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First-principle investigation on mechanism of Ca ion activating flotation of spodumene

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Rare Metals 2014年第3期33卷 358-362页

作者： fu-Shun Yu Yu-hua Wang Jin-Ming Wang Zhen-fu Xie Lei Zhang School of Minerals Processing and Bioengineering Central South University

Different hypotheses of the activation mechanisms of metallic ions for silicate minerals flotation were stated in this work. Spodumene and Ca ion were taken to illustrate this issue. Flotation test results and diagram of Ca ion species distribution vs pH show that the dominant hydrolyzed species are Ca（OH）？and Ca（OH）2, which is in correspondence with the maximum flotation recovery of spodumene. Density functional theory（DFT） calculation results reveal further that the precipitation of calcium hydroxide on spodumene surface is the effective process to activate the flotation of spodumene.

关键词： Spodumene flotation Ca ion Activationmechanism Density functional theory calculation

Effect of Atmospheric Interfering Absorption on Measurement of BTX by DOAS

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Chinese Journal of Chemical Physics 2008年第3期21卷 202-210页

作者： fu-min Peng Pin-hua Xie Hai-yang Li Ying-hua Zhang Jun-de Wang Wen-qing Liu Key Laboratory of Environmental Optical and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China College of Chemistry and Chemical Engineering Anhui University Hefei 230039 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

It was reported on the elimination of interfering absorption of BTX. the absorption of O2 includes different absorption bands, which change differently when the partial pressure of oxygen is varied. These cause the nonlinear absorption of O2 and the observed band shape to vary with the column density of O2. The absorption ratios of molecular absorption in each of the Herzberg bands and dimer absorptions, as well as the contribution to the correction error of molecular absorption, are studied based on the characteristic of these absorption bands. The optimized way to eliminate the interfering absorption is obtained in the end and the effectiveness of using interpolation proposed by Volkamer et al. to remove O2 absorption is proved again. As to O2 and SO2, the effect of the thermal effect of characteristic spectra on the elimination error of their absorption is studied. Solutions to these problems are discussed and demonstrated together with methods to optimize the interpolation of spectra. As a sample application, differential optical absorption spectroscopy （DOAS） measurements of BTX are carried out. Results show a low detection limit and the good correlation with point instruments are achieved. All these prove the feasibility of using spectral interpolation to improve the accuracy of DOAS measurements of aromatic hydrocarbons for practical purposes.

关键词： Differential optical absorption spectroscopy BTX Herzberg band O2 dimer

Comparison of phenolic profiles and antioxidant activities in skins and pulps of eleven grape cultivars(Vitis vinifera L.)

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Journal of Integrative Agriculture 2019年第5期18卷 1148-1158页

作者： LI fu-xiang LI fu-hua YANg Ya-xuan YIN Ran MINg Jian College of Food Science Southwest University Research Center of Food Storage & Logistics Southwest University Ernest Mario School of Pharmacy Rutgers University

Eleven grape cultivars were analysed to explore the variety differences of fresh grape phenolic profiles. The results showed that free phenolics were predominant in grape skins and pulps, and showed the higher antioxidant activities than bound. In 11 cultivars, Muscat Kyoho extracts had the highest total phenolic content in skins(10.525 mg gAE g^(–1) FW) and pulps(1.134 mg gAE g^(–1) FW), and exhibited the highest DPPH radical scavening capacity(EC_(50)=11.7 μg mL^(–1)) and oxygen radical absorbance capacity(ORAC) value(190.57 μmol TE g^(–1) FW) of free phenolic in skin. In addition, the most abundant phenolics in grape skins were found to be flavonoids such as kaempferol in Kyoho skin(541.2 μg g^(–1) FW), rutin, catechin and epicatechin in Muscat Kyoho skin(262.3, 86.3 and 70.0 μg g^(–1) FW, respectively). furthermore, the principal component analysis showed a strong difference of phenolic profiles with the cultivars, existing forms and distributions. Pearson correlation coefficient analysis showed a significant linear correlation between total phenolic content and antioxidant activity(Pg all samples.

关键词： grape phenolics varietal diversity antioxidant activity principal component analysis

On generalized Vector Equilibrium Problems

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Acta Mathematicae Applicatae Sinica 2006年第1期22卷 21-26页

作者： An-hua Wan Jun-yi fu Wei-hua Mao Department of Applied Mathematics South China Agricultural University Guangzhou 510642 China Department of Mathematics Nanchang University NaIlchang 330047 China

A new generalized vector equilibrium problem involving set-valued mappings and the proper quasi concavity of set-valued mappings in topological vector spaces are introduced; its existence theorems and the convexity of... 详细信息

关键词： Vector equilibrium problem set-valued mapping topological vector space KKM theorem

Effects of Metallic Ions on the Flotation of Spodumene and Beryl

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Journal of China University of Mining and Technology 2007年第1期17卷 35-39页

作者： WANg Yu-hua YU fu-shun School of Resources Processing and Bioengineering Central South University Changsha Hunan 410083 China

Effects of multivalent metallic cations, such as Ca2+ and Fe3+, on the flotation of spodumene and beryl were studied. The results show that Fe3+ and Ca2+ exhibit efficient activation on the flotation of spodumene and beryl. The ac- tivation of Fe3+ happens quite well within a pH range of 6-9 while the concentration of Fe3+ is 35 mg/L. Efficient acti- vation of Ca2+ takes place over at a pH over 11.6 at a concentration of 140 mg/L. The zeta potential of beryl and spo- dumene shifts slightly to positive values when activated by Ca2+, but markedly by Fe3+. New stretching frequencies of 1594.24 cm-1 and 1587.13 cm-1 have been found in the FTIR spectra of the two minerals after their interaction with Fe3+ and the collector. These new stretching frequencies are the asymmetric stretching frequencies of COO-(carboxyl anion), so thecollector may be chemically absorbed on the surface of Fe3+-activated beryl and spodumene.

