,以及温度应力加权的方法。使试验剖面更为合理。  相似文献   

15.
16.
研究了一种测定化学需氧量(COD Mn)的新型分光光度法。试验结果表明,该法简便快速、准确,精密度高,并且通过与国标法测定结果对比后确定该方法可用于自来水、饮用水等多种水体中COD Mn的测定。  相似文献   

17.
ABSTRACT: With the increased use of models in hydrologic design, there is an immediate need for a comprehensive comparison of hydrologic models, especially those intended for use at ungaged locations (i.e., where measured data are either not available or inadequate for model calibration). But some past comparisons of hydrologic models have used the same data base for both calibration and testing of the different models or implied that the results of model calibration are indicative of the accuracy at ungaged locations. This practice was examined using both the regression equation approach to peak discharge estimation and a unit hydrograph model that was intended for use in urban areas. The results suggested that the lack of data independence in the calibration and testing of regression equations may lead to both biased results and misleading statements about prediction accuracy. Additionally, although split-sample testing is recognized as desirable, the split-samples should be selected using a systematic-random sampling scheme, rather than random sampling, because random sampling with small samples may lead to a testing sample that is not representative of the population. A systematic-random sampling technique should lead to more valid conclusions about model reliability. For models like a unit hydrograph model, which are more complex and for which calibration is a more involved process, data independence is not as critical because the data fitting error variation is not as dominant as the error variation due to the calibration process and the inability of the model structure to conform with data variability.  相似文献   

18.
对水域生态系统的特点进行了介绍,指出了河流形态多样性是生物群落多样性的基础,提出了保持生态系统健康性与完整性的技术对策要点。  相似文献   

19.
对昂思多乡地区不同泉眼泉水的水质进行随机抽检,结果表明该区域内泉水的理化和微生物指标不仅符合国家生活饮用水的标准,同时符合天然饮用矿泉水的标准,属富锶型偏碱性中等软水,而且该地区泉水未受到有机物的污染,可将昂思多乡泉水做为优质的天然饮用矿泉水水源。  相似文献   

20.
Water availability risk is a local issue best understood with watershed‐scale quantification of both withdrawal and consumptive demands in the context of available supply. Collectively, all water use sectors must identify, understand, and respond to this risk. A highly visual and computationally robust decision support tool, Water Prism, quantitatively explores mitigation responses to water risk on both a facility‐level and basin‐aggregated basis. Water Prism examines a basin water balance for a 40‐ to 60‐year planning horizon, distinguishes among water use sectors, and accounts for ecosystem water needs. The 2012 Texas State Water Plan was used to apply Water Prism to the Big Cypress‐Sulphur Basin (Texas). The case study showed Water Prism to be an accurate and convenient tool to provide fine‐scale understanding of water use in the context of available supply, evaluate multi‐sector combinations of conservation strategies, and quantify the effects of future demands and water availability. Analyses demonstrated water availability risks for rivers and reservoirs can vary within a basin and must be calculated independently, simulation of water balance conditions can help illuminate potential impacts of increasing demands, and scenario simulations can be used to evaluate relative conservation efficacy of different water resource management strategies for each sector. Based on case study findings, Water Prism can serve as a useful assessment tool for regional water planners.  相似文献   

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