X射线荧光光谱法测定土壤中微量元素铌

用粉未压片 X 射线荧光光谱的峰背比法,测定土壤中的微量元素铌,可基本消除基体影响,测定结果可满足一般土壤分析的要求,方法的变异系数为15.9％,检测限为5ppm,方法回收率91.5～108％。     

王水消解-冷原子荧光法测定土壤中的微量汞

建立了一种用王水水浴消解土壤样品一冷原子荧光测定土壤中的微量汞的分析方法。在优化实验条件下，方法的检出限为0.010 2ug／L；土壤中汞的回收率为95％-109％；测定下限为0.01ug／g。该方法具有操作简便、快速、准确、灵敏度高、重复性好等优点。     

TOA-MIBK萃取火焰原子吸收法同时测定土壤及蔬菜中铅镉

用氢氟酸、硝酸、高氯酸消化土壤样品，干灰化法消解蔬菜样品，用相对TOA-MIBK系统萃取，火焰原子吸收光谱法在同一条件下测定土壤、蔬菜中的铅、镉。在选定条件下，测得土壤铅、镉的相对标准偏差分别为2．3％～4．4％和3．0％～4.3％，蔬菜铅、镉的相对标准偏差分别为2．9％～4．5％和2．6％～4．5％；土壤铅、镉的回收率分别为96％～104％和95％～101％，蔬菜铅、镉的回收率分别为93％～102％92％104％。由测定结果得出离公路越近，蔬菜、土壤铅、镉含量越高。     

ICP-AES法测定土壤中铜、钒、镍和铬

在HNO3-H2O2-HF体系中微波消解土壤样品，用电感耦合等离子发射光谱法测定土壤中的铜、钒、镍、铬，设定了最佳的样品处理条件和仪器条件，该方法测定铜、钒、镍、铬检出限分别为0．01mg／kg、0．05mg／kg、0．5mg／kg、0．10mg／kg，回收率为98．4％～102．0％，方法简便、准确。     

X荧光光谱法测土壤参考样中的钛和铬

一、方法概述 X射线萤光光谱测定土壤中的许多微量元素具有方法简单、快速,无需破坏样品结构,无需进行化学前处理,且分析结果准确度较好的特点。使用峰背比法。即以散射辐射为内标校正土壤的基体效应,测定土壤中的微量元素     

固相萃取-气相色谱法测定土壤中毒死蜱和阿特拉津

应用带TSD检测器的气相色谱仪、CP—SIL19弹性石英毛细管柱,采用固相萃取技术提取土壤中毒死蜱和阿特拉津,对土壤中的毒死蜱和阿特拉津同时测定,回收率分别为81．5％～116．7％、80．3％～118．2％,方法的变异系数1．1％～4．8％和0．9％～5．3％,方法检出限分别为阿特拉津0．0006mg·kg^-1、毒死蜱0．0004mg·kg^-1。     

电镀废水污染区土壤重金属含量的测定及污染状况评价

运用原子吸收光谱法，测定了某地电镀废水污染区重金属污染土壤样品中cd、Ph、cu、zn4种元素的含量，RSD小于1％，加标回收率在92．78％-103．2％之间，表明测定结果可靠。依据测定数据、国家土壤环境质量二级标准、内梅罗指数法及潜在生态危害指数法，对电镀废水污染区土壤重金属污染状况进行评价。按二级标准评价结果为中度以上污染；以内梅罗综合污染指数法进行评价，土壤受到重度污染；用潜在生态危害指数法对污染生态风险进行评估，总潜在生态风险程度为重度。因此应对该区污染土壤进行治理。     

山东聊城市表层土壤有机氯农药残留研究

2008年麦收期间以网格布点法采集了聊城市137个土壤表层样品，利用ASE萃取技术，采用GC-ECD方法测定了样品中六六六（BHCs）、滴滴涕（DDTs）、六氯苯、艾氏剂、狄氏剂、异狄氏剂和七氯的检出率和残留量，并对土壤质量状况做了评价。结果表明，土壤中DDTs的检出率高达94.1％，其他6种有机氯农药（OCPs）均有不同程度检出。OCPs总残留量平均值为145.35μg／kg，其中DDTs占88.58％，是残留OCPs的主要成分。全部样点中BHCs的单因子污染指数Pi最大值为0.1，土壤未受BHCs污染；95％的样点中DDTs的Pi值小于1，土壤中DDTs含量未超标，而3％的样点Pi值小于2，土壤属轻度污染，2％的样点Pi值大于2，土壤属重度污染。     

