bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Praseodymium Salt on Properties of Anodic Aluminum Oxide Films
Authors: Liu Xiao Zhen , Liu Zhao Xin , Yu Ai Bing , Wang Gang , Song Ling Ling , Ding Le Qi
Published: December 2011

Praseodymium salt was used as additives for the first time in preparing anodic aluminum oxide (AAO) films to improve its performance. AAO films were prepared by anodization method from a 15 vol.% sulphuric acid solution containing praseodymium salt. The effects of Pr concentration on microhardness and thickness of AAO film were investigated, respectively. The effect of heat treatment temperature on structure of AAO film was investigated. AAO films were characterized by XRD, EDAX and SEM techniques. AAO films showed higher microhardness and thickness, the surface of AAO film was smoother and the aperture of AAO film was more uniform than those of films prepared in 15 vol. % sulphuric acid anodization solution. The microhardness and thickness of AAO film were 355.7HV and 84μm respectively. The apertures of AAO film were in 25～30nm. There was not praseodymium in AAO film. AAO films were amorphous when heat treatment temperatures of AAO film were below 800°C. When heat treatment temperature of AAO film were 850°C and 1000°C respectively, AAO films were γ-Al2O3 and α-Al2O3 film respectively.
Thermodynamic Analysis of the Reduction of Na2WO4 through the Mechanochemical Reaction
Authors: Gao Yuan Hong , Yang Jian Gao , Su Bai Tao , Chen Lian Ping
Published: December 2011

Hydrogen is widely used to prepare tungsten from tungsten oxides. Such a gas is combustible and strict measures must be taken. However, assisted by Mg or Li3N, tungsten can be prepared through the ball milling at room temperature. Al powder is supposed to be one of the proper reducers. Simulations on the loss of Gibbs energy of these reactions have been investigated. Studies reveal that the reduction of Na2WO4 is feasible when reducers such as Al, Mg and Li3N are used; and the intermediate tungsten oxides such as WO2, WO2.72 and WO2.9 can be seldom generated. In addition, the calculation favors that NH3 does not react with Na2WO4 or WO3 theoretically.
Effect of Processing Parameters on the Properties of Glass–Ceramics from Arc-Melting Slag of Incineration Fly Ash
Authors: Liu Han Qiao , Wei Guo Xia , Liang Yin , Yang Jun Lan
Published: December 2011

The glass-ceramics were made of arc-melting slag from incinerator fly ash mixed with glass cullet additive by sintering method. The effects of ball milling time and powder compaction pressure on the microstructure, physical and mechanical properties of the glass–ceramics were respectively investigated. Results showed that with milling time delaying, granularity of the parent glass evidently reduces, the major phases of glass–ceramics have no change but the diffraction peaks present intensive trend, the crystal sizes of glass–ceramics decrease, the properties such as volumetric densities, compressive strength, bending strength and toughness are improved, the appropriate milling time is 6h with fifty percent of the volume (d50 value) of 10.62μm. The physical and mechanical properties first increase and then decrease with compaction pressure increasing, and the optimal compaction pressure is 60MPa.
Optical Properties of Two Novel Terbium Thermo-Sensitive Poly(N-Isopropylacrylamide) Gels
Authors: Zheng Yu Hui , Tan Chao Liang , Wang Qian Ming
Published: December 2011

Two novel silica based terbium complexes (Tb(Bipy)3 and Tb(Tyr)3) were encapsulated into poly(N-isopropylacrylamide) and two hydrogels with intense green emission were developed. The variation of intensity changes by Tb(III) 5D4 → 7F5 transition indicated the gradual reduction tendency upon the increasing temperature. The declined luminescence behaviors of the two gels undergo the linear decay process (5~30°C). During lower critical solution temperature (33°C) stage, the emission responses significantly improved unexpectedly. Moreover, the terbium emissive species-loaded hydrogels exhibited much enhanced mechanical properties than pure gel.
Syntheses, Crystal Structures and Luminescence of Two Coordination Polymers Based on Isophthalic Acid and 2-(3-Pyridyl)benzimidazole Ligands
Authors: Yue Ke Fen , Zhao Shuang , Zhao Rui Li , Wang Yao Yu
Published: December 2011

Two new coordination polymers, [Zn(PyHBIm)2(IPA)]•3H2O (1), [Cd(PyHBIm)(IPA)(H2O)2]•2H2O (2), were synthesized under hydrothermal conditions based on 2-(3-pyridyl)benzimidazole (3-PyHBIm) and isophthalic acid (IPA). The complexes were characterized by single crystal X-ray diffraction. They contain simple 1D chains and can be assembled into a 3D network through aromatic π–π stacking interactions and hydrogen bonding interactions. Their luminescent properties were studied in the solid state at room temperature.
Experimental Study on Solidification of Copper-Iron Alloys during Wedge-Mold Casting
Authors: Zhang Hai Tao , Li Bao Mian , Cui Jian Zhong
Published: December 2011

The effect of cooling rate and iron content on the solidification of copper-iron alloys during the wedge-mold casting had been investigated in this paper. The experimental results show that the morphology of as-cast structure is mainly determined by iron content and the grain size is affected by both the iron content and cooling rate. The as-cast structure is obviously refined and its morphology changes gradually from columnar grains to equiaxed ones with the increase in iron content. When iron content is greater than 3% (wt%) the as-cast structure is composed of equiaxed grains. With the increase in cooling rate the as-cast structure is gradually refined and primary γ-Fe phase is gradually scattered uniformly throughout the matrix.
Mixed-Phase Crystallization and Visible Fluorescence in Rare-Earth Ions Doped Germanate Glass-Ceramics
Authors: Li Yu Hua , Zhang Xiang Ling , Fan Cun Xi , Liu Ming , Zhai Bin , Lin Hai
Published: December 2011

