Characterisation of soils with the use of instrumental techniques : a multivariate forensic study

The value of soil evidence in the forensic discipline is well known. However, it would be advantageous if an in-situ method was available that could record responses from tyre or shoe impressions in ground soil at the crime scene. The development of optical fibres and emerging portable NIR instruments has unveiled a potential methodology which could permit such a proposal. The NIR spectral region contains rich chemical information in the form of overtone and combination bands of the fundamental infrared absorptions and low-energy electronic transitions. This region has in the past, been perceived as being too complex for interpretation and consequently was scarcely utilized. The application of NIR in the forensic discipline is virtually non-existent creating a vacancy for research in this area. NIR spectroscopy has great potential in the forensic discipline as it is simple, nondestructive and capable of rapidly providing information relating to chemical composition. The objective of this study is to investigate the ability of NIR spectroscopy combined with Chemometrics to discriminate between individual soils. A further objective is to apply the NIR process to a simulated forensic scenario where soil transfer occurs. NIR spectra were recorded from twenty-seven soils sampled from the Logan region in South-East Queensland, Australia. A series of three high quartz soils were mixed with three different kaolinites in varying ratios and NIR spectra collected. Spectra were also collected from six soils as the temperature of the soils was ramped from room temperature up to 6000C. Finally, a forensic scenario was simulated where the transferral of ground soil to shoe soles was investigated. Chemometrics methods such as the commonly known Principal Component Analysis (PCA), the less well known fuzzy clustering (FC) and ranking by means of multicriteria decision making (MCDM) methodology were employed to interpret the spectral results. All soils were characterised using Inductively Coupled Plasma Optical Emission Spectroscopy and X-Ray Diffractometry. Results were promising revealing NIR combined with Chemometrics is capable of discriminating between the various soils. Peak assignments were established by comparing the spectra of known minerals with the spectra collected from the soil samples. The temperature dependent NIR analysis confirmed the assignments of the absorptions due to adsorbed and molecular bound water. The relative intensities of the identified NIR absorptions reflected the quantitative XRD and ICP characterisation results. PCA and FC analysis of the raw soils in the initial NIR investigation revealed that the soils were primarily distinguished on the basis of their relative quartz and kaolinte contents, and to a lesser extent on the horizon from which they originated. Furthermore, PCA could distinguish between the three kaolinites used in the study, suggesting that the NIR spectral region was sensitive enough to contain information describing variation within kaolinite itself. The forensic scenario simulation PCA successfully discriminated between the ‘Backyard Soil’ and ‘Melcann® Sand’, as well as the two sampling methods employed. Further PCA exploration revealed that it was possible to distinguish between the various shoes used in the simulation. In addition, it was possible to establish association between specific sampling sites on the shoe with the corresponding site remaining in the impression. The forensic application revealed some limitations of the process relating to moisture content and homogeneity of the soil. These limitations can both be overcome by simple sampling practices and maintaining the original integrity of the soil. The results from the forensic scenario simulation proved that the concept shows great promise in the forensic discipline.

Retrieving clay minerals from stabilised soil compacts

Stabilised soil products such as stabilised soil blocks, rammed earth and stabilised adobe are being used for building construction since the last 6-7 decades. Major advantages of stabilised soil products include low embodied carbon, use of local materials, decentralized production, and easy to adjust the strength, texture, size and shape. Portland cement and lime represent the most commonly used stabilisers for stabilised soil products. The mechanism of strength development in cement and lime stabilised soils is distinctly different. The paper presents results of scientific investigations pertaining to the status of clay minerals in the 28 day cured cement and lime stabilised soil compacts. XRD, SEM imaging, grain size distribution and Atterberg's limits of the ground stabilised soil products and the natural soil were determined. Results reveal that clay minerals can be retrieved from cement stabilised soil products, whereas in lime stabilised soil products clay minerals get consumed in the lime-clay reactions and negligible percentage of clay minerals are left in the stabilised soil compacts. The results of the present investigation clearly demonstrate that cement stabilisation is superior to lime stabilisation in retrieving the clay minerals from the stabilised soil compacts. (C) 2014 Elsevier B.V. All rights reserved.

