微波消解-流动注射分光光度法测定土壤中的总磷

采用热效率高的微波消解系统对土壤中的总磷进行消解,建立了微波消解-流动注射分光光度法测定土壤中总磷的方法,该方法对比HJ632-2011碱熔-钼锑抗分光光度法具有快速、简便、节约试剂等特点。本文用两种分析方法对实际土壤样品及标准样品进行定量测定,所得结果表明微波消解法能快速测定大量土壤样品的总磷。     

土壤中~(90)Sr快速分析方法初步研究

针对土壤中90Sr的快速分析方法进行了初步研究。借鉴总β的测量方式,将某核素迁移试验土壤样品直接铺至样品盘中进行β计数,结合样品的本底及探测效率,计算得到90Sr的活度浓度。与标准分析方法相比,两种方法所得测量结果间的相对标准偏差均控制在±15%以内,符合性较好,表明实验流程可以应用于此类样品90Sr的快速分析,满足应急情况下土壤中90Sr快速分析的要求。指出了该方法后续的研究方向,方法完善后可以应用于各类土壤样品中90Sr的快速分析。     

便携式XRF在快速评价矿区土壤修复效果中的应用探索

利用便携式重金属测定仪XRF对古叙硫铁矿区土壤中重金属含量测定的准确性进行研究。从土壤粒径、土壤含水率及检测角度等方面考察了对XRF检测值的影响,当样品粒径大于100目,含水率小于5%,且XRF垂直检测样品时,重复6次检测数据RSD最小。利用一元线性回归方程分析土壤原样及制样后XRF检测值与AAS/AFS检测值的相关性,结果表明重金属测定仪可定量检测原样中Pb、Cr、Ni、Cu等项目,定性检测Zn、As等项目。制样后XRF检测值均达到了定量水平,因此XRF可用于快速评价矿区土壤环境质量。     

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。     

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     

辽河三角洲土壤中石油类含量光谱分析初探

石油类物质对土壤的污染在油田区域内是一个普遍存在的问题。全面了解土壤中石油类物质含量是评价土壤石油污染的前提条件。对土壤石油污染评价的传统方法是在野外实地进行大量土壤采样,然后在试验室内分析石油类物质的含量。文中提出了利用少量野外土壤石油类物质样品,并结合野外光谱测量的方法对土壤中石油类物质进行分析的新方法。该方法应用于辽河三角洲,具有快速、省钱、省时、省力的特点,能对土壤中石油类物质含量进行宏观分析。满足了油田开发对土壤及环境污染评价的需要,并能为制定油田开发管理保护对策提供辅助信息。     

气质联用法同时测定土壤中多环芳烃和有机氯

建立了加速溶剂萃取和GC-MS同时检测土壤中多环芳烃和有机氯的方法,对提取条件和净化条件进行了优化。本方法可以实现多环芳烃和有机氯的完全分离,线性范围广,相关系数均大于0.999,检出限范围0.01~0.10 mg/kg,低于标准方法的检出限,适用于土壤中批量样品的快速、同时分析。     

两种土壤消解方法测定汞元素的验证

利用标准样品和某冶金小区土壤样品,对比了2种不同消解方法测定土壤中重金属汞元素的差异。将水浴消解、微波消解2种土壤消解预处理方法进行分析比较,分析2种消解方法的优点和缺点,并对消解样品测定重金属汞元素含量,验证了微波消解法预处理的实际样品值略高于水浴消解法预处理的实际样品值。     

检测实验室方法确认技术应用

基于实验室认可和资质认定评审准则对新开项目（或新建分析方法）必须要进行方法确认的要求,通过对标准土壤样品、能力验证样品、土壤及废弃泥浆样品分析对比,验证了原子荧光光谱法测定土壤中总砷方法的检出限、准确度、精密度、加标回收率等技术指标的符合性。     

SKALAR SAN++连续流动注射仪测定土壤中的挥发酚应用研究

随着石油化工、塑料、合成纤维、焦化等工业和农业的迅速发展,挥发酚类物质通过各种途径进入土壤和沉积物,污染情况日趋严重,土壤中挥发酚的监测显得越来越重要。建立了SKALAR SAN++连续流动注射仪测定土壤中的挥发酚的方法流程,方法的检出限为0. 053 mg/kg,测定下限为0. 21 mg/kg,对3种不同的土壤进行检测,测定标准偏差范围为0. 016～0. 146 mg/kg,变异系数小于6. 5%,对不同的实际土壤样品加标回收率范围在71. 0%～115. 0%之间,结果表明该方法灵敏度高,精密度和准确度均符合质量保证要求,该方法流程较简单,分析速度快、成本低,且对环境污染小,能针对大批量土壤样品连续快速测定。     

