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1.
在线浓缩-流动注射分光光度法测定海水中痕量的镉   总被引:3,自引:0,他引:3  
本文针对海水中镉含量低、海水基体干扰严重等特点,建立了在线浓缩一流动注射分光光度法测定海水中痕量镉的新方法。优化了Cd(Ⅱ)的显色条件、浓缩条件和解吸条件,在最佳检测条件下,Cd(Ⅱ)的检出限为0.02μg/L,线性范围为0.05~2μg/L,相对标准偏差RSD为2.74%(n=g,Ccd(Ⅱ)=1μg/L)。将该方法应用于实际海水中Cd(Ⅱ)的测定。结果满意。  相似文献   

2.
2015年及2016年的6月—8月,在北戴河近岸海域设立4个站点,进行海水叶绿素a及理化指标分析。监测结果显示,鸽子窝海域叶绿素a含量最高,平均值为8.93μg/L,老虎石海域含量最低,平均值为6.61μg/L;最大值发生在鸽子窝海域,为19.4μg/L,最小值发生在金沙滩海域,为2.01μg/L。总体上,北戴河近岸海域水质达到国家二类海水水质标准。与叶绿素a相关性显著的影响因素有无机氮、PO4-P、CODMn和pH值。  相似文献   

3.
研究采用分光光度法测定大气气溶胶中铬,测定波长为540nm.铬浓度在0.05 μ g/50mL~10μg/50mL范围内与吸光度呈良好的线性关系,大气气溶胶中铬的检出浓度为2.2×10-4 μg·m-3.当铬的浓度为0.07 μ g/50mL时,方法的相对标准偏差为12%(n=3),加标回收率为79%~113%.  相似文献   

4.
成都市幼儿体铅水平与环境铅污染的关系   总被引:4,自引:0,他引:4  
本文检测了成都市 50 1名 3~ 6岁儿童的发铅和血铅水平。发铅平均含量为 17 2 9± 9 70 μg/ g ,血铅平均浓度为 0 59± 0 33μmol/L( 12 3 81± 68 95μg/L)。 60 3%的儿童血铅浓度≥ 0 4 8μmol/L ( 10 0 μg/L) ;3 0 %的儿童血铅浓度≥ 1 4 4 μmol/L( 30 0 μg/L)。发铅与血铅无直线相关关系。市区儿童的发铅和血铅水平显著高于郊区儿童。大气铅测定显示市区铅污染重于郊区。讨论了铅污染的主要来源和儿童铅中毒的预防对策研究。  相似文献   

5.
还原-偶氮光度法测定废水中硝基苯的不确定度评估   总被引:1,自引:0,他引:1  
以还原-偶氮光度法测定了废水中硝基苯的浓度,分析了测量过程中4个主要部分的不确定度。样品中硝基苯的浓度为0.500μg/mL,取包含因子k=2(95%置信概率),扩展不确定度为U=0.032μg/mL,结果可表示为:(0.500±0.032)μg/mL。此方法测定硝基苯的不确定度的评析,有利于更准确地表示测量结果。  相似文献   

6.
聚乙烯醇(PVA)存在下[HgI4]2-与罗丹明B(RHB)形成配合物[HgI4]2--RHB-PVA,在波长610nm处有最大吸收,表观摩尔吸光系数ε = 6.02×105 L/( mol·cm).结合巯基棉(SCF)对汞的选择性吸附,实现了水样中痕量汞的分离、富集与测定.标准样品富集前后测定的相对标准偏差RSD分别为4.25%和7.40%(n=6).本法应用于三峡水域长江和嘉陵江江段中总汞的测定,回收率为90.6%~111.4%,最低检出浓度0.040μg/L,对比国控点原子荧光光谱分析法监测汞数据,结果令人满意.  相似文献   

7.
纳米零价铁去除磷酸盐机理研究   总被引:1,自引:0,他引:1  
纳米零价铁(nanoscale zero-valent iron,nZVI)颗粒具有独特核-壳结构,使其具有较强氧化还原特性,比表面积大和表面活性高等特点,因此被广泛用于不同环境介质中多种污染物的去除修复。本研究采用传统的液相化学还原法合成nZVI颗粒并用于去除水溶液中的磷酸盐。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线衍射仪(XRD)表征nZVI颗粒的性质。实验研究了nZVI投加量、PO3-4初始浓度、溶液初始pH值对nZVI去除PO3-4效率的影响及微米零价铁(micro-ZVI)和nZVI去除PO3-4的对比。实验结果表明,当PO3-4初始浓度为20mg/L时,随着nZVI投加量从200mg/L增加到1000mg/L,PO3-4去除效率从32.94%上升到90.17%;当nZVI投加量为600mg/L时,随着PO3-4初始浓度从10mg/L增加到100mg/L,PO3-4去除效率从87.33%下降到45.77%;当nZVI投加量为600mg/L且PO3-4初始浓度为20mg/L,溶液pH分别为3和4时,PO3-4去除效率分别为83.63%和92.36%;nZVI和mZVI投加量均为600mg/L且PO3-4初始浓度为10mg/L,nZVI的PO3-4去除率(87.33%)是mZVI(8.86%)的9.86倍。研究结果表明,nZVI能够高效去除水体中的磷酸盐,主要去除机理是吸附和化学沉淀的双重作用。  相似文献   