Biotransformation and accumulation of arsenic in soil amended with seaweed

For many coastal regions of the world, it has been common practice to apply seaweed to the land as a soil improver and fertilizer. Seaweed is rich in arsenosugars and has a tissue concentration of arsenic up to 100 micro/g g(-1). These arsenic species are relatively nontoxic to humans; however, in the environment they may accumulate in the soil and decompose to more toxic arsenic species. The aim of this study was to determine the fate and biotransformation of these arsenosugars in soil using HPLC-ICP-MS analysis. Data from coastal soils currently manured with seaweeds were used to investigate if arsenic was accumulating in these soils. Long-term application of seaweed increased arsenic concentrations in these soils up to 10-fold (0.35 mg of As kg(-1) for nonagronomic peat, 4.3 mg of As kg(-1) for seaweed-amended peat). The biotransformation of arsenic was studied in microcosm experiments in which a sandy (machair) soil, traditionally manured with seaweed, was amended with Laminaria digitata and Fucus vesiculosus. In both seaweed species, the arsenic occurs in the form of arsenosugars (85%). The application of 50 g of seaweed to 1 kg of soil leads to an increase of arsenic in the soils, and the dominating species found in the soil pore water were dimethylarsinic acid (DMA(V)) and the inorganic species arsenate (As(V)) and arsenite (As(III)) after the initial appearance of arsenosugars. A proposed decomposition pathway of arsenosugars is discussed in which the arsenosugars are transformed to DMA(V) and further to inorganic arsenic without appreciable amounts of methylarsonic acid (MA(V)). Commercially available seaweed-based fertilizers contain arsenic concentration between 10 and 50 mg kg(-1). The arsenic species in these fertilizers depends on the manufacturing procedure. Some contain mainly arsenosugars while others contain mainly DMA(V) and inorganic arsenic. With the application rates suggested by the manufacturers, the application of these fertilizers is 2 orders of magnitude lower than the maximum permissible sewage sludge load for arsenic (varies from 0.025 kg ha(-1) yr(-1) in Styria, Austria, to 0.7 kg ha(-1) yr(-1) in the U.K.), while a direct seaweed application would exceed the maximum arsenic load by at least a factor of 2.

Method development using ICP-MS and LA-ICP-MS and their application in environmental and material science

Within this PhD thesis several methods were developed and validated which can find applicationare suitable for environmental sample and material science and should be applicable for monitoring of particular radionuclides and the analysis of the chemical composition of construction materials in the frame of ESS project. The study demonstrated that ICP-MS is a powerful analytical technique for ultrasensitive determination of 129I, 90Sr and lanthanides in both artificial and environmental samples such as water and soil. In particular ICP-MS with collision cell allows measuring extremely low isotope ratios of iodine. It was demonstrated that isotope ratios of 129I/127I as low as 10-7 can be measured with an accuracy and precision suitable for distinguishing sample origins. ICP-MS with collision cell, in particular in combination with cool plasma conditions, reduces the influence of isobaric interferences on m/z = 90 and is therefore well-suited for 90Sr analysis in water samples. However, the applied ICP-CC-QMS in this work is limited for the measurement of 90Sr due to the tailing of 88Sr+ and in particular Daly detector noise. Hyphenation of capillary electrophoresis with ICP-MS was shown to resolve atomic ions of all lanthanides and polyatomic interferences. The elimination of polyatomic and isobaric ICP-MS interferences was accomplished without compromising the sensitivity by the use of a high resolution mode as available on ICP-SFMS. Combination of laser ablation with ICP-MS allowed direct micro and local uranium isotope ratio measurements at the ultratrace concentrations on the surface of biological samples. In particular, the application of a cooled laser ablation chamber improves the precision and accuracy of uranium isotopic ratios measurements in comparison to the non-cooled laser ablation chamber by up to one order of magnitude. In order to reduce the quantification problem, a mono gas on-line solution-based calibration was built based on the insertion of a microflow nebulizer DS-5 directly into the laser ablation chamber. A micro local method to determine the lateral element distribution on NiCrAlY-based alloy and coating after oxidation in air was tested and validated. Calibration procedures involving external calibration, quantification by relative sensitivity coefficients (RSCs) and solution-based calibration were investigated. The analytical method was validated by comparison of the LA-ICP-MS results with data acquired by EDX.

