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1.
Abstract

The applicability of radionuclides for the analysis of the physico-chemical state and behaviour of trace elements in natural waters was studied with six radionuclides in two typical river water Adsorption, ion exchange filtration, centrifugation, dialysis and electrophoresis of Ba, Fe, Sc, Zn, Mn and Cr in river water were investigated by a radiotracer method and by instrumental activation analysis. God correspondence between the results by both methods was obtained only when the radionuclide and corresponding natural element existed predominantly as simple cations at the beginning of experiment. In the other cases, considerable differences in the behaviour of the radiotracer and its stable counterpart were found even after 35 days of equilibration. Very slow isotope exchange was observed particularly with colloidal or organically complexed forms of the natural trace elements. The analysis of the state of trace elements may be further complicated by a change of this state during the time necessary for isotope equilibration. Thus, the radio-tracer method has serious limitations in this field.  相似文献   

2.
Abstract

Aim of this study was to evaluate polyphenols and major and trace elements of Cladanthus arabicus and Bubonium imbricatum, along with their in vitro antibacterial activity against six multidrug resistant Enterobacteriaceae (Escherichia coli S33/16, E. coli S34/16, Proteus mirabilis S32/16, Klebsiella pneumoniae S12/16, Enterobacter cloacae S5/16, and Salmonella sp S12/14). UV spectrophotometry, ultra-high-performance liquid chromatography coupled to mass spectrometry and inductively coupled plasma mass spectrometry were used to evaluate total polyphenol content, quali-quantitative profile of single polyphenols and inorganic elements of the extract. The antibacterial activity was investigated by standard methods. Twelve polyphenols were identified in both plants and these were more concentrated in B. imbricatum than C. arabicus extracts. High levels of minerals, essential trace elements and tolerable levels of heavy metals (Cd, As and Pb) were found. Furthermore, the extracts showed also a strong in vitro antibacterial activity, particularly versus E. coli S33/16 (MIC, 0.125?mg ml?1).  相似文献   

3.
Methods are described for the determination of trace and ultra trace amounts of Cd, Co, Cr, Cu, Fe, Mn, Ni and Pb in natural waters, alkali and alkaline earth salts. Separation and preconcentration of trace metals is achieved by a column solid phase extraction procedure using silica gel modified with derivatives of dithiocarbamates — Na-DDTC (sodium diethyldithio-carbamate and HMDTC (ammonium hexamethylene-dithiocarbamate) as column packing material. The influence of the sorbent preparation procedure on the degree of sorption of the trace analytes is examined for different pH values of the sample solution. Isobutylmethyl ketone (IBMK) is proposed as an effective eluent for quantitative elution of retained metal ions. Optimal instrumental parameters for ETAAS determination of preconcentrated elements in organic eluate are presented. Practical application of sorbents in analysis of natural waters and alkali and alkaline earth salts is demonstrated. Proposed preconcentration procedure combined with ETAAS determination of trace analytes allows the determination of 0.04 g l–1 Cd, 0.1 g l–1 Cr, Cu, and Mn and 0.3 g l–1 Co, Fe, Ni and Pb in natural waters and 1.10–7% Cd, 3.10–7% Cr and Mn, 7.10–7% Co, Ni and Pb and 2.10–6% Cu and Fe in alkali and alkaline earth salts.  相似文献   

4.
甲状腺功能亢进症患者血清铜、锌、铁、钙、镁的研究   总被引:5,自引:0,他引:5  
为研究甲状腺功能亢进症患者血清中 5种微量元素的变化及其与甲状腺功能激素间的关系 ,用分光光度分析和放射免疫分析分别检测了 1 2 2例甲状腺疾病患者血清中微量元素Cu、Zn、Fe、Ca、Mg含量和血清中甲状腺激素 (T3、T4 )水平。结果表明 ,甲状腺功能亢进症患者血清中Cu、Ca元素水平明显高于对照组 (P <0 0 1 ) ,Zn元素水平明显低于对照组 (P <0 0 0 1 ) ,Fe、Mg元素两组比较无统计学意义 ;血清Cu与T3、T4 浓度呈现一定程度的正相关 ,提示微量元素在甲状腺激素的合成、代谢和生物作用中可能有重要意义 ,甲状腺功能亢进症患者过多释放甲状腺素导致血清中元素的异常变化 ,此变化既能反映病人机体代谢紊乱程度 ,同时也可作为病情控制的参考指标。  相似文献   

