手持式X射线荧光光谱快速测定仪的实践应用评价及建议

手持式X射线荧光光谱仪(XRF)作为快速筛选重金属污染的手段在污染地块调查中广泛使用，但目前国内对XRF现场检测结果指导实验室筛选检测样品的可靠性研究缺乏。本文选择两个实际污染地块调查中的Cu、Pb、As、Ni、Cd和Hg6种重金属的XRF现场检测数据和实验室实测数据，采用一元线性拟合、Pearson相关、差异分析等手段对两种测试结果的一致性进行研究。结果表明，土壤中Cu、Pb、As和Ni4种金属的XRF测定值和实验室实测值具有显著相关性。Hg和Cd的XRF测定值显著高于实验室实测值，Cu、Pb、As和Ni XRF测定值较实验室实测值偏小的样品占比超过50%。6种重金属中Cu和Pb XRF测定值和实验室实测值的相关性及一元线性拟合结果更好(相关系数0.5～0.8,R~2>0.7)。Cu在XRF测定值大于1 000 mg/kg时与实验室实测值的拟合结果更好(R~2>0.7),As和Pb分别为XRF测定值在4.0～10 mg/kg和检出限～80 mg/kg范围时更好(R~2>0.8)。采用重金属筛选值的50%作为筛选实验室样品的标准时，XRF结果预测Cu、Pb和As超标样...     

一种简易的土壤透气速率测定方法及其应用

以原状土壤为试验对象,基于传统常压测定法设计出一种简单而准确的土壤透气速率测定方法。研究结果表明:该方法克服了传统常压测定法变压测定过程导致精度降低的问题,同时又具备简单易行的优点。运用该方法对长期定位试验土壤进行研究,发现长期配施有机无机肥可提高红壤稻田耕作层土壤透气速率,改良土壤通透性。     

一种适于PCR扩增的植物基因组快速提取新方法

在传统的碱裂解法提取基因组的基础上建立了一种新的基因组提取方法,这种方法对传统碱裂解制备基因组的方法进行优化,并且调整了中和剂的用量,引入异丙醇沉淀步骤对基因组进行纯化.实验证明这种方法扩大了碱裂解法制备基因组的适用范围,可直接从植物种子中快速提取出用于PCR(polymerasechain reaction)模板的基因组,对于600 bp以下的目的基因的检测效果显著,可以发现待测组分含量大于1%的样品.整个基因组提取时间控制在21 min,大大缩短了基因组提取时间,并且避免了酚/仿等对人体有害药品的使用.     

Development of Highly Selective and Efficient Prototype Sensor for Potential Application in Environmental Mercury Pollution Monitoring

Mercury (Hg) is an environmental pollutant which is detrimental to the health of living beings due to the toxicity in its all oxidation states. To control mercury pollution development of low cost, efficient and highly sensitive prototype mercury sensor remains a challenge. In the present work, we have proposed a low-cost prototype device based on silver nanoparticle-impregnated poly(vinyle alcohol) (PVA-Ag-NPs) nanocomposite thin film for mercury detection. The thin film, fabricated through a facile protocol, is shown to be a fast, efficient, and selective sensor for Hg²⁺ in aqueous medium with a detection limit of 10 ppb. We have utilized the aggregation and amalgamation of Ag-NPs with Hg²⁺ to develop the low-cost, highly efficient and feasible prototype mercury sensor. In the presence of Hg²⁺, the yellowish thin film turned into colourless due to the loss of intense surface plasmon resonance (SPR) absorption band of the silver nanoparticles (Ag-NPs) through aggregation and amalgamation with mercury. The developed sensor has high selectivity for Hg²⁺ ions over a wide range of other competing heavy metal ions, generally present in water of natural sources. The sensor response is found to be linear over the Hg²⁺ ion concentration regime from 10 ppb to 5 ppm. The developed sensor has shown to determine a trace Hg²⁺ ions in real water samples. Finally, using the proposed technique, we have developed a simple and inexpensive prototype device for monitoring in field environmental mercury pollution.

