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Zhao Q.-L.,North China University of Water Conservancy and Electric Power | Chen F.-J.,Yongcheng Vocational College | Wang Y.-Y.,North China University of Water Conservancy and Electric Power | Zhang B.-L.,Henan Agricultural University
Research Journal of Applied Sciences, Engineering and Technology | Year: 2013

The low bulk density of straw is one of the major barriers, which blocks the collection, handling, transportation and storage. Densification of biomass into briquettes/pellets is a suitable method of increasing the bulk density of biomass. Yet in the process, a tremendous amount of air is ejected from biomass grind, which brings substantial specific variation including combustion property. Among them, combustion property is critical for proper design and operation of burning facilities. Therefore, a series of tests about combustion properties of 75mm diameter corn briquettes were done. First, the combustion process (ignition, full flaming and glowing phases.), precipitation oftar were investigated by a heating stove, then, Some ash sample from the muffle burner was subjected to an ash melting characteristic test.The results show the combustion of briquettes takes more time than that of raw straw from ignition to complete combustion; in order to meet complete combustion in a short time, the raw straw needs more supply air volume than briquettes under the same α value; the temperatureof furnace chamber should been controlled under 900°C, which help to reduce the dark smoke, tar and slag. © Maxwell Scientific Organization, 2013.

Qing-Ling Z.,North China University of Water Conservancy and Electric Power | Fu-Jin C.,Yongcheng Vocational College | Yang-Yang W.,North China University of Water Conservancy and Electric Power | Bai-Liang Z.,Henan Agricultural University
Research Journal of Applied Sciences, Engineering and Technology | Year: 2013

In order to develop a mechanism of clean and efficient combustion, this study studied the combustion mechanism of stover semi-gasification by a clean stove designed. The experimental material was corn Stover briquettes. Process of semi-gasification combustion can be divided into two parts: gasification stage and combustion stage. First, under the low primary air amount, stover gives off partly combustible gas (Volatile matter). Then, the combustible gas rises and burns in the upper Furnace when it meets higher secondary air amount. At the same time, the residue remained in bottom Furnace keeps on gasifying and burning under high temperature until the fuel is exhausted. In the process, two phases (solid and gas) combustion becomes into one phase (gas) combustion. Due to inadequate primary air and low temperature of semi-gasification chamber (550-750°C), all the ash was loose and no slag was found. Moreover, combustible gas produced was directly completely burned off and no tar appeared in the emissions. According to the result, the combustion thermal efficiency of clean stove (75%) is up to 75% and higher than primary stove (below 12%). © Maxwell Scientific Organization, 2013.

Liu S.,Xijing University | Cai Y.,Yongcheng Vocational College | Li C.,Industry Engineering and Technology Center | Wu S.,Xijing University
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2015

According to the principle that self-pairing of the same metal could increase the friction coefficient, friction flow welding was conducted on 6061-T6 aluminum alloy by using improved pinless friction stirring tool. Tensile fracture mechanism of the weld was analyzed using macro-morphology analysis and tensile testing. The results show that embedding the material to be welded in form of bar into the friction stir tool can increase friction and adhesion between the friction stir tool and the workpiece, thereby increasing thickness of the plastic zone of the weld. The larger the diameter of the bar embedded into the friction stir tool, the higher the soldering temperature-increment rise rate. When diameter of the bar reaches 10 mm, tensile strength of the weld reach up to 250 MPa (86% of the base material), which is 1.8 times of the sample welded with ordinary friction stir tool. ©, 2015, Journal Office of Special Casting and Nonferrous Alloys. All right reserved.

Liu S.,Xijing University | Cai Y.,Yongcheng Vocational College | Wu S.,Xijing University
Jinshu Rechuli/Heat Treatment of Metals | Year: 2014

5083 aluminum alloy sheet was processed with several combined processes of warm rolling and annealing process. By use of tensile tests, influences of total rolling compression ratio and annealing process on elongation were analyzed. The results shows that maximum elongation of the 5083 aluminum alloy with total rolling compression ratio of 96.67% reaches 443% at 250°C with strain rate of 1 × 10-3s-1, which means that superplastic property is improved by increasing total compression ratio. Microstructure analysis shows that the more equiaxed fine grains of the specimens the better superplasticity. On the basis of the optimum processing, elongation of the samples prepared with simplified processing by shorten annealing time also reaches 350%, which contributes to improving efficiency.

Sheng S.X.,Xijing University | Guo Y.L.,Yongcheng Vocational College | Liu S.F.,Xijing University | Wu S.L.,Xijing University
Advanced Materials Research | Year: 2014

In this research, one solid state processing technique, friction stir processing, is applied to modify the AZ61 magnesium alloy billet. The FSP modified AZ61 alloy could be refined to 3-8 μm via the dynamic recrystallization during processing. The AZ61 magnesium alloy billet with 75μm grain size could be refined to about 7.5μm by four-pass friction stir processing. The hardness of the stirred zone could increase to around 70-80 after friction stir processing, and after a further compressive strain of about 3% could raise the hardness to 81. The ductility of the weld direction specimens of the modified alloy could have a 235% elongation at 300°C and 1×10-4 s-1. The grain boundary sliding (GBS) might be the dominant deformation mechanism during superplastic deformation. © (2014) Trans Tech Publications, Switzerland.

