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Rare Metals 2015年第3期34卷 202-206页

作者： Biao Wu he shang Jian-Kang Wen National Engineering laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals

By mineral liberation analyzer （MlA） automated quantitative system, the niobium-tantalum ore in this study was classified as refractory mineral of low-grade which was mainly composed of fergusonite, polycrase, ilmenorutile, and bastnasite. Most of niobium and rare earth metals were dis- seminated in these minerals （particle sizes of 95 % rare earth elements 〈40 μm）, which cannot be concentrated through traditional floatation process and treated by the current hydrofluoric acid leaching in industry application. It is nec- essary to develop a new approach to recovery these valuable metals. In this study, an improved method is proposed to extract these metals, which includes acid roasting and sulfuric acid leaching. The influence of mineralogy, acid concentra- tion, leaching temperature, leaching time, and liquid to solid ratio was experimentally studied. It is observed that after the ground ore （-74 μm） was roasted at 350 ℃ for 2 h with sulfuric acid （18.4 mol.l- 1） in the ore to acid mass ratio of 1：1, and then the roasting residue reacted with 25 % sulfuric acid at 90 ℃ for 2 h, the recovery rate of rare earth elements reaches 〉90 %, and the leaching extent of niobium can reach 84 %.

关键词： Niobium-tantalum Rare earth Refractory low-grade Roasting Sulfuric acid leaching

Solid-state reaction of a CaO−V_(2)O_(5)mixture:A fundamental study for the vanadium extraction process

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International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1462-1468页

作者： Jun-yi Xiang Xin Wang Gui-shang Pei Qing-yun huang Xue-wei lv College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China Chongqing Key laboratory of Vanadium-Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing 400044China

The aim of this study was to investigate the phase transformation and kinetics of the solid-state reaction of CaO−V_(2)O_(5),which is the predominant binary mixture involved in the vanadium recovery *** analysis,X-ray diffraction spectroscopy,scanning electron microscopy,and energy dispersive spectrometry were used to characterize the solid-state reaction of the *** extent of the solid reac-tion was derived using the preliminary quantitative phase analysis of the X-ray *** results indicate that the solid reaction of the CaO−V_(2)O_(5)mixture is strongly influenced by the reaction temperature and CaO/V_(2)O_(5)mole *** transformation of calcium vanadate in-volves a step-by-step reaction of CaO−V_(2)O_(5),CaO−CaV_(2)O_(6),and CaO−Ca_(2)V_(2)O7 depending on the CaO/V_(2)O_(5)mole *** kinetic data of the solid reaction of the CaO−V_(2)O_(5)(1:1)mixture followed a second-order reaction *** activation energy(Ea)and preexponential factor(A)were determined to be 145.38 kJ/mol,and 3.67×10^(8)min^(−1),respectively.

关键词： calcium vanadate vanadium extraction solid-state reaction kinetics

Pd catalysts supported on modified Zr_(0.5)Al_(0.5)O_(1.75) used for lean-burn natural gas vehicles exhaust purification

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Journal of Natural Gas Chemistry 2012年第4期21卷 393-399页

作者： hongyan shang Yun Wang Maochu Gong Yaoqiang Chen Key laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064SichuanChina

Composite supports Zr0.5Al0.5O1.75 modified by metal oxides, such as la2O3, ZnO, Y2O3 or BaO, were prepared by co-precipitation method, and palladium catalysts supported on the modified composite supports were prepared by impregnation method. Their properties were characterized by X-ray diffraction （XRD）, Nh3 temperature-programmed desorption （Nh3-TPD）, he temperature-programmed reduction （he-TPR）, N2 adsorption/desorption, and CO-chemisorption. The catalytic activity and the resistance to water poisoning of the prepared Pd catalysts were tested in a simulated exhaust gas from lean-burn natural gas vehicles with and without water vapor. The results demonstrated that the modified supports had an apparent effect on the performance of Pd catalysts, compared with the Pd catalyst supported on the unmodified ZrA1. The addition of ZnO or Y203 promoted the conversion of Ch4. In the absence of water vapor, Pd/ZnZrA1 exhibited the best activity for Ch4 conversion with the light-off temperature （Tso） of 275 ℃ and the complete conversion temperature （T90） of 314 ℃, respectively. however, in the presence of water vapor, Pd/YZrA1 was the best one over which the light-off temperature （Tso） of methane was 339 ℃ and the complete conversion temperature （T90） was 371 ℃. These results indicated that Pd catalyst supported on the modified composite ZrA1 support showed excellent catalytic activity at low temperature and high resistance to h20 poisoning for the exhaust purification of lean-burn natural gas vehicles.

