Advanced Materials Research Vols. 881-883

Abstract: The chloride ion concentration of sea sand were measured by Volhard method and identified the method of removal chloride ions in sea sand. By comparison of compression test for sea sand concrete and river sand concrete ,two compressive strength performance is basically the same , Verify the feasibility of the concrete of the treated sea sand for bluiding.

Abstract: CBM well pattern optimization is the key issue for CBM development. Usually the selection of well pattern is a problem to coordinate the cumulative productivity and recovery. For finding the optical well spacing, this article will coordinate the two parameters after they are transformed into dimensionless form. And the economic research for the optimal well spacing is adopted as a supplemented proof. Finally the CBM well pattern of the block in North Qinshui basin must be a square well pattern the 300m×300m is regarded as the optimal well spacing.

Abstract: In this paper, ways of heat transfer through windows and doors between the indoor and outdoor environment in the northern area are summarized. And every heat transfer way is described by mathematical formula. On this basis, methods to improve the energy saving performance of exterior windows are put forward according to factors affecting heat transfer through windows. The first method is increasing solar radiation heat, and then reducing heat loss by infiltration, and increasing the thermal resistance as much as possible. Ideal form of energy-saving window is proposed based on compared windows with different material and thermal resistance.

Abstract: Adsorption-desorption behavior of a novel humidity control paperboard was investigated on the conditions of different pretreatments and variable amounts of usage. The results revealed that the target humidity varied because of different moisture contents. In addition, the target relative humidity was about 50% with the moisture content being about 20%. The humidity control performance of the paperboard could be measured with initial 80% of relative humidity. The dosage ratio of sample to container is 1g/L. On the condition that the moisture content was 20%, when the usage ratio was less than 1, the target relative humidity decreased with the increasing ratio. Yet the target humidity of micro-environment changed little and the adsorption-desorption rate varied dramatically. Knowing the humidity control behavior of the composite paperboard is important for its application.

Abstract: The quantitative phase analyses of a slag have been successfully carried out by using both of the full-profile Rietveld and RIR methods from X-ray powder diffraction data. The qualitative phase analysis indicates that the slag contains mayenite (CaO)₁₂(Al₂O₃)₇, olivine Ca₂(SiO₄), gehlenite Ca₂Al (AlSiO₇), lemite Ca₂(SiO₄) and hibonite CaO(Al₂O₃)₆. The quantitative analysis from Rietveld refinement shows that the weight concentrations of mayenite, olivine, gehlenite, lemite and hibonite for the slag are 48.8(4) wt.%, 32.2(5) wt.%, 11.0(9) wt.%, 6.2(1.1) wt.% and 1.8 (1.2) wt.%, respectively. The quantitative phase analysis results obtained by Rietveld method are more precise then those by RIR method.

Abstract: Abstract .Electromagnetic radiation affects normal operation of electronic devices and causes harm to human health, the use of electromagnetic radiation protective material, especially the electromagnetic wave absorption material, is an effective method for interference control and radiation protection, λ / 4 type dielectric absorber with a simple and practical nature, the protective layer should be added to ensure its durability in practice, this article discusses the gypsum board as the substrate, the thickness of conventional protective layer's material impacts on the absorbing properties. Studies show that: the position of absorption peak moves to lower frequency with increase of the protective layer's thickness by the theory and experiment, this paper puts forward the protective layer's thickness criterion's impact on the absorption characteristics, the thickness less than 0.05 cm has little effect on absorption characteristics in S band , which can simplify theoretical calculation and be convenient to select a material; when the thickness of the protective layer has a significant effect on absorption, the relationship among the parameters of absorber can be found according to theoretical simulation, thereby reducing or eliminating the impact of protective layer thickness on absorption characteristics.

Abstract: The raw fly-ash applied in this study has an ignition loss of 17.30 %. The results of floatation experiment show 4.40 % coal content of tailing ash. The screen analysis results on decarburized fly ash shows that the content of +45 μm is above 12 %, failing to meet the quality of Grade I fly ash determined in the standard of China. Therefore, the decarburized fly ash was processed by grinding to meet the required quality. The analysis of the main constituents of different grinding methods conducted for tail fly ash shows that fly ash obtained by open circuit ball mill are the most suitable one used as admixture of concrete. Comparisons were made on the compressive strength and bending strength of 7d and 28d under the conditions of non-grinding and five ways of grinding. The test results show that grinding can improve the compressive strength of fly ash concrete. By way of closed-circuit grinding rod mill, concrete, can fly ash concrete strength be increased remarkablely.

Abstract: This paper deals with contact to carry on tension, bend, impact toughnesss stretch and the inclined Y type ascent experiments of the Hardox400 high strength steels welding. It research weld, fusion zone and heat affected zones micro organization of Hardox400 high strength steel in making use of the optical microscope, and prepare hot temperature, weld hot importation and empress hot temperature influence weld strength, bend and impact toughness, and the weld craft parameter can be assured under physically produces condition.

Abstract: The duplex stainless steel has better pitting corrosion resistance but lacks of hardness and wear resistance. Therefore, the low temperature nitriding treatment can be used to increase its hardness and wear resistance or to gain more perfect corrosion resistance. The plasma nitriding of SS2205 stainless steel was carried out at temperatures from 693k to 753k for 4 hours at anodic potential. The nitrided samples were analyzed by optical microscopy, X-ray diffraction, SEM-EDX analysis, microhardness testing, wear and corrosion evaluation. The XRD analysis of all treated samples showed that the nitrogen-expanded austenite phase was formed. Both α and γ phase of the substrate were transformed into γ_N during plasma nitriding. Observing the nitrided layers formed on α and γ phase, the ones situated in the austenite were thinner than the ones in the ferrite. This phenomenon was more evident at low temperature, which confirmed that the nitrogen has a higher diffusion rate in the ferrite during plasma nitriding treatment. The surface hardness of nitrided layer was increased with the nitriding temperature. The highest hardness value obtained in this experiment was about 1300 HV_0.05 which was 4 times as the original sample (380 HV_0.05). Furthermore, through the wear and corrosion property tests, it was shown that anodic plasma nitriding improved the wear resistance and corrosion resistance of the duplex stainless steel.

Abstract: This paper presents a conclusion drawn by adopting laser processing technology to form striated non-smooth surface of nodular cast iron and study the factors that affect the wear resistance at the normal temperature by means of single factor testing and orthogonal testing. It shows that the optimal conditions of wear resistance are 3-min (wear period),0.98mm (grid space), and 200 r·min^-1 (otary velocity).