土壤重金属检测方法汇总.doc

forming the Government, enterprises and the public forces and actively participate in, sharing a strong atmosphere. Comrades, do work in the countryside and five water treatment, three to split, is related to overall development, responsibility, task, departments at all levels must play more than spirit, do solid work, and difficult, and efforts to promote the work to a new level, South Gate of XX beauty to make new and greater contribution to the building! Research by the County, the County Government, the convening of this county, three, poverty and development, environmental protection, the main task is to 2016-these work arrangements. For a while, . . Gay also made an important speech, we must pay special attention to follow-up. The following, according to the citys plans and . . Comrade usual requirements of our work, I want to tell you three views: the first, on three last year, my County three has made certain achievements. Capital work is done using city funds . . Billion yuan, annual tasks . .%; only completion target . . Minutes, annual tasks . . rate, access to city-wide recruitment talent introduction . . Award recognized scientific and technological achievements . . , Cooperation of . . Innovation platforms . . Also complete tasks in the city. The overall three column in the city . . Name, did not enter the city in recognition of the results of this. This means we and other counties than there is room to continue the efforts. From each town in the County Street, allocusing on ways and means of improving and upgrading work, further development of three to split. (A) fully grasp no unauthorised created. The township no unauthorised created the existing building one household, one document survey and file storage work must be unconditional and full coverage. Main corridor leading to the town (road, river) village, the Central built-up area of the town on both sides must be to create a no unauthorised village. According to five hundred villages created and shanty towns, villages, old houses, reconstruction of old plant, expand create, upgrading creates files, the real no unauthorised village created into the benefit of the people of very good thing. (B) to strictly manage count as unauthorised controls. Promoting the new control work to move the center of gravity, management measures to the front, and earnestly pipes effectively. A strict new unauthorised network responsibility. Sectors such as land, housing and basic stations (stations) and the Township of grid accountability mechanisms must be strictly in accordance with the new regulatory requirements, effective implementation of the area of responsibility of the new inspections, suppression, demolition work to ensure that the new zero tolerance. Second, public security, water, electricity, water, oceans and fisheries, tourism collaboration, market supervision departments should strictly enforce the illegal construction of disposal of relevant provisions of the regulations, effective fulfilment of responsibilities, particularly in electricity and water supply, and other units may not be new illegal buildings to supply water and electricity supply. While more regulation to prevent personal privacy violations. Illicit trading in illegal construction in the Ministry of public security sector to strictly from the blow. Three