5.
刘鹏宇 《分析试验室》2005,24(12):72-75
针对稀土金属中难熔金属杂质元素Ta、Mo、W、Ti、Nb在HCl或HNO3中不易溶解的性质,本文在前人工作基础上,采用HF络合-ICP-MS结合的方法,有效地将上述元素溶解在溶液中,并利用ICP-MS高灵敏度和多元素同时测定的优势,成功建立了稀土金属中难熔金属杂质元素Ta、Mo、W、Ti、Nb的测定方法。其操作过程较传统化学方法简便,灵敏度也更高。本文分析了氢氟酸的络合过程,试验了稀土氟化物沉淀对被测元素的吸附作用和内标法的校正作用。方法检出限在0.3~1.5ng/mL,测定下限0.0005%~0.0010%,回收率在89.2%~118.9%,相对标准偏差为4.6%~9.7%。  相似文献   

6.
东莞市儿童血清中5种微量元素及钙含量的分析研究   总被引:4,自引:0,他引:4  
测定了东莞市 1 3 89名儿童血清中锌 (Zn)、铁 (Fe)、铜 (Cu)、锰 (Mn)、铅 (Pb)及钙 (Ca)含量。结果分别为Zn (0 973± 0 2 3 8) μg/mL、Fe (1 1 0 1± 0 2 41 ) μg/mL、Cu (0 90 5±0 2 1 3 ) μg/mL、Mn (0 0 3 9± 0 0 2 0 ) μg/mL、Pb (0 0 5 3± 0 0 1 5 ) μg/mL及Ca (85 2 5 2± 1 4 795 )μg/mL,男女间没有显著差异。  相似文献   

7.
不同产地麦冬中锌、铜、锰、铁的比较研究   总被引:9,自引:0,他引:9  
采用火焰原子吸收法测定了不同产地麦冬中锌、铜、锰和铁的含量,比较了不同产地麦冬中w(Zn)/w(Cu)比值。结果表明,湖北麦冬的w(Zn)/w(Cu)比值最高,浙江麦冬和四川麦冬的w(Zn)/w(Cu)比值接近,从微量元素的角度来看,湖北麦冬的品质优于其它产地。  相似文献   

8.
《Analytical letters》2012,45(2):283-302
Abstract

A method is described for the reliable determination of copper, lead, cadmium and zinc in natural waters by anodic stripping potentiometry with the use of a novel combined electrode. The method involves two stripping cycles during which copper is initially determined on its own, followed by simultaneous determination of lead, cadmium and zinc after addition of gallium (III) ions. The optimum conditions include 0.01 M HCl as supporting electrolyte, 10 mg/L Hg (II) as chemical oxidant; Edep(Cu) -700 mV vs Ag/AgCl; Edep(Pb,Cd,Zn) -1200 mV vs Ag/AgCl; tdep 10s; 150 μg/L Ga (III); sample rotation rate 5 and rest period 30s. Under these conditions, as low as 0.06 μg/L Cu (0.7% RSD); 0.2 μg/L Pb (13% RSD); 0.04 μg/L Cd (7.8% RSD) and 0.06 μg/L Zn (5.5% RSD) can be determined reliably. A linear concentration range of 0–110 μg/L was obtained for the four metals. The successful application of the method to reference fresh water, creek water and tap water is demonstrated.  相似文献   