Spatial variation in 2-methyl-4-chlorophenoxyacetic acid mineralization and sorption in a sandy soil at field level

The phenoxyacetic acid herbicide MCPA (2-methyl-4-chlorophenoxyacetic acid) is frequently detected in groundwater beneath Danish agricultural fields. We investigated spatial variation in microbial MCPA mineralization potential in a flat agricultural field of fine sandy soil (USDA classification: Humic Dystrudept) located on the Yoldia plains of Northern Jutland, Denmark. Samples for determination of MCPA mineralization and sorption were collected from the Ap and Bs horizons at 51 sampling sites located in a 200 x 220 m grid. Spatial variation in sorption was low in both horizons (distribution coefficient, 0.36-4.16 L kg(-1)). Sorption correlated strongly with soil organic carbon content in both horizons (CV, 93 and 83%, respectively) and negatively with soil pH. [Ring-(14)C]-MCPA mineralized readily in the Ap horizon, with 49 to 62% of the (14)C-MCPA being converted to (14)CO(2) during the 67-d incubation period. With the subsoil, mineralization of (14)C-MCPA varied considerably between samples (0.5-72.8%). At neither depth was there correlation between (14)C-MCPA mineralization and sorption, soil pH, organic carbon content, clay content, number of colony-forming units (CFU), pseudomonad CFU, or any of the four microbial activity parameters measured. The presence of microbial genes encoding for the TfdA enzyme was quantified using real-time polymerase chain reaction. No correlation was found between MCPA mineralization potential and the natural background number of tfdA genes present in the soil samples. The degradation kinetics suggests that the high (14)C-MCPA mineralization rate detected in soil samples was linked to growth of the MCPA-degrading soil microbial community.     

土壤全氮量测定的方法改进研究

对经典的土壤全氮量测定方法进行改进,采用修正的凯氏法消煮-凯氏定氮仪蒸馏-纳氏试剂分光光度法比色测定土壤全氮量,测定含氮量为0.2~0.8g/kg土壤样品时,RSD为3.72%~8.67%,加标回收率为85.7%~98.7%,方法检出限为0.0125g/kg,具有较好的准确度和精密度。     

沙枣对滨海盐渍土的改良作用探究

实验以野生沙枣为研究对象，在根系附近采集实验组土样，在周围裸露土地上采集对照组土样。通过实验组与对照组的各项指标对照表明，在盐渍土上种植沙枣，不但可增加土壤中的含水量，而且可增加土壤中的空气体积和有机质含量，提高土壤中的K含量，降低土壤中pH值。沙枣对滨海盐渍土有着很好的改良效果和一定的经济效益。     

微波消解-原子荧光法测定土壤中锑与铋

采用微波消解和原子荧光技术测定土壤中锑、铋，预处理样品方便快捷，对环境污染小。方法的线性好，检出限、精密度和准确度符合测试要求，经国家有证标准物质验证，该法适用于土壤环境样品中锑和铋的监测。     

Occurrence and rates of terminal electron-accepting processes and recharge processes in petroleum hydrocarbon-contaminated subsurface

The occurrence and rates of terminal electron acceptor processes, and recharge processes in the unsaturated zone of a boreal site contaminated with petroleum hydrocarbons in the range C(10) to C(40) were examined. Soil microcosms were used to determine the rates of denitrification, iron (Fe) reduction, sulfate (SO(4)) reduction, and methanogenesis in two vertical soil profiles contaminated with oil, and in a noncontaminated reference sample. Furthermore, the abundances of the 16S rRNA genes belonging to Geobacteracaea in the samples were determined by real-time quantitative polymerase chain reaction (PCR). Analyses of ground water chemistry and soil gas composition were also performed together with continuous in situ monitoring of soil water and ground water chemistry. Several lines of evidence were obtained to demonstrate that both Fe reduction and methanogenesis played significant roles in the vertical profiles: Fe reduction rates up to 3.7 nmol h(-1) g(-1) were recorded and they correlated with the abundances of the Geobacteracaea 16S rRNA genes (range: 2.3 x 10(5) to 4.9 x 10(7) copies g(-1)). In the ground water, ferrous iron (Fe(2+)) concentration up to 55 mg L(-1) was measured. Methane production rates up to 2.5 nmol h(-1) g(-1) were obtained together with methane content up to 15% (vol/vol) in the soil gas. The continuous monitoring of soil water and ground water chemistry, microcosm experiments, and soil gas monitoring together demonstrated that the high microbial activity in the unsaturated zone resulted in rapid removal of oxygen from the infiltrating recharge thus leaving the anaerobic microbial processes dominant below 1.5 m depth both in the unsaturated and the saturated zones of the subsurface.     