关键词： modified Zr0.5Al0.5O1.75 palladium lean-bum natural gas vehicle methane oxidation water vapor

Effects of sludge dredging on the prevention and control of algae-caused black bloom in Taihu lake,China

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Journal of Environmental Sciences 2013年第3期25卷 430-440页

作者： Wei he Jingge shang Xin lu Chengxin Fan State Key laboratory of lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences University of Chinese Academy of Sciences

Algae-caused black bloom （also known as black water agglomerate） has recently become a critical problem in some Chinese *** has been suggested that the occurrence of algae-caused black bloom was caused by the cooperation of nutrient-rich sediment with dead algae,and sludge dredging was adopted to control black bloom in some lakes of *** this article,based on the simulation of black bloom using a Y-shape apparatus for modeling natural conditions,both un-dredged and dredged sites in three areas of Taihu lake,China were studied to estimate the effects of dredging on the prevention and control of black *** the experiment,drained algae were added to all six sites as an additional organic load;subsequently,the dissolved oxygen decreased rapidly,dropping to 0 mg/l at the sediment-water *** bloom did not occur in the dredged sites of Moon Bay and Nan Quan,whereas all three un-dredged sites at Fudu Port,Moon Bay and Nan Quan experienced black *** bloom also occurred at the dredged site of Fudu Port one day later than at the other sites,and the odor and color were lighter than at the other *** color and odor of the black water mainly result from the presence of sulfides such as metal sulfides and hydrogen sulfide,among other chemicals,under reductive *** color and odor of the water,together with the high concentrations of nutrients,were mainly caused by the decomposition of the algae and the presence of nutrient-rich ***,the removal of the nutrient-rich sediment by dredging can prevent the occurrence and control the degree of algae-caused black bloom in Taihu lake.

关键词： Taihu lake algae-caused black bloom sediment sludge dredging

Comparative proteomic study and functional analysis of translationally controlled tumor protein in rice roots under hg^(2+) stress

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Journal of Environmental Sciences 2012年第12期24卷 2149-2158页

作者： Feijuan Wang Yongshen shang ling Yang Cheng Zhu College of life Sciences Zhejiang UniversityHangzhou 310058China College of life Sciences China Jiliang UniversityHangzhou 310018China College of Chemistry and life Sciences Zhejiang Normal UniversityJinhua 321004China

So far, very little is known about mercury stress-induced intercellular metabolic changes in rice roots at the proteome level. To investigate the response of rice roots to mercury stress, changes in protein expression in rice roots were analyzed using a comparative proteomics approach. Six-leaf stage rice seedlings were treated with 50 μmol/l hgC12 for 3 hr; 29 protein spots showed a significant changes in abundance under stress when compared with the hg2＋-tolerant rice mutant and wild type （Zhonghua 11）. Furthermore, all these protein spots were identified by mass spectrometry to match 27 diverse protein species. The identified proteins were involved in several processes, including stress response, redox homeostasis, signal transduction, regulation and metabolism; some were found to be cellular structure proteins and a few were unknown. Among the up-regulated proteins, OsTCTP （translationally controlled tumor protein） was chosen to perform hetereologous expression in yeast which was presumed to participate in the hg2~ tolerance of rice, providing evidence for its role in alleviating hg2~ damage. Among the many tests, we found that OsTCTP-overexpressed yeast strains were more resistant to hg2＋ than wild-type yeast. Thus, we propose that OsTCTP contributes to hg2＋ resistance. here we present, for the first time, the functional characterization of OsTCTP in connection with hg2＋ stress in plants.

