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1.
Caloptropis procera (Oshar) is a desert plant that did not receive much attention from the science community. The objective of this study was to investigate the elemental composition of the different parts of the plant using an X‐ray analytical microscope, to identify the elements naturally present in the plant and in the future detect the presence of any contaminants absorbed by the plants from the surrounding environment. Stalks, leaves and flowers from three Oshar plants were qualitatively and quantitatively analyzed. Leaves were scanned to establish the elemental spatial distribution within individual leaves. Subsequently, parts of the plants were dried, crushed and pulverized, then analyzed to determine elemental concentrations. The major elements present throughout the plant were Cl, K and Ca with varied concentrations. Other elements (Mg, Si, P, Fe, Sr, Mn and Br) are present in the leaf with various low concentrations of <5%. Major, minor and trace elements present in the various plant parts were determined. The outcome of this study will be used as a pilot for further investigations pertaining to the utilization of the Oshar plant for environmental cleaning purposes. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

2.
Direct analysis of essential oil has been performed for estimation of the elemental content in five different extracted essential oils from the leaves of different plants, namely, Mentha longifolia, Rosmarinus officinalis, Ocimum basilicum, Elletaria cardamomum, and Lavandula hybrida. A benchtop total reflection X-ray fluorescence spectrometer with a maximum power of 40 W was used for this purpose. Fourteen elements have been quantified in most of the extracted essential oil samples, and their limits of detection were determined. The detected elements are P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Br, Ni, and Hf. The validity of the present method was demonstrated using a standard reference material of organometallic oil sample. Two extraction methods of essential oils from leaves of the mentioned plants are evaluated, namely, classical hydro-distillation and microwave-assisted hydro-distillation. The quantitative elemental analysis of the extracted essential oils using the two extracted methods was studied and compared.  相似文献   

3.
4.
The number of studies dealing with nanoparticles (NPs) and plants has increased. They subsidize the advances of agriculture in the 21st century; however, so far, beneficial as well as detrimental results have been reported. In this context, analytical tools for monitoring macronutrients and micronutrients in plants exposed to NPs, with adequate performance and low cost, are required. This work assesses the use of energy-dispersive X-ray fluorescence (EDXRF) spectrometry for elemental content evaluation in NP-containing agricultural samples. For Phaseolus vulgaris (common bean) seedlings treated with ZnO NP, CuO NP, and Fe3O4 NP, the limits of detection (LODs) were 0.4 mg kg−1 for Zn and Cu and 0.6 mg kg−1 for Fe after dry-ashing digestion, thus being suitable for NP oxide monitoring in seed priming. For submicron suspension fertilizers, Mn, Cu, and Zn were quantified as thin films after sample dilution. The LODs for Mn, Cu, and Zn were 0.09, 0.1, and 0.08 mg L−1, respectively. Finally, for P. vulgaris plants exposed to 300-nm ZnO NP, we monitored P, S, K, Ca, and Zn directly in powdered leaves, whose LODs ranged from 1.3 to 27 mg kg−1. No critical spectral interference was observed, and notable repeatability and suitable trueness were found in the cases of studies. EDXRF revealed itself a simple, fast, and reliable alternative to evaluate the elemental content in suspensions or the uptake of NP by plants.  相似文献   

5.
应用原子吸收光谱法测定了两份耐盐性不同的野生披碱草种质材料在不同盐浓度胁迫条件下根组织和叶组织中的大量元素(Na,K,Ca,Mg)和微量元素(Cu,Fe,Mn,Zn)含量,并对野生披碱草种质材料矿质元素吸收和积累的选择性与耐盐性的关系进行了分析,结果表明:随着盐胁迫浓度的升高,野生披碱草种质材料叶和根组织中Na含量不断增加,耐盐材料HS叶组织中的Na含量显著低于敏盐材料LS(P<0.05);而K和Ca含量呈下降的趋势,在高浓度盐胁迫下,耐盐材料HS中两种元素的含量显著高于敏盐材料LS(P<0.05);微量元素Fe和Zn在野生披碱草材料根、叶组织中的含量升高,Cu在根组织中的含量没有变化,但是在叶组织中升高,而Mn在根、叶组织中的含量都呈下降的趋势,耐盐材料HS叶组织和根组织中Zn和Fe含量低于敏盐材料LS,Mn含量显著高于敏盐材料LS(P<0.05)。  相似文献   

