Abstract: Construction of the pavement has consumed a huge amount of high grade aggregates, such as basalt, limestone etc. In some region, these aggregates are very scarce and have to be produced and transported from far aggregate quarries which would cause the waste of energy and resources as well as the increase of cost. Large quantities of gneiss exist in China, the use of gneiss as aggregates might help meet the highway constructing demands and save. In this paper, the feasibility is analyzed with respect to different aspects. Physical properties of gneiss aggregate were evaluated using Los Angeles abrasion, specific gravity and flakiness index. Mixture properties were characterized in terms of Marshall stability, moisture susceptibility, soak wheel track and low temperature cracking resistance property. Experiment results indicate that the physical properties of gneiss aggregates can satisfy the related specifications and these gneiss materials as aggregates can be used in asphalt pavement. Results also show that the optimal gradation component of the mixture consists of the gneiss as coarse aggregate and the limestone as fine aggregate. The use of hydrated lime can improve the moisture susceptibility of the mixtures containing gneiss aggregates.
Abstract: In this paper, fluorine & antimony-doped tin oxide (FATO) transparent conductive thin films are deposited by Spray Pyrolysis on glass substrate, and low emissivity properties achieved. The emissivity of glass in far infrared region is optimized by changing the spray volume, the resistivity and sheet resistance of thin films. Research shows that the resistivity of thin films has important influence on infrared reflectance and hemispheric emissivity. This paper further investigates the quantitative relationship between emissivity and resistivity of low-E glass and also provides a basis for emissivity control and performance evaluation of Low-E glass.
Abstract: The most attractive way to storage hydrogen safely and economically is in metal hydrides. In particular, magnesium has attracted much interest since their hydrogen capacity exceeds that of known metal hydrides. One of the approaches to improve the kinetic is addition of metal oxide. In this paper, we tried to improve the hydrogen absorption properties of Mg. The effect of transition oxides, such as Nb2O5 on the kinetics of the Mg hydrogen absorption reaction was investigated. MgHx-Nb2O5 composites have been synthesized by hydrogen induced mechanical alloying. The powder synthesized was characterized by XRD, SEM, EDX, BET and simultaneous TG/DSC analysis. The hydrogenation behaviors were evaluated by using an automatic Sievert’s type PCT apparatus. Absorption/desorption kinetics and PCI of MgHx catalyzed with 5wt.%Nb2O5(as-received), 5wt.%Nb2O5(30min. milled) are determined at 423, 473, 523, 573, 623K.
Abstract: Many laboratories have researched membrane for gasification of coal technique, separating hydrogen from fossil fuel. In general, Pd membrane of separating hydrogen is very good a property of hydrogen selectivity on high temperature, but it has some problems, hydrogen embrittlement and costly material. So, we need some materials of good properties about hydrogen selectivity instead of Pd. In this research, we fabricate membrane for hydrogen permeation, that is great in resistance to acids and chemically steady TiN. Our laboratory investigated about hydrogen selectivity. TiN powder is milled 30, 60 and 240 minutes by vibration mill, respectively. After than the samples put in operate spark plasma sintering. We analyze XRD, SEM, BET and TG/DSC. Also, in this research take an inspect hydrogen selectivity by ourselves manufactured Sievert’s type hydrogen permeation membrane equipment.
Abstract: Li2MSiO4(M=Mn, Co, Ni) is a potential high capacity cathode material because of its outstanding properties that exchange of two electrons per transition metal atom is possible and the theoretical capacity of Li2MSiO4 can reach as high as 330 mAhg-1. In this family, the cathode performance of Li2MnSiO4 synthesized by solution route has been published recently. However, it seems that the cycle life of Li2MnSiO4 fell short of our expectation. In this work, the Li2Mn0.7Fe0.3SiO4 cathode material was synthesized by traditional solid-state reaction method. The prepared powder was consisted of majority of Li2Mn0.7Fe0.3SiO4 and minor impurities which were examined by XRD. FESEM morphology showed that the products of Li2Mn0.7Fe0.3SiO4 and Li2MnSiO4 have similar particle size (about 50-300 nm). The electrochemical performance of Li2Mn0.7Fe0.3SiO4, especially for reversible capacity and cycle life, exhibited better than those of Li2MnSiO4.
Abstract: With practical data of the BF ironmaking from Jiuquan Iron&Steel Cooperation Ltd. (JISC), taking the quality of pig iron as evaluation indicator, mathematical models based on the least square regression and partial least square regression were set up respectively by co-relation analysis of feeding-to-product interval of the BF processing. The calculation results showed that the reasonable description can be obtained by the partial least square regression model; and 10 of 29 parameters with obvious impact on the BF operation were listed accordingly. Meanwhile, an optimal group of parameters was found by genetic algorism calculation method. The optimal index of the group was 99.13％. This study is beneficial to the improvement of feeding adjustment and optimal operation of BF ironmaking.
Abstract: The purpose of this work was hydrogen permeation of ceramic or metal/ceramic membrane using γ-Al2O3 by synthesizing. The γ-Al2O3 was synthesized by using the sol-gel process with aluminum isopropoxide and primary distilled water as the precursor and solvent. The γ-Al2O3-based membranes were prepared using HPS. The phase transformation, thermal evolution, surface are and morphology of γ-Al2O3 and γ-Al2O3-based membranes were characterized by XRD, TG-DTA, BET and FE-SEM. The hydrogen permeation of γ-Al2O3-based membranes was examined at room temperature comparing with other paper using nickel composited membrane on alumina ceramic support.
Abstract: The porous TiO2 layer on the silicon surface not only acts as a buffer layer to relieve the strain associated with the volume expansion but also prevents the aggregation of the particles upon normal cycles of charging and discharging. The control of the optimum amount of catalyst has led to enhance the cycle performance of TiO2 coated silicon anode.
Abstract: In this paper, cordierite-mullite multiphase ceramics material was prepared using cordierite powder, mullite particles, fused silica, magnesia and alumina as main starting material. Effects of addition of 2%~10% SiC on the thermal expansion, flexural strength and thermal shock resistance were studied, and the fracture surface morphology was observed with Scanning Electron Microscope (SEM). The results showed that the multiphase ceramics material’s thermal expansion coefficient and flexural strength had little change. The thermal shock resistance of cordierite-mullite multiphase ceramics material varied as increasing-decreasing with the increase of SiC content, when the content of SiC was as high as 4%, the highest conservation rate of the flexural strength after 1100°C~water(3 times) was 72.08%, and the thermal shock resistance of cordierite-mullite multiphase ceramics material was superior.