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World Journal of Nuclear Science and Technology 2024年第2期14卷 97-106页

作者： Alassane Traore Anna Ndiaye Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Département de Chimie Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Tandetron Laboratory IBA Group iThemba LABS Cape Town South Africa Africa Rice Center St. Louis Senegal

Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species.

关键词： PIXE 2D Mapping Rice Concentration elemental analysis

elemental analysis of some Egyptian ores and industrial iron samples by neutron activation analysis

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Journal of Environmental Sciences 2001年第1期13卷 115-118页

作者： A.Srror N.Abdel Basset A.S.Abdel Haleem A.M.Hassan Nuclear Physics Lab. Physics DepartmentFaculty of GirlsAin Shams UniversityCairoEgypt Environmental Radioative Pollution Department Hot Laboratories CentreAEACairoEgypt

elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. Five samples from each kind were irradiated for a 48 hours at a thermal neutron flux of 4×10 12 n/(cm 2.s) in the first Egyptian research reactor ET RR 1. Also the Pneumatic irradiation Rabbit system (PIRS) attached to the reactor in Inshass, was used to measure the elements of short life time. The gamma ray spectra were recorded by means of the hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. The long and short lived isotopes were considered. A comparative study and a discussion on the elemental concentration values are given.

关键词： elemental analysis Egyptian iron samples neutron activation analysis

Thermal and elemental analysis of the combustion chamber deposits in a large-scale two-stroke marine diesel engine

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Science China(Technological Sciences) 2015年第10期58卷 1717-1725页

作者： ZHANG XuSheng ZENG XiangMing SUN XiuCheng DENG Biao PENG GuanYun XIE HongLan WU ZhiJun XIAO TiQiao Merchant Marine College Shanghai Maritime University Shanghai Institute of Applied Physics Chinese Academy of Sciences School of Automotive Studies Tongji University

It is of significance to understand the chemical content of carbon deposits in the large-scale two-stroke(LSTS) marine diesel engine because of adverse effect on the engine performance, oil consumption and emissions. In this work, two different combustion chamber deposits in an LSTS marine diesel engine were studied using thermogravimetry analysis(TGA), elemental analysis(EA) and synchrotron X-ray fluorescence(SXRF). One was on the piston top and the other on the piston land, termed PTCD and PLCD, respectively. For the PTCD sample, the 97% residue in the TGA and 1.4% carbon content in the EA indicated the main compositions of PTCD were metal salts or oxides and ashes, significantly different from the previous findings of the highest carbon content in deposits from the small four stroke engines. The different chemical content between PTCD and PLCD implied higher thermal load in the LSTS marine diesel engine led to a nearly complete thermal decomposition of PTCD. The higher calcium content in PTCD and PLCD indicated the additives of cylinder oil should be the main source of metal content of PTCD and PLCD. Calcium distribution in the SXRF results was indicative of the potential layered structure in PTCD and PLCD. In addition, the appearance of iron on the surface against the piston in PTCD and PLCD indicated iron oxides formation between carbon deposit and piston materials.

关键词： combustion chamber deposits thermogravimetry analysis elemental analysis marine diesel engine synchrotron X-rayfluorescence spectrometry

Carbonization mechanism of bamboo (phyllostachys) by means of Fourier Transform Infrared and elemental analysis

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Journal of Forestry Research 2003年第1期14卷 75-79页

作者：左宋林高尚愚阮锡根徐柏森南京林业大学

通过测定在200-600℃炭化竹材得到的固体产物的碳、氢、氧元素的含量及它们的红外光谱,研究了在炭化过程中竹材中半纤维素、纤维素及木素的变化规律。结果表明,结合元素分析,红外光谱分析方法是研究竹材炭化机理的有效手段。在200℃以前... 详细信息

通过测定在200-600℃炭化竹材得到的固体产物的碳、氢、氧元素的含量及它们的红外光谱,研究了在炭化过程中竹材中半纤维素、纤维素及木素的变化规律。结果表明,结合元素分析,红外光谱分析方法是研究竹材炭化机理的有效手段。在200℃以前,竹材中的半纤维素和纤维素的大量羟基断裂,并结合成水而失去。在200-250℃之间,竹材中的纤维素被降解,其中的吡喃型环也遭到破坏。并且木素中的甲氧基也被脱去。竹材中的木素网状结构在250-400℃之间遭到完全的破坏。竹炭中的碳原子在600℃已基本上完成了芳环化。图3表2参15。

关键词： Bamboo Carbonization Fourier Transform infrared elemental analysis

Comparison of extraction abilities of deep eutectic solvents and aqueous acid solutions for extraction of rare earths and transition metals