9.
In the present study, three-step Community Bureau of Reference sequential extraction scheme (BCR-SES) and single extraction methods were performed to assess the mobility and availability of heavy metals (Cd, Cu, Pb, Fe and Zn) in an agricultural soil before and after amendment with poultry waste (PW).The PW samples were collected from poultry farms, situated in Hyderabad Sindh, Pakistan. The extractable heavy metals were measured by flame and electrothermal atomic absorption spectrometry. The validation of the method was carried out by analysis of a certified reference material of soil amended with sewage sludge (BCR-483). The single extractions using calcium chloride and EDTA, separately, while BCR-SESs were developed to evaluate the available heavy metals to plants and their environmental accessibility for control soil (CS), PW and soil amended with PW (SPW).The pH of the PW and SPW were found to be < 6.0, which may enhance the leaching of heavy metals to agricultural soil. The results from the partitioning study indicated that easily mobilised forms (acid exchangeable) of Cd were higher than other heavy metals. The oxidisable fractions of all heavy metals were dominant in PW and SPW as compared to found in CS samples. The EDTA- and CaCl2-extractable heavy metals correspond to 5.0 to 10 and 0.5 to 3.0%, respectively of total contents in all three solid samples. Contamination factors revealed that the retention of Pb and Zn were higher compared with Cu, Cd and Fe in CS, PW and SPW samples.  相似文献   

10.
原子吸收和原子荧光光谱法测定茶园土壤中的微量元素   总被引:1,自引:0,他引:1  
采用微波消解-火焰原子吸收和原子荧光光谱法同时测定了贵州梵净山茶园土壤中14种微量元素含量,方法简单、准确、迅速,有助于全面、迅速地了解茶园土壤中微量元素的含量,对于特色茶叶品质鉴定和指导合理科学栽培茶树等方面有重要意义.  相似文献   

11.
慢性肺心病患者血清Cu,Zn及Cu/Zn比值的分析研究   总被引:1,自引:1,他引:1  
分析了65例慢性肺心病患者血清Cu,Zn的含量及Cu/Zn比值,并与健康对照组比较。结果显示,慢性肺心病患者组血清Zn的含量与健康对照组比较有高度显著性差异(P<0.01),Cu的含是有显著性差异(P<0.05),Cu/Zn比值有显著性差异(P<0.05)。提示慢性肺心病与微量元素Cu、Zn元素的含量变化有一定的关系,为研究元素医学与治疗慢性肺心病提供了必要的依据。  相似文献   

12.
Inductively coupled plasma mass spectrometry (ICP-MS) has been used to measure the concentration of trace and rare earth elements (REEs) in soils. Geochemical certified reference materials such as JLk-1, JB-1, and JB-3 were used for the validation of the analytical method. The measured values were in good agreement with the certified values for all the elements and were within 10% analytical error. Beach placer deposits of soils mainly from Odisha, on the east coast of India, have been selected to study selected trace and rare earth elements (REEs), to estimate enrichment factor (EF) and geoaccumulation index (Igeo) in the natural environment. Enrichment factor (EF) and geoaccumulation index (Igeo) results showed that Cr, Mn, Fe, Co, Zn, Y, Zr, Cd and U were significantly enriched, and Th was extremely enriched. The total content of REEs (ƩREEs) ranged from 101.3 to 12,911.3 µg g−1, with an average 2431.1 µg g−1 which was higher than the average crustal value of ΣREEs. A high concentration of Th and light REEs were strongly correlated, which confirmed soil enrichment with monazite minerals. High ratios of light REEs (LREEs)/heavy REEs (HREEs) with a strong negative Eu anomaly revealed a felsic origin. The comparison of the chondrite normalized REE patterns of soil with hinterland rocks such as granite, charnockite, khondalite and migmatite suggested that enhancement of trace and REEs are of natural origin.  相似文献   