Near infrared spectroscopy as a rapid tool to measure volatile aroma compounds in Riesling wine: Possibilities and limits

Volatile chemical compounds responsible for the aroma of wine are derived from a number of different biochemical and chemical pathways. These chemical compounds are formed during grape berry metabolism, crushing of the berries, fermentation processes (i.e. yeast and malolactic bacteria) and also from the ageing and storage of wine. Not surprisingly, there are a large number of chemical classes of compounds found in wine which are present at varying concentrations (ng L-1 to mg L-1), exhibit differing potencies, and have a broad range of volatilities and boiling points. The aim of this work was to investigate the potential use of near infrared (NIR) spectroscopy combined with chemometrics as a rapid and low-cost technique to measure volatile compounds in Riesling wines. Samples of commercial Riesling wine were analyzed using an NIR instrument and volatile compounds by gas chromatography (GC) coupled with selected ion monitoring mass spectrometry. Correlation between the NIR and GC data were developed using partial least-squares (PLS) regression with full cross validation (leave one out). Coefficients of determination in cross validation (R 2) and the standard error in cross validation (SECV) were 0.74 (SECV: 313.6 μg L−1) for esters, 0.90 (SECV: 20.9 μg L−1) for monoterpenes and 0.80 (SECV: 1658 ?g L-1) for short-chain fatty acids. This study has shown that volatile chemical compounds present in wine can be measured by NIR spectroscopy. Further development with larger data sets will be required to test the predictive ability of the NIR calibration models developed.

全固态电流型氧传感器及Pt-Fe复合催化剂的研究

控制电位电解型即电流型气体传感器由于具有检测气体种类多、浓度范围宽、体积小、价格低、测量精度高、可用于现场直接检测等优点，在环境监测与安全生产等领域中得到了广泛应用。本文论述了纳米级铂、碳纳米管负载铂及铂铁催化剂的合成方法，并对其进行了物理化学表征和电化学研究，主要结果如下： 采用柠檬酸钠还原的方法，合成了纳米级铂催化剂。TEM和XRD测试表明，该球形多晶铂的粒径为2－5nm。用此种铂催化剂制备了离子交换膜电极复合体，并组装了全固态电流型氧传感器；在对低浓度氧气进行测试时，具有高的灵敏度、较短的响应时间、较低的底电流和噪声，且响应信号与氧气的浓度呈良好的线性关系。 1．利用空气氧化和硝酸相结合对多壁碳纳米管进行了纯化，并利用1:1的H2SO4-HNO3混酸使其表面羧基化，TEM和CV测试表明多壁碳纳米管达到了纯化和表面官能团化的目的。 2．利用喷雾冷却法制备了多壁碳纳米管负载的铂及铂铁合金纳米级催化剂复合体，并利用TEM、EDS、XRD、ICP等进行了表征；在循环伏安扫描中，铂铁合金催化剂呈现较高的比表面积。将多壁碳纳米管负载的铂及铂铁合金纳米级催化剂应用于C1有机小分子的电化学氧化研究中发现，铂铁合金催化剂具有较高的催化活性.

Ni-MH电池稀土AB_2型贮氢合金负极材料的研究

本文主要对稀土AB_2型贮氢合金用于Ni-MH电池负极材料的电化学性能进行了研究。结果表明，（一）通过优化合金组分，发现多相结构的 LaNi_(2-x)Al_x合金(0.15 ≤ x ≤ 0.25)显示突出的放电性能和长的循环寿命；（二）非化学计量比贮氢合金呈现更高的放电容量和满意的活化性能；（三）原材料的纯度对合金的电极性能影响甚微；（四）退火使合金的结构重整，但对合金电极的电化学性能不利；（五）长时间球磨可以促进活化，但导致电化学容量迅速衰减；短时间球磨大大增加放电容量和提高倍率放电性能；（六）合金电极高能辐照可以激活合金电极的表面活性，促进活化，有效的控制自放电；（七）随着在热碱液中浸泡时间的增加，合金电极的充放电性能得到明显的改善；（八）以镍粉为导电剂的合金电极比以铜粉为导电剂的合金电极有较好的综合电化学性能；（九）温度对合金的电极性能有很大影响。在30 ℃和40 ℃ 测试温度下所得的放电容量几乎相同，但在60 ℃和70 ℃放电容量开始减少。随着温度增加，电极的活化过程加速，高倍率放电能力略有所增加。合金电极呈现不理想的低温放电性能；（十）循环后合金电极的 XPS、XRD、ICP、SEM的图谱分析表明，LaNi_2基合金的腐蚀是造成容量衰减的主要原因，合金的本征衰退也可能是造成容量衰减的原因之一。

