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A new Mg–10%Al–1%Zn–1%Si alloy with non-dendritic microstructure was prepared by strain induced melt activation (SIMA) process. The effect of compression ratio on the evolution of semisolid microstructure of the experimental alloy was investigated. The results indicate that the average size of α-Mg grains decreases and spheroidizing tendency becomes more obvious with the compression ratios increasing from 0 to 40%. In addition, the eutectic Mg2Si phase in the Mg–10%Al–1%Zn–1%Si alloy transforms completely from the initial fishbone shape to globular shape by SIMA process. With the increasing of compression ratio, the morphology and average size of Mg2Si phases do not change obviously. The morphology modification mechanism of Mg2Si phase in Mg–10%Al–1%Zn– 1%Si alloy by SIMA process was also studied.

OBJECTIVE: To study the efficacy of early treatment via fiber bronchoscope in children with Mycoplasma pneumoniae pneumonia (MPP) complicated by airway mucus obstruction. METHODS: According to the time from admission to the treatment via fiber bronchoscope, the children with MPP who were found to have airway mucus obstruction under a fiber bronchoscope were randomly divided into early intervention group (≤ 3 days; n=40) and late intervention group (>3 days; n=56). The two groups were compared in terms of clinical data and imaging recovery.The children were followed for 1-3 months. RESULTS: Of the 96 children, 38 were found to have the formation of plastic bronchial tree, among whom 10 were in the early intervention group and 28 were in the late intervention group (P=0.01). Compared with the late intervention group, the early intervention group had a shorter duration of fever, length of hospital stay, and time to the recovery of white blood cell count and C-reactive protein (P < 0.05), as well as a higher atelectasis resolution rate (P < 0.05). Compared with the late intervention group, the early intervention group had a higher percentage of children with a ≥ 60% absorbed area of pulmonary consolidation at discharge. After 3 months of follow-up, the early intervention group had a higher percentage of children with a ≥ 90% absorbed area of pulmonary consolidation than the late intervention group (80% vs 55%; P=0.01), and the early intervention group had a lower incidence rate of atelectasis than the late intervention group (P < 0.05). CONCLUSIONS: Early treatment via fiber bronchoscope can shorten the course of the disease and reduce complications and sequelae in MPP children with airway mucus obstruction.

A Mg–14.28Gd–2.44Zn–0.54Zr (mass fraction, %) alloy was prepared by conventional ingot metallurgy (I/M). The microstructure differences in as-cast and solution-treated alloys were investigated. Sliding tribological behaviors of the as-cast and solution-treated alloys were investigated under oil lubricant condition by pin-on-disc configuration. The wear loss and friction coefficients were measured at a load of 40 N and sliding speeds of 30–300 mm/s with a sliding distance of 5000 m at room temperature. The results show that the as-cast alloy is mainly composed of α-Mg solid solution, the lamellar 14H-type long period stacking ordered (LPSO) structure within matrix, and β-[(Mg,Zn)3Gd] phase. However, most of the β-phase transforms to X-phase with 14H-type LPSO structure after solution heat treatment at 773 K for 35 h (T4). The solution-treated alloy presents low wear-resistance, because the hard β-phase is converted into thermally-stable, ductile and soft X-Mg12GdZn phase with LPSO structure in the alloy.

Large gantry machining centers are used for machining of products in almost all industry. To raise the design and production efficiency of machining centers, an integrated method of fast design and analysis is proposed in this paper. Firstly, large components unit structures are decomposed and extracted based on functions and structures. Then, after conducting fast analysis using APDL programming, a method of Comprehensive Evaluation is employed to optimal select the design schemes. Finally, the column of large gantry machining center QLMT6300 is taken as example to illustrate the validity of the method presented.

The sliding friction and wear behaviors of Mg–11Y–5Gd–2Zn–0.5Zr (wt%) alloy were investigated under oil lubricant condition by pin-on-disk configuration with a constant sliding distance of 1,000 m in the temperature range of 25–200 °C. Results indicate that the volumetric wear rates and average friction coefficients decrease with the increase of sliding speeds, and increase with the increase of test temperature below 150 °C. The hard and thermally stable Mg12(Y,Gd)Zn phase with long-period stacking order structure in the alloy presents significant wear resistance. The wear mechanism below 100 °C is abrasive wear as a result of plastic extrusion deformation. The corporate effects of severe abrasive, oxidative, and delaminating wear result in the tribological mechanism above 100 °C.