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Journal of Rare Earths 2024年第6期42卷 1157-1164,I0006页

作者： Svetlana Drogobuzhskaya Margarita Frolova Andrey Shishov Nikita Tsvetov Tananaev Institute of Chemistry-Subdivision of the Federal Research Centre《Kola Science Centre of the Russian Academy of Sciences》 18420926a AcademgorodokApatityRussia Murmansk State Technical University 183010Sportivnaja str.13MurmanskRussia Department of Analytical Chemistry Institute of ChemistrySaint Petersburg State UniversitySpbSU.1990347/9 Universitetskaya embSt.Petersburg Russia

In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various ***-based deep eutectic solvents are most often used as extractants for the extraction of *** this work,for the first time,the extraction efficiency of transition metals and rare earth elements(Y,Zr,Nb,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Hf and Ta)from mining tailings and Na,K,Ca,Mg,Cu,Fe,Mn,Pb,Ba,Ni and Sr from biodiesel samples using acidic deep eutectic solvents and saturated aqueous solutions of the same acids(malonic,malic,tartaric and citric)is *** this,deep eutectic solvents based on acids and their aqueous saturated solutions were prepared and *** prepared mixtures were analyzed by IR spectroscopy to confirm the formation of eutectic *** such as the density and viscosity of the resulting mixtures were also investigated,as this can be of key importance for the efficiency of metal *** extraction of rare earth metals from mining tailings took a long time(up to several days),while the extraction of metals from fuel took no more than 30 *** emission spectral methods were used as an analysis *** is shown that the extraction efficiency with aqueous solutions is better than that with eutectic solvents,which casts doubt on the need for deep eutectic solvents use in this area.

关键词： Deepeutectic solvent Metal separation elemental analysis Rare earth metals Biodiesel

Dielectric and physico-chemical behavior of single thermally thick wood blocks under microwave assisted pyrolysis

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Particuology 2024年第3期86卷 291-303页

作者： Nicole Vorhauer-Huget Jakob Seidenbecher Supriya Bhaskaran Francesca Schenkel Lucas Briest Suresh Gopalkrishna Jan Barowski Andrea Dernbecher Liane Hilfert Ilona Rolfes Alba Dieguez-Alonso Otto von Guericke University Magdeburg Universitatsplatz 239106MagdeburgGermany Ruhr University Bochum Institute of Microwave SystemsUniversitatsstraβe 15044801BochumGermany

Pyrolysis of thermally thick beech wood blocks with a size of around 2.5×8×6 cm^(3)(width×length×height)was carried out in a lab scale microwave reactor with a frequency of 2.45 GHz,operated,both,at 300 W and 600 W under inert conditions,using N_(2) at around 400 mbar absolute *** microwave cavity had a size of 20×20×20 cm^(3).The specific energy supply referred to the untreated wood block was 4-8 W/g,with slight variations depending on the initial water *** mass loss and the reflected microwave power were in-situ monitored during the *** sample surface and chamber temperatures were measured with a pyrometer and a thermocouple,***-chemical and dielectric properties of the produced solids were investigated and compared to those of chars produced under conventional pyrolysis using the same raw *** is shown that the complex dielectric permittivity of the solid products changed drastically during the pyrolysis process,with increasing heating properties as the conversion process *** was easily achieved using 60o W without ***,300 W was not enough to achieve a high conversion degree,independently of the irradiation ***,together with the physico-chemical analyses of the solids,hinted to the importance of the transport kinetics in thermally thick materials,although further investigationis still required.

关键词： Microwave assistedpyrolysis Conventional pyrolysis Dielectric measurements Penetration depth elemental analysis

Chemical analysis of Hydroxyapatite Artificial Bone Powders by Energy Dispersive X-Ray Fluorescence Spectrometry(EDXRF)

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光谱学与光谱分析 2018年第8期38卷 2645-2649页

作者： O.K.Koksal G.Apaydin E.Cengiz L.Samek I.H.Karahan A.Tozar M.Lankosz Department of Physics Faculty of ScienceKaradeniz Technical University Department of Medical Physics and Biophysics Faculty of Physics and Applied Computer ScienceAGH University Science and Technology Department of Physics Faculty of Science and LiteratureMustafa Kemal University

Stoichiometric hydroxyapatite(HA)nanoparticles were synthesized by a wet chemical *** nitrate tetra hydrate used as calcium source and dibasic ammonium phosphate used as phosphorous *** nitrate tetra hydrate and dibasic ammonium phosphate solutions were prepared by dissolving the salts in distilled *** hydroxyapatite nanoparticles used by artificial bone powders and synthesized by a wet chemical method were analyzed using EDXRF *** concentrations of K,Ca,Ti,V,Cr,Fe,Ni,Cu,Sr and Pb for artificial bone powders have been ***,Calcium contents were evaluated according to the agitation time and temperature in the production process.