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乳制品中金黄色葡萄球菌PCR快速检测方法的建立

为快速检测乳制品中的金黄色葡萄球菌,本研究将纳米氢氧化钛和纳米氢氧化锆固定在滤纸片上以去除PCR反应抑制因子,并以Nuc为靶基因,建立一种无需样品前增菌的PCR快速检测方法,同时确定该方法的特异性、灵敏度和实用性,并评估该方法所用试剂在冷冻保存条件下的稳定性与实用性。结果表明,该PCR快速检测方法在检测97株目标菌及83株非目标菌后未出现假阳性或假阴性结果;该方法无需增菌处理,可在4 h内完成检测,检测限为10¹ CFU·25 g^-1或10¹ CFU·25 mL^-1;该方法与传统检测方法在实际乳制品样品中金黄色葡萄球菌的检出率及活菌检测率均一致(符合率100%);此外,该检测方法所用试剂在-20℃冷冻条件下可稳定保存至少12个月。综上所述,本研究建立的PCR快速检测方法特异性强、灵敏度高,且实用性良好,能有效去除样品基质中的PCR反应抑制因子,为乳制品中金黄色葡萄球菌的快速检测提供了参考依据。     

边缘效应应用与高产优质高效农业的发展

本文在总结边缘效应在农业生产中应用的情况及其产生效果的基础上,诊断继续拓广边缘效应的应用范围，将对高产优质高效农业的发展起着重要的作用，并指出了应用边缘效应时应注意的问题。     

Development of a Rapid LC-UV Method for the Investigation of Chemical and Metabolic Stability of Resveratrol Oligomers

Resveratrol, piceatannol, ε-viniferin, r-viniferin, r2-viniferin, and hopeaphenol are naturally occurring polyphenols, associated with potentially beneficial health effects. We developed a rapid liquid chromatography-ultraviolet detection (LC-UV) method, allowing for the simultaneous determination of these six compounds in biological samples in less than 2.5 min with standard LC equipment. Using this method for the assessment of the stability of the six analytes, we demonstrated that all stilbene polyphenols disappear rapidly in Dulbecco's modified Eagle's medium (e.g., half-life of resveratrol of 1 h). In contrast, the tetramer hopeaphenol was stable over the maximum incubation time of 72 h. In incubations with liver microsomes, ε-viniferin was rapidly glucuronidated, although to a lower extent than resveratrol. Hopeaphenol was not glucuronidated at all. Given that glucuronidation is the major metabolic pathway for polyphenols, hopeaphenol might exhibit significantly different pharmacokinetic properties than other polyphenols. When chemical and metabolic stability as well as biological activity of hopeaphenol are taken together, these findings warrant further investigation of this polyphenol.     

Digital Image Analysis Method for Rapid Measurement of Rice Degree of Milling

A digital image analysis method was developed to quickly and accurately measure the degree of milling (DOM) of rice. The digital image analysis method was statistically compared to a chemical analysis method for evaluating DOM, which consisted of measuring the surface lipids concentration (SLC) of milled rice. The surface lipid area percentage (SLAP) obtained by the image analysis method and the SLC obtained by chemical analysis had a high coefficient of determination using a quadratic model (R² = 0.9819) and using a logarithmic model (R² = 0.9703). The quadratic model and the logarithmic model were validated using the test data set and it received high coefficients of determination (R² = 0.9502 and R² = 0.9459, respectively).     

基于知识图谱分析的污染场地研究现状与发展趋势

为了解国内外污染场地相关研究状况,利用知识图谱工具VOSviewer、CiteSpace与HistCite对Web of Science核心合集数据库中发文的主要国家（地区）与机构、主要发文期刊、主要研究学者、重要文献和研究热点及其变化趋势等进行了计量分析。结果表明：（1）污染场地的研究涉及多个国家之间相互合作,发文机构中中国科学院、橡树岭国家实验室、滑铁卢大学、中国科学院大学与亥姆霍兹环境研究中心在该研究领域合作广泛。中国于近五年发文量超过美国,成为该领域发文最多的国家。（2）污染场地研究的主要发文期刊有Science of the Total Environment、Chemosphere、Environmental Science & Technology、Environmental Science and Pollution Research等,Naidu Ravi、Huang Guohe、Megharaj Mallavarapu等是该领域发文较多的研究学者。污染场地前十（TOP 10）的重要文献中,生物修复相关内容中占据了较高比例。（3）关键词聚类网络主要可分为污染场地生物毒理研究、土壤重金属及修复技术、污染物环境行为及水体修复、有机污染物生物修复等4类。（4）文献计量的结果分析表明土壤与地下水均为污染场地有害物质重要承载体,污染场地中土壤和地下水具有一体性,如果忽视了对地下水中污染的修复,则可能会导致场地的二次污染。重金属与多环芳烃是污染场地重点关注的污染物,我国目前重金属污染防治工作依然不容乐观,需要进一步加强和落实相应工作。寻求高效绿色的修复技术仍是解决污染场地问题的一个重点,提升微生物修复技术在有机污染场地修复中的应用价值,具有重要意义。     