6.
X-ray fluorescence (XRF) spectrometry is a nondestructive, rapid, simultaneous multi-elemental imaging methodology for plant materials. Its applications are broad and cover most of the elements with varying concentration below the parts per million (ppm). XRF is a well-established atomic spectrometric technique that is also being used as a field portable instrumentation. In recent decades, XRF has been considered a very versatile tool for plant nutrition diagnosis due to its fast and multi-elemental analytical imaging response directly from a solid sample. In this review, we have mainly focused on the recent developments and advancements in XRF spectrometry to analyze plant materials. We have also included the fundamental aspects and instrumentation for XRF spectrometry for its use in plants imaging. We have also covered the use of XRF for vegetal tissues and plant leaves. Mainly, we have briefly focused on some features of sampling procedures and calibration strategies regarding the use of XRF for plant tissues. Microchemical imaging applications by XRF, μ-XRF, μ-SRXRF, and TXRF have been covered for a wide variety of plant tissues such as leaves, roots, stems, and seeds.  相似文献   

7.
Abstract

The effects of earthworm activity on the concentration and isotopic composition of total sulfur in soils was investigated using batch experiments. Two ecologically different lumbricid species, the anecic Lumbricus terrestris and the endogeic Aporrectodea caliginosa, were used. The earthworms were fed birch leaves, beech leaves, cattle manure or mixed plant litter. All food sources differed isotopically (δ34S) from the soil (Parabraunerde). As a reference, one experiment was carried out without additional food.

The experimental results show, that both earthworm species influence the total S-content and the δ34S-values in the soil by digestion of the different food sources. The differences in the total S-content of the earthworm tissues and in the S-isotopic composition of the casts can be attributed to the ecological differences between the earthworm species.  相似文献   

8.
利用同步辐射X射线荧光 (SR XRF)定性和定量地分析了采自中国青岛海滨的 9种海藻 1 4个样品重元素的富集特性 ,发现不同种海藻重元素的富集特性有很大的差异。海蒿子对As和Sr,鸭毛藻对Br,海带对Ⅰ具有超富集能力。Mn/Fe峰强比的变化 ,是元素间拮抗的结果 ,与海水环境相关。测量了标样植物南极苔藓的检出限。定量地分析和比较了在青岛同一海滨分别于 1 985年和 1 999年采集的 5种海藻样品的XRF谱。1 999年采集的海藻的Fe ,Zn ,As,Br和Pb等元素含量明显上升 ,特别是海蒿子中的As和刺石松中的Pb分别增加了 1 55 %和 1 2 0 % ,结果说明了 1 4年来青岛海洋环境污染加重的趋势。  相似文献   

9.
It is widely accepted that tobacco smoke is the leading cause of lung cancer worldwide. The alpha radioactive content present in tobacco smoke and increasing number of lung cancer cases explain the importance of investigation. The use of different fertilizers may cause alteration in the metabolism of plants causing different response towards uptake of different element and radionuclides. In the present study, the estimation of alpha radioactivity induced by use of different fertilizers in tobacco leaves was made using solid state nuclear track detector (LR-115) to identify the relative presence of radionuclides in the plants. The radon exhalation rates from the tobacco plant were carried out to confirm the presence of radium or emission of radon from plant. The elemental analysis of tobacco plant by inductively coupled argon plasma atomic emission spectrometry provides a way to understand the difference occurred in metabolism caused by the use of fertilizers. The alpha track densities were found to vary with nature of fertilizers added to the soil and an increase was also observed with time. The radon mass exhalation rates in various tobacco plants were found to vary with type of fertilizers used.  相似文献   