13.
Children growth and development may be affected by metal exposure. The objective of the present study was to investigate the interactive effects of age and gender on children hair toxic metal levels in urban environment of two Russian cities. A total of 2021 children living in Moscow and Novosibirsk aged 1–18 years old were examined. Hair Al, As, Cd, Hg, Ni, Pb and Sn levels were assessed using inductively-coupled plasma mass-spectrometry in dynamic reaction cell mode. Children from Novosibirsk were characterised by higher hair Al (37%), As (385%), Cd (127%), Hg (11%), Ni (23%), Pb (72%) and Sn (25%) in comparison to Moscow values. In the general cohort, boys had higher Al (13%), As (51%), Cd (65%), Pb (63%) and Sn (18%) levels, whereas hair Ni was higher in girls (17%). Further analysis demonstrated age-specific gender differences. In particular, only hair Ni and Cd levels were higher in male toddlers and pre-schoolers from Novosibirsk as compared to females. No gender difference was detected in Moscow. Maximal gender differences in hair metal levels were detected in adolescents for both locations. International Union of Pure and Applied Chemistry (IUPAC) reference values for all groups were also calculated. The overall reference limits for the studied children population were Al (1.335–3.340 µg/g), As (0.021–0.384 µg/g), Cd (0.000–1.389 µg/g), Hg (0.024–0.722 µg/g), Ni (0.076–0.701 µg/g), Pb (0.050–1.490 µg/g) and Sn (0.070–1.026 µg/g). Two-way ANOVA demonstrated significant effects of age, gender and age*gender interaction on hair metals in both cities. At the same time, the age-specific changes in hair metal content were more expressed in children from Novosibirsk, being exposed to higher metal pollution. The obtained data demonstrate that age, gender as well as the particular rate of pollution in each location should be taken into account during interpretation of hair test results.  相似文献   

14.
The concentrations of heavy metals in the soil, mushroom and plant samples collected from Tokat, Turkey have been determined by flame and graphite furnace atomic absorption spectrometry after dry ashing, wet ashing and microwave digestion. The study of sample preparation procedures showed that the microwave digestion method was the best. Good accuracy was assured by the analysis of standard reference materials. The relative standard deviations for all measured metal concentrations were lower than 10%. In all cases, quantitative analytical recoveries ranging from 95 to 103% were obtained. Metal accumulation factors were calculated for mushroom and plant samples. High ratio of plants to soil cadmium, zinc and copper concentrations indicate that these elements are accumulated by mushrooms. Results obtained are in agreement with data reported in the literature.  相似文献   

15.
A quick sample preparation method was used for the determination of sulphur and trace metals in oil and oily products by the ICP with a minitorch. Stable aqueous emulsions of oils and oil products were made by using two kinds of emulsifiers (one with low sulphur content, the other sulfonated). Aqueous standard solutions can be used for the preparation of calibration solutions. The contents of S, Al, Cr, Cu, Fe, Mg, Ni and Pb in aqueous emulsions were determined and the results were in good agreement with the composition of oil standard solutions used for control analysis procedure.  相似文献   

16.
采用粉末压片法制样,使用ZSX PrimusⅡ型X射线荧光光谱仪,对土壤样品中与生命健康和环境污染有直接影响的重金属元素Cu、Pb、Zn、As、Sb、Co、Cr、Ni进行同时测定.选用土壤国家标准物质、以国家标准物质为基体自制校准物质绘制标准曲线,解决了相关标准不足的问题,拓宽了元素测定范围(10~20 000μg/g),重点探讨了As、Sb的测量条件.虽然As、Sb的检出限和准确测定下限较高,但对于土壤质量的评价有重要的参考意义.方法快速、简便、准确.  相似文献   

17.
为测定和分析精神发育迟滞儿童头发微量元素营养状态,选择来自某特殊学校学生(IQ均低于70)210例发样为观察组,采用原子吸收分光光度法测定发样中锌、铁、铜、钙、锰、铅、镁和铬含量.结果表明,本组210例精神发育迟滞儿童的发铅和发镁低于正常对照组,具有统计学意义.发锌稍高于对照组但无统计学意义,其它几种元素含量基本相似.可见特殊学校精神发育迟滞儿童的发铅和发镁比正常儿童低,其意义值得进一步分析.  相似文献   