Fate of polydimethylsilicone in biosolids-amended field plots

This research examined the fate of polydimethylsilicones (PDMS) in agricultural test plots amended with municipal biosolids. This 4 yr field study involved addition of 0, 15, and 100 Mg ha(-1) of municipal biosolids, which contained ambient concentrations of PDMS (1272 mg kg(-1) biosolids), to corn and soybean test plots. Soil samples collected at intermittent time intervals were analyzed for soil water, soil organic C, extractable PDMS and PDMS hydrolysis products. Above normal precipitation during the field study maintained soil water levels in excess of 100 g kg(-1) for most of the testing period of 1994-1998. Under these conditions half-lives for PDMS (based on field dissipation data) ranged from 876 to 1443 d. When biosolids amended soil samples were brought into the laboratory and subjected to more rapid drying, >80% of the PDMS was transformed to lower molecular weight hydrolysis products within 20 d. No difference in relative PDMS transformation rates were evident for soils that received PDMS in the form of a biosolids amendment or directly dosed to the soil (in the absence of biosolids) indicating little if any effect of direct PDMS-biosolids interactions on PDMS transformation rates. These results support that the overriding factor controlling the fate of PDMS in field soils is the soil moisture content.     

混合酸消解变化对土壤和沉积物中痕量硒分析影响

基于各3种采集环境样本、国家标准物质的土壤和沉积物,以当前环境监测行业常用的3种消解方法,探讨20种混合酸系统条件在消解条件变化中对复杂样本硒元素测定的影响。确定了最佳土壤和沉积物消解的组合为王水系统(盐酸∶硝酸∶氢氟酸∶过氧化氢∶高氯酸=3∶1∶1∶1∶1),各消解法的处理结果部分(n=5)∶水浴法消解时间仅需0.5h,总处理时间2h,准确度回收率达101%~104%,精密度RSD为1.95%~2.20%;电热板法总处理时间较长(7.5h),回收率106%,RSD偏高为8.46%,不推荐使用;微波法处理的总时间亦长达7.0h,回收率93.8%,但精密度亦偏高为8.24%,因此采用水浴法应用于环境样本的测定。该优化消解方法已直接应用于环境中农业、建筑用土和管道淤泥沉积物的3种样品类型前处理,利用同一优化条件即可快速对应土壤和沉积物性质样品,单次可批量处理72~84个样本,解决高通量样品痕量硒测定需求,提供环境污染监测和检测行业一参考依据。     

Near- and mid-infrared diffuse reflectance spectroscopy for measuring soil metal content

Rapid and nondestructive methods such as diffuse reflectance infrared spectroscopy provide potentially useful alternatives to time-consuming chemical methods of soil metal analysis. To assess the utility of near-infrared reflectance spectroscopy (NIRS) and diffuse mid-infrared reflectance spectroscopy (DRIFTS) for soil metal determination, 70 soil samples from the metal mining region of Tarnowskie Gory (Upper Silesia, Poland) were analyzed by both chemical and spectroscopic methods. Soils represented a wide range of pH (4.0-8.0), total carbon (5.1-73.2 g kg(-1)), and textural classes (from sand to silty clay loam). Soils had various contents of metals (14-4500 mg kg(-1) for Zn, 18-6530 mg kg(-1) for Pb, and 0.17-34 mg kg(-1) for Cd), ranging from natural background levels to high contents indicative of industrial contamination in the region. Soil samples were scanned at the wavelengths from 400 to 2498 nm (near-infrared region) and from 2500 to 25000 nm (mid-infrared region). Calibrations were developed using the one-out validation procedure under partial least squares (PLS) regression. Mid-infrared spectroscopy markedly outperformed NIRS. Iron, Cd, Cu, Ni, and Zn were successfully predicted using DRIFTS. The coefficients of determination (R(2)) between actual and predicted contents were 0.97, 0.94, 0.80, 0.99, and 0.96 for those metals, respectively. Only Pb content was predicted poorly. Calibrations using NIRS were less accurate. Root mean squared deviation (RMSD) values were from 1.27 (Pb) to 3.3 (Ni) times higher for NIRS than for DRIFTS. Results indicate that DRIFTS may be useful for accurate predictions of metals if samples originate from one region.     

高压闷罐与普通敝口容器消解土壤的对比实验研究

土壤（底质）环境样品的消解直接关系到测定结果的好坏，通过对比实验证明，高压闷罐法消解土壤（底质）比普通法具有消解完全，精密度和准确度高，重现性好等优点。