关键词： spodumene beryl metallic ions activation flotation

The research on the high quality TiO_2, MoO_3-doped WO_3 electrochromic film

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Chinese Chemical Letters 2007年第7期18卷 883-886页

作者： Wei Luo Xiang Kai fu Li hua Ma College of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China

The high quality TiO2, MoO3-doped WO3 electrochromic film was prepared by the sol-gel method for the first *** sol, which has hydrogen peroxide （H2O2） and oxalic acid （H2C2O4）, was very stable at room temperature and quite suitable for the deposition of films. The WO3 electrochromic film prepared from this doped sol had excellent performance, such as short response time, no cracks, good adhesion to the substrate, high coloring efficiency and longevity of service.

关键词： TiO2 MoO3 WO3 Oxalic acid Sol-gel Electrochromic

Study and Application of Nb-V-Ti Microalloyed Cast Steel

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Journal of Iron and Steel Research International 2005年第3期12卷 56-59页

作者： HANJian-min LIUYuan-fu LIWei-jing LIRong-hua XUXiang-yang WANgJin-hua BeijingJiaotongUniversity Beijing100044China

A new type of Nb-V-Ti microalloyed cast steel was produced. Computer simulation was adopted to optimize the content of alloying elements. The microstructure of the microalloyed steel was analyzed. The fatigue property, wear and friction properties and rupture toughness of the steel were investigated. The service and operating properties of Nb-V-Ti microalloyed cast steel coupler were also examined. The results show that the steel has excellent comprehensive mechanical properties. The granular bainite structure and precipitation strengthening are the primary strengthening mechanism. The fine grain brings the steel good plasticity and excellent toughness. Various service and operating properties of Nb-V-Ti microalloyed cast steel automatic coupler are excellent.

关键词： microalloying cast steel microstructure mechanical property

Metallurgical Source of Cryogenic Intergranular Fracture of Fe-38Mn Austenitic Alloy

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Journal of Iron and Steel Research International 2000年第1期7卷 31-35页

作者： fu Rui-dong ZHENg Yang-zeng LI Shao-hua ZHOU Hui-hua Yanshan University Central Iron & Steel Research Institute Tsinghua University

SEM and Field emitting TEM-EDAX were used to investigate the fracture surface of series impact specimens and the grain boundary chemistries of VIM(vacuum-inductionmelted) Fe-38 Mn austenitic alloy before and after ESR(electroslag remelting,).The quantity and the size of inclusions were also *** results show that the VIM Fe-38 Mn austenitinic alloy water-quenched from 1 100 C undergoes an obvious ductile-to-brittle transition,and the impact work at ambient temperature is 242 J,the corresponding fracture surface exhibits a dimple ***,the impact work at 77 K of VIM alloy is only 25 J and the fracture mode is IgF(intergranular fracture).After ESR,the impact work at ambient temperature is 320 J and the fracture surface exhibits a character of "volcano lava"(meaning excellent toughness);The impact work at 77 K is up to 300 J and the fracture mode is micro void coalescence mixed with *** segregation of Mn is not found in all specimens,but the segregation of S is observed,and the S segregation is decreased after *** examined results of inclusions show that ESR reduces the quantity and improves the morphology of *** the above results it can be seen that the cryogenic IgF of VIM Fe-38 Mn austenitic alloy is related to the S segregation at grain *** ESR the decrease in the quantity and size of inclusion results in the increase of the impact work at ambient temperature,while the restriction of IgF is related to the decrease in the total level,and hence in the grain boundary segregation of S.

关键词： rich Mn austenitic alloy cryogenic intergranular fracture grain boundary segregation electroslag remelting

Effect of melt current on multi-physical field and heat flow distribution during ESR process based on model of dynamic formation of slag skin

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Journal of Iron and Steel Research International 2023年第6期30卷 1258-1267页

作者： fu-bin Liu Xin-hao Yu hua-bing Li Zhou-hua Jiang Hong-chun Zhu Xin geng School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

A numerical model coupled with a multi-physical field based on dynamic formation of slag skin is *** validation by comparing the experimental and simulation results of depth of metal pool,slag skin thickness and melt rate,it is utilized to investigate the effect of melt current on the coupled multi-physical field,slag skin thickness,metal pool depth and the heat flow distribution during electroslag remelting(ESR)Inconel 625 solidification *** results showed that with the increase in the melt current,the velocities of ESR system and the temperature of metal pool increased,whereas the highest temperature of slag bath firstly decreased and then *** the increase in the melt current,the slag skin thickness,metal pool depth and melt rate ***,the characteristics of the heat flow distribution and the effect of melt current on the heat flow distribution were analysed.

关键词： Electroslag remelting Melt current Slag skin Model Multi-physical field