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21.
小功率空气冷却ICP-AES 研究I——小功率空气冷却ICP的特性 总被引:1,自引:1,他引:1
本文用顺序等离子体光谱仪研究了27.12MHz他激式R.F.发生器点燃的小功率空气冷却ICP的特性。测量并比较了二十个元素五十七条谱线在空气冷却和氩冷却两种ICP中的检测限。 相似文献
22.
The new electrolytic dissolution in batch of aluminum alloys samples as grains or turns and the determination of Fe, Cu, Mn, Mg, Cr, Ni, Zn, Pb and Ti by ICP OES was investigated. In on-line electrodissolution procedures described in the literature, samples were restricted to be in the form of solid blocks or plates with one polished flat face. Here, the sample was loaded in the barrel of a modified disposable syringe (the anodic semi-cell) and pressed with a modified plunger fitted with a platinum disk to establish electrical contact with the analyte. This arrangement was introduced in a beaker containing the electrolyte (1 mol L−1 HNO3) and a platinum wire as the cathode. The resulting solution from electrodissolution (0.6 A) was used for the ICP OES determinations. The influence of the aluminum concentration increase on the determination of the elements was evaluated. Electrodissolution of certified reference materials and commercial samples revealed relative errors lower than 10% for the elements Fe, Cu, Mg, Ni, Cr, Zn and Ti (when their content is above 0.1%). Higher inaccuracies (>10%) were observed for Mn and for Fe in B.C.S. 268/1 reference material certified. The proposed method presented a relative standard deviations (R.S.D.) lower or circa 10% to all of the elements (except Pb). In comparison with traditional acid dissolution, the proposed electrodissolution method is relatively fast (about 30 min), it is clean (there is no projection of solution) and simple (heating and fumes exhaust system were not necessaries). 相似文献
23.
《Analytical letters》2012,45(9):1615-1622
Abstract A simple and rapid method for the simultaneous determination of seven trace elements in biodiesel by axial and radial view Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) is proposed, in which the sample is emulsified with Triton X-100 and water, and in which yttrium is employed as an internal standard. The better obtained quantification limits (10 s) were by axial view, 0.165, 0.099, 0.033, 0.007, 0.016, 0.132, 0.660 µg g?1 for Ca, Cu, Fe, Mg, Mn, Na, and P, respectively, based on a sample mass of 1.0 g diluted to a final mass of 10 g in the analytical solution. Calibration was carried out with aqueous standards, thus avoiding the use of frequently instable organic standards. Elemental recoveries were in the range of 90 to 109% for all seven analytes studied, and also the precision of the method was satisfactory (RSD < 8%). 相似文献
24.
《Arabian Journal of Chemistry》2021,14(12):103451
Tinnevelly senna leaves are being applied to cure many diseases especially in developing countries and sub-Saharan region due to many bioactive compounds such as sennosides, phenols, and flavonoids. The conventional methods to isolate and analyze plant extracts biomolecules are not very effective as well cost effective as they require hazardous chemical solvents and reagents, which are time-consuming processes. The major objective of the present study is to investigate the feasibility of the Laser induced breakdown spectroscopy (LIBS) technique for rapid, eco-friendly, and multi-elemental analysis of Senna leaves extracts and study their antibacterial and anticancer potentials. The elegant LIBS technique was applied as a qualitative and quantitative method for Senna leaves sample’s elemental analysis and their biological activities were measured by evaluating anti-cancer and anti-bacterial analysis. The quantitative analysis of Senna leaves extracts was done using the calibration-free laser-induced breakdown spectroscopy (CF-LIBS) algorithm showing their appreciable content of several nutrient elements, and the obtained results were in close conformity with these achieved by using the standard analytical ICP OES technique. We studied the bactericidal efficacy of the Senna leaves extract against Staphylococcus aureus (S. aureus) by AWD assays and morphogenesis by scanning electron microscopy (SEM) and the anticancer activity was also investigated where different concentrations of Senna leaves extract were tested on cancer cells (HCT-116 and HeLa) and normal cells (HEK-293) using the cell metabolic activity MTT assay and Propidium iodide (PI) staining. We have also calculated the inhibitory concentration (IC50) value for the various extracts concentrations (25 µg/ml, 50 µg/ml, 100 µg/ml, 150 µg/ml, 200 µg/ml, and 225 µg/ml). We have found that IC50 value for HCT-116 cells were 13.5 µg/ml, 17.5 µg/ml, 21.5 µg/ml, 22.5 µg/ml, 26 µg/ml and 33.5 µg/ml and for HeLa cells 15.25 µg/ml, 21.25 µg/ml, 23.5 µg/ml, 262.5 µg/ml, 36.25 µg/ml, and 39.50 µg/ml. The bactericidal efficacy of the Senna leaves extract showed significant inhibition against Gram-positive bacterium. Both MTT and PI analysis showed that Senna leaves extract induced profound inhibition on HCT-116 growth and proliferation. Additionally, Senna leaves extract did not exert an inhibitory influence on normal (HEK-293), which is non-cancerous cells. We suggest that the extract specifically targets the cancerous cells, which could be highly beneficial for the development of future safe anticancer and antibacterial drugs using these extracts. 相似文献
25.
《Current Applied Physics》2015,15(9):1036-1041
Spatial distributions of the effective electron temperature (Teff) and plasma potential were studied from the measurement of an electron energy probability function in a side type ferrite-core inductively coupled plasma with an argon–helium mixture. As the helium gas was diluted at the fixed total gas pressure of 5 mTorr in an argon discharge, the distribution of the plasma density and plasma potential changed from a concave to a flat profile, and finally became a convex profile, while all spatial profiles of Teff were hollow shapes with helium dilution in the argon discharge. This evolution of the plasma potential with helium gas could be explained by the increased energy relaxation length (λε), indicating the transition of electron kinetics from local to non-local kinetics. 相似文献
26.
27.
基于包层模的光纤布拉格光栅折射率传感特性 总被引:5,自引:0,他引:5
提出了基于光纤布拉格光栅(FBG)包层模式的折射率传感方案。实验中,利用不同浓度的丙三醇水溶液作为外界折射率传感溶液,采用氢氟酸溶液化学腐蚀的方法来减小光纤包层的直径以增大包层模式对外界折射率的敏感度,研究了腐蚀后光纤布拉格光栅包层模式的耦合波长对外部折射率的变化关系。实验结果表明在1.3300~1.4584的折射率范围内,包层模式耦合波长随外界折射率增大而增大,在接近光纤包层折射率处具有很高的折射率灵敏度,最大达到了172 nm/riu(refractive index unit)。而且,包层模谐振的光谱半峰全宽(约0.07 nm)仅为布拉格纤芯模谐振光谱半峰全宽的1/4,能够获得更好的传感精度。 相似文献
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29.
30.
研究了CID-IP-AES用于测定高纯物质的分析性能。以高纯LiOH为对象,研究了低浓度范围内分析线的选择,标准曲线的特性,探讨了直接用于高纯物质分析的检测能力及可行性。 相似文献