关键词： 2-DE mercury stress rice roots OsTCTP heteroexpression

An Anomalous Kerr loop of laBaMnO Thin Film

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Journal of Materials Science & Technology 1998年第4期14卷 371-373页

作者： hou, Bh Xu, Ql Ji, SZ Zhang, TP Peng, P shang, Ch Wang, YJ Xu, l Zhang, Y Univ Sci & Technol China Dept Phys Hefei 230026 Peoples R China Chinese Acad Sci Inst Phys State Key Lab Magnetism Beijing 100080 Peoples R China Chinese Acad Sci Inst Nucl Phys Shanghai 201800 Peoples R China

An anomalous Kerr loop was observed in an oriented laBaMnO film annealed in oxygen. Many tiny crystal columns were observed with scanning tunneling microscope and magnetic force microscope. The magnetic moment m in the column is perpendicular outward to the surface, which forms a surface phase with spin pinning state. This spin pinning results in the obvious asymmetrical Kerr loop of magneto-optical effect when the magnetic field is in the two opposite directions vertical to the surface.

关键词： Ferromagnetic materials

SST effect on the pre-monsoon intraseasonal oscillation over the South China Sea based on atmospheric-coupled GCM comparison

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Journal of Oceanology and limnology 2023年第2期41卷 409-417页

作者： Yun lIANG Yan DU shang-Ping XIE State Key laboratory of Tropical Oceanography&Key laboratory of Science and Technology on Operational Oceanography South China Sea Institute of OceanologyChinese Academy of Sciences&Innovation Academy of South China Sea Ecology and Environmental EngineeringGuangzhou 510301China College of Marine Science University of Chinese Academy of SciencesBeijing 100049China Peking University Chongqing Research Institute of Big Data Chongqing 401332China Southern Marine Science and Engineering Guangdong laboratory Guangzhou 510301China Scripps Institution of Oceanography University of CaliforniaSan DiegoLa JollaCA 92093USA

The role of sea surface temperature(SST)variability in the pre-monsoonal(April to July)intraseasonal oscillation(ISO)over the South China Sea(SCS)is investigated using the Community Earth System Model Version 2(CESM2).An Atmospheric Model Intercomparison Project(AMIP)simulation forced by daily sea surface temperatures(SSTs)derived from a parallel coupled general circulation model(CGCM)run was compared with observations and the mother coupled *** the coupled model,the SST warming leads the peak convection about 1/4 period as in *** paralell uncoupled model fails to simulate this phase relationship,implying the importance of air-sea coupling in reproducing realistic *** to the near-quadrature phase relationship between SST and precipitation ISOs during the ISO events,it is difficult to distinguish the active/passive role of SST from observations *** correlation in intraseasonal precipitation between the daily SST-forced AMIP and mother CGCM runs indicates that SST plays a role in driving the atmospheric ISO.

关键词： intraseasonal variability South China Sea Community Earth System Model Version 2(CESM2) sea surface temperature

Adsorption behavior of condensed phosphate on aluminum hydroxide

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Journal of Environmental Sciences 2007年第3期19卷 312-318页

作者： GUAN Xiao-hong ChEN Guang-hao shang Chii School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Department of Civil Engineering Hong Kong University of Science and Technology Hong Kong China