Rare-earth doped glass-ceramics were prepared by heat-treating the precursor germanate glasses. The crystalline phases of the glass-ceramics were assigned to be NaAlGeO4 (NAG) and Mg2GeO4 (MG), and the primary particle sizes were derived to be ~31 and ~32nm, respectively. The secondary particle size of crystal grains was estimated to be ~30µm, and the large grain size is owing to the particles aggregation. Under 254 and 365nm radiation, Sm3+-doped glass-ceramics exhibit orange and reddish-orange fluorescences, and Eu-doped glass-ceramics present red and purplish-red lights, respectively. The investigation results of excitation spectra indicate that the Sm3+- and Eu-doped NAG-MG glass-ceramics can be excited efficiently by commercial UV and blue laser diodes, as well as blue and bluish-green LEDs.
Synthesis and Luminescent Properties of Y2O3:Eu3+ Nanocrystal by the Ultrasonic Method
Authors: Yu Hong Quan , Wang Hong Dan , Li Tao , Chen Bao Jiu
Published: December 2011

Rare-earth luminescence materials in lighting the tube and the field emission fields has been widely applied.In the leds, special security lights and energy-saving lighting are in the areas of infinite good prospect, this paper the research progress of preparation and a concrete discussion . The ultrasonic method for Y2O3:Eu3+ nanocrystal, annealing conditions on the Y2O3:Eu3+ nanocrystal particles size, crystal condition and the influence of the luminescence properties.The properties of the Y2O3:Eu3+ complexes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Reaction conditions, such as ultrasonic power and the temperature were found to have close relation with the morphologies of final products.
Highly C-Axis Oriented Barium Titanate Ferroelectric Films Deposited on SrTiO3 Substrate Using an Off-Axis Sputtered Conductive Oxide Layer as Bottom Electrode
Authors: Zhang Wei , Yuan Mei Ling , Wang Xian Yang , Ouyang Jun
Published: December 2011

BaTiO3(BTO) thin films were grown on (100) SrTiO3(STO) single crystal substrates using the RF-magnetron sputtering technique (RFMS) in both pure argon and mixed Ar/O2(20% O2) atmosphere. A La0.5Sr0.5CoO3(LSCO) layer was deposited as the bottom electrode by a 90° off-axis single-target RFMS. θ-2θ X-ray diffraction measurements showed that BTO thin films grown in both cases had a highly preferred c-axis orientation (001). From hysteresis measurements, it was confirmed that both films are ferroelectric. The ferroelectric polarizations 2Pr were 6.6 μC/cm2and 27.1 μC/cm2, for the BTO films grown in pure argon and in mixed Ar/O2atmosphere, respectively.
Synthesis, Photochromism and Optical Storage of a New Type of Diarylethene Compound
Authors: Wang Li Qin , Pu Shou Zhi , Yan Liu Shui , Cui Shi Qiang
Published: December 2011

A new unsymmetrical photochromic diarylethene 1-(2-methylbenzothiophene-3-yl)-2-(2-nbutyl-5-(2,2′-dicyanovinyl)thiophene-3-yl)perfluoroncyclopen-tene (1a), was synthesized and its optoelectronic properties, such as photochromism in solution as well as in poly-methylmethacrylate (PMMA) amorphous films, and the fluorescence spectra of diarylethene 1a was investigated. The photochromic reaction kinetics indicated that the cyclization process of 1a belongs to the zeroth order reaction and the cycloreversion process belongs to the first order reaction. The diarylethene can be potentially used as holographic optical recording medium.
Investigation on the Morphologies of Dislocations in Sapphire Crystals
Authors: Sun Yu , Chen Hong Jian , Yan Wen Bo , Liu Cai Chi
Published: December 2011

Sapphire single crystal is widely used in a variety of modern applications from GaN-based LED to military optical systems because of its excellent combination of optical, mechanical, thermal and chemical properties. The dislocations affecting the quality of sapphire crystal were studied by chemical etching and optical microscopy in this paper. The experimental results showed that the dislocation corrosion pits of (11-20) plane in sapphire crystals grown by Kyropoulos method is diamond-shaped and (1-102) plane is isosceles triangle and the density of dislocations in samples grown by Czochralski method is about two orders of magnitude higher than that in samples grown by Vertical Bridgman method. The formation mechanism of defects and proposes was also discussed.
Photoluminescence Properties of Sm3+-Doped La2O3 Powders
Authors: Xiao Qi , Zhu Gao Yuan
Published: December 2011

The Sm3+-Doped La2O3powders were prepared by precipitation method. The room temperature photoluminescence (PL) spectra of Sm3+-Doped La2O3powders doped with different Sm3+concentration excited at 405 nm have been investigated. The PL spectra showed three main strong emissions peaks at near 572, 613, and 657 nm, which were due to the f-f forbidden transitions of the 4f electrons of Sm3+, corresponding to4G5/2→6H5/2(572 nm),6H7/2(613 nm), and6H9/2(657 nm), respectively. The optimum Sm3+concentration in La2O3powders for optical emission was determined to be 2.0 %. Since the 2% Sm-doped La2O3 offer a rather strong f–f transition excitation in near the UV region, the as-prepared phosphors are likely to be used as potential red phosphors for near-ultraviolet (370-410 nm) light-emitting diodes (LEDs).
Electrochemical Synthesis and Photovoltaic Properties of Polythiothene/CdSe Double Layers Electrode
Authors: Hao Li Ping , Niu Hai Jun , Hao Li Na , Bai Xu Duo , Wang Wen
Published: December 2011