关键词： EDXRF X-ray Tube elemental analysis Hydroxyapatite

Characterization of humic acids extracted from the sediments of the various rivers and lakes in China

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Journal of Environmental Sciences 2008年第11期20卷 1294-1299页

作者： HE Mengchang SHI Yehong LIN Chunye State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

The humic acids (HAs) isolated from the sediments of the various rivers,lakes,and reservoirs in China were studied using elemental analyzer,fourier transform infrared (FT-IR),and CP/MAS 13C nuclear magnetic resonance (NMR) *** results showed that the HAs were characterized by some common chemical and physicochemical properties,but they also pose some differences in the C-containing functional *** C/N,C/H,O/C,and O/H ratios differ widely for the various HAs,showing that the elemental comp...

关键词： CP/MAS 13C NMR spectroscopy elemental analysis fourier transform infrared spectroscopy humic acids surficial sediment structural characteristics

SPECTRAL AND CHEMICAL MONITORING OF CYCLO-ADDITION REACTION OF CO_2 WITH POLY(MMA-co-GMA) COPOLYMERS

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Chinese Journal of Polymer Science 2012年第5期30卷 727-734页

作者： M.Yadollahi H.Bouhendi M.J.Zohuriaan-Mehr K.Kabiri Iran Polymer and Petrochemical Institute(IPPI) P.O.Box 14965-115TehranIran

This paper deals with the monitoring cyclo-addition of CO2 to methyl methacrylate （MMA）-glycidyl methacrylate （GMA） copolymers using spectral （IH-NMR and FTIR） and chemical （elemental analysis and titration） methods. Thus, poly（MMA-co-GMA）, was first prepared via solution polymerization. The copolymer was then treated with CO2 gas flow in the presence of cetyltrimethyl ammoniumbromide as a catalyst. In terms of the carbonation reaction time, the terpolymer poly（MMA-eo-GMA-co-2-oxo-l,3-dioxolane-4-yl-methyl methacrylate） was prepared in various yield of CO2 fixation （〉 90%）. The peak intensity changes in the 1H-NMR and FTIR spectra provided excellent demonstrative techniques to monitor the carbonation reaction progression. In a comparative analytical viewpoint, the NMR and elemental analysis were recognized to be the most accurate ways to follow the cyclo-addition reaction progression. However, titration was recognized to be the most preferred method, because it is a very inexpensive, facile and available method with a reasonable cost- accuracy balance.

关键词： Carbon dioxide Cyclic carbonate Glycidyl methacrylate Titration 1H-NMR elemental analysis FTIR.

Reoxidation process and corrosion behavior of TA15 alloy by laser ablation

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Rare Metals 2021年第4期40卷 865-876页

作者： Bo-Wen Liu Gao-Yang Mi Chun-Ming Wang School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

The thermal oxide layer formed of TA15 alloy has poor corrosion *** this paper,the changes of the elements and components on the surface after laser ablation with different energy densities(E) were *** formation process and corrosion behavior of laser-generated oxide layer were *** E increases,the oxygen content decreases from 8.52% to 5.43% and then increases to 11.89%.The surface oxide layer changes from TiO_(2)(R)(i.e.,rutile) to Ti_(2) O_(3)+TiO_(2)(R) and finally becomes TiO_(2)(R)+TiO_(2)(A)(i.e.,anatase).The TiO_(2)(R) gasification was confirmed by calculating the surface temperature *** surface reoxidation process was illustrated by a thermodynamically calculated ΔGT(i.e.,the Gibbs free energy changes with temperature).When E≥17.5 J·cm^(-2),the oxide layer exhibits an agitated morphology,and oxide falls off at the *** E increases,the corrosion rate decreases first and then *** energy density of 8.75 J·cm^(-2),the surface corrosion rate was 20.43 times slower than that of the untreated *** impedance spectrum and equivalent resistance results also prove the best corrosion resistance at 8.75 J·cm^(-2).The corrosion behavior of the oxide layer is analyzed from the properties of the oxide layer components and the reaction products with the electrolyte.

关键词： Laser ablation TA15 alloy Reoxidation process Corrosion behavior elemental analysis