氟化物无机纳米粒子的制备及其稀土掺杂体系的光谱性质

对于纳米复合材料来说，首要解决的问题就是光散射。光散射现象主要是粒子尺寸以及粒子与基质材料折射率的差异引起的。对于小粒子（＜25nm），纳米粒子与基质材料之间的折射率差异不会造成明显的光散射现象，但对于较大粒子来说，为避免明显的光散射现象的发生，二者之间的折射必须吻合。由瑞利散射公式计算得知，当粒子直径大到100nm时，粒子与基质之间的折射率差值必须在0.02之内。因此，解决复合材料光散射问题有两种途径：尽量减小纳米粒子尺寸；选择折射率匹配良好的氟化物和聚合物分别作光学活性组分的基质和材料的基底材料。由于微乳液法合成纳米粒子条件温和、设备简单，所合成纳米粒子尺寸可控。本文首先研究了微乳液结构和性质，采用微乳液法合成氟化物纳米粒子，并研究了其稀土掺杂体系的光学性质。对于微乳液结构和性质的研究，本文绘制了十六烷基三甲基嗅化钱（CTAB）／正丁醇（n-C_4H_9OH）／正辛烷（n-C_8H_(18)）／水（或NH4F溶液、或Ba(NO_3)_2溶液、或KNO_3-Mg(NO_3)_2混合溶液）四组分微乳体系的三元相图，观察了电导率随水（或豁溶液）含量变化的规律，很好地印证了微乳液体系的相行为。实验发现，在这四个四元体系的相图中，Ba(NO_3)_2溶液体系的油包水区域面积最大，纯水体系水包油微乳区面积最小，我们分析认为水包油微乳区面积的变化是由于体系中加入离子后对表面活性剂阳离子的静电作用所引起的。采用十六烷基三甲基澳化按（CTAB）／正丁醇／正辛烷／水体系合成了KMgF_3以及KMgF_3:Eu~(2+)纳米粒子。XRD分析表明所合成纳米粒子为立方KMgF_3单相；环境扫描电子显微镜（ESEM）分析得到所合成KMgF_3:Eu~(2+)纳米粒子粒径约为20nm。KMgF_3:Eu~(2+)纳米粒子光谱研究发现其发射峰位于360nm附近，其激发峰位于250nm附近，较KMgF_3:Eu~(2+)单晶的激发峰峰蓝移了约80nm。对KMgF_3:Eu~(2+)纳米粒子激发峰蓝移的机理进行了初步探讨。采用CTAB/2-丁醇／水微乳体系合成出球形BaF_2纳米粒子，XRD和ICP数据显示样品为纯BaF_2相；FTIR谱图证明体系中没有有机物质的存在。将由纳米粒子分散到水中所形成的胶体滴到铜网上，干燥后发现所合成粒子有自组装的特性摘要且粒子自组装形状因粒子尺寸以及样品制备过程而异。粒子的自组装完全是自发的，没有任何的化学试剂对粒子进行包覆，也没对粒子施加除超声分散之外的任何外力。当将一滴胶体溶液直接滴到铜网上，干燥后我们得到粒子的圆形自组装，较大粒子分布在外围形成一个圆，较小粒子分布在圆的内部形成环；我们将一滴BaF_2纳米粒子胶体溶液滴加到铜网上，待干燥后滴加第二滴，重复此操作两次，这样铜网上共滴加的胶体溶液为3滴，此时我们得到粒子的双平行线型组装；直接滴加3滴BaF_2纳米粒子胶体溶液到铜网上，干燥后得粒子的桶状自组装。采用CTAB／正丁醇／正辛烷／水体系于35℃下合成带有枝晶的BaF_2纳米立方。这些枝晶生长在纳米立方的两个相邻面之间呈片状弧形。粉末XRD分析表明，体系为BaF_2单相且结晶良好；用扫描电子显微镜（SEM）对粒子进行分析发现，所得纳米立方边长为400-450nm；FTIR分析表明，经处理后样品中没有有机物质残存；对枝晶的能谱分析（EDS）分析表明，枝晶中只有Ba和F两种元素而未发现C元素存在。