The electrochemical deposition of thiophene and CdSe on TiO2/ITO by cyclic voltammetry(CV) technique was carried out to study the influence of conditions on the preparation and photophysical performance of poly(thiophene) (PTh)/CdSe double layers electrode. The chemical structure of the obtained polymer was characterized by FT-IR, Raman, X-ray diffraction, UV-vis spectroscopy. The morphology was observed by electronic scanning microscope (SEM) which showed nano-grain shape. Finally the photovoltaic performance of the solar cell which was composed of PTh/CdSe/TiO2 composite film used as working electrode, Pt used as counter electrode was investigated. And mechanism of photogenerated electron of PTh/CdSe electrode was proposed. The results showed that TiO2electrode modified by PTh/CdSe composite film had good response on irradiation, which indicated the PTh/CdSe was promising dye in solar cell.
Synthesis and Luminescent Properties of M2P2O7:Eu3+ (M = Ca, Sr, Ba ) Phosphors
Authors: Mo Fu Wang , Wang Rong Fang , Lan Yu Wei , Zhou Li Ya , He Tao , Xu Xian Mei
Published: December 2011

A series of orange-red phosphors M2P2O7: Eu3+ (M = Ca, Sr, Ba ) were prepared by traditional solid-state reaction method. X-ray diffraction analysis confirmed the formation of Ca2P2O7, Sr2P2O7 and Ba2P2O7. Scanning electron-microscopy observation indicated a narrow size-distribution of about 0.6~1 μm for the particles with a quadrate shape. Photoluminescence spectra of M2P2O7(M = Ca, Sr, Ba ): Eu3+ phosphors showed a strong excitation peak around 393 nm, and Ca2P2O7: Eu3+, Sr2P2O7: Eu3+ and Ba2P2O7: Eu3+ phosphors showed strong emission bands peaking at about 593 nm, which suggests that the Eu3+ ion is occupy the site with center of symmetry.
The 3d Electrons and Microdefects in Binary Ti-Al Alloys Studied by Positron Annihilation
Authors: Deng Wen , Guo Xiao Lei , Xie Bing , Xiong Ding Kang , Huang Yu Yang
Published: December 2011

The behavior of 3d electrons and microdefects in binary Ti-Al alloys with Al contents from 47at.% to 53at.% have been studied by coincidence Doppler broadening and positron lifetime techniques. It has been found that the 3d electron signals in the spectra of binary Ti-Al alloys increase with Ti content. In Al-rich Ti-Al alloys, on increasing Al content, the open volume of defect on grain boundary increases while the density of free electron decreases. On the contrary, in Ti-rich Ti-Al alloys, on increasing Ti content, the open volume of defect on grain boundary decreases, and the electron density of the grain boundary increases.
Isothermal Experimental Study on the Effects of Converter Bath Shape on the Melt Mixing
Authors: Duan Jian Feng , Cang Da Qiang , Zhang Ling Ling , Xu Dong , Qin Li Xue
Published: December 2011

The effects of the bath shape, oxygen lance nozzles structure, and lance level on liquid steel mixing time and splashing amount were studied by experiment orthogonal design with 1:10 water model for 100 t basic oxygen converter modeling. The results showed that the stirring effect in the bath can be improved by changing the shape on the bath surface around the furnace wall with arc-shaped structure which can shorten the mixing time and reduce the liquid slag and steel splashing amount of the lining, and result in reducing metal lose and prolong the life of the lining.
Application of Simulated Annealing Algorithm in Sintering Burdening Optimization
Authors: Chang Jian , Su Bu Xin , Zhang Jian Liang , Cao Wei Chao , Guo Hong Wei , Ren Shan
Published: December 2011

Sintering burdening optimization has great value in reducing sintering cost and improving sinter qualities. Considering the nonlinear relationship between the high temperature characteristic parameters of iron ores in sintering, this article introduces the simulated annealing algorithm into burdening calculation and establishes a mathematic model of sintering burdening optimization. The initial parameters in simulated annealing algorithm are determined through tentative experiments, including initial temperature, cooling function, annealing constant and the end condition. The model can effectively reduce sintering cost and improve sinter qualities in its practical use.
Research and Application of the New Technologies on Blast Furnace at Shougang Qiangang Plant
Authors: Zhang Fu Ming
Published: December 2011

In recent years great progress is made in technical equipment of large blast furnace in China. A series of new process, technologies and equipment, integrated and developed on our own, are applied on newly built large blast furnaces and have been proved to be highly effective. After more than 20 years’ development and innovation of the bell-less top equipment designed and developed on our own, it has reached the advanced level in the world in terms of equipment reliability and service life; fully-dry impulse bag filter dedusting technology of BF gas, which is also developed on our own, has gained technical breakthroughs in terms of optimized system design, gas temperature control, pneumatic conveying of dedusting fines; the integrated innovative high-efficiency long-life high-temperature technology, through applying high-temperature preheating technology of combustion air, improving heat transfer efficiency of hot blast stove and optimizing structure of the hot blast stove system, enables the blast temperature to reach 1250°C with BF gas as fuel.
Numerical Simulation and Optimization Practice of Oxygen Lance for Converter Steelmaking
Authors: Chen Yong , Liang Xin Teng , Zeng Jian Hua , Chen Jun , Liu Rong Di
Published: December 2011