油污染土壤中微生物量──碳的测定方法研究

用熏蒸-培养法测定油污染土壤中的微生物量─—碳。对某油田距采油井1、15、30m的土壤测定结果表明，受原油污染的土壤微生物量的大小随土壤含油量变化而变化。熏蒸-培养法受土壤水分状况影响较大，不适用于强酸性土壤及刚施用过大量有机肥的土壤，在测定性质差异很大的土壤时，必须分别测定转换系数Kc，才能得到可靠的结果。     

微波消解-ICP—MS测定土壤和水系沉积物中的重金属

建立了一种采用逆王水和氢氟酸的混合体系微波酸消解土壤与水系沉积物，电感耦合等离子体质谱法快速测定六种金属元素（As、Cd、Pb、Cu、Cr和Ni）含量的方法。本文研究了消解温度和消解时间对消解效果的影响。结果表明，在190℃下运行25分钟对土壤与水系沉积物中的六种金属元素均具有很好的消解能力，备元素的测定值与标准值相符。在对实际土壤与水系沉积物样品进行分析后得出采样区域的土壤与沉积物中这六种金属含量水平正常。     

石墨炉原子吸收法测定土壤金属元素的质量控制

为使石墨炉原子吸收法测金属元素准确可靠，对各测定程序和环节采取了消除干扰、测平行双样、测加标回收率、对照分析等措施。测定数据经统计分析，加标回收率在87．3％～115．2％范围内，平行双样相对偏差在12．3％以下，标准土样重复测定变异系数除镉（Cd）外均在5．9％以下，达到了分析测定的要求。     

Improving the accuracy of sediment-associated constituent concentrations in whole storm water samples by wet-sieving

Sand-sized particles (>63 microm) in whole storm water samples collected from urban runoff have the potential to produce data with substantial bias and/or poor precision both during sample splitting and laboratory analysis. New techniques were evaluated in an effort to overcome some of the limitations associated with sample splitting and analyzing whole storm water samples containing sand-sized particles. Wet-sieving separates sand-sized particles from a whole storm water sample. Once separated, both the sieved solids and the remaining aqueous (water suspension of particles less than 63 microm) samples were analyzed for total recoverable metals using a modification of USEPA Method 200.7. The modified version digests the entire sample, rather than an aliquot, of the sample. Using a total recoverable acid digestion on the entire contents of the sieved solid and aqueous samples improved the accuracy of the derived sediment-associated constituent concentrations. Concentration values of sieved solid and aqueous samples can later be summed to determine an event mean concentration.     

分光光度法测定氯化氢的实验条件改进

硫氰酸汞分光光度法测定大气中的氯化氢,所使用的硫氰酸汞-乙醇溶液配置时间长,浓度低,曲线线性不好,不适用于环境现场监测。通过对氯化氢测定过程中遇到的问题进行分析,对硫氰酸汞-乙醇溶液的配置方法进行改进,提高该溶液的浓度。实验证明,使用定性滤纸过滤后的0.40%硫氰酸汞-乙醇溶液,曲线线性关系好,标样准确度高,适用于现场监测分析。     

Determination of redox-sensitive phosphorus in field runoff without sediment preconcentration

Reduction-induced phosphorus (P) release from particles transported by field runoff has been poorly studied for want of a method that could be used for large surveys. To rectify this shortcoming, we modified the bicarbonate-dithionite (BD) extraction step of a sediment P speciation scheme for analyzing redox-sensitive P in runoff without sample preconcentration. The extraction comprised the addition of bicarbonate (pH buffer) and dithionite (reducing agent) into a runoff sample, 15 min of gentle shaking, filtration, and sample digestion. The samples were greatly reduced (Eh < -200 mV), and Fe and P were solubilized, but Al solubility was not increased. Phosphorus release from rock phosphates (calcium phosphates) was greater in the BD extraction than in water or bicarbonate solution, although no more than 0.2% of the total P was released. For runoff from a very fine Typic Cryaquept, the particulate phosphorus (PP) versus BD-PP relationship was linear up to a PP concentration of about 1.0 mg L(-1), but over the whole PP range studied (up to 2.6 mg L(-1)) somewhat better described by an exponential equation (BD-PP = 0.297 x PP(0.766); r2 = 0.91, n = 79). The minimum detectable value given by the method was relatively low, 0.023 mg L(-1), but reproducibility varied, with the coefficient of variation for 10 samples analyzed with 5 replicates ranging from 1.8 to 28.5%. Considering the variable reproducibility of the results and the lack of suitable reference material, the method needs further refinement and testing if it is to be used for quantitative determination of redox-sensitive P in runoff.     