这说明，立方上所生长的枝晶为纯BaF_2产物而非有机物质所形成的。试验发现，所合成粒子的尺寸和形状依赖于反应温度和反应时间。采用士一述体系，于25℃下反应，可得到横截面边长40nm，长200nm的立方柱状纳米粒子，并且未见枝晶。从不同反应时间所合成粒子的形状上我们可以估计纳米立方以及枝晶的住：长过程。采用CTAB／正丁醇／正辛烷／水体系首次合成了BaF_2:Er纳米粒子，并研究了掺杂浓度对粒子红外发光的影响，XRD分析表明所合成BaF_2:Er纳米粒子为BaF_2立方相，物相纯净，结晶良好；TEM分析表明在掺杂浓度为6mol％时，粒子尺寸为15-20nm，士曾大粒子的掺杂浓度（8，10和12mol％）下，其尺寸和形状无明显改变，但粒子团聚现象严重。粒子在氢离子激光器488nm激发下的荧光（PL）光谱显示，随粒子掺杂浓度的增大，其发光强度增强，半峰宽加宽。研究了BoF_2:Er纳米粒子尺寸对其发光强度的影响，通过调节体系中水含量以达到控制粒子尺寸的目的。在体系中水含量。分别为5，8，15的条件「分别合成出平均粒径约为8，10和20.5nm的粒子。从粒子的激光粒度分布图中我们可得到粒子的平均尺寸。从粒子的XRD图中我们可以发现，随粒子粒径的减小，粉末的衍射峰出现偏移的情况。对于不同种纳米粒子，粒子粒径越小，衍射峰偏移越严重；对于相同的粒子，衍射角度越大，衍射峰偏移的越严重。从三种粒子的红峰的半峰宽和有效半峰宽越宽，对于8nm粒径的粒子，我们得到其最大半峰宽为145nm或有效半峰宽173nm。而且随粒子粒径的减小，其发射峰出现红移的现象。采用CTAB／正丁醇／正辛烷／水体系首次合成了CeF_3以及掺杂浓度为17，25，30，42和50mol％的CeF_3:Lu纳米粒子。XRD分析表明，所合成纳米粒子为CeF_3六角相，物相纯净，结晶良好，即使在高的掺杂浓度下（50mol％）体系中一也无其他杂质相的存在。环境扫描电子显微镜（ESEM-FEG）分析表明，所合成CeF_3纳米粒子粒径为巧一20nm，Lu的掺入对粒子的形状和尺寸影响不明显，但在较高的掺杂浓度下粒子团聚现象严重。粒子的荧光光谱表明，CeF_3以及Lu：CeF_3纳米粒子在254nm的激发波长下的发射光谱从290nm到400nm的宽带发射，发射峰位于325nm，较单晶体的发射峰红移约30nm；Lu的掺入有利于提高CeF_3纳米粒子的发光强度，随Lu掺入量的增大，粒子的发光强度出现先增后减的情况，在掺杂浓度为30mol％时，我们得到CeF_3纳米粒子的最大发射，但在50mol％的掺杂浓度下的粒子的发射强度仍要比未掺杂体系的发光强度要强。325nln监测粒子的激发光谱是从200nm到350nm的宽带吸收，激发峰峰位于260nm左右。比CeF_3单晶体的280nm激发峰蓝移了20nm左右。而且粒子的激发光谱中未见长波方向上的肩峰，说明粒子中CeF_3纳米粒子结晶良好，且体系中氧含量低。采用自创建一步原位聚合的方法合成了聚合物包覆的纳米粒子，并采用本体聚合的方法合成复合材料。综上所述，本文采用微乳液法合成了不同的氟化物纳米粒子，并研究了其稀土掺杂体系的光学特性，为聚合物基复合材料的制备以及应用奠定了可靠的实验基础。