The lance system is one of the important link of converter. Stable and secure of the system is a necessary condition for whole production system to function normally. The numerical simulation for a three-dimensional oxygen lance nozzle was carried out according to the fundamental parameters of PZH steel, the characteristics of the oxygen jet were analyzed and discussed. The oxygen lance nozzle with the optimum design has achieved good results in practice: the average formation time of early slag was reduced by 1 min and 23 seconds, the pure blowing time was reduced by 46 seconds, the oxygen consumption per ton steel decreased by 1.05 m3/t, the rate of dephosphorization was increased by 1.35%, the basicity of slag was reduced by 0.38, the phosphorus and sulfur distribution ratio between slag and liquid iron were also increased effectively.
Modeling Investigation of the Oxidation Kinetics of Copper and Aluminum Alloys
Authors: Jin Feng , Luo Qun , Zhou Biao , Li Qian
Published: December 2011

The oxidation kinetics of copper or aluminum added with magnesium was investigated by a modified Chou model. The effect of the addition of magnesium in copper or aluminum was discussed. The calculation results showed that the activation energy of CuMg0.34 was the highest among Cu-Mg alloys at 600-900 °C, which indicated that it had the best oxidation resistance in all of the samples. The aluminum alloy AA3004 containing 1.0 wt.% Mg showed the better anti-oxide behavior than AA5182 with 4.0 wt.% Mg, and the relation between oxidation rate and oxygen partial pressure could be expressed as 0.71 times power law.
Strength and Consolidation Mechanism of Green Pellets Containing Carbon
Authors: Wei Ru Fei , Li Jia Xin , Tang Guang Wu
Published: December 2011

The effects of four inorganic binders and four organic binders on strength of green pellet containing carbon were studied. The results show that phenolic resin is the best binder, compressive strength and drop strength of preheated pellet are 312.5 N and 15.1 times, respectively, when the matching was 2%. The reason is that chemical adsorption effect occurs in pellet. Strength of wet pellet is mainly maintained by capillary force. However, preheated pellet is mainly maintained by chemical adsorption effect and viscous force. Chemical adsorption effect is better than viscous force.
Determination of Surface Tension of the Freeze Slag in Reaction Shaft of Flash Smelting Furnace
Authors: Wang Jin Liang , Wu Yan Xin , Liang Li Wei
Published: December 2011

According to the reaction shaft operation characteristics during the flash smelting process, 15 groups of slag samples containing high Fe3O4were prepared by some chemical reagents, and then the slag surface tensions were measured using a RTW-10 type synthetic test instrument for melt physical property by means of suspension link. The effects of temperature ( T ), basicity ( B ), the Fe/SiO2ratio (mFe/mSiO2), Fe3O4content (ωFe3O4), Cu2O content (ωCu2O), MgO content (ωMgO) and CaO content (ωCaO) on the slag surface tension (δ) were also studied. Results show that δ fluctuate between 0.3N/m to 0.8 N/m, and is increased with the increase of T, B, mFe/mSiO2, ωCu2O, ωMgOand ωCaO, and with the decrease of ωFe3O4, under the range of slag contents: mFe/mSiO21.36~1.78, ωFe3O417.83%~21.18%,ωCu2O3.51%~8.34%,ωMgO2.21%~6.57%,ωCaO6.22%~9.87% and the temperature range of 1380°C to 1500°C. To make the freeze slag adhere to the reaction shaft inner wall easily, the Fe3O4content in freeze slag should be increased and the inner chamber temperature of reaction shaft should be controlled appropriately.
Phosphorus Distribution Equilibrium between CaO-FeO*-SiO2-P2O5(15%)-CaF2(B2O3) Slag System and Carbon-Saturated Hot Metal at 1573K
Authors: Zhou Jin Dong , Bi Xue Gong , Huang Zhi Cheng , Wen Zhi Jun , Yang Fu , Jin Yan
Published: December 2011

In order to understand the equilibrium condition of phosphorus between slag and hot metal saturated with carbon in the high phosphorus hot metal dephosphorization process, the dephosphorization capacity of CaO-FeO*-SiO2-P2O5(15%) -CaF2(B2O3) slag system at 1573 K was studied, by applying the method that phosphorus distribution ratio between slag and solid iron was firstly measured and the one between slag and hot metal was then calculated. The results showed that phosphorus distribution ratio decreased with increase in basicity of CaO/(SiO2 +P2O5), a proper increase in SiO2 content is helpful to the absorption of phosphorus into slag, an increase in FeO* content from 10.52% to 13.40% resulted in a dramatic reduction of phosphorus distribution ratio from 126.43 to 33.25, by completely substituting CaF2 with B2O3 at 2.5 of basicity and 0.07 of B2O3/CaO ratio not only was acquired a high phosphorus distribution ratio of 171, but also was decreased pollution to the environment.
Study on the Removing of Ammonia Nitrogen in Ammonium Paratungstate Crystal Parent Solution
Authors: Wan Lin Sheng , Gong Dan Dan , Fu Zan Hui , Li Hong Chao , Sun Li
Published: December 2011

We realize the goal of removing ammonia nitrogen in ammonium paratungstate crystal parent by using strong sodium tungstate liquid to transform-magnesium salt to take off ammonium thoroughly. The results show that removal rate of ammonia can up to 98.88%, ammonia nitrogen contented in the liquid can down to 0.042g/l. Diluting sodium tungstate solution which has been disposed through the above way can be used to confect liquid before the ion exchange,the liquid with the ion exchange can reach the national effluent standard..
Kinetics of Pressure Acid Leaching of Zinc from Zinc Silicate Ore
Authors: Xu Hong Sheng , Wei Chang , Li Cun Xiong , Song Yan , Deng Zhi Gan , Fan Gang
Published: December 2011