is to create additional offence reporting system of incentives. According to building law and covers an area of nature, to report timely degree divided report grade, effective after the removal of certain incentives. (C) integrated implementation , building demolition, modification, use combination. Demolition is the means and purpose built is. To adhere to the building demolished, combination of construction and demolition waste, demolished with combined efforts to improve the scientific level of three to split; second, we must pay attention to three to split and five hundred and five water treatment, three of the four sides, the shackDistrict transformation, and dangerous old room transformation and two road sides, series work organic combined up, active do River, and along demolition work, and manpower advance village in the, and old residential demolition work, to improved masses housing conditions and live environment; three to put three modified a split as traditional low, and small, and bulk industry structure transformation upgrade of important initiatives to caught, speed up advance industry Park, effective optimization park environment土壤重金属检测方法汇总摘要：土壤重金属检测是土壤的常规监测项目之一。采用合理的土壤重金属检测方法，能快速有效地对土壤重金属检测和污染评价，并满足土壤的管理和决策需要。本文介绍了几种常用的土壤重金属检测方法，原子荧光光谱法，原子吸收光谱法，电感耦合等离子体发射光谱，激光诱导击穿光谱法和X射线荧光光谱，在介绍各个检测方法特性的同时，就灵敏度，测试范围，精确度，测试样品的数量等优缺点进行了对比。关键词：土壤；重金属；检测方法1.前言许多研究表明，种植物的质量安全与产地的土壤环境关系密切。重金属一般先进入土壤并积累，种植物通过根系从土壤中吸收，富集重金属，有时也通过叶片上的气孔从空气中吸收气态或尘态的重金属元素1。近几年，种植地因农药、肥料、生长素的大量施用及工业“三废”的污染，土壤重金属含量超标较严重且普遍，这不仅毒害土壤-植物系统，降低种植物品质，而且还会通过径流和淋洗作用污染地表水，尤其重要的是通过食物链的方式进入人体内，对于重金属的富集人体难以代谢，最终直接或间接危害人体器官的健康2。为此，解决这一难题，建设绿色食品和无公害食品生产基地，要求我们从土壤中的重金属检测分析抓起。本文介绍了土壤重金属的检测方法、并且对比各种方法优缺点。2土壤中重金属检测方法2.1原子荧光光谱法原子荧光光谱法是以原子在辐射能量分析的发射光谱分析法。利用激发光源发出的特征发射光照射一定浓度的待测元素的原子蒸气，使之产生原子荧光，在一定条件下，荧光强度与被测溶液中待测元素的浓度关系遵循Lambert-Beer定律3，通过测定荧光的强度即可求出待测样品中该元素的含量。原子荧光光谱法具有原子吸收和原子发射两种分析方法的优势4，并且克服了这2种方法在某些地方的不足。该法的优点是灵敏度高，目前已有20多种元素的检出限优于原子吸收光谱法和原子发射光谱法；谱线简单；在低浓度时校准曲线的线性范围宽达35个数量级，特别是用激光做激发光源时更佳，但其存在荧光淬灭效应，散射光干扰等问题5。该方法主要用于金属元素的测定，在环境科学、高纯物质、矿物、水质监控、生物制品和医学分析等方面有广泛的应用6。突出在土壤中的应用如何，以下各方法均是这个问题，相比之下2.5写的比较好应用原子荧光光谱法测定土壤的重金属快速准确，测定周期约为2小时，具有检出限低、精密度好，干扰少和操作简单方便，值得推广应用。2.2原子吸收光谱法原子吸收光谱法又称原子吸收分光光度分析法，是基于气态的基态原子外层电子对紫外光和可见光范围的相对应原子共振辐射线的吸收强度来定量被测元素含量为基础的分析方法，是一种测量特定气态原子对光辐射的吸收的方法7。其基本原理是从空心阴极灯或光源中发射出一束特定波长的入射光，通过原子化器中待测元素的原子蒸汽时，部分被吸收，透过的部分经分光系统和检测系统即可测得该特征谱线被吸收的程度即吸光度，根据吸光度与该元素的原子浓度成线性关系，即可求出待测物的含量8。原子吸收光谱法在农业方面，主要应用与土壤、肥料及植物中的中微量元素分析、水质分析、土壤重金属环境污染分析、土壤背景值调查及农业环境评价分析等方面。该方法的优点是：选择性强、灵敏度高、分析范围广、抗干扰能力强、精密度高9。其不足之处有多元素同时测定有困难，对非金属及难熔元素的测定尚有困难，对复杂样品分析干扰也较严重，石墨炉原子吸收分析的重现性较差10。2.3电感耦合等离子体发射光谱法电感耦合等离子体发射光谱是根据被测元素的原子或离子，在光源中被激发而产生特征辐射，通过判断这种特征辐射的存在及其强度的大小，对各元素进行定性和定量分析11。电感耦合等离子体发射光谱法应用于环境水样、土壤样品中的微量元素进行分析，在元素分析测试中的应用技术具有简便、快速、分析速度快；检出限低，多数可达0.005g/ml以下12；测量动态线性范围宽，一般可达56个数量级，可同时进行高含量元素和低含量元素的分析，可达到石墨炉原子吸收光谱仪的部分检出水平；可多种元素同时分析，可定性、定量分析金属元素，也可分析部分非金属元素，提高了分析效率，基体效应小，低背景干扰、高信噪比、精密度高、准确性好等优点13。2.4激光诱导击穿光谱法激光诱导击穿光谱技术是一种最为常用的激光烧蚀光谱分析技术。其工作原理是：激光经过会聚透镜会聚，高峰值功率密度使未知样品表面物质气化、电离，激发形成高温、高能等离子体（温度可达10000K），等离子体辐射出来的原子光谱和离子光谱被光学系统收集，通过输入光纤耦合到光谱仪的入射狭缝中，光谱数据通过数据采集控制器传输到计算机，研究该光谱就可以分析计算出被测物质的成分与浓度14。原子光谱和离子光谱的波长与特定元素是一一对应的，而且光谱信号强度与对应元素的含量具有一定的定量关系。因此该技术可以实时、快速地现化学元素的定性和定量分析15。激光诱导击穿光谱可以真正做到现场快速分析，无须进行样品预处理，分析方便，也不受研究对象的限制16。但是，其测量仪器成本较高，激光脉冲能量的起伏性，样品的不均匀性，样品的特性会直接影响测量的稳定性，也就是说研究样品的特性对结果的精确性影响较大17。