Liu S.-F.,Xijing University | Cai Y.,Yongcheng Vocational College | Wu S.-L.,Xijing University
Advanced Materials Research | Year: 2014

5083 aluminum alloy was processed with combined process of warm rolling and annealing. Elongation and tensile strength of samples were measured to analyze the influences of annealing temperature and annealing time on its mechanical properties. Results show that low temperature superplasticity is very sensitive to temperature. The maximum elongation for 5083 aluminum alloy reaches 443% at 250°C and a strain rate of 1×10-3s-1, which means that 5083 aluminum alloy exhibits excellent low temperature superplasticity. Low temperature annealing before drawing could not effectively improve the elongation. © (2014) Trans Tech Publications, Switzerland.

Liu S.-F.,Xijing University | Xue F.,Yongcheng Vocational College | Wu S.-L.,Xijing University
Advanced Materials Research | Year: 2014

This study is aimed to investigate the spring-back angle of clad metal sheet in bending process by using finite element simulation and experiment to meet the growing requires in the application of clad metals. In this study, the clad metals processed into 1mm thick from CU11000 and AL1050 were bent 90°C over a die with a bend radius of 1mm. The results show that there is not any relative sliding, crushing or peeling occurred in the junction of the clad material during the bending process, the spring-back angle of the clad metal is always smaller than each single metal and the CU content increasing also caused spring-back angle become small. The configuration of a harder material (CU11000) in tensile side also has a smaller spring-back angle. © (2014) Trans Tech Publications, Switzerland.

Wang T.,Henan Institute of Science and Technology | Zhang Y.,Yangzhou University | Ding T.,Yongcheng Vocational College
Materials Letters | Year: 2014

A one-step in situ solvothermal method was proposed for the synthesis of SnIn4S8/TiO2 nanocomposite with 6.5 mol% SnIn4S8, using SnCl4·5H2O, InCl3·4H2O, thiourea, tetrabutyl titanate and absolute ethanol as the source materials. The structure, composition, BET specific surface area and optical property of the as-synthesized SnIn 4S8/TiO2 nanocomposite were characterized by powder X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning electron microscopy, N2 adsorption and UV-vis diffuse reflectance spectra. The photocatalytic activity of the as-synthesized SnIn 4S8/TiO2 nanocomposite was tested in the reduction of aqueous Cr(VI) under visible-light (λ>420 nm) irradiation, and compared with those of nanostructured SnIn4S 8 and TiO2. The photocatalytic results demonstrated that the as-synthesized SnIn4S8/TiO2 nanocomposite exhibited much higher visible-light-activated photocatalytic activity than SnIn4S8 and TiO2 nanoparticles. The reasons accounting for the photocatalytic results were also discussed. © 2014 Elsevier B.V.

Yan Z.,Henan University of Science and Technology | Wang D.,Yongcheng Vocational College | Huang J.,Henan University of Science and Technology | Gu Y.,Henan University of Science and Technology | Zhang Y.,Henan University of Science and Technology
Yadian Yu Shengguang/Piezoelectrics and Acoustooptics | Year: 2013

The sintering characteristics, microwave dielectric properties, phases and microstructure of Cu-doped ZnTiNb2O8 ceramics prepared by solid-state reaction method have been investigated systematically. It was found that the addition of Cu powder lowered the sintering temperature of ZnTiNb2O8 ceramics to 950°C. The results showed that the microwave dielectric properties of Cu-doped ZnTiNb2O8 ceramics were strongly dependent on densification, crystalline phases and grain size. The specimen with 3.0wt% of Cu powder additive sintered at 950°C for 3 h possessed an excellent combination of microwave dielectric properties: εr=30.2, Q×f=27537 GHz (f=6.7743 GHz), τf=-57.1 μ°C-1. Due to their good dielectric properties, the Cu-doped ZnTiNb2O8 ceramics are very promising candidate for LTCC dielectric materials.

Han W.-J.,Yongcheng Vocational College | Zhang P.-X.,Yongcheng Vocational College | Tang Q.-J.,Yongcheng Vocational College | Song J.-C.,Yongcheng Vocational College
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

Combining with the characteristics of the special environmental conditions in mining, taked the sample-the hydraulic support which was made of 27SiMn steel used in coal mines as the matrixbase, and analyzed the cladding layer which was cladded with Ni60A+20%WC alloy powder using laser. Microstructure and properties of the cladding layers were examined by means of SEM, hardness test, wear testand salt-mist test. The results show that metallurgy binding interface between the cladding layer and the base metal is obtained. Wear-resistance and hardness of the clad 27SiMn steel are obviously improved. The cladding layer has high hardness and strong corrosion resistance.

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