The present work is concerned with the kinetic study of pressure leaching of zinc silicate ore in sulfuric acid solutions. The effects of leaching temperature, particle size, sulfuric acid concentration and agitation speed on the zinc extraction were evaluated. The results obtained show that the zinc extraction increases with increasing sulfuric acid concentration and leaching temperature. The leaching kinetics was analyzed by using a shrinking core model with diffusion control given by: 1-2/3x-(1-x)2/3=Kt, which represented well the experimental data. The apparent activation energy was determined to be 44.56kJ/mol at temperatures ranging between 80 and 140°C.
Calculating Model of FetO Activity in Alkali-Containing BF Slag
Authors: Li Jian Chao , Kong Yan Chang , Lü Qing , Li Fu Min
Published: December 2011

The FetO activity calculating model of alkali-containing BF slag was built according to the coexistence theory of slag structure at 1773K. The results reveal: it is correspond to reality and embody the structural characteristics of BF slag. The FetO activity of slag increases obviously with the w(CaO)/w(SiO2) increasing, decreases with the Al2O3 and MgO contents increasing.
Material Ratio Optimization of Low Mass Ratio of Alumina to Silica of Calcium Aluminate Slag Based on Thermodynamic Calculation Method
Authors: Tong Zhi Fang , Xie Sen Lin , Zhang Li Heng , Chen Tao , Liu Wei , An Gui Huan
Published: December 2011

For the low m(Al2O3)/m(SiO2) (mass ratio, for short A/S) calcium aluminate slag obtained from smelting reduction Pingguo red mud, the impact of different n(CaO)/n(Al2O3))(molar ratio, for short C/A) and A/S on the separateing out phase of slag in cooling and solidification process was studied by FactSage thermodynamic calculation software, and the material ratio of the slag was optimized. The physical-chemical properties of slag prepared in the experiment were analyzed by means of XRD, EMS, EDS, Particle size analysis and Chemical analysis. The thermodynamic calculation results indicate that the effect of C/A on the phase composition of the slag is great, but the influnce of A/S from 0.5 to 1.0 is small, the material ratio optimized is C/S=2, A/S=0.5～1.0, C/A=1.61～1.81, under the conditions, the phase composition is mainly Ca2SiO4, Ca12Al14O33and even a small amount of less than 5% of CaAl2O4or Ca3Al2O6. The phase composition of experimental slag is consistant with that of thermodynamic calculation. In the material proportion optimized scope, the calcium aluminate slag has better the self-disintegrating and the alumina leaching performance, and satisfies completely the technological requirements of extracting alumina. The results provide the scientific basis for using the low A/S calcium aluminate slag obtained from smelting reduction Pingguo red mud producting alumina.
Nickel Loss during Iron Precipitation and Product Characterization
Authors: Wang Kai , Li Jian , McDonald R.G. , Browner R.E.
Published: December 2011

In this study, the iron precipitation and associated nickel loss from synthetic ferric and nickel sulphate solutions were investigated. Two types of common neutralizing agents, magnesium oxide and calcium carbonate were applied in the investigation. The results indicated that pH and temperature had significant impacts on nickel loss during the iron precipitation process, whereas the type of neutralizing agents had little effect. It was found that increasing in pH and temperature resulted in more nickel loss in the pH range of 2 to 4 and temperature range of 25 to 85 °C. Mineralogical examination by XRD indicated that the iron precipitates were combinations of schwertmannite, ferrihydrite and goethite. In addition, more crystalline goethite was formed from the ferric solutions when no nickel was present, indicating that nickel might play a role in inhabiting the crystallization of goethite.
Investigations of Alloying Elements and Rare Metals on the Hydrogen Content and Inclusion in Aluminum Alloy
Authors: Li Xie Hua , He Li Zi , Cao Yi Heng , Zhu Pei , Cui Jian Zhong
Published: December 2011

The influences of alloying elements Mg, Zn and Cu and rare metals Ce, Er and mix rare metal (MRE) on the hydrogen content and inclusion in 1050 aluminum alloy were studied by optical microscope, scanning electronic microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results show that when adding 1wt.%Mg, 5wt.%Zn, 0.5wt.%Er and 0.5wt.%MRE into 1050 aluminum alloy, respectively, the decrements of density of the reduced pressure test (RPT) samples are 0.36g/cm3, 0.24g/cm3, 0.72g/cm3, and 0.24g/cm3, respectively. Mg and Er significantly increase the tendency of hydrogen adsorption in Al melt. The results of XRD analysis and microstructural observation indicate that the alloys adding Er contain more oxides and gas porosity.
Upgrade Silicon Powder Prepared by SHS with Acid Leaching Treatment
Authors: Liu Qing Sheng , Tang Hai Feng , Fang Hui
Published: December 2011

Upgrade silicon powder have been prepared by a two-stage technique consisting of a self-propagating high-temperature synthesis (SHS) process in a SiO2+Mg system in an inert atmosphere and the hydrometallurgical treatment of the combustion product. It was found from DTA curve that the initial starting temperature(Tin) of the reaction was 615°C. The adiabatic temperature (Tad) of system was calculated under the different molar ratios of Mg/SiO2 and the results showed the reaction would happen and be kept by the self-propagating way only when the excess coefficient(x) of Mg was more than 0.9. The value of Tad would increase with the increasing of x. XRD Pattern indicated MgO2 and element Si were main phases in combustion products except a little matter MgSi2O4. The purity of the combustion-synthesized Si samples was greater than 99.98% after the acid leaching treatment, and the experimental yield of the powder was approximately 78%.
Behavior of A356 Alloy in Semi-Solid State Produced by Mechanical Stirring
Authors: Nourouzi Salman , Kolahdooz Amin , Botkan Mohammad
Published: December 2011