Ti-V-Cr固溶体储氢合金的结构及电化学性能研究

本论文首先研究了Ni、Zr分别对Ti-V－Cr固溶体储氢合金中Cr和Ti部分取代的影响，得到了性能良好的Ti0．17Zr0．08V0．35Cr0．10Ni030基质合金。在此基础上进一步研究了入甄、B、Fe、Co、Al元素的添加或取代对基质合金的结构及电化学性能的影响。采用XRD、ICP、SEM一EDX、XPS、EIS、线性极化和阳极极化等表征手段对Ti一V－Cr固溶体储氢合金的结构及电化学性能进行分析和表征，主要结果如下：①Ti一V－Cr合金自身在碱性电解液中几乎无电化学活性。当用Ni部分取代Cr后，合金中出现具有电化学活性的第二相，其电化学性能得到有效地改善和提高。②Ti0.25-xZr_xV0.35Cr0.1Ni0.3（x＝0．05-0．15）合金主要是由bcc相和c14Laves相组成。随Zr含量从0．05增加到0．08，合金电极的放电容量和倍率放电能力增加；当x继续从0．08增加到0．15时，其变化较小。合金电极的电荷转移电阻随x增加而降低，当x在0．08到0．15之间变化时，电荷转移电阻变化也比较小。表明电荷转移电阻的大小与合金的电化学性能密切相关。③经过50次充、放电循环后，Tio．17zr"sV时scrol0Ni03。合金电极在303K和313K的放电容量能保持在90％以上；在70℃时的放电容量仍能达到275mA扮g。根据不同温度时的交换电流密度，计算了Ti。，17Zr008V时SCr川0Ni030合金电极表面电化学反应的表观活化能，其值约为50kJ／mol。④通过Nln、B、Fe、C。、AI对Tio．17zroosvo35Crol0Nio3。合金基质的添加与取代的研究，得到了具有高容量的储氢合金。其中Tio．17Zr008Vo35Cro．10Ni020Mnol。合金室温最高放电容量达到390n1A扮g；在253一343K的温度范围内，Tiol7Zr08V035Cr0JONioz5Mnoos合金具有高的放电容量，其容量在167一298mA树g之间变化，但是这些合金的稳定性有待进一步的提高。⑤合金充、放电过程中，晶格的扭曲和膨胀、Zr和V的溶解使得合金结构发生变化；合金的严重粉化及表面致密氧化膜的形成，是导致Ti一V－Cr合金电化学性能的衰减的主要原因。

Formation of Fe-oxyhydroxides from the East Pacific Rise near latitude 13 degrees N: Evidence from mineralogical and geochemical data

The mineralogical and geochemical characteristics of Fe-oxyhydroxide samples from one dredge station (long. 103 degrees 54.48'W, lat. 12 degrees 42.30'N, water depth 2655 m) on the East Pacific Rise near lat 13 degrees N were analyzed by XRD, ICP-AES, and ICP-MS. Most Fe-oxyhydroxides are amorphous, with a few sphalerite microlites. In comparison with Fe-oxyhydroxides from other fields, the variable ranges in the chemical composition of Fe-oxyhydroxide samples are very narrow; their Fe, Si, and Mn contents were 39.90%, 8.92%, and 1.59%, respectively; they have high Cu (0.88%-1.85%) and Co (65x10(-6)-704x10(-6)) contents, and contain Co+Cu+Zn+Ni > 1.01%. The trace-element (As, Co, Ni, Cu, Zn, Ba, Sr) and major-element (Fe, Ca, Al, Mg) contents of these samples are in the range of hydrothermal sulfide from the East Pacific Rise near 13 degrees N, reflecting that this type of Fe-oxyhydroxide constitutes a secondary oxidation product of hydrothermal sulfide. The Fe-oxyhydroxide samples from one dredge station on the East Pacific Rise near 13 degrees N are lower in Sigma REE (5.44x10(-6)-17.01x10(-6)), with a distinct negative Ce anomaly (0.12-0.28). The Fe-oxyhydroxide samples have similar chondrite-normalized rare-earth-element (REE) patterns to that of seawater, and they are very different from the REE composition characteristics of hydrothermal plume particles and hydrothermal fluids, showing that the REEs of Fe-oxyhydroxide are a major constituent of seawater and that the Fe-oxyhydroxides can become a sink of REE from seawater. The quick settling of hydrothermal plume particles resulted in the lower REE content and higher Mn content of these Fe-oxyhydroxides, which are captured in part of the V and P from seawater by adsorption. The Fe-oxyhydroxides from one dredge station on the East Pacific Rise near 13 degrees N were formed by secondary oxidation in a low temperature, oxygenated environment. In comparison with the elemental (Zn, Cd, Pb, Fe, Co, Cu) average content of hydrothermal sulfide samples from the East Pacific Rise near 13 degrees N, the Zn, Cd, and Pb contents of the Fe-oxyhydroxides are lower, and their Fe, Co, and Cu contents are higher.

