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The combined blowing process of metallurgical multiphase reactor was simulated by water modeling. The effects of operation conditions on dispersed phase size distribution were studied and an empirical formula was obtained. Based on the law of additive codimensions, the interface areas under different operation conditions were calculated by means of box counting and projection relationship. The results show that the frequency of dispersed phase with certain granularity level are in a certain proportion to its size level, and the dispersed phase areas are influenced by the top and bottom combined blowing.

In this paper, Nd:YAG ceramic was prepared by combustion synthesis with centrifugation casting. Combustion temperature and pressure were calculated under adiabatic hypothesis, and measured experimentally by W/Re thermocouple and piezometer, respectively. The combustion temperature and pressure decreased with increase of the content of diluents (Y2O3and A12O3). The YAG could be obtained as the ratio between the Y2O3and A12O3reached 3:5. Phase composition and microstructures of the derived products were analyzed by XRD, SEM and EDS. The results show that the other reaction product TiN and a small quantity of gas and oxide impurity were not completely separated from YAG melt under centrifugal force so that transparent YAG ceramic was not obtained in this work.

Architects’ response on geographical culture has become an innovation of long-span building design, though it has always been overlooked by designers. This paper analyzes and discusses the connotation of regionalism and its importance on the configuration of long-span buildings. In addition, it summarizes and compares examples concerning natural and cultural factors of regional condition. In this way, this paper concludes that the exploration of local nature and humanity, and the communication of the inner spirits of regional culture are the main directions of the innovation and regional expression of long-span architecture.

The valve plate of the hot blast valve is to rely on itself spiral waterway to cool. In the course of actual use, there is uneven actuality that it is cold and hot for the Valve plate of the hot blast valve. In this article, by means of COSMOSFloworks software, based on classic formula for convective heat transfer of heat transfer, we do flow field analysis for the waterway of the valve plate of DN1800 hot blast valve for certain Heavy Industry Group of our country. And analytical result indicates: Uneven distribution of water velocity in the valve plate is an important reason for causing unequal heat exchange of the valve plate and local thermal shock. In order to improve cooling uniformity, the central flow state of the type valve Plate should be altered and water cooling structure of inner water ring edge should be widen, finally the increase of the life of the valve plate can be reached.

Tilting torque of mixed iron car is an important parameter in designing tilting mechanism. In the past, calculating tilting torque of the mixed iron car mostly depended on manual calculation with low calculating speed and calculating precision. This paper adopts Solidworks software to simulate and calculate tilting torque of the 300t mixed iron car, and overcome the above drawbacks. According to the calculating, the tilting torque’s curve can be obtained, which provides a theoretical reference for determining power of tilting motor, designing tilting mechanism and judging the tilting safety.

In order to find substrate specificity and enantioselectivity of ketoreductase domain (EryKR1) in the first module of polyketide synthase from Saccharopolyspora erythraea, the whole cells of recombinant Escherichia coli BL21 (pET-eryKR1)2 harboring eryKR1 gene fermented with different kinds of cyclohexanone derivatives such as methylcyclohexanone and cyclohexanedione. Gas Chromatography (GC) or Gas Chromatography Mass Spectrum (GC-MS) analyses of these ferments indicate that when the recombinant cells were employed as biocatalysts, only one carbonyl of 1,2-cyclohexanedione and 1,4-cyclohexanedione could be reduced with the conversion rate 20.44% and 6.03%, respectively. In addition, 2-methylcyclohexanone and 3-methylcyclohexanone except 4-methylcyclohexanone could be significantly turned over by the recombinant cells to their corresponding cis-methylcyclohexanols, of which the conversion rate of 40 mM 2-methylcyclohexanone was 12.2% and enantiomeric excess of cis-2-methylcyclohexanol was 57.98%, and the conversion rate of 10 mM 3-methylcyclohexanone was 38.26% and enantiomeric excess of cis-3-methylcyclohexanol was 53.9%. Furthermore, the unexpected reduction of 1,2-cyclohexanedione and 2-chlorocyclohexanone by the control E.coli BL21 (pET-28a) reveals that the attracting electron effect induced by the carbonyl or chlorin group in their ortho position could make some NAD(P)H-dependent oxo-reductase except EryKR1 domain within the recombinants reduce the carbonyl of 1,2-cyclohexanedione and 2-chlorocyclohexanone. Therefore, it is concluded that 1,4-cyclohexanedione, 2-methylcyclohexanone and 3-methylcyclohexanone except 1,3-cyclohexanedione and 4-methylcyclohexanone are accepted substrates of EryKR1 domain which takes on a certain biocatalyst activity and stereospecificity.

In this paper, an image de-noising algorithm based on the Dual-Tree Complex Wavelet Transform (DT-CWT) is proposed, which takes the advantage of redundant coefficients transformed by DT-CWT. The model of bivariate shrinkage function is used to provide a nonlinear threshold strategy. It exploits the dependency between inter-scale parents and children coefficients to recover the original coefficients more accurate. With the shift-invariance property of DT-CWT coefficients, the algorithm prevents the Gibbs effect caused by the thresholding, which further improves the reconstructed quality. Experiment results show that the de-noised image using DT-CWT can achieve more than 1dB prior to DWT with impressive visual results.

In order to make full use of small current grounding system transient information and to improve the accuracy of fault line selection, a method based on wavelet transformation was proposed. On the basis of wavelets transformation theory and its characteristics, a proper wavelet function was chosen up to take wavelet transform to collected fault data, and then to get the fault line according to the modulus maxima theory. The MATLAB simulation results show the effectiveness of the proposed techniques on improving the accuracy of fault line selection.

To assess the soil heavy metal pollution, there are so many methods, such as the mono pollution-factor, the comprehensive Nemerow pollution-factor and so on. Grey Relational Analysis (GRA) is one of the major contents of gray system theory. The method of GRA was used in the application of environmental impact assessment, such as water pollution research. In this paper, we designed the new practical method of the heavy metal pollution evaluation, which is focus on six soil heavy metals (Cd, Hg, Pb, Cr, Cu, Zn). According to the consenting range of environment level by the National Environmental Standard (GB15618-1995), we have done our researches.

According to the fast increase of Information data and continuous enhancement of people’s requirement for analyze of information, it is more and more difficult to get requisite information to judgment and decision-making. For solving these problems, the design of an intelligent forecast system based on back propagation neural network is introduced. And the framework, data processing and arithmetic of the system are presented. By continuously running program debugging and optimization settings to modify the parameters, the predicted results and actual test results is to be closer.

During the process of cultivation of salt-tolerant nitrifying bacteria, the increase in NaCl concentrations was carried out in two different manners. The NaCl concentration in reactor A was increased by increment of 5 g/L, while the NaCl concentration in reactor B was increased by increment of 2.5 g/L. The impacts of NaCl content on the fresh culture and two acclimated cultures were investigated, which focused upon the changes of the specific ammonium oxidation rate (SAOR) and specific nitrite oxidation rate (SNOR). The results indicated that fresh nitrifiers were severely inhibited by high salinity. At NaCl concentration of 25 g/L, ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) completely lost the nitrification capability. After 46 days of acclimation, the nitrifying bacteria could be adapted to the saline wastewater. The average SAOR and SNOR in reactor B were slightly higher than those in reactor A, which meant that low increment in salt concentration may be in favor of the development of salt-tolerant nitrifiers. But the two NaCl increasing approaches did not affect the SAOR and SNOR too much. Salt-tolerant nitrifiers could be well developed with the two acclimation manners.