在激光诱导击穿光谱土壤重金属污染物检测的研究中，在光源设计上采用光学反馈减少脉冲间能量波动，在数据处理上采用一系列激光能量起伏归一化校正技术，达到克服由于激光器能量起伏造成的影响；通过选择最佳的采样延迟时间，以保证所采集到信号谱的信噪比最大；选择合适的激光脉冲的峰值功率阈值，达到克服谱线饱和现象和避免自吸收效应的发生以获得多元素的同时分析；通过研究激光聚焦焦点与样品表面之间的距离与测得信号谱线的信噪比的关系，达到提高系统的信噪比。通过以上措施克服上述不利影响，实现了利用LIBS技术对土壤中Cd，Hg，As，Cr，Cu，Zn，Ni，Pb等成分的同时测量。2.5X射线荧光光谱法X射线荧光光谱技术是一种利用样品对X射线的吸收随样品中的成分及其多少变化而变化来定性或定量测定样品中成分的方法18。X射线荧光光谱仪在结构上基本由激发样品的光源、色散、探测、谱仪控制和数据处理等几部分组成。该X射线荧光光谱法和电感耦合等离子体质谱法、发射光谱法在元素分析结果之间的差异，结果显示它们的差异不显著。从检出限、准确度、精密度和回收率方面均能满足实验要求19。土壤重金属X射线荧光光谱非标样测试方法具有前处理简单，无需标准样品，对样品无污染、无破坏性，检测速度快、稳定性高、再现性好等优点20。此方法是对土壤重金属检测和污染评价快速有效的方法。完全能够满足土壤环境受到污染时急需的快速定性、定量排查土壤中有毒有害重金属元素的要求。3总结土壤重金属检测是一项长期的工作，要求各种检测手段向更高灵敏度、更高选择性、更方便快捷的方向发展，不断推出新的方法来解决遇到的新的分析问题。上述5种重金属的检测方法的优缺点如表。随着各种分析方法的建立和科学技术的不断进步，分析仪器逐渐由简单化向复杂化的方向发展，可以预见，各种分析仪器会向多功能、自动化、智能化以及小型化的方向发展，并且检测精度、灵敏度得到一定的提高，使得土壤环境检测变得更加简单准确。优点缺点原子荧光多元素同时分析，干扰少，操作简单，应用范围广存在荧光猝灭效应，散射光干扰等问题原子吸收选择性强，灵敏度高，分析范围广，抗干扰能力强，精密度高多元素同时分析有困难，重现性差，分析干扰也严重ICP-AES可多元素同时分析，基体效应小，低背景干扰，高信噪比，精密度高，准确性好灵敏度较低LIBS现场快速分析，无需样品预处理，不受研究对象限制，多元素同时分析成本较高，研究样品的特性对结果的精确性影响较大XRF无需标准样品，对样品无污染、无、破坏性，检测速度快、稳定性高、再线性好灵敏度较低文献参考1陈学明，朱阳春，伏小勇天水苹果园土壤重金属富集状况评价及来源分析J农业环境科学学报，2011，30(5)：893-8942荆旭慧，李恋卿，潘根兴不同环境下土壤作物系统中重金属元素迁移分配特点J生态环境，2007，16(3)：812-8133王小平，马以瑾，徐元春原子荧光光谱法测定不同产地茶叶中As,Se,Hg和Bi四种元素含量J光谱学与光谱分析，2008，28(7)：1656-16584宋国庆原子荧光光谱法在微量元素分析中的应用D河南：郑州大学，20055邬春华，吕元琦，袁倬斌微波消解原子荧光光谱法测定生物样品中砷汞J理化检验-化学分册，2006，42(1)：42-446王志嘉，尤海丹，吴志刚微波消解-原子荧光光谱法测定中药材中铅、镉、砷、汞、锑的含量J沈阳药科大学学报，2008，25(5)：388-3927李燕群原子吸收光谱法在重金属铅镉分析中的应用进展J冶金分析，2008，28(6)，33-378韩金土，刘彦明，王辉原子吸收光谱法测定清热解毒类中草药中的11种微量元素J光谱学与光谱分析，2006，10(10)：1932-19369王北洪，马智宏，付伟利密封高压消解罐消解-原子吸收光谱法测定土壤重金属J农业工程学报，2008，24(9)：255-25610范宏.原子吸收光谱法测定食用油中金属元素的含量及营养价值分析D河北：河北大学，2010，511乔爱香，曹磊等.干法灰化和微波消解-电感耦合等离子体发射光谱法测定植物样品中22个主次量元素J岩矿测试，2010，2：29-3312王国兴，徐玉宇等电感耦合等离子体发射光谱法测定红土镍矿中镍钴铜J岩矿测试，2011，10：572-57513赵庆令，李清彩电感耦合等离子体发射光谱发同时测定土壤样品中54种组分J岩矿测试，2011，2：75-7814王建伟等LIBS技术在土壤重金属污染快速测量中的应用J.化学进展，2008，20(7/8)：1165-117115王书言等浅谈弄产品中重金属检测技术发展J河南农业，2009，(4)：39-40 16鲁翠萍等土壤重金属铬元素的激光诱导击穿光谱定量分析研究J物理学报，2011，04(5)：20617LeeYI，SneddonJApplicationsoflaser-inducedbreakdownspectrometryJAppliedSpectroscReview，1997，32(3):18323518韩小元等X射线荧光光谱法表征薄膜进展J光谱学与光谱分析，2006，26(1)：15919梁述廷等X射线荧光光谱法同时测定土壤样品中碳氮等多元素J岩矿测试，2004，23(2)：10220张勤等X射线荧光光谱法测定土壤和水系沉积物等样品中碳、氮、氟、氯、硫、溴等42种主次和痕量元素J分析试验室，2008，27(11)：52所有进场钢材，挂有标牌，牌上印有厂标、钢号、炉罐（批）号、直径等标记并附有质量证明书；无质量证明书，不得入库；经检验合格后物资设备部方可收货，如发现不合格钢材，不得验收入库。合格钢材应分批验收入库。forming the Government, enterprises and the public forces and actively participate in, sharing a strong atmosphere. Comrades, do work in the countryside and five water treatment, three to split, is related to overall development, responsibility, task, departments at all levels must play more than spirit, do solid work, and difficult, and efforts to promote the work to a new level, South Gate of XX beauty to make new and greater contribution to the building! Research by the County, the County Government, the convening of this county, three, poverty and development, environmental protection, the main task is to 2016-these work arrangements. For a while, . . Gay also made an important speech, we must pay special attention to follow-up. The following, according to the citys plans and . . Comrade usual requirements of our work, I want to tell you three views: the first, on three last year, my County three has made certain achievements. Capital work is done using city funds . . Billion yuan, annual tasks . .