Estimating Gaseous Mercury Emissions from Contaminated Floodplain Soils to the Atmosphere with Simple Field Measurement Techniques

The atmospheric emission of mercury (Hg) from a contaminatedwetlands system was studied in the floodplains along the riverElbe (Northern Germany). Results suggest that wetlands can beimportant transformation and phase transfer regions, linking theterrestrial, aquatic and atmospheric compartments of regionalbiogeochemical Hg cycles. Fluxes determined by flux chambermeasurements averaged 43 ± 5 ng m^-2 h^-1. Additionally,soil gas probe sampling was introduced to determine mercuryconcentrations in soil air. This technique shows some promise fordetecting and confining mercury contamination in soils. We alsopropose that measurements of total gaseous mercury (TGM) in soilair and the near-surface atmosphere, in combination with simplesoil physical parameters, may be suitable for calculatingsemiquantitative estimates of Hg evaporation from contaminatedsoils, based on laminar diffusion considerations. The results arecompared to other Hg flux measurements, and the advantages anddisadvantages of different approaches to quantify Hg emissionsfrom soils are discussed, especially with regard to possiblesystematic bias.     

Restoration of Soils and Vegetation on Reclamation Sites of the Kingisepp Phosphorite Field

Processes of initial soil formation were studied on long-term monitoring plots on dump rocks of quarry no. 3 of the Phosphorite production company in Kingisepp district of Leningrad oblast. Observations were performed in 1998, 2004, and 2014. It was shown that vegetation succession on the plots proceeds relatively quickly, and that the species composition of phytocenoses formed is typical of the areas with soddy-calcareous soils. Soil development proved to be correlated with the development of vegetation. Maximum changes in soil characteristics were observed with an increase in the density of forest vegetation and a decrease in the role of herbs. The molecular composition of humic acids in the studied soils remained stable; in particular, the ratio of aliphatic to alkyl aromatic fragments was virtually constant. This phenomenon could be due to the great amount of aliphatic components in the falloff of coniferous species subjected to humification.     

The Health Safety Programme for Workers Exposed to Elemental Mercury at the Mercury Mine in Idrija

In the Idrija Mine ore appears in two forms: the first as cinnabar (70%) and the second as native mercury (30%). In the area where native mercury was mined the concentrations of elemental mercury in the working and unventilated areas of the pit were very high, they periodically reached over and above 3 mg/m³ of air and most of the time exceeded the maximum acceptable levels of mercury vapours in the air (0.1 mg/m³). In such specific working conditions the number of workers suffering from the effects of mercury was very high. Work conditions in the mine urgently required more effective and preventative measures against exposure to mercury. The health and safety program includes monitoring of mercury concentrations, technical measures, personal protection, evaluation of individual external intensity of exposure and medical surveillance. The results were very successful, the number of mercun intoxicated workers dropped and after 1975 there were no more intoxicated workers, in spite of the increase in the number of areas worked where native mercury was present.     

