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UV/visible spectroscopic analysis of CO^(3+) and CO^(2+) during the dissolution of cobalt from mixed Co-Cu oxidized ores

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 260-269页

作者： J. Ndalamo A.F. Mulaba-Bafubiandi B.B. Mamba Department of Chemical Technology University of Johannesburg Department of Extraction Metallurgy University of Johannesburg

The leaching of cobalt from four-mixed Co-Cu oxidized ores containing cobalt at levels ranging from 0.5wt% to 34wt% was studied and the results has been reported. Conventional dissolution of these oxidized Co-Cu ores with diluted H2SO4 and SO2 as a reducing agent resulted in a substantial improvement in the solution based recovery of cobalt. UV/visible spectroscopic analysis of the leached solu-tions indicated that the increased cobalt content in the solution was a result of flushing the acidified cobalt leaching solution with SO2. Fur-thermore, UV/visible spectroscopy confirmed that as SO2 was flushed into the acidified leaching solution, Co3＋ bearing minerals were re-duced to the readily soluble Co2＋ bearing minerals, and this resulted in the increase of total cobalt in the collected solution. The mechanism of the reduction of Co3＋ to Co2＋ bearing minerals when SO2 is flushed during the leaching of mixed Co-Cu oxidized ores, including the stability trends of Co3＋, Co2＋, and Cu2＋ complexes, as shown by their UV/visible spectra, are also discussed.

关键词： cobalt metallurgy dissolution leaching reaction kinetics spectroscopic analysis

Influence of inherent iron and oxygen concentrations on selenite sorption process using bentonite

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Science China Chemistry 2017年第9期60卷 1258-1264页

作者： Jiangang He Xueling Qiao Yanlin Shi Yao Li Xiaoyu Yang Wanqiang Zhou Chunli Liu Beijing National Laboratory for Molecular Sciences Fundamental Science Laboratory on Radiochemistry&Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The oxygen concentration and inherent Fe in bentonite have a significant influence on the Se(IV) sorption process. In this study, the sorption of selenite on natural bentonite was investigated using a batch experiment method, and the distribution coefficient (Kd) values were obtained in the pH range from 2.0 to 10.0 under oxic/anoxic conditions. The Kdvalues always reached a maximum value at a pH of 4 under oxic conditions and at a pH of 8 under anoxic conditions; meanwhile, the Kdvalue under anoxic conditions was larger than the value under oxic conditions, especially in regard to the maximum Kdvalues. The oxygen conditions have a significant influence on the ratio of redox-sensitive Fe2+/Fe3+, which was closely related to the difference in the Kdvalues under both oxic/anoxic conditions. Ferric selenite and green rust could be responsible for the maximum Kdvalues under oxic/anoxic conditions. In the leaching experiments, we found that the Fe2+in bentonite could replace Mg2+and Al3+in the octahedral sheet. Spectroscopy methods, such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) were used to characterize the surface properties of the samples after reaction. Overall, this study shows that the addition of Fe2+-containing materials into backfill/buffer materials under anoxic condition could enhance the sorption of79Se(IV). © 2017, Science China Press and Springer-Verlag GmbH Germany.

关键词： Bentonite Oxygen Sorption spectroscopic analysis X ray absorption spectroscopy X ray diffraction

spectroscopic study on transformations of dissolved organic matter in coal-to-liquids wastewater under integrated chemical oxidation and biological treatment process

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Journal of Environmental Sciences 2018年第8期30卷 206-216页

作者： Siwei Peng Xuwen He Hongwei Pan Department of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou 450045China

A large amount of wastewater containing various toxic organic contaminants is produced during coal-to-liquids process. In this study, several spectroscopic methods were used to monitor the transformation of organic pollutants during an integrated chemical oxidation and biological process. The results showed that the hydrophobic acid fraction increased after Fenton oxidation, which was likely due to the production of small-molecule organic acids. Soluble microbial products were generated during biological treatment processes,which were degraded after ozonation; meanwhile, the hydrophilic base and acid components increased. Ultraviolet-visible spectroscopic analysis indicated that peaks at the absorption wavelengths of 280 and 254 nm, which are associated with aromatic substances, were detected in the raw water. The aromatic substances were gradually removed, becoming undetectable after biological aeration filter（BAF） treatment. Fourier transform infrared spectroscopy analysis revealed that the functional groups of phenols;benzene, toluene, ethylbenzene, and xylene（BTEX）; aromatic hydrocarbons; aliphatic acids;aldehydes; and esters were present in raw wastewater. The organic substances were oxidized into small molecules after Fenton treatment. Aromatic hydrocarbons were effectively removed through bioadsorption and biodegradation after BAF *** organic matter was reduced and finally became undetectable after anoxic–oxic treatment in combination with a membrane bioreactor. Four fluorescent components were fractionated and obtained via excitation–emission matrix parallel factor analysis（EEM-PARAFAC）. Dissolved organic matter fractionation in conjunction with EEM-PARAFAC was able to monitor more precisely the evolution of characteristic organic contaminants.