18.
黄芪及其水煎液中Cu、Mn、Zn、Fe、Se的测定和浸出率研究   总被引:2,自引:0,他引:2  
用原子吸收法对黄芪及其水煎液中的Cu、Mn、Zn、Fe进行了测定 ,用紫外分光光度法测定了其中的Se ,从而得出各元素的浸出率。结果表明五种元素的浸出率为 :Cu >Zn >Mn >Se >Fe。  相似文献   

19.
(1) Background: Dyes play an important role in food, medicine, textile, and other industries, which make human life more colorful. With the increasing demand for food safety, the development of natural dyes becomes more and more attractive. (2) Methods: The literature was searched using the electronic databases PubMed, Web of Science, and SciFinder and this scoping review was carried out following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). (3) Results: 248 articles were included in this review. This review summarizes the research progress on natural dyes in the last ten years. According to structural features, natural dyes mainly include carotenoids, polyphenols, porphyrins, and alkaloids, and some of the newest dyes are summarized. Some pharmacological activities of carotenoids, anthocyanin, curcumin, and betalains in the last 10 years are summarized, and the biological effects of dyes regarding illumination conditions. The disadvantages of natural dyes, including sources, cost, stability, and poor bioavailability, limit their application. Here, some feasible strategies (potential resources, biotechnology, new extraction and separation strategies, strategies for improving stability) are described, which will contribute to the development and utilization of natural dyes. (4) Conclusion: Natural dyes show health benefits and potential in food additives. However, it is necessary for natural dyes to pass toxicity tests and quality tests and receive many regulatory approvals before their final entry into the market as food colorants or as drugs.  相似文献   

20.
The geminal organodimetallic complexes [({Ph2P(NSiMe3)}2C)2M4], where M4=Na4, 3; Li2Na2, 4; LiNa3, 5; Li2K2, 6; Na2K2, 7, and Na3K, 8, have been prepared through a variety of methods including direct or sequential deprotonation of the neutral ligand with strong bases (tBuLi, nBuNa, (Me3Si)2NNa, PhCH2K or (Me3Si)2NK), transmetalation of the homometallic derivatives (M4=Li4, 2 or Na4, 3) with tBuONa or tBuOK, and by cation exchange upon mixing the homometallic complexes in an arene solution. Complexes 3-8 have been characterized by single-crystal X-ray diffraction and are found to form a homologous series of dimeric structures in the solid-state, in accord with the previously reported structure of 2. Each complex is composed of a plane of four metals, M4, in which the ligands adopt capping positions to form distorted M4C2 octahedral cores. The metals in homometallic complexes 2 and 3 define an approximate square, whereas the heterometallic derivatives 4-8 have distinctly rhombic arrangements. The lighter metals in 4-8 interact strongly with the carbanions and the heavier metals are pushed towards the periphery of the structures. 1H, 13C, 7Li, 31P, and 29Si multinuclear NMR spectroscopic studies, cryoscopic measurements, and electrospray ionization-mass spectroscopic studies are consistent with the dimers being retained in solution. Dynamic solution behavior was discovered for Li2Na2 complex 4, in which all five possible tetrametallic derivatives Li4, Li3Na, Li2Na2, LiNa3 and Na4 coexist. Density functional theory (DFT) and natural bond order (NBO) calculations in association with natural population analyses (NPA) reveal significant differences in the electronic structures of the variously metalated dianions. The smaller cations are more effective in localizing the double negative charge on the carbanion (in the form of two lone pairs), leading to differences in the distribution of the electron density within the ligand backbones. In turn, a complex interplay of hyperconjugation, electrostatics and metal-ligand interactions is found to control the resulting electronic structures of the geminal organodimetallic complexes.  相似文献   

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