Mordenite from Spain and its application as pozzolana

In Spain, natural zeolites have been only found in the volcanic areas of Canary Islands (San Gil, M.M., 1959). However, several years ago the study of the South Eastern region of continental Spain (Cabo de Gata) revealed the presence of a deposit of mordenite being industrially commercialized as bentonite. The deposit San José-Los Escullos is located in the concession registered as Los Murcianos, managed by Bentonitas Especiales, S.A. (BENESA) who was extracting bentonite while ignoring the presence of the zeolite. The name San José-Los Escullos refers to the discovery of mordenite in this deposit. The deposit is located in a volcanic area, constituted by pyroxenic andesites, breccias, tuffs, pyroclasts with andesitic and dacitic composition, largely altered by the hydrothermal solutions. The recent discovery of this zeolite with mordenite content up to 97%, has changed the initial vision about that deposit, and new possible uses of this mineral in the pozzolanic cement industry are foreseen. This work intends to give preliminary data on the characterization of this zeolite according to X-ray diffraction (XRD), ICP analyses, and scanning electron microscopy (SEM), as well as to emphasize the pozzolanic properties of this material, using both chemical and mechanical tests.

Efficient removal of paracetamol using LaCu1-xMxO3 (M=Mn, Ti) perovskites as heterogeneous Fenton-like catalysts

A series of perovskite-like oxides LaCu1-xMxO3 (M=Mn, Ti; 0.0 ⩽ x ⩽ 0.8) was prepared by amorphous citrate decomposition and characterized by XRD, ICP-OES and XPS techniques. The catalysts were tested in the Fenton-like degradation of paracetamol with H2O2, under mild reaction conditions, 25 °C and nearly neutral pH. Values of decomposition of paracetamol between 80 and 97% at 300 min were achieved for most of samples. The presence of the Cu2+/Cu+ pair at the surface of the catalysts is necessary to carry out the reaction and the catalysts containing higher amount of copper at the surface, resulted to be more active. The leaching of metals was less than 1%, which discards the contribution of the homogenous Fenton-like reaction and remarks the high stability of the metals into the mixed oxide network. The catalytic activity of LaCu0.8Mn0.2O3 was maintained after three cycles of reaction, which proves the stability and reusability of the catalyst.

Application of chemometrics to analysis of soil pollutants

This overview focuses on the application of chemometrics techniques for the investigation of soils contaminated by polycyclic aromatic hydrocarbons (PAHs) and metals because these two important and very diverse groups of pollutants are ubiquitous in soils. The salient features of various studies carried out in the micro- and recreational environments of humans, are highlighted in the context of the various multivariate statistical techniques available across discipline boundaries that have been effectively used in soil studies. Particular attention is paid to techniques employed in the geosciences that may be effectively utilized for environmental soil studies; classical multivariate approaches that may be used in isolation or as complementary methods to these are also discussed. Chemometrics techniques widely applied in atmospheric studies for identifying sources of pollutants or for determining the importance of contaminant source contributions to a particular site, have seen little use in soil studies, but may be effectively employed in such investigations. Suitable programs are also available for suggesting mitigating measures in cases of soil contamination, and these are also considered. Specific techniques reviewed include pattern recognition techniques such as Principal Components Analysis (PCA), Fuzzy Clustering (FC) and Cluster Analysis (CA); geostatistical tools include variograms, Geographical Information Systems (GIS), contour mapping and kriging; source identification and contribution estimation methods reviewed include Positive Matrix Factorisation (PMF), and Principal Component Analysis on Absolute Principal Component Scores (PCA/APCS). Mitigating measures to limit or eliminate pollutant sources may be suggested through the use of ranking analysis and multi criteria decision making methods (MCDM). These methods are mainly represented in this review by studies employing the Preference Ranking Organisation Method for Enrichment Evaluation (PROMETHEE) and its associated graphic output, Geometrical Analysis for Interactive Aid (GAIA).

Soil differentiation using fingerprint Fourier transform infrared spectroscopy, chemometrics and genetic algorithm-based feature selection

Elliott, G. N., Worgan, H., Broadhurst, D. I., Draper, J. H., Scullion, J. (2007). Soil differentiation using fingerprint Fourier transform infrared spectroscopy, chemometrics and genetic algorithm-based feature selection. Soil Biology & Biochemistry, 39 (11), 2888-2896. Sponsorship: BBSRC / NERC RAE2008