This investigation studied semi-solid (SSM) aluminum-silicon alloy produced by mechanical stirring. Aluminum alloys produced by this method, are widely used instead of conventional die casting and forging processes. In this research by using a mechanical stirrer slurry maker, the effects of stirring speed, the solid fraction percent and mold temperature are investigated on micro-structure and hardness of A356 aluminum alloy in semi-solid casting. By optimizing the forming parameters, dendrite microstructure changes to globular and mechanical properties improves. This is because of breaking and globularizing dendrites of primary α-AL phase. It is determined that stirring temperature of 608°C and stirring speed of 300 RPM leads to the uniform grains distribution and therefore arrives to better hardness for the produced billets.
Corrosion Behavior of Pb-Ca-Sn Electrodes for Copper Electrowinning
Authors: Yuan Xue Tao , Lv Xu Dong , Hua Zhi Qiang , Wang Lei , Li Tao
Published: December 2011

Anodic polarization behavior of ternary alloy Pb-0.08%Ca-1%Sn is studied by potentiodynamic polarization measurements, corrosion rate, the products on electrode surface after polarization, and microstructure of anode mud after polarization in electrowinning cell. The results show that Pb-Ca-Sn anode is easy to be passivated in electrolyte for copper electrowinning, the maintaining passivity current density is 97.72 µA•cm-2and the corrosion products on the surface of Pb-Ca-Sn electrode present loose scaly, being composed of α-PbO2, β- PbO2and PbSO4after polarization.
Thermodynamics Analysis of Hot Metal Dephosphorization Flux Reaction Process
Authors: Ding Hui , Jin Yan , Tian Zhi Bing , Wu Dan Jiang
Published: December 2011

In this paper, CaO-Fe2O3-CaCl2and CaO-Fe3O4-CaCl2system dephosphorizer depho- -sphorization of the thermodynamics of the use of FactSage thermodynamic calculation software Equilib module of hot metal dephosphorization flux and the balance between the response calculated, to find the right dephosphorizer dephosphorization ratio and the conditions for optimal phosphorus removal. First of all, by the beginning of slag and the final calculated optical basicity slag and phosphate capacity, calculated on the balance FactSage software phosphorus content mapping, and comparative analysis. Followed by software at different temperatures to calculate the iron liquid, liquid slag, slag liquid solid phase of calcium phosphate and calcium phosphate and quality data on the thermodynamic equilibrium temperature mapping analysis..
Study of Metallurgical Industry Smoke Characteristics and the Affect to the Performance of Electrical Precipitator
Authors: Qi Li Qiang , Liu Jiang
Published: December 2011

Metallurgy industry is an important part of national economy, thereinto, steel enterprise is the most important part, and it has become a significant symbol of comprehensive national strength. According to the analysis, in the Large and medium-sized Steel enterprise the effect of energy saving and emission reduction is obvious, But the process equipment behind of small and medium-sized enterprises, high energy consumption and discharge many pollutants. In order to reach require, Electrical precipitator has been widely used. In this text, we make comprehensive narrative for metallurgy industry characteristics of flue gas, and analyze the affect of flue gas to electrical precipitator, finally, we put forward some constructive measures and suggests.
Numerical Simulation on the Influence of Heating with Different Arrangement of Burners on the High Performance Hydrogen Bell-Type Annealers
Authors: Fang Shun Li , Jin Shi Ping , Zhang Yong Xiang , Huang Su Yi , Wen Wu Qi , Zhou Yi Lin , Li Shi Bin , Zhu Da Jun
Published: December 2011

The heating bell with burners is an important heating device for the high performance hydrogen bell-type annealers. The arrangement of the burners has an important impact on the heating effect. In this study, we simulated a series of model with different location of burners under the same quantity of burners and the same heating power. The result shows: (1) Under the same quantity of burners and the same heating power, when we increase the number of rows of burners, the maximum temperature inside the furnace could be reduced, and the temperature distribution will become more uniform; (2)When we fixed the number of the row of the burners, if we move the upper burners to higher position to make the arrangement of burners more uniform, the temperature distribution inside the furnace will be more uniform, this will be good for the heat transfer to the higher parts of the annealers, and this will accelerate the heating process, improve the efficiency of annealing, reduce fuel consumption, and extend the life of the inner bell.
Combustion Performance and NO Emission in Industrial Furnace under Preheated Air Condition with Different Excess Air Ratio
Authors: Su Ya Xin , Wang Wen Hui
Published: December 2011

The effect of excess air ratio on combustion performance in an industrial furnace with a swirling burner was numerically modeled. The simulation was carried out at inlet oxygen fraction of 8% and a preheated air temperature of 1273 K for natural gas. The gas combustion process was calculated by a Beta function PDF (Probability Density Function) combustion model. The transportation of the turbulent flow in the furnace was modeled by Reynolds Stress Model (RSM). The radiation was simulated by a Discrete Ordinates method. The NO chemistry was simulated by thermal NO model. The effect of excess air ratio on NO emission, temperature, O2 and CO distribution in the furnace was investigated. Results showed that thermal NO emission increased from about 5 ppm to 70 ppm when the excess air ratio increased from 1.05 to 1.25. The burnout of natural gas was improved at increased excess air ratio, i.e., CO emission decreased. The maximum and average temperature in furnace did not change much at different excess air ratio. When the excess air ration is 1.1, both good burnout of fuel and low thermal NO emission (<15 ppm) were achieved.
Large-Scale Rotary Steam Tube Drying System and Equipment for Copper Powder
Authors: Wu Jing , Wang Hong Yao , Shi Yong Chun , Fan Hong Mei , Li Xiao Guang
Published: December 2011