8.
本文建立了离子色谱法同时测定水中三价铬和六价铬的方法。样品中的三价铬经柱前衍生后,泵入分析柱,与样品中的六价铬分离,分离后的样品经在线柱后衍生,流入可变波长检测器,分别在365 nm和540 nm检测。利用正交实验找出最佳分析条件:水浴加热2 min,加热温度80℃,柱后衍生液流速1.1 ml/min。方法在10 min内完成水中三价铬和六价铬分析,三价铬和六价铬线性范围分别为0.05~10 mg/L和0.005~1 mg/L,方法检出限低,分别为18.1μg/L和0.267μg/L,精密度分别为1.16%(0.4 mg/L Cr3+,n=7)和3.07%(0.08 mg/L Cr6+,n=7),样品分析时的加标回收率在96%~102%之间。  相似文献   

9.
建立超高效液相色谱法(UPLC),测定桦褐孔菌中三种主要化合物原儿茶醛、丁香酸和(E)-4-(3,4-二羟基苯基)丁-3-烯-2-酮含量。采用UPLC法,色谱柱为CORTECS UPLC T3(2. 1mm×100mm,1. 6μm),流动相为乙腈—水(含0. 1%甲酸),柱温为40℃,流速为0. 4mL/min,进样量为1μL,检测波长为280nm。结果表明:原儿茶醛、丁香酸和(E)-4-(3,4-二羟基苯基)丁-3-烯-2-酮分别在0. 1953125—6. 25μg/m L(R2=1. 0000)、0. 1953125—6. 25μg/m L (R2=0.9998)、0. 1953125—6. 25μg/m L(R2=1. 0000)范围内线性关系良好,平均回收率(n=9)分别为98. 150%(RSD=1. 924%)、95. 787%(RSD=2. 487%)、100. 324%(RSD=1. 541%)。不同产地间的桦褐孔菌含量测定结果表明,三种化合物含量的差异较大,吉林长白山最高,俄罗斯西伯利亚次之,黑龙江大兴安岭最低。该方法操作简便、结果准确可靠、重现性好,可为桦褐孔菌的定量分析和质量评价提供科学的依据。  相似文献   

10.
本文讨论了一种采用酶标仪可同时快速测定水体中叶绿素a(chl a)和叶绿素b(chl b)的荧光光度法。该方法具备高通量(一批测样96个)、简便快速(100ms)、同时检测chl a和chl b的优点。实验范围内chl a和chl b的线性范围分别为0.7~4500μg/L和1.0~4500μg/L,检测限分别为0.04μg/L和0.06μg/L。该方法与传统可见分光光度法比较,其结果无显著性差异,检测限更低,在实际水样检测中得到较好应用。  相似文献   

11.
化学沉淀法处理高浓度氨氮废水的试验研究   总被引:1,自引:0,他引:1  
实验采用磷酸氨镁沉淀法(MAP法)去除垃圾渗滤液中的高浓度氨氮。通过对MgCl2+Na2HPO4^-、MgSO4+Na2HPO4、MgO+Na2HPO4、MgCl2+NaH2PO4、MgSO4+NaH2PO4和MgO+NaH2PO4等六种组合药剂去除氨氮效果的分析比较,得出MgCl2+Na2HPO4对氨氮的去除效果最好。继而对该组合药剂去除氨氮的影响因素进行了优化。结果表明:pH为9.0,反应时1.3为50min,n(Mg^2+):n(NH4^+):n(PO4^3-)为1.2:1:0.9时,氨氮可由原来的2100mg/L降低到317mg/L,去除率达84.9%.  相似文献   