10.
X-ray fluorescence analysis using synchrotron radiation is applied to determine the elemental composition in the leaves of Pentaphylloides fruticosa (L.) O.Schwarz (bush cinquefoil) and Lonicera caerulea subsp. altaica ((Pall.) Gladkova) (blue honeysuckle) growing in a geologically active area. It is found that in the studied period, the total content of microelements increases in the Pentaphylloides fruticosa leaves in the area of geological heterogeneity than that in the control one, and on the contrary, it decreases in Lonicera caerulea. The relationship between Fe/Mn, Ca/Sr, Cu/Zn, and K/Rb ratios and the geochemical and geophysical features of the environment and element accumulation by different types of plants is established. It is noted that two types of bushes under study react differently to changes in the geochemical and geophysical characteristics of the environment.  相似文献   

11.
In the present study, a combination of the stable carbon isotope ratio (13C/12C) with radiocarbon data (14C) allowed us to perform the aerosol source apportionment. Filter samples of PM1 were collected during the warm and cold periods in rural and urban sites in Lithuania. The 14C/12C ratio of total carbon (TC) was measured using the single stage accelerator mass spectrometer quantifying of fossil and non-fossil derived aerosol emissions. The δ13C value was measured using an elemental analyser interfaced with an isotope ratio mass spectrometer. We have found that the highest fraction of contemporary carbon (fc?=?0.82) was measured during a warm period in a rural location. A higher fraction of fossil fuel-derived carbon was observed for air masses transported from highly industrialized Western European regions during both seasons. Isotope mass balance calculations revealed that the traffic emissions composed 15 and 25?% in rural and urban sites, respectively, and did not change during either season. Input from coal-derived aerosol particles was estimated to be 15?% at an urban site during the cold period. The combination of the stable carbon isotope ratio with the radiocarbon data allowed us to distinguish coal, liquid fossil fuel combustion, and non-fossil derived aerosol particle emissions.  相似文献   

12.
High-resolution imaging secondary ion mass spectrometry (HRI-SIMS) in combination with inductively coupled plasma mass spectrometry (ICP-MS) were utilised to determine specific sites of chromium concentration in tomato plant tissues (roots, stems and leaves). The tissues were obtained from plants grown for 2 months in hydroponic conditions with Cr added in a form chromium salt (CrCl3·6H2O) to concentrations of 25 and 50 mg/L. The chemical fixation procedure used permit to localize only insoluble or strongly bound Cr components in tomato plant tissue. In this work no quantitative SIMS analysis was made. HRI-SIMS analysis revealed that the transport of chromium is restricted to the vascular system of roots, stems and leaves. No Cr was detected in epidermis, palisade parenchyma and spongy parenchyma cells of the leaves. The SIMS-300 spectra obtained from the tissues confirm the HRI-SIMS observations. The roots, and especially walls of xylem vessels, were determined as the principal site of chromium accumulation in tomato plants.  相似文献   

13.
杨红龙  李磊  杨溯  卢超  陈星登  刘爱明 《光子学报》2014,41(12):1427-1434
气溶胶是影响气候变化和空气污染的重要因子.在深圳地区展开气溶胶观测实验,可以获得可靠的光学物理特征,进而有助于准确评估气溶胶在新型超极城市区域的气像和环境效应.本文利用2010年12月至2011年8月太阳光度计、黑碳和浊度计等气溶胶观测资料,分析了新型超级城市深圳地区的气溶胶物理光学特性.深圳地区气溶胶呈明显季节变化,冬、春季由于城市污染性气溶胶的影响,气溶胶光学厚度和Angstrom波长指数都较大,夏季受海盐气溶胶的影响,光学厚度较小,Angstrom波长指数也较小.光学厚度与Angstrom 波长指数对比表明城市综合性污染是引起深圳气溶胶高光学厚度的主要原因.深圳地区气溶胶的散射系数、吸收系数的平均值(标准偏差)分别为178.7×10-6 m-1(126.6×10-6 m-1)和32.5×10-6 m-1(18.1×10-6 m-1),均低于珠三角腹地多年观测平均值的二分之一和国内其他大型城市观测值.而单次散射反照率为0.81,与珠三角其他地区得到的结果接近.此外,气溶胶吸收、散射和单次散射反照率呈明显日变化,可能主要受大气边界层变化的影响.  相似文献   

