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Cold spraying is being developed as effective and promising additive manufacturing process. However, how to create a deposit by cold spraying with comparable properties to bulk material is still challenge. It is well known that post-spray annealing is an effective process to enhance the deposit properties. In this paper, copper deposits are cold-sprayed at three different sets of spray conditions corresponding to three mean particle velocities of 578, 745, and 807 m/s. The tensile strength, thermal conductivity and electrical conductivity are measured at three different directions to clarify the anisotropy of deposit properties, which are parallel to gun moving direction and other two perpendicular directions. Furthermore, the influence of post-spray annealing on the anisotropy effect is also investigated by examining the effect of spray conditions and annealing conditions on the deposit properties at three different directions. The results clearly demonstrate the anisotropy of as-deposited Cu. Although it can be found that post-spray annealing significantly improves the properties of the as-sprayed deposits and reduces anisotropy of Cu deposit properties, the microstructure of the as-sprayed initial Cu deposit presents a significant effect on final annealed deposit. Therefore, an optimized cold-sprayed deposit will benefit manufacturing of a deposit with comparable properties with bulk by cold-spraying combined with post-spray annealing.

The aim of this study was to evaluate the usefulness of ultrasound in pregnancies with a positive non-invasive prenatal testing (NIPT) result for trisomy 18/13.

Photocatalytic degradation kinetics of methylene blue in aqueous solution was systematically investigated using Ti-based composite material as the photocatalyst. The single-variable-at-a-time ( SVAT) method was employed. It studied the individual and synergistic effects of several classical parameters on photocatalytic efficiencies. The kinetic mechanism was systematically explored. The kinetics effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The factors on the degradation of MB were in accordance with the pseudo first order kinetic model. This kinetic model followed the Langmuir–Hinshelwood model. The best preparation conditions were found in the experiments. It is proved that the Ti-based composite material is an effective adsorbent for the degradation of dye contaminated water.

In this work, the novel Ti-based composite material has been synthesized, characterized and studied for the photocatalytic degradation of methylene blue(MB). The effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The strong synergism of La, N and TiO2 was discussed during the photocatalytic process. The results suggested that the degradation efficiency was obviously improved by the Ti-based photocatalyst and the La element could enhance the photocatalytic degradation performance significantly, and the best molar ratio of N and TiO2 was 0.000014:1. The study found that the best preparation conditions can also improve the photocatalytic activity, the optimal material was made after calcining for 4h at 800°C. What is more, the higher illumination power was benifit for the degradation of the MB. It is indicated that the mixed crystal Ti-based composite material being an effective adsorbent for the elimination of the contaminated water by dyes. In addition, the work provide new direction for future research.

Previous studies show that several pathways are involved in sanguinarine-induced apoptotic cell death, including AKT downregulation, inhibition of NF-kB activation, mediation of ROS production, downregulation of anti-apoptosis proteins XIAP and cIAP-1, upregulation of BAX, and downregulation of BCL2. In this study, we found out that the quenching of ROS generation by N-acetyl-l-cysteine (NAC), a scavenger of ROS, reversed sanguinarine-induced apoptosis effects, also we found out that sanguinarine-induced rat hepatic stellate T6 cells (HSC-T6 cells) apoptosis was correlated with the generation of increased ROS, which was followed by the activation of caspase-8 (-3, -6, and -9), and the decreasing in the miltochondrial membrane potential (MMP) and the down-regulation of anti-apoptotic protein Bcl-2. It is not clear whether BCL2's downregulation relates to its promoter methylation and miR-15a/16-1 expression which can bind to BCL2 3′-UTR (un-translation reagon). We showed that sanguinarine-induced down regulation of BCL2 was associated with the increased methylation rate of BCL2 promotor district and the increased expression of miR-15a/16-1. HSC-T6 cells treatment with 5-Aza-2'-deoxycytidine (5′-Aza-CdR) impeded sanguinarine-induced BCL2 promotor district methylation and recovered BCL2's expression. Over expression of BCL2 using pEGFP-N1 vector decreased sanguinarine-induced HSC-T6 cells apoptotic death significantly but not completely. These observations clearly showed that BCL2 down regulation was associated with its promoter methylation and miR-15a/16-1 upregulation in sanguinarine-induced Rat HSC-T6 cells.

According to the current situation that most kind of automobile engine box were taken off-line random testing and the key technology of on-line detection, after the analysis of precision index and geometrical tolerances, the on-line testing model has been made by us. According to the model: ? double array CCD have been used to calibrate the positioning pin holes; ? image processing measurement method based on linear CCD has been determined; ? automatic control method in which grating control scanning step distance has been adopted to improve the accuracy of image collection; ? image edge extraction algorithm has been used to realize automatic fast testing. Experimental results show that: effective and rapid precise measurement can be achieved.

An experimental investigation was conducted on 4100 engine to study the influences of different percentages of methanol in DME/diesel blended fuel on combustion and emission performance. The result indicates that a certain amount of methanol in DME/diesel blended fuel can reduce production cost, improve the engine's power performance at the same time, but when the methanol percentage is increased (over 2%), the power performance will decrease. With the increase of methanol proportions, the maximum cylinder pressure is slightly increased, the peak of heat-release curves are declined and delayed, the cylinder temperature is decreased, the ignition timings are delayed and the combustion duration is shortened. In addition, NOx emissions were further reduced, but the HC emission, the CO emission and the soot emission has a little rise.

Methanol and diesel are almost not soluble, which greatly limits the further study and popularization of the methanol-diesel fuel. To study the emission and combustion characteristics, the 4100 turbocharged and intercooled diesel engine was fueled with 0# diesel and M10 with different additives in the experiment. The result shows that, the maximum cylinder pressure and the peak of the heat release rate in the initial stage of combustion for M10 with iso-octanol and isooctyl nitrate as additive are higher than that of diesel, while the soot emission is lower and NOx emission is slightly higher than diesel’. The maximum cylinder pressure and the heat-release peak in the initial stage of combustion for M10 with dimethyl ether as additive are both lower than diesel’, and the NOx and soot emissions are obviously decreased. The power of the two blend fuels is lower than that of diesel but the magnitude is small, meanwhile the HC emission is slightly increased, while the CO emission is little declined.

A variable-grain strategy is proposed to solve the complicated problem of optimization design on high-speed transmission helical gears with multiple objectives and restrictions. Based on the theory of gear meshing noise and the superiority criteria, a multi-objective evaluation index system is brought forward which gives consideration to the increase of the contact ratio and the decrease of the noise generated by the slide ratio of the tooth flank meshing and the mutation of friction torque, and then the variable-grain multi-objective optimization models of high-speed helical gears are established. The coarse-grained model is utilized in the early design to efficiently determine the direction to the optimal solution. Then the grain is refined and the fine-grained model can be utilized to acquire the optimal result.