12.
Information is needed on organic polyphosphates such as myo-inositol 1,2,3,5/4,6-hexakis dihydrogenphosphate or phytate (IP6) contribution to the sources and sinks of dissolved phosphorus (PO4-P) in the soil-manure-water system. Effects of Na+, Ca2+, Al3+, and Fe3+ and cation to IP6-P mole ratios on the enzymatic dephosphorylation of IP6 were studied to determine controlling mechanisms of dephosphorylation and persistence in manure. Phytate- and PO4-P were analyzed by high-performance liquid chromatography. Phytate dephosphorylation by Aspergillus ficuum (Reichardt) Henn. phytase EC 3.1.3.8 decreases by 50 +/- 3.6 and 40 +/- 4% at pH 4.5 and 6, respectively, as Ca2+ concentrations increase and cation to IP6-P mole ratios reach 6:6. Polyanionic IP6 has a high affinity for Al3+ and Fe3+ and reductions in dephosphorylation average 27 and 32% at a cation to IP6-P mole ratio of 1:6 for Al3+ and Fe3+, respectively, while reaching more than 99% at a mole ratio of 6:6. A phytase-hydrolyzable phosphorus (PHP) fraction is native to ruminant animal manure and is proportional to total solids (TS) concentration in 1 to 100 g L(-1) suspensions. Added phytase, in effect, increases water-extractable P content of manure and the risk of environmental P dispersion. As the bioavailability and ecological effect of IP6-P appear to be regulated not only by pH-controlled enzyme activity but also by the associated counterions, the differential protective effects of cations influence the accuracy of manure PHP fraction estimates and increase phytate resistance to enzymatic dephosphorylation that may lead to its persistence in manure.  相似文献   

13.
微波消解-原子荧光光谱法同时测定土壤中痕量砷和汞   总被引:3,自引:0,他引:3  
甘杰  许晶  余江  黄懿  胡军  罗岳平 《四川环境》2010,29(6):25-27
建立了微波消解—原子荧光光谱法同时测定土壤中痕量砷和汞的方法。通过对消解体系以及灯电流、载气流量、屏蔽气流量等仪器参数进行优化,确定了最佳实验条件。在优化的实验条件下,采用原子荧光光谱法同时测定砷和汞的检出限分别为0.02μg/L和0.01μg/L,线性范围分别为0~40μg/L和0~4μg/L,两元素的加标回收率在92%~102%之间,相对标准偏差砷为0.9%~3.1%,汞为1.5%~3.4%,完全适用于土壤环境样品的检测。  相似文献   

14.
Turf, including home lawns, roadsides, golf courses, parks, etc., is often the most intensively managed land use in the urban landscape. Substantial inputs of fertilizers and water to maintain turf systems have led to a perception that turf systems are a major contributor to nonpoint source water pollution. The primary objective of this study was to quantify nutrient (NO(3)-N, NH(4)-N, and PO(4)-P) transport in storm-generated surface runoff from a golf course. Storm event samples were collected for 5 yr (1 Apr. 1998-31 Mar. 2003) from the Morris Williams Municipal Golf Course in Austin, TX. Inflow and outflow samples were collected from a stream that transected the golf course. One hundred fifteen runoff-producing precipitation events were measured. Median NO(3)-N and PO(4)-P concentrations at the outflow location were significantly (p < 0.05) greater than like concentrations measured at the inflow location; however, median outflow NH(4)-N concentration was significantly less than the median inflow concentration. Storm water runoff transported 1.2 kg NO(3)-N ha(-1) yr(-1), 0.23 kg NH(4)-N ha(-1) yr(-1), and 0.51 kg PO(4)-P ha(-1) yr(-1) from the course. These amounts represent approximately 3.3% of applied N and 6.2% of applied P over the contributing area for the same period. NO(3)-N transport in storm water runoff from this course does not pose a substantial environmental risk; however, the median PO(4)-P concentration exiting the course exceeded the USEPA recommendation of 0.1 mg L(-1) for streams not discharging into lakes. The PO(4)-P load measured in this study was comparable to soluble P rates measured from agricultural lands. The findings of this study emphasize the need to balance golf course fertility management with environmental risks, especially with respect to phosphorus.  相似文献   

15.
电感耦合等离子体原子发射光谱法测定食品中的铝   总被引:2,自引:0,他引:2  
杨定清  周娅  谢永红  罗晓梅  杨柳 《四川环境》2010,29(5):49-50,53
采用硝酸-高氯酸消解,电感耦合等离子体原子发射光谱法(ICP-AES法)测定食品中铝。结果表明,消解液可以直接用水定容上机;在A l浓度0~6mg/L范围内,相关系数R2=0.9996,优于国标比色法(0~3μg范围内,R2=0.981);该方法检出限为0.15mg/kg,极大地优于国标比色法(12.5 mg/kg);同一样品比较,本法RSD为5.8%,而国标比色法只能达10%;该法回收率在92%~97%之间,对GBW 10016茶叶标准物质测定值也在可接受范围内。  相似文献   

16.
建立了用于饮用水源水中61种挥发性有机物(VOCs)同时进行分析的气相-动态顶空进样-气相色谱-质谱法(D-HS-GC-MS),VOCs包括集中式生活饮用水地表水源地特定项目中的31种VOCs。用D-HS-GC-MS法对水样中VOCs进行分析,获得良好的标准曲线线性关系(均大于0.995,溴二氯甲烷除外),除乙醛、丙烯醛、丙烯腈和环氧氯丙烷的方法检出限分别为15 g/L、13 g/L、11 g/L和11 g/L外,其余VOCs的方法检出限均介于0.10~0.58 g/L,饮用水源水实际样品加标回收率和RSD分别为75.8%~116%和1.16%~21.6%(n=3)。气相-动态顶空进样法相对于常见的吹脱捕集法具有不直接接触样品的优势,避免了仪器被样品污染,用于饮用水源水中几十种VOCs的同时分析,在常规监测中可节省大量的人力物力投入。  相似文献   