Drying is a crucial step in the process of copper powder flash smelting for the direct influences on the quality of smelting. This paper proposes a unique system to match the special requirements of drying raw copper powder, such as large mass rate, small diameter dust and abrasion. On the bases of drying features and energy conservation, optimization design of drying system and equipment was also carried out. In site tests showed the satisfaction on working stability, energy thrift and quality of final product.
Prediction Model of Micum Strength for Iron Ore Sinter
Authors: Wang Wei , Xu Zhi Hui , Yang Long Long , Xue Zheng Liang , Zhao Dong Nan , Song Sheng Qiang
Published: December 2011

Micum strength is an important indicator of quality of sinter; BP artificial neural network model is built to predict the strength of sinter drum. The neural network use the main factors that influence the sinter drum as input data, and output is Micum strength. Experiment results shows that the maximum absolute error between the Micum strength predicted by neural network and real value from the sinter plant is 0.3346, and the average absolute error is 0.1154. These prove that the prediction is accuracy. In addition, because of the "black box" characteristic of the neural network model, the neural network model can not give the law of how the various factors affect the micum strength of sinter ore, this paper also uses the model to analysis the law of how TFe, SiO2 content affect the micum strength. The results not only consist with the sintering theory, but also verify the validity of the model.
The Research on Breakout Prevention by Logical Judgement
Authors: Sun Li Gen , Li Hui Rong , Zhu Li Guang
Published: December 2011

The breakout is one of the biggest problem in continuous casting. For the high failing and missing report rate of the system by indraught, whose report parameter cannot been changed, one new breakout prevention system which can optimize its parameters and based on the theory of the marked differences between temperature changing trend and spreading speed of the different temperature signal mode has been developed, it also has the hot distributing map. This system has a good running, and successfully reported all the breakout and defects of the slab.
Fixation of Thermocouple’s Site and Established Value in Course of Desorption of Gold-Loaded Carbon
Authors: Lin Guo Liang , Bai Jun Zhi , Lin Hai Yang , Chen Xiang Xiang
Published: December 2011

Based on industrial experiment and analysis of theoretical calculation, the paper shows that it will be always unsuitable for thermocouple to be fixed on any sites of the desorption column if the established value of temperature-controlling apparatus is just the same temperature as is required to desorption process. When the thermocouple is fixed on the bottom of the desorption column or on any sites of the heating apparatus, the heating apparatus will have to switch frequently. The result should also be avoided in production concerned. The site of the thermocouple and its established value can be only determined finally through industrial experiment and theoretical calculation since they are connected with many conditions necessary to the desorption operation.
Effect of Grinding Aids on the Fracture Energy of Mica
Authors: Wang Ze Hong , Yu Fu Jia , Cai Shan , Deng Shan Zhi , Horn Roger
Published: December 2011

An extension of the classical Obriemoff experiments has been set up to measure the fracture energy of mica. This experimental system will be entirely independent of slurry rheology. CTAB (Cetyl Trimethyl Ammonium Bromide), sodium tripolyphosphate, sodium hexametaphosphate, and tri-sodium citrate are used as grinding aids in this study and the fracture energy has been measured for mica in air, water, and water with the addition of various concentrations of these grinding aids. The results show that the fracture energy of mica in water is about half of what it is in air. Grinding aids are shown to reduce the fracture energy of mica, but not dramatically. Addition of grinding aids reduces the fracture energy by a further 10-20%, with tri-sodium citrate appearing to be the most effective. For each grinding aid there appears to be an optimal concentration, typically around 10 mmol. An experiment is also done with sodium chloride at a range of concentrations to investigate the mechanism of these grinding aids, but no reduction in fracture energy (compared to water) was observed, hence the molecular-level mechanism of action of these grinding aids remains unclear. The effect of solution pH values on the fracture energy are also investigated using tri-sodium citrate and sodium chloride. The results show that the solution pH value may effect on the fracture energy of mica. So, in practice, both concentration and pH value of solution are important for getting better grinding results.
Industry Test on Phosphorus Removal and Direct Reduction of High-Phosphorus Oolitic Hematite Ore
Authors: Li Yong Li , Sun Ti Chang , Kou Jue , Xu Cheng Yan , Liu Zhan Hua , Guo Qian
Published: December 2011

Industry test on phosphorus removal and direct reduction of the “Ningxiang type” high-phosphorus oolitic hematite ore has been carried out in a tunnel kiln on the basis of laboratory experiment. The iron grade and phosphorus content of the initial sample are 42.46% and 0.867%, respectively. The results showed that high-phosphorus oolitic hematite could be exploited on industrial scale, with the new process direct reduction roasting – grinding – magnetic separation, and that the final concentrate with an iron grade 92.56%, iron recovery 82.77% and phosphorus content 0.089% was obtained under the optimal conditions. Besides, X-ray diffraction (XRD) and scanning electron microscope with X-ray energy dispersive spectrum (SEM-EDS) were used to analysis the mechanism of phosphorus removal and direct reduction. It was shown that oolitic structure was destroyed, and metallic iron particle coarsening was obvious, besides fluorapatite particles were dispersed in the gangue by diffusion during the reduction roasting process. The liberation of metallic iron and gangue can be achieved by grinding, so high iron grade and low phosphorus content concentrate can be obtained after magnetic separation.
Dynamic Analysis of a Novel Structure of Dry Coal Separator
Authors: Li Jun , Wang Zhong Xian , Li Feng , Liu Chu Sheng
Published: December 2011