分光光度法测定COD_(Cr)的试验条件选择

用分光光度法测定水中化学需氧量ＣＯＤＣｒ,通过正交试验选择氧化的最佳选择。试验结果表明对ＣＯＤＣｒ值为５０～１０００ｍｇ／Ｌ的水样：氧化剂Ｋ２Ｃｒ２Ｏ７用量为０．２０～０．４０ｍｏｌ／Ｌ,催化剂Ａｇ２ＳＯ４用量为１０ｇ／ＬＨ２ＳＯ４,消解时间１０ｍｉｎ,加热温度１８０℃。用ＣＯＤＣｒ为１３８ｍｇ／Ｌ的质控标样进行验证试验,其绝对误差为０．５～３．０ｍｇ／Ｌ。与标准方法相比用分光光度法测定ＣＯＤＣｒ具有分析误差小,省时、省力,节约药剂的特点。     

LINEAR PROGRAMMING APPLICATIONS IN WATER RESOURCES1

Applications of linear programming to water quality and water quantity problems are discussed, and a fairly comprehensive sample of recent literature in these areas is reviewed. Basic elements of linear programming are also discussed. Emphasis is placed on the elements of linear programming that make it a useful tool for analyzing water resource problems and the basic features of various water resource problems that render them amenable to meaningful analysis by linear programming.     

Are Small-Scale Irrigators Water Use Efficient? Evidence from Lake Naivasha Basin, Kenya

With increasing water scarcity and competing uses and users, water use efficiency is becoming increasingly important in many parts of developing countries. The lake Naivasha basin has an array of different water users and uses ranging from large scale export market agriculture, urban domestic water users to small holder farmers. The small scale farmers are located in the upper catchment areas and form the bulk of the users in terms of area and population. This study used farm household data to explore the overall technical efficiency, irrigation water use efficiency and establish the factors influencing water use efficiency among small scale farmers in the Lake Naivasha basin in Kenya. Data envelopment analysis, general algebraic and modeling system, and Tobit regression methods were used in analyzing cross sectional data from a sample of 201 small scale irrigation farmers in the lake Naivasha basin. The results showed that on average, the farmers achieved only 63 % technical efficiency and 31 % water use efficiency. This revealed that substantial inefficiencies occurred in farming operations among the sampled farmers. To improve water use efficiency, the study recommends that more emphasis be put on orienting farmers toward appropriate choice of irrigation technologies, appropriate choice of crop combinations in their farms, and the attainment of desirable levels of farm fragmentation.     

改进的QuEChERS-LC/MS/MS法快速检测蔬菜中7种农药残留

研究建立了蔬菜中农药多残留的快速检测QuEChERS-LC/MS/MS方法,优化了实验方案,样品以0.1%乙酸的乙腈（V/V）作为溶剂,Agilent Bond Elut提取试剂盒对样品进行1 min提取后,用C18和Agilent Bond Elut净化试剂盒净化。结果表明：7种农药的平均回收率为72%～127%,相对标准偏差为1.3%～16.3%,检出限为0.004～0.022 mg·kg^-1。该方法减少了溶剂用量,缩短了检测时间,每个样品溶剂用量仅为20 mL,每个样品的前处理费用大约为30元,一个实验人员每日可以处理50～60个蔬菜样品,真正实现农残的快速、简便、廉价、有效、灵敏、安全检测。     

环境监测中仪器分析方法不确定度的评估(Ⅱ)——原子吸收光谱分析中的测量不确定度

通过对环境样品分析中常用的原子吸收光谱法测量不确定度分量的分析,探讨了原子吸收光谱法测量不确定度的评估方法,针对不同环境基体样品、不同测定组分以及不同前处理方法的扩展不确定度进行了评定。原子吸收光谱分析中的测量不确定度主要来源于样品称量、消化液定容、仪器漂移及由吸收值通过标准曲线拟合求浓度部分,其中最主要的分量是由吸收值通过标准曲线拟合求样品溶液浓度时引起的测量不确定度。     

周庄旅游保护与开发研究

通过对周庄游客、居民抽样调查问卷与周庄历年旅游统计资料的分析，指出影响周庄旅游发展的有利因素及不利因素。针对影响周庄旅游发展的主要不利因素，在Sheela Agarwal的旅游产品重构理论的基础上提出了周庄旅游保护与发展的调控措施，即旅游产品转化和旅游空间转化两大策略，从而保证周庄旅游实现可持续发展。