17.
本文优化了加速溶剂萃取-超高效液相色谱测定土壤中苯并(a)芘的方法。样品经加速溶剂提取,逐级减压浓缩,0.25um滤膜过滤净化,超高效液相色谱(UPLC)测定。结果表明,标准溶液苯并(a)芘含量在3.125~lOOug/L范围内,苯并(a)芘的线性呈良好的线性关系,相关系数为0.9999,该方法的检出限和测定下限分别为0.015μg/kg和0.060μg/kg。将该方法用于4个地区土壤样品的测定,苯并(a)芘含量在0.04~6.26ug/kg之间,空白加标回收率为75.2%~96.4%之间,各项指控指标符合检测要求。  相似文献   

18.
Swine manure contains considerable amounts of total (P) and soluble phosphorus (PO(4)-P) which may increase the soil P content when applied in excess to crop requirements and, consequently, risk water eutrophication. The feasibility of using magnesium (Mg) from the by-product of electrolysis and foundries (BPEF) for the removal of P from liquid swine manure was studied by adding up to 3 g of Mg as BPEF per liter of nursery (NU) and grower-finisher (GF) swine manure in 25-L plastic buckets. Changes in P and other elements were monitored for up to 360 h. Small amounts of Mg as BPEF (0.5 and 1.0 g Mg L(-1) manure) reduced the total P concentration of the liquid fraction by 70 to 95% of both manure types with respect to the control treatment of mixed raw manure. A settling period of 8 h or more was necessary to significantly reduce the liquid fraction's total P concentration for both manure types. Reduction of PO(4)-P varied from 96 to 100% in the liquid fractions for both manure types, which along with natural settling, explains most of the total P reduction in that fraction. The addition of BPEF did not influence the N content of manure. The low P liquid fraction can be safely applied to saturated P soils whereas the high P solid fraction offers the opportunity of transporting manure to agricultural soils deficient in P. Since N is conserved, both liquid and solid fractions could be valuable fertilizer manure by-products.  相似文献   

19.
Surface-applied biosolids, the option most often used on range-lands, can increase the concentration of macronutrients and trace elements in the runoff water and can potentially produce eutrophication or contamination of surface waters. In this study, the effects of postapplication age of biosolids (18, 12, 6, and 0.5 mo) and rate of application (0, 7, 18, 34, and 90 Mg ha(-1)) on the quality of runoff water from shrubland and grassland soils were assessed. Between July and October 1996 simulated rainfall was applied to 0.50-m2 plots for 30 min at a rate of 160 mm h(-1). All of the runoff water was collected. The concentration of NH4+ -N, NO3- -N, PO4(3-)-P, total dissolved phosphorus (TDP), Cu, and Mn in the runoff water increased with rate of biosolids application and decreased with time of postapplication on the two soils. The highest PO4(3-)-P and NH4+ -N concentrations, 4.96 and 97 mg L(-1), respectively, were recorded in the grassland soil treated with 90 Mg ha(-1) of biosolids 0.5 mo postapplication. For the same soil, rate, and postapplication age of biosolids, Cu exceeded the upper limit (0.50 mg L(-1) in drinking water for livestock. Ammonium N and PO4(3-)-P should be the main compounds considered when surface-applying biosolids. Ammonium N at concentrations found in all biosolids-treated plots may affect the quality of livestock drinking water by causing taste and smell problems. Orthophosphate can contribute to eutrophication if the runoff from biosolids-treated areas enter surface waters.  相似文献   

20.
固相萃取-高效液相色谱法测定地表水中的溴氰菊酯   总被引:1,自引:0,他引:1  
彭蓉  程小艳  杨坪 《四川环境》2009,28(1):43-46
建立了固相萃取-高效液相色谱-二极管阵列扫描测定地表水中溴氰菊酯的方法。溴氰菊酯经C18小柱富集,用6.0mL二氯甲影丙酮(1:1,v/v)洗脱,氮吹转换溶剂为甲醇并定容至1mL后由高效液相色谱仪进行分析,检测波长为270hm,通过保留时间与特征紫外吸收图谱定性,外标法定量。方法检出限1.0ug/L;线性范围1.0~97.0ug,/L,/相关系数0.9999;相对标准偏差7.7%-17.5%(n=6);回收率在90.6%~111.9%。方法简单,快速,经济环保。  相似文献   

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