This paper presents a novel structure of the dry coal separator with vibration fluidized bed and analyzed the dynamic characteristics of the vibration parts. The natural frequency, natural mode of vibration and dynamic response are calculated based on the finite element method. The results show that the natural frequency is far from working frequency, so that the structure can avoid resonance frequency effectively. The maximum von Mises stress is 0.01MPa which are allowed in the working condition.
New Developments and Applications of Coal Mine Pressure and Force Monitoring Technology
Authors: Wang Qing Biao
Published: December 2011

Some new techniques used to improve the characteristics of vibrating-wire sensor and their applications in coal mine pressure and force monitoring are summarized. First, the new mathematical model and its applications are given. Second, the match of wire and diaphragm for the horizontal wire type sensor to reduce the hysteretic of the sensor is presented. Third, the weak excitation of the wire is stated which can effectively solve the problem of frequency variations. At last, the techniques of piston-conveying pressure and force conversion can be used to improve the accuracy and long-term stability, and to design the wide range、 high accuracy、high resolution and long-term stable pressure sensors and force sensors.
Experimental Study on Permeability Characteristics of Soft Coal under Higher Confining Pressure
Authors: Chen Shao Jie , Guo Wei Jia , Wang Hai Long , Sun Xi Zhen , Shi Jun Wei
Published: December 2011

In order to study permeability characteristics of low-strength coal under higher confining pressure, complete stress-strain permeability characteristics tests on 15# coal of Shanxi Province Qinshui Basin are conducted. Research shows that 15# coal manifests obvious plastic under 6MPa confining pressure whose uniaxial compressive strength is 7.43MPa; The saturated specimen’ permeability reduces provisionally during initial compression as the native fractures are closed; With the specimen compressed continuingly, new fractures appear and those fractures connect, then the permeability rapidly increase; But while the soft coal enters into plastic-flow state, because that the specimen becomes more homogeneous and fractures have closed, the permeability greatly reduces lower then the initial value. Research result has important guiding significance for reasonable retaining waterproof pillar in deep mining.
Research on Detoxifying Treatment to Chromium Slag
Authors: Shi Yu Min , Wang Tong , Hu Cheng , Bai Lin , Sui Zhi Tong
Published: December 2011

A particular industrial waste was selected as reducer for detoxified chromium slag in solid phase. Oxidation resisting was also tested. The results showed that concentration of Cr(Ⅵ)in the products was related to experimental condition, such as the proportion of chromium slag, the granularity of reactants, the reaction temperature and time . The leached Cr(Ⅵ)in the products was remained below 0.5 ppm of GB8978-1996 limits.
Rock Failure Mechanism of Air-Decked Smooth Blasting under Soft Interlayer
Authors: Wu Liang , Yu Dong Xiao , Duan Wei Dong , Zhong Dong Wang
Published: December 2011

In order to enhance smooth blasting adaptability and its effect in mining for rock mass complex characteristics, and based on the dynamic finite element analysis software with the material model of Mat-Plastic-Kinemetic, the dynamic stress characteristics and failure mechanism of blast-hole near-field with level soft interlayer are researched on different air-decked charge structures. The main effect of soft interlayer on top-air-decked charge structure is the tensile strength and range at the top of blasting hole, but the main effect of soft interlayer on middle-air-decked charge structure is the tensile strength and range at the middle of blasting hole, and some effect of soft interlayer on bottom-air-decked charge structure is the extension of rock crack at the bottom of blast- hole.
The Observation and Research for Morphology and Microstructure of Pyrite Whiskers Synthesized by Hydrothermal Process
Authors: Song Dan , Huang Fei , Chen Lin , Jia Dong Dong , Li Guang Lu , Lin Jia Lei , Li Jian Yuan , Gao Wenyuan
Published: December 2011

Morphology and micro-structure of the pyrite whiskers synthesized by hydrothermal process were systematically observed by using transmission electron microscope. The results indicated that whiskers revealed various morphologies, including smooth, rough and branched. Combined with the hydrothermal reaction conditions, the causes of whiskers morphology diversity is: straight smooth whiskers grow in the condition of stable concentration, temperature, and interface state; whiskers with rough surface and complex morphology grow in the condition of unstable concentration, temperature, and interface state; the same level branching structure rotation was the result of hydrothermal disturbance; nano-crystalline grains formed after the main growth of the whiskers.
Measurement and Analysis of Air Resistance on Baishan Coalmine
Authors: Cheng Gen Yin , Qi Ming Feng , Zhang Jing Gang , Wang Wen Yong , Wang Fang
Published: December 2011

The test on mine ventilation system resistance is an important task of coalmine safety production and ventilation safety management, and the size of the air resistance will affect ventilation directly. In view of the current situation of Baishan ventilation system, we selected 11 main test lines combined with practical application, to test on the ventilation system via adopting precision barometer of point test, by which we got a comprehensive result on the distribution condition of coalmine ventilation system. By analysizing results show as follows: the distribution of Baishan ventilation system resistance is basically reasonable, air quantity is able to meet actual production of the mine and the resistance centers in return airways. Finally, the author puts forward some rational suggestion for the stability of Baishan ventilation system.