Cross-border mergers and acquisitions process are complex organizational behavior of complex organizations. The existence of cultural barriers, technical barriers, organizational barriers and knowledge distance would affect directly or indirectly absorptive capacity in cross-border M&As, thus affect the performance of knowledge transfer and M&AS strategy. Under the cross-cultural, cross-organizational, cross-environmental background, it is critical to analyze objectively and systematically absorptive capacity status in cross-border M&AS. Absorptive capacity in cross-border M&AS is divided into latent absorptive capacity and actual absorptive capacity in the research. The essence of exaltation mechanism of absorptive capacity is a sort of complex dynamic process that enterprises employ the way of organizational learning to polymerize and couple the knowledge elements of M&AS. As the analysis and research methods on dynamic complexity of system, SD (system dynamic) could integrate organically qualitative and quantitative methods to employ computer simulation technique to construct simulation model to analyze systematically the evolution process and exaltation path, so as to find the discipline of formation and exaltation of absorptive capacity.

A Mg-8%Al-1%Si alloy with semisolid microstructure was fabricated by isothermal heat treatment process. The effects of isothermal process parameters such as holding temperature and holding time on the microstructure of Mg-8%Al-1%Si alloy were investigated. The results show that a non-dendritic microstructure could be obtained by isothermal heat treatment. With increasing holding temperature from 560 to 575 °C or holding time from 5 to 30 min, the liquid volume fraction increases, the average size of α-Mg grains grows larger and globular tendency becomes more obvious. In addition, the Mg2Si phase transforms from Chinese script shape to granule shape. The morphology modification mechanisium of Mg2Si phase in Mg-8%Al-1%Si alloy during the semisolid isothermal heat treatment was also studied.

The overall effect of sealing the packaging has a very important role. Sealed plastic containers divided into four main ways, namely the bundle sealing, adhesive sealing, physical sealing and filling and sealing. They have their own characteristics. Bundling seal means the product can not be sealed, but its use is very wide, has a high degree of freedom. Low adhesive strength of adhesive sealing, but it is widely used. More complex structure of the physical sealing, but it has a wide variety of functions. Used in the filling and sealing gaskets are susceptible to damage, but it has a good seal. This paper analyzes the principles of their seal，which allows you to choose different sealing materials and the corresponding sealing structure to meet a variety of packaging needs.

Studied the vibration performance of honeycomb paperboard with double cross-core, obtained vibration transmissibility curve of honeycomb paperboard with double cross-core, by the curve indicated, the vibration transmission properties of the honeycomb paperboard with double cross-core in the sinusoidal excitation ,and the packaging materials as contents when the size of the protection capacity. The results show that the shock resistance capacity of honeycomb paperboard with double cross-core is supers the single layer with the same thickness of.

This paper measured the vibration transmissibility of several honeycomb paperboards and the attenuation coefficient. Laboratory was used to determine the natural frequency of the thickness of 10mm, 20mm, 30mm, 40mm Honeycomb Paperboard. The test results show that the honeycomb paperboard resonance frequency decreases with increasing thickness, while the vibration transmissibility increases with increasing thickness. We have also established finite element model of honeycomb paperboard to simulate its vibration properties. The result of simulation is in good coincidence with the experimental result. In addition, some cases can use computer simulation instead of laboratory testing to obtain the natural frequencies of honeycomb paperboard.

The residual stress fields can have strong influences on the integrity and performance of friction stir welded aluminum alloy structure, comprehensive insight into the residual stress distribution is the key to the Friction stir welding (FSW) engineering application for a wide range of materials and thicknesses improving the weld strength and fatigue life. In this paper, the current state of the residual stresses in the FSW aluminum alloy joints is reviewed, The focus is on recent advances of experimental research, the results of numerical simulation analysis, and the effects of the technological parameters(welding speed, rotational speed, shoulder geometry et al.) on residual stress fields was evaluated. In the end, The controlling technique of residual stresses from published literatures is summarized.

Operational Risk management is an important part of risk management. Facing to today's increasingly frequent operational risk of commercial banks, commercial banks need to develop practical operational risk control procedures and relevant measures, The establishment of Early-warning systems of operational risk would play a very important role in the future risk management. By means of the BP Neural Network analysis and nonlinear model methods, the paper would analyze and resolve the nonlinear relationship between several Key Risk Indicators (KRI) factors of commercial banks operational risk and risk results. According to establish the Early-warning system model of operational risk management for commercial banks, the paper expect that the research could provide some important references to prevent and control effectively operational risk for commercial banks.

Credal network is the extension of Bayesian network. It could not only introduce the uncertainty into the probability sets but also integrate various knowledge and opinion of financial experts based on Bayesian Network to reason under uncertain circumstance. Credal network method could analyze and get the joint probability interval of the formation nodes of risk factors to make use of the combination of quantitative and qualitative analysis methods. At the same time, this method could establish the Credal network direct acyclic graphs (DAG) of Operational Risk for commercial banks so as to propose the new reference model for Operational Risk measurement. The research purpose expects to provide the efficiency and validity methods to apply to the Operational Risk measurement for commercial banks.