关键词： Coal-to-liquids wastewater spectroscopic analysis Dissolved organic matter fractionation UV–visible spectrum Excitation–emission matrix parallel factor analysis (EEM-PARAFAC)

Fast Monte Carlo inversion for extracting the optical properties of tubular tissues

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Chinese Optics Letters 2008年第12期6卷 935-937页

作者：赵会娟周晓青梁菊兰张顺起 College of Precision Instruments and Optoelectronics Engineering Tianjin University

Reconstruction of absorption coefficient μa and scattering coefficient μs is very important for applications of diffuse optical tomography and near infrared spectroscopy. Aiming at the early cancer detection of cervix and stomach, we present a fast inverse Monte-Carlo scheme for extracting μa and μs of a tubular tissue from the measurement on frequency domain. Results show that the computation time for reconstructing one set of μa and μs is less than 1 min and the relative errors in reconstruction are less than ±10% for the optical properties of normal cervical tissue and precancerous lesions.

关键词： Diagnostic radiography Infrared spectroscopy Medical imaging Monte Carlo methods Optical properties Optical tomography Restoration spectroscopic analysis Tomography

Application of graphene oxides and graphene oxide-based nanomaterials in radionuclide removal from aqueous solutions

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Science Bulletin 2016年第20期61卷 1583-1593页

作者： Xiangxue Wang Shujun Yu Jie Jin Hongqing Wang Njud S. Alharbi Ahmed Alsaedi Tasawar Hayat Xiangke Wang School of Environment and Chemical Engineering North China Electric Power University Beijing 102206 China School of Chemistry and Chemical Engineering University of South China Hengyang 421001 China Biotechnology Research Group Department of Biological Sciences Faculty of Science King Abdulaziz UniversityJeddah 21589 Saudi Arabia NAAM Research Group Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia

With the fast development of nanoscience and nanotechnology,the nanomaterials have attracted multidisciplinary *** high specific surface area and large numbers of oxygen-containing functional groups of graphene oxides(GOs) make them suitable in the preconcentration and solidification of radionuclides from *** this paper,mainly based on the recent work carried out in our laboratory,the efficient elimination of radionuclides using GOs and GO-based nanomaterials as adsorbents are summarized and the interaction mechanisms are discussed from the results of batch techniques,surface complexation modeling,spectroscopic analysis and theoretical *** review is helpful for the understanding of the interactions of radionuclides with GOs and GO-based nanomaterials,which is also crucial for the application of GOs and GO-based nanomaterials in environmental radionuclide pollution management and also helpful in nuclear waste management.

关键词： Graphene oxides Radionuclides Sorption Interaction mechanism Theoretical calculation spectroscopic analysis

Spectral hole burning effects initiated by uniform signal intensities in a gain-flattened EDFA

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Chinese Optics Letters 2011年第2期9卷 11-14页

作者： A.R.Sarmani S-J Sheih F.R.Mahamd Adikan M.A.Mahdi Wireless and Photonics Networks Research Center Faculty of Engineering Universiti Putra Malaysia Taiwan International Securities Group Department of Electrical Engineering Faculty of Engineering Universitiy of Malaya

Spectral hole burning （SHB） effects in a gain-flattened erbium-doped fiber amplifier （EDFA） are demonstrated to be significant in the presence of large signal power around the 1530-1532-nm wavelength range. These are the first effects reported in a setup employing equivalent power level distribution of 40 channels ranging from 1530 to 1561 nm. To explain this, the introduction of a new local population variable into the laser equation is required to support the original inversion ratio that is determined by the pump lasers. In the analysis section, spectroscopic parameters and high signal powers are considered to be other contributing parameters to the change in the gain characteristics. An improvement to this theoretical basis is suggested by implementing mathematical modeling to validate similarities between the gain shape of simulation to that obtained in the experiment.

关键词： Erbium Fiber amplifiers Pumping (laser) spectroscopic analysis

China's progress in radionuclide migration study over the past decade(2010–2021):Sorption,transport and radioactive colloid

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Chinese Chemical Letters 2022年第7期33卷 3405-3412页

作者： Zongyuan Chen Siyuan Wang Huijuan Hou Kang Chen Pengyuan Gao Zhen Zhang Qiang Jin Duoqiang Pan Zhijun Guo Wangsuo Wu Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China The Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou 730000China Radiochemistry Laboratory School of Nuclear Science and TechnologyLanzhou UniversityLanzhou 730000China

The radionuclide(RN)migration study is not only helpful to understand environmental behavior of RNs,but also can establish the basis for the safety assessment of geological disposal of high-level radioactive waste(HLW).In the context of China’s HLW disposal,this review briefly summaries the progress of China’s RN migration studies over the past decade regarding three aspects,RN sorption,RN transport and radioactive *** studies from other disciplines(such as geology and environmental science)are also included in this review because they can provide references for the RN migration ***,China has achieved clear progress in RN migration study over the past decade,although large-scaled field experiments are lacked and a gap still exists comparing with the international advanced ***,several suggestions are proposed for future RN migration research in China.