14.
The content of such typical ecologically hazardous chemical elements as Pb, Ni, Cu, Sr, and Zn in soil and plant ash from the vicinity of an industrial center is measured. Since the main sources of these elements are smoke aerosols of industrial origin, the dependence of the concentrations of these elements on the distance from highly profuse, continually operating sources of emission is measured to a distance of ∼10 km. It is shown that the laws governing the variation of the concentration of different chemical elements in soil with the distance from the source of emission into the atmosphere are determined by the conditions of their gravity settling with consideration of the electrical interaction of the aerosol with the ground electric field and that the laws in plant ash are determined by the accumulation of highly dispersed, charged aerosol on the surface of plant leaves polarized in the ground electric field. Zh. Tekh. Fiz. 68, 20–24 (March 1998)  相似文献   

15.
A portable energy dispersive X-ray fluorescence (XRF) spectrometer furnished with an Rh X-ray tube was evaluated for the determination of macronutrients and micronutrients in soybean leaves (Glycine max L.). XRF instrumental parameters were optimized in a univariate way, and emission intensities were measured for 60 s and under vacuum for macronutrients, and during 180 s, under air, and 305 μm Al/25.4 μm Ti filter, for micronutrients. Fresh and dried leaves were irradiated, and it was possible to identify P, K, Ca, S, Mn, Fe, Cu, and Zn Kα emission lines. For comparative purpose, the samples were also microwave assisted, digested and analyzed by inductively coupled plasma optical emission spectrometry. In general, linear correlations between K, Ca, Mn, Fe, Cu, and Zn concentrations in the tested samples and the corresponding portable XRF (pXRF) intensities were obtained. The linear correlation coefficients (R2) ranged from 0.42 to 0.86. In addition, the detection limits were suitable for plant nutrient diagnosis. It is demonstrated that pXRF is a simple and powerful tool for analysis of plant materials.  相似文献   

16.
近年来风沙灾害已成为全球性环境问题。沙生植物具有独特的生态生物学特性,在改善生态环境等方面起着十分重要的作用。采用ICP-AES法测定分析了世界范围内仅集中分布于内蒙古西鄂尔多斯草原化荒漠区的国家二级濒危保护物种——全株四合木中的金属元素,并与其他沙生植物金属含量进行了比较。结果表明,常量元素Ca,K,Mg,Na,Al及植物生命活动所必需的微量元素Fe,Mn,Cu,Zn在全株四合木中表现为不同的含量顺序,主根和老枝:Ca>Na>Mg>Al>K>Fe>Cu>Mn>Zn,嫩枝和叶:Ca>Na>Mg>Al>K>Fe>Mn>Cu>Zn,须根K>Ca>Na>Mg>Al>Fe>Cu>Mn>Zn,且Mn,Zn元素的含量低于陆生高等植物的平均含量。该方法的加标回收率为94.98%~120.0%,RSD<3.5%,具有良好的准确度和精密度。此测定结果可作为濒危植物和野生植物资源的保护与合理开发利用的参考。  相似文献   