%; only completion target . . Minutes, annual tasks . . rate, access to city-wide recruitment talent introduction . . Award recognized scientific and technological achievements . . , Cooperation of . . Innovation platforms . . Also complete tasks in the city. The overall three column in the city . . Name, did not enter the city in recognition of the results of this. This means we and other counties than there is room to continue the efforts. From each town in the County Street, alland improve idle land of utilization, real achieved environment improved and productivity development mutual promoting total win. Five, firmly implement, promoting work ahead, to create highlights. Third deployment, implementation of seven, then it is imperative to strengthen responsibility and improve the mechanisms and implementation. All localities and departments must be convinced that goals, going all out, mustering spirit, work together to ensure that this years objectives carry out tasks, at the forefront. First, we must strengthen the leadership to implement. Departments at all levels should always work and rural five water treatment, three to split in an important position, and carry the main responsibility, main leader personally, leaders arrested and layers of responsibility rank transmission pressure established hierarchical accountability, and work together to promote the work of the mechanism, a concerted effort pay attention to implementation. County nongban, flood, three to one down to further play a leading catch total, integrated and coordinated role of all kinds is long, Sheriff Inspector to effectively fulfill their responsibilities, formed the alignment on the fire line and management a lively situation. Second, we must strengthen the test implementation of the Governor. Role play the Governor got the baton, for agricultural and rural focus and five water treatment, three to split work, refine improve assessment methods and evaluation system, accurate assessment. Combined with dare play, tree benchmark style building five major operations, carry on and gain firsthand experience of supervision, in particular, to strengthen the focus on the long signs go left, names such as supervision, urged all levels longer on duty in place. Through the supervisory assessment, to promote habits, stimulating power. Third, we must strengthen implementation style. Departments at all levels to work in rural areas and five water treatment, three to split as training cadres for major platforms, compete against large examination room, inspection cadres work performance of the ring, water control and the Japanese pulled a workout, training, discovery and selection of cadres. Than good catch up, first to excellence-oriented. Party members and cadres at all levels must adhere to the rural, water control and the Japanese pulled a grass-roots, put down the shelf, leaned pragmatic style, the spirit of play, become a benchmark model. Four, we must strengthen propaganda implementation. Comprehensive utilization of micro-credit, micro-blogging, new media, mining, summarizing, good publicity work in the countryside and five water treatment, three to split advanced models, point to gather positive energy for the community to see the results of our work in time, increase public awareness, participation rates, satisfaction and support. Play gongqingfu, a mass organization and grass-roots such as schools, communityThe role of