Sodium pyrophosphate （pyro-P, Na4P2OT）, sodium tripolyphosphate （tripoly-P, Na3P3O10）, and sodium hexametaphosphate （meta-P, （NaPO3）6） were selected as the model compounds of condensed phosphate to investigate the adsorption behavior of condensed phosphate on aluminum hydroxide. The adsorption was found to be endothermic and divisible into two stages：（1） fast adsorption within 1 h; and （2） slow adsorption between 1 and 24 h. The modified Freundlich model simulated the fast adsorption stage well; the slow adsorption stage was described well by the first-order kinetics. The activation energies of pyro-P, tripoly-P, and meta-P adsorption on aluminum hydroxide were determined to be 20.2, 22.8 and 10.9 kJ/mol P adsorbed, respectively, in the fast adsorption stage and to be 66.3, 53.5 and 72.5 kJ/mol P adsorbed, respectively, in the slow adsorption stage. The adsorption increased the negative charge of the aluminum hydroxide surface. Transmission electron microscopy and energy dispersive X-ray analysis analyses provided evidence that the adsorption was not uniform on the surface and that the small crystals contributed more to the fast adsorption than the normal sites did. The results from X-ray fluorescence spectrometry and X-ray photoelectron spectroscopy tests also revealed the uneven adsorption of condensed phosphate as a function of the penetration depth. More condensed phosphates were adsorbed on the outer surface of aluminum hydroxide than in its inner parts.

关键词： activation energy aluminum hydroxide condensed phosphate eutrophication surface charge

In situ FT-IR spectroscopy investigations of carbon nanotubes supported Co-Mo catalysts for selective hydrodesulfurization of FCC gasoline

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Journal of Natural Gas Chemistry 2008年第2期17卷 165-170页

作者： Jingcheng Zhang Wenkun Yin hongyan shang Chenguang liu State Key laboratory of heavy Oil Processing Key Laboratory of Catalysis CNPC College of Chemistry ＆ Chemical Engineering China University of Petroleum. Dongying 257061 Shangdong China

To better understand the nature of carbon nanotubes supported Co-Mo catalysts （Co-Mo/CNTs） for selective hydrodesulfurization （hDS） of fluid catalytic cracking （FCC） gasoline, studies are carried out using in situ Fourier transform infrared spectroscopy （FT-IR）. The catalytic performances of Co-Mo/CNTs catalysts were evaluated with a mixture of cyclohexane, diisobutylene, cyclohexene, 1-octene （60 ： 30 ： 5 ： 5, volume ratio） and thiophene （0.5%, ratio of total weight） as model compounds to simulate FCC gasoline. The hDS experimental results suggested that the hDS activity and selectivity of Co-Mo/CNTs catalysts were affected by Co/Mo ratio; the optimal Co/Mo atomic ratio is about 0.4, and the optimum reaction temperature is 260 ℃. The in situ FT-IR studies revealed that 1-octene can be completely saturated at 200 ℃. In the FT-IR spectra of diisobutylene, the characteristic absorption peak around 3081 cm^-1 for the stretching vibration peak of =C-h bond was still clear at 320 ℃ indicating that diisobutylene is difficult to be hydrogenated. As for the thiophene, no characteristic absorption peak could be found around 3092 cm^-1 and 835 cm^-1 when the reaction temperature was raised to 280 ℃, indicating that thiophene had been completely hydrodesulfurized. On the basis of FT-IR results, it can be deduced that thiophene hDS reaction occurred mainly through direct hydrogenolysis route, whereas thiophene hDS and diisobutylene hydrogenation reaction over Co-Mo/CNTs catalysts might occur on two different kinds of active sites.

关键词： in situ FT-IR hydrodesulfurization carbon nanotubes hydrogenolysis thiophene FCC gasoline

A Simplified Rational Representation for Positive-Dimensional Polynomial Systems and ShEPWM Equations Solving

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Journal of Systems Science & Complexity 2017年第6期30卷 1470-1482页

作者： shang Baoxin ZhANG Shugong TAN Chang XIA Peng School of Mathematics Key Laboratory of Symbolic Computation and Knowledge Engineering (Ministry of Education) Jilin University College of Science Northeast Electric Power University College of Science Northeast Forestry University School of Mathematics Liaoning University

The paper is concerned with the improvement of the rational representation theory for solving positive-dimensional polynomial systems. The authors simplify the expression of rational representation set proposed by Tan and Zhang(2010), obtain the simplified rational representation with less rational representation sets, and hence reduce the complexity for representing the variety of a positive-dimensional ideal. As an application, the authors compute a "nearly" parametric solution for the ShEPWM problem with a fixed number of switching angles.

关键词： Positive-dimensional polynomial system solving rational univariate representation ShEPWM simplified rational representation