17.
内蒙古地区沙生植物饲用养分含量分析研究   总被引:1,自引:0,他引:1  
利用化学和仪器方法,测定了内蒙古地区七种沙生植物叶、茎、株作为饲养成分的含量(干物质百分率):钙0.73~3.89,磷0.043~0.34,硒0.026~2.8,粗蛋白质3.38~13.92,粗脂肪3.97~15.03,总糖14.89~35.78,灰分0.61~14.33,中性洗涤纤维26.66~79.72,酸性洗涤纤维27.03~69.01,七种沙生植物叶、茎氨基酸总含量变动范围为2.30%~11.26%。除沙枣外,其余六种沙生植物叶、茎钙/磷均高于苜蓿叶粉和茎粉;硒含量均比植物中一般硒含量高;粗蛋白质达到了优质禾谷类粮食蛋白含量的水平;叶、茎、全株粗脂肪含量均高于玉米秸秆和小麦秸秆;叶中总糖含量均大于其茎和株;灰分含量高;叶中性洗涤纤维均低于苜蓿叶粉,茎中性纤维均高于苜蓿叶粉;除梭梭外,其余植物茎酸性洗涤纤维均高于苜蓿茎粉。实验表明,七种沙生植物适宜于家畜饲养的要求,是沙区发展草地畜牧业优质的饲草资源。  相似文献   

18.
Synchrotron radiation X-ray fluorescence analysis is used to determine for the first time the absolute content and biological accumulation coefficients for a set of 21 chemical elements (K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Nb, Y, Mo, and Pb) in the fruits, leaves, bark, roots, and root nodules of the sea buckthorn (Hippophae rhamnoides L. ssp. mongolica Rousi). It is found that all sea buckthorn tissues accumulate Ti, Nb, Cr, and Zr more intensively than the global average for terrestrial phytomass. On the other hand, none of the examined parts of the sea buckthorn plants accumulated the toxic elements Pb and As.  相似文献   

19.
New analyses of a series of very rare silverpoint drawings that were executed by Rembrandt Harmensz. van Rijn (1606–1669) which are kept today in the Kupferstichkabinett (Museum of Prints and Drawings) of the State Museums of Berlin are reported here. Analysis of these drawings requires particular attention because the study has to be fully non-destructive and extremely sensitive. The metal alloy on the paper does not exceed some hundreds of μg/cm2. Therefore, synchrotron radiation induced X-ray fluorescence (SR-XRF) is – together with external micro-proton-induced X-ray emission – the only well-suited method for the analyses of metalpoint drawings. In some primary work, about 25 German and Flemish metalpoint drawings were investigated using spatially resolved SR-XRF analysis at the BAMline at BESSY. This study enlarges the existing French–German database of metalpoint drawings dating from the 15th and 16th centuries, as these Rembrandt drawings originate from the 17th century where this graphical technique was even rarer and already obsolete. It also illustrates how SR-XRF analysis can reinforce art historical assumptions on the dating of drawings and their connection. PACS 89.90.+n; 81.70.Jb; 81.05.Bx  相似文献   

20.
Understanding mechanisms that control plant root metal assimilation in soil is critical to the sustainable management of metal‐contaminated land. With the assistance of the synchrotron X‐ray fluorescence technique, this study investigated possible mechanisms that control the localization of Fe, Cu, Mn, Pb and Zn in the root tissues of Typha latifolia L. collected from a contaminated wetland. Metal localizations especially in the case of Fe and Pb in the dermal tissue and the vascular bundles were different. Cluster analysis was performed to divide the dermal tissue into iron‐plaque‐enriched dermal tissue and regular dermal tissue based on the spatial distribution of Pb and Fe. Factor analysis showed that Cu and Zn were closely correlated to each other in the dermal tissues. The association of Cu, Zn and Mn with Fe was strong in both regular dermal tissue and iron‐plaque‐enriched dermal tissue, while significant (p < 0.05) correlation of Fe with Pb was only observed in tissues enriched with iron plaque. In the vascular bundles, Zn, Mn and Cu showed strong association, suggesting that the localization of these three elements was controlled by a similar mechanism. Iron plaque in the peripheral dermal tissues acted as a barrier for Pb and a buffer for Zn, Cu and Mn. The Casparian strip regulated the transportation of metals from dermal tissues to the vascular bundles. The results suggested that the mechanisms controlling metal localization in root tissues varied with both tissue types and metals.  相似文献   

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