因子分析法在汤河水库富营养化研究中的应用

水体富营养化是湖泊和水库面临的主要水质问题。运用综合营养状态指数法对汤河水库各断面营养水平进行评价，得出其目前的富营养化程度比较轻。因子分析法的应用表明，氮、磷和水温是汤河水库水体富营养化的主要影响因素。     

Application of the Regional Mercury Cycling Model (RMCM) to Predict the Fate and Remediation of Mercury in Onondaga Lake,New York

Onondaga Lake exhibits elevated concentrations of total mercury (HgT) and methyl-mercury (MeHg) in the water column, sediments and fish tissue due to industrial inputs, wastewater discharge and urban runoff. The steady-state Regional Mercury Cycling Model (RMCM) was calibrated to Onondaga Lake and applied to evaluate various remediation scenarios. Because of detailed data available for Onondaga Lake, the RMCM was effectively calibrated. Model predictions of water column and fish concentrations of Hg generally agreed with measured values. The model underestimated concentrations of Hg in sediments. Mass balance calculations show that inputs of HgT largely originate from tributary and wastewater inflows to the lake. In contrast, MeHg is largely derived from internal production. Model calculations suggest that elimination of Hg inputs from wastewater effluent and of drainage from a former chlor-alkali facility could greatly decrease Hg concentrations in fish tissue.     

推进农村信息化建设促进区域农村经济快速发展

当前,信息化已经成为最先进、最活跃的生产力,随着信息技术在农村的快速渗透和应用,农村信息化已经成为农村现代化的重要内容和标志。针对建设社会主义新农村、构建和谐社会的新任务,进一步加快农村信息化进程,着重分析了衡水市农村信息化的现状,探讨了推进衡水市农村信息化的举措。     

A Simple and Accurate Method to Measure Total Gaseous Mercury Concentrations in Unsaturated Soils

The goal of this project was to develop a method to measure the total gaseous mercury (TGM) concentrations in unsaturated soils. Existing methods did not allow for easy replication, were costly, and were more suited for other gases, such as CO₂, that do not react with collection surfaces. To overcome these problems, we developed a method that simultaneously collects up to ten soil pore air samples. We used a single mass flow controller, one pump, and two banks of rotameters to draw soil air out of the ground at 25?smL?min^?1 onto gold-coated quartz traps. Analysis of the gold traps was performed with a Tekran 2500 CVAFS mercury detector. The system was field tested at the Piney Reservoir Ambient Air Monitoring Station in western Maryland. Our system was relatively precise and accurate. For example, replicate TGM concentrations differed by less than 25% and recovery of known amounts of mercury were greater than 95%. Field measurements showed that the maximum soil pore air TGM concentrations, between 3 and 4?ng?m^?3, occurred at the Oe?CA soil horizon interface. At all other depths, the total mercury concentrations were lower than the ambient air concentrations of 1.8?ng?m^?3. We believe our new method can be used to precisely and accurately measure the TGM concentrations in unsaturated soils at multiple locations simultaneously.     

Application of Fuzzy Logic to Qualify the Environmental Impact in Abandoned Mining Sites

This work deals with the topic of qualification and prioritization of environmental impact in abandoned mining sites using fuzzy logic. It aims to classify old mining sites and describe their environmental impact through a numeric index. This is variable in the interval [0,1], and was named as index of environmental impact (I _EI). Its determination was made through a fuzzy inference system that allows the integration of several characterization components. The system was supported by data obtained in five sites in NW Portugal, which is a paradigmatic region regarding the variety of typical environmental problems provoked by old metallic mines. These sites may be considered environmental patterns as they represent such regional diversity. In a general way, the I _EI can be applied to other sites where the existence of abandoned mining structures generates environmental impact.     

Rapid and Inexpensive Steam Distillation Method for Routine Analysis of Inorganic Nitrogen in Alkaline Calcareous Soils

Determination of inorganic nitrogen (N) in soil is important in making N fertilizer recommendations for crops. To find a rapid, reliable, and economical method for the estimation of inorganic N in alkaline calcareous soils of Pakistan, three steam distillation methods were compared using soils varying in ammonium (NH₄) and nitrate (NO₃) N contents and other physicochemical properties. In the standard method, the soil sample is shaken with 2 N potassium chloride (KCl) for 1 h, and the extract is then analyzed by steam distillation. In the other two methods, the soil sample is distilled directly with either 2 N KCl or distilled/deionized water. Based on the results of the present work, a method that involves steam distillation with only distilled/deionized water and that requires half the quantity of magnesium oxide (MgO) of the standard method has been proposed, as all the three methods yielded identical results for NH₄- and NO₃-N contents. Being economical, the proposed method for inorganic N estimation by direct distillation of soil with distilled/deionized water deserves consideration for adoption by soil-testing laboratories.