关键词： High-level radioactive waste Sorption Transport Colloid spectroscopic analysis Theoretical calculation

The effect of salinity on Fucus ceranoides (Ochrophyta,Phaeophyceae) in the Mondego River(Portugal)

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Journal of Oceanology and Limnology 2019年第3期37卷 881-891页

作者： COTAS Joao FIGUEIRINHA Artur PEREIRA Leonel BATISTA Teresa Department of Life Sciences University of CoimbraCoimbra 3001-456Portugal MARE-Marine and Environmental Sciences Centre Faculty of Science and TechnologyUniversity of CoimbraCoimbra 3000-548Portugal Laboratory of Pharmacognosy Faculty of PharmacyUniversity of CoimbraCoimbra 3000-548Portugal LAQV REQUIMTEFaculty of PharmacyUniversity of CoimbraCoimbra 3000-548Portugal CIEPQPF Department of Chemical EngineeringFaculty of Science and TechnologyUniversity of CoimbraCoimbra 3030-790Portugal

Algae(and their extracts)are increasingly important for pharmaceutical applications due to the diversity of useful compounds they *** genus Fucus contains one of the most studied species,Fucus *** species *** differs from the others of the genus by presenting longitudinal air-vesicles and a capacity to survive at low *** is an alga that inhabits the Mondego River estuary(Portugal),at the southern limit of its distribution,and can serve as a role model to understand the effect of a salt gradient on the production of bioactive *** assessed the phenolic content and antioxidant activity of different *** extracts(***,aqueous and polysaccharide)prepared from samples harvested from two different zones to evaluate if the adaptation of *** to different salinity levels influenced its chemical *** antioxidant activity of the extracts was determined using 1,2-diphenyl-picrylhydrazyl(DPPH)and 2.2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)*** assays demonstrated that the methanolic extract of lyophilized *** that grew at low salinities was the most bioactive,***(IC 50=50.39μg/mL)and ABTS(TEAC=2.42).The total phenolic content(Folin-Ciocalteu method)and the methanolic extract of the lyophilized *** collected from a low salinity habitat exhibited the highest phenolic content(PGE=49.48μg/mg of lyophilized extract)amongst those *** layer chromatography(TLC)and Fourier transform infrared spectroscopy(FTIR)were used for the identification of compounds in the *** characterization allowed confirmation that the various extracts contained almost the same compounds but with notable quantitative *** on these results,we conclude that there were differences in the quantity of the compounds due to the effect of *** drying methods used were also found to have influenced the quality of the extracted compounds.

关键词： Fucus ceranoides salinity gradient sequential extractions phenolic content dependent bioactivities spectroscopic analysis

Raman spectroscopic study on Hela cells irradiated by X rays of different doses

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Chinese Optics Letters 2009年第8期7卷 734-737页

作者：齐健刘保良李云涛吴电勇唐伟跃 College of Physics and Engineering Zhengzhou University

Raman spectra are used for studying the structure and protein, nucleic acid, lipid, and carbohydrate contents, while cervical cancer cells irradiated by X rays of different doses are cultivated for 24 h. After irradiation by X rays, the following results are obtained. （1） Some 12-Gy groups move to the 1237-cm^-1 band in compared with the control group＇s 1240-cm^-1 band; after irradiation by 6-Gy X ray, the 1662-cm^-1 band of amide I has a blue shift of 10 cm^-1. The above two parts show that because of X ray irradiation, some proteins＇ random coil structures have transformed into β folding. （2） The 759-cm^-1 band disappear in the 6-Gy group; the 570-cm^-1 band of every group has a red shift, but the changes in intensity are different; the 1335-cm^-1 band in every group has a blue shift, and all their intensities increase. These show that although the 570-, 759-, and 1335-cm^-1 bands all belong to the tryptophan residue indole ring vibration, the molecular vibration energy structures which produce scattering lights are different. （3） The 786-cm^-1 band only has a blue shift of 3 cm^-1 in the 6-Gy group, and the non-hydrogen band of the phosphoric acid diester （O-P-O） increases. The frequency deviation of the 1089-cm^-1 band is erratic, and the bent symmetry stretch vibration conformation of phosphoric acid diester key （O=P=O） in the nucleic acid is complex. （4） The 1570-cm^-1 band has a blue shift, and its intensities all decrease, while the C=C conjugated duplet bond oxidizes, and the content of C=C decreases.

关键词： Amides Amino acids Carbohydrates Hydrogen Irradiation Nucleic acids Phosphoric acid Protein